path: root/mail/message-list.c

/*
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) version 3.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with the program; if not, see <http://www.gnu.org/licenses/>
 *
 *
 * Authors:
 *      Miguel de Icaza (miguel@ximian.com)
 *      Bertrand Guiheneuf (bg@aful.org)
 *      And just about everyone else in evolution ...
 *
 * Copyright (C) 1999-2008 Novell, Inc. (www.novell.com)
 *
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include "message-list.h"

#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>

#include <string.h>
#include <ctype.h>

#include <glib/gi18n.h>
#include <glib/gstdio.h>

#include "libemail-engine/e-mail-utils.h"
#include "libemail-engine/mail-config.h"
#include "libemail-engine/mail-mt.h"
#include "libemail-engine/mail-ops.h"
#include "libemail-engine/mail-tools.h"

#include "e-mail-label-list-store.h"
#include "e-mail-ui-session.h"
#include "em-utils.h"

/*#define TIMEIT */

#ifdef TIMEIT
#include <sys/time.h>
#include <unistd.h>
#endif

#ifdef G_OS_WIN32
#ifdef gmtime_r
#undef gmtime_r
#endif
#ifdef localtime_r
#undef localtime_r
#endif

/* The gmtime() and localtime() in Microsoft's C library are MT-safe */
#define gmtime_r(tp,tmp) (gmtime(tp)?(*(tmp)=*gmtime(tp),(tmp)):0)
#define localtime_r(tp,tmp) (localtime(tp)?(*(tmp)=*localtime(tp),(tmp)):0)
#endif

#define d(x)
#define t(x)

#define MESSAGE_LIST_GET_PRIVATE(obj) \
    (G_TYPE_INSTANCE_GET_PRIVATE \
    ((obj), MESSAGE_LIST_TYPE, MessageListPrivate))

/* Common search expression segments. */
#define EXCLUDE_DELETED_MESSAGES_EXPR   "(not (system-flag \"deleted\"))"
#define EXCLUDE_JUNK_MESSAGES_EXPR  "(not (system-flag \"junk\"))"

typedef struct _RegenData RegenData;

struct _MLSelection {
    GPtrArray *uids;
    CamelFolder *folder;
};

struct _MessageListPrivate {
    GtkWidget *invisible;   /* 4 selection */

    EMailSession *session;

    CamelFolder *folder;
    gulong folder_changed_handler_id;

    /* For message list regeneration. */
    GMutex regen_lock;
    RegenData *regen_data;
    guint regen_idle_id;

    struct _MLSelection clipboard;
    gboolean destroyed;

    gboolean expanded_default;
    gboolean group_by_threads;
    gboolean show_deleted;
    gboolean thread_latest;
    gboolean thread_subject;
    gboolean any_row_changed; /* save state before regen list when this is set to true */

    GtkTargetList *copy_target_list;
    GtkTargetList *paste_target_list;

    /* XXX Not sure if we really need a separate frozen counter
     *     for the tree model but the old ETreeMemory class had
     *     its own frozen counter so we preserve it here. */
    GNode *tree_model_root;
    gint tree_model_frozen;

    /* This aids in automatic message selection. */
    time_t newest_read_date;
    const gchar *newest_read_uid;
    time_t oldest_unread_date;
    const gchar *oldest_unread_uid;
};

struct _RegenData {
    volatile gint ref_count;

    EActivity *activity;
    MessageList *message_list;

    gchar *search;

    gboolean group_by_threads;
    gboolean thread_subject;
    CamelFolderThread *tree;

    /* This indicates we're regenerating the message list because
     * we received a "folder-changed" signal from our CamelFolder. */
    gboolean folder_changed;

    CamelFolder *folder;
    GPtrArray *summary;

    gint last_row; /* last selected (cursor) row */

    xmlDoc *expand_state; /* expanded state to be restored */

    /* These may be set during a regen operation.  Use the
     * select_lock to ensure consistency and thread-safety.
     * These are applied after the operation is finished. */
    GMutex select_lock;
    gchar *select_uid;
    gboolean select_all;
    gboolean select_use_fallback;
};

enum {
    PROP_0,
    PROP_COPY_TARGET_LIST,
    PROP_FOLDER,
    PROP_GROUP_BY_THREADS,
    PROP_PASTE_TARGET_LIST,
    PROP_SESSION,
    PROP_SHOW_DELETED,
    PROP_THREAD_LATEST,
    PROP_THREAD_SUBJECT
};

/* Forward Declarations */
static void message_list_selectable_init
                    (ESelectableInterface *interface);
static void message_list_tree_model_init
                    (ETreeModelInterface *interface);
static gboolean message_list_get_hide_deleted
                    (MessageList *message_list,
                     CamelFolder *folder);

G_DEFINE_TYPE_WITH_CODE (
    MessageList,
    message_list,
    E_TYPE_TREE,
    G_IMPLEMENT_INTERFACE (
        E_TYPE_EXTENSIBLE, NULL)
    G_IMPLEMENT_INTERFACE (
        E_TYPE_SELECTABLE,
        message_list_selectable_init)
    G_IMPLEMENT_INTERFACE (
        E_TYPE_TREE_MODEL,
        message_list_tree_model_init))

static struct {
    const gchar *target;
    GdkAtom atom;
    guint32 actions;
} ml_drag_info[] = {
    { "x-uid-list", NULL, GDK_ACTION_MOVE | GDK_ACTION_COPY },
    { "message/rfc822", NULL, GDK_ACTION_COPY },
    { "text/uri-list", NULL, GDK_ACTION_COPY },
};

enum {
    DND_X_UID_LIST,     /* x-uid-list */
    DND_MESSAGE_RFC822, /* message/rfc822 */
    DND_TEXT_URI_LIST   /* text/uri-list */
};

/* What we send */
static GtkTargetEntry ml_drag_types[] = {
    { (gchar *) "x-uid-list", 0, DND_X_UID_LIST },
    { (gchar *) "text/uri-list", 0, DND_TEXT_URI_LIST },
};

/* What we accept */
static GtkTargetEntry ml_drop_types[] = {
    { (gchar *) "x-uid-list", 0, DND_X_UID_LIST },
    { (gchar *) "message/rfc822", 0, DND_MESSAGE_RFC822 },
    { (gchar *) "text/uri-list", 0, DND_TEXT_URI_LIST },
};

/*
 * Default sizes for the ETable display
 *
 */
#define N_CHARS(x) (CHAR_WIDTH * (x))

#define COL_ICON_WIDTH         (16)
#define COL_ATTACH_WIDTH       (16)
#define COL_CHECK_BOX_WIDTH    (16)
#define COL_FROM_EXPANSION     (24.0)
#define COL_FROM_WIDTH_MIN     (32)
#define COL_SUBJECT_EXPANSION  (30.0)
#define COL_SUBJECT_WIDTH_MIN  (32)
#define COL_SENT_EXPANSION     (24.0)
#define COL_SENT_WIDTH_MIN     (32)
#define COL_RECEIVED_EXPANSION (20.0)
#define COL_RECEIVED_WIDTH_MIN (32)
#define COL_TO_EXPANSION       (24.0)
#define COL_TO_WIDTH_MIN       (32)
#define COL_SIZE_EXPANSION     (6.0)
#define COL_SIZE_WIDTH_MIN     (32)
#define COL_SENDER_EXPANSION     (24.0)
#define COL_SENDER_WIDTH_MIN     (32)

enum {
    NORMALISED_SUBJECT,
    NORMALISED_FROM,
    NORMALISED_TO,
    NORMALISED_LAST
};

static void on_cursor_activated_cmd     (ETree *tree,
                         gint row,
                         GNode *node,
                         gpointer user_data);
static void on_selection_changed_cmd    (ETree *tree,
                         MessageList *message_list);
static gint on_click            (ETree *tree,
                         gint row,
                         GNode *node,
                         gint col,
                         GdkEvent *event,
                         MessageList *message_list);

static void mail_regen_list         (MessageList *message_list,
                         const gchar *search,
                         gboolean folder_changed);
static void mail_regen_cancel       (MessageList *message_list);

static void clear_info          (gchar *key,
                         GNode *node,
                         MessageList *message_list);

enum {
    MESSAGE_SELECTED,
    MESSAGE_LIST_BUILT,
    LAST_SIGNAL
};

static guint signals[LAST_SIGNAL] = {0, };

static const gchar *status_map[] = {
    N_("Unseen"),
    N_("Seen"),
    N_("Answered"),
    N_("Forwarded"),
    N_("Multiple Unseen Messages"),
    N_("Multiple Messages"),
};

static const gchar *status_icons[] = {
    "mail-unread",
    "mail-read",
    "mail-replied",
    "mail-forward",
    "stock_mail-unread-multiple",
    "stock_mail-open-multiple"
};

static const gchar *score_map[] = {
    N_("Lowest"),
    N_("Lower"),
    N_("Low"),
    N_("Normal"),
    N_("High"),
    N_("Higher"),
    N_("Highest"),
};

static const gchar *score_icons[] = {
    "stock_score-lowest",
    "stock_score-lower",
    "stock_score-low",
    "stock_score-normal",
    "stock_score-high",
    "stock_score-higher",
    "stock_score-highest"
};

static const gchar *attachment_icons[] = {
    NULL,  /* empty icon */
    "mail-attachment",
    "stock_new-meeting"
};

static const gchar *flagged_icons[] = {
    NULL,  /* empty icon */
    "emblem-important"
};

static const gchar *followup_icons[] = {
    NULL,  /* empty icon */
    "stock_mail-flag-for-followup",
    "stock_mail-flag-for-followup-done"
};

static RegenData *
regen_data_new (MessageList *message_list,
                GCancellable *cancellable)
{
    RegenData *regen_data;
    EActivity *activity;
    EMailSession *session;
    gboolean searching;

    activity = e_activity_new ();
    e_activity_set_cancellable (activity, cancellable);
    e_activity_set_text (activity, _("Generating message list"));

    regen_data = g_slice_new0 (RegenData);
    regen_data->ref_count = 1;
    regen_data->activity = g_object_ref (activity);
    regen_data->message_list = g_object_ref (message_list);
    regen_data->last_row = -1;

    /* Capture MessageList state to use for this regen. */

    regen_data->folder =
        message_list_ref_folder (message_list);
    regen_data->group_by_threads =
        message_list_get_group_by_threads (message_list);
    regen_data->thread_subject =
        message_list_get_thread_subject (message_list);

    if (message_list->thread_tree != NULL) {
        CamelFolderThread *thread_tree;
        gboolean hide_deleted;

        thread_tree = message_list->thread_tree;
        hide_deleted = message_list_get_hide_deleted (
            message_list, regen_data->folder);

        if (regen_data->group_by_threads && hide_deleted) {
            regen_data->tree = thread_tree;
            camel_folder_thread_messages_ref (thread_tree);
        } else {
            camel_folder_thread_messages_unref (thread_tree);
            message_list->thread_tree = NULL;
        }
    }

    searching = (g_strcmp0 (message_list->search, " ") != 0);

    if (e_tree_row_count (E_TREE (message_list)) <= 0) {
        if (gtk_widget_get_visible (GTK_WIDGET (message_list))) {
            gchar *txt;

            txt = g_strdup_printf (
                "%s...", _("Generating message list"));
            e_tree_set_info_message (E_TREE (message_list), txt);
            g_free (txt);
        }

    } else if (regen_data->group_by_threads &&
           !message_list->just_set_folder &&
           !searching) {

        ETreeTableAdapter *adapter;

        adapter = e_tree_get_table_adapter (E_TREE (message_list));

        if (message_list->priv->any_row_changed) {
            /* Something changed.  If it was an expand
             * state change, then save the expand state. */
            message_list_save_state (message_list);
        } else {
            /* Remember the expand state and restore it
             * after regen. */
            regen_data->expand_state =
                e_tree_table_adapter_save_expanded_state_xml (
                adapter);
        }
    }

    g_mutex_init (&regen_data->select_lock);

    session = message_list_get_session (message_list);
    e_mail_ui_session_add_activity (E_MAIL_UI_SESSION (session), activity);

    g_object_unref (activity);

    return regen_data;
}

static RegenData *
regen_data_ref (RegenData *regen_data)
{
    g_return_val_if_fail (regen_data != NULL, NULL);
    g_return_val_if_fail (regen_data->ref_count > 0, NULL);

    g_atomic_int_inc (&regen_data->ref_count);

    return regen_data;
}

static void
regen_data_unref (RegenData *regen_data)
{
    g_return_if_fail (regen_data != NULL);
    g_return_if_fail (regen_data->ref_count > 0);

    if (g_atomic_int_dec_and_test (&regen_data->ref_count)) {

        g_clear_object (&regen_data->activity);
        g_clear_object (&regen_data->message_list);

        g_free (regen_data->search);

        if (regen_data->tree != NULL)
            camel_folder_thread_messages_unref (regen_data->tree);

        if (regen_data->summary != NULL) {
            guint ii, length;

            length = regen_data->summary->len;

            for (ii = 0; ii < length; ii++)
                camel_folder_free_message_info (
                    regen_data->folder,
                    regen_data->summary->pdata[ii]);

            g_ptr_array_free (regen_data->summary, TRUE);
        }

        g_clear_object (&regen_data->folder);

        if (regen_data->expand_state != NULL)
            xmlFreeDoc (regen_data->expand_state);

        g_mutex_clear (&regen_data->select_lock);
        g_free (regen_data->select_uid);

        g_slice_free (RegenData, regen_data);
    }
}

static RegenData *
message_list_ref_regen_data (MessageList *message_list)
{
    RegenData *regen_data = NULL;

    g_mutex_lock (&message_list->priv->regen_lock);

    if (message_list->priv->regen_data != NULL)
        regen_data = regen_data_ref (message_list->priv->regen_data);

    g_mutex_unlock (&message_list->priv->regen_lock);

    return regen_data;
}

static void
message_list_tree_model_freeze (MessageList *message_list)
{
    if (message_list->priv->tree_model_frozen == 0)
        e_tree_model_pre_change (E_TREE_MODEL (message_list));

    message_list->priv->tree_model_frozen++;
}

static void
message_list_tree_model_thaw (MessageList *message_list)
{
    if (message_list->priv->tree_model_frozen > 0)
        message_list->priv->tree_model_frozen--;

    if (message_list->priv->tree_model_frozen == 0)
        e_tree_model_node_changed (
            E_TREE_MODEL (message_list),
            message_list->priv->tree_model_root);
}

static GNode *
message_list_tree_model_insert (MessageList *message_list,
                                GNode *parent,
                                gint position,
                                gpointer data)
{
    ETreeModel *tree_model;
    GNode *node;
    gboolean tree_model_frozen;

    if (parent == NULL)
        g_return_val_if_fail (
            message_list->priv->tree_model_root == NULL, NULL);

    tree_model = E_TREE_MODEL (message_list);
    tree_model_frozen = (message_list->priv->tree_model_frozen > 0);

    if (!tree_model_frozen)
        e_tree_model_pre_change (tree_model);

    node = g_node_new (data);

    if (parent != NULL) {
        g_node_insert (parent, position, node);
        if (!tree_model_frozen)
            e_tree_model_node_inserted (tree_model, parent, node);
    } else {
        message_list->priv->tree_model_root = node;
        if (!tree_model_frozen)
            e_tree_model_node_changed (tree_model, node);
    }

    return node;
}

static void
message_list_tree_model_remove (MessageList *message_list,
                                GNode *node)
{
    ETreeModel *tree_model;
    GNode *parent = node->parent;
    gboolean tree_model_frozen;
    gint old_position = 0;

    g_return_if_fail (node != NULL);

    tree_model = E_TREE_MODEL (message_list);
    tree_model_frozen = (message_list->priv->tree_model_frozen > 0);

    if (!tree_model_frozen) {
        e_tree_model_pre_change (tree_model);
        old_position = g_node_child_position (parent, node);
    }

    g_node_unlink (node);

    if (!tree_model_frozen)
        e_tree_model_node_removed (
            tree_model, parent, node, old_position);

    g_node_destroy (node);

    if (node == message_list->priv->tree_model_root)
        message_list->priv->tree_model_root = NULL;

    if (!tree_model_frozen)
        e_tree_model_node_deleted (tree_model, node);
}

static gint
address_compare (gconstpointer address1,
                 gconstpointer address2,
                 gpointer cmp_cache)
{
    gint retval;

    g_return_val_if_fail (address1 != NULL, 1);
    g_return_val_if_fail (address2 != NULL, -1);

    retval = g_ascii_strcasecmp ((gchar *) address1, (gchar *) address2);

    return retval;
}

static gchar *
filter_size (gint size)
{
    gfloat fsize;

    if (size < 1024) {
        return g_strdup_printf ("%d", size);
    } else {
        fsize = ((gfloat) size) / 1024.0;
        if (fsize < 1024.0) {
            return g_strdup_printf ("%.2f K", fsize);
        } else {
            fsize /= 1024.0;
            return g_strdup_printf ("%.2f M", fsize);
        }
    }
}

/* Gets the uid of the message displayed at a given view row */
static const gchar *
get_message_uid (MessageList *message_list,
                 GNode *node)
{
    g_return_val_if_fail (node != NULL, NULL);
    g_return_val_if_fail (node->data != NULL, NULL);

    return camel_message_info_uid (node->data);
}

/* Gets the CamelMessageInfo for the message displayed at the given
 * view row.
 */
static CamelMessageInfo *
get_message_info (MessageList *message_list,
                  GNode *node)
{
    g_return_val_if_fail (node != NULL, NULL);
    g_return_val_if_fail (node->data != NULL, NULL);

    return node->data;
}

static const gchar *
get_normalised_string (MessageList *message_list,
                       CamelMessageInfo *info,
                       gint col)
{
    const gchar *string, *str;
    gchar *normalised;
    EPoolv *poolv;
    gint index;

    switch (col) {
    case COL_SUBJECT_NORM:
        string = camel_message_info_subject (info);
        index = NORMALISED_SUBJECT;
        break;
    case COL_FROM_NORM:
        string = camel_message_info_from (info);
        index = NORMALISED_FROM;
        break;
    case COL_TO_NORM:
        string = camel_message_info_to (info);
        index = NORMALISED_TO;
        break;
    default:
        string = NULL;
        index = NORMALISED_LAST;
        g_warning ("Should not be reached\n");
    }

    /* slight optimisation */
    if (string == NULL || string[0] == '\0')
        return "";

    poolv = g_hash_table_lookup (message_list->normalised_hash, camel_message_info_uid (info));
    if (poolv == NULL) {
        poolv = e_poolv_new (NORMALISED_LAST);
        g_hash_table_insert (message_list->normalised_hash, (gchar *) camel_message_info_uid (info), poolv);
    } else {
        str = e_poolv_get (poolv, index);
        if (*str)
            return str;
    }

    if (col == COL_SUBJECT_NORM) {
        gint skip_len;
        const gchar *subject;
        gboolean found_re = TRUE;

        subject = string;
        while (found_re) {
            found_re = em_utils_is_re_in_subject (
                subject, &skip_len) && skip_len > 0;
            if (found_re)
                subject += skip_len;

            /* jump over any spaces */
            while (*subject && isspace ((gint) *subject))
                subject++;
        }

        /* jump over any spaces */
        while (*subject && isspace ((gint) *subject))
            subject++;

        string = subject;
        normalised = g_utf8_collate_key (string, -1);
    } else {
        /* because addresses require strings, not collate keys */
        normalised = g_strdup (string);
    }

    e_poolv_set (poolv, index, normalised, TRUE);

    return e_poolv_get (poolv, index);
}

static void
clear_selection (MessageList *message_list,
                 struct _MLSelection *selection)
{
    if (selection->uids != NULL) {
        g_ptr_array_unref (selection->uids);
        selection->uids = NULL;
    }

    g_clear_object (&selection->folder);
}

static GNode *
ml_search_forward (MessageList *message_list,
                   gint start,
                   gint end,
                   guint32 flags,
                   guint32 mask)
{
    GNode *node;
    gint row;
    CamelMessageInfo *info;
    ETreeTableAdapter *etta;

    etta = e_tree_get_table_adapter (E_TREE (message_list));

    for (row = start; row <= end; row++) {
        node = e_tree_table_adapter_node_at_row (etta, row);
        if (node != NULL
            && (info = get_message_info (message_list, node))
            && (camel_message_info_flags (info) & mask) == flags)
            return node;
    }

    return NULL;
}

static GNode *
ml_search_backward (MessageList *message_list,
                    gint start,
                    gint end,
                    guint32 flags,
                    guint32 mask)
{
    GNode *node;
    gint row;
    CamelMessageInfo *info;
    ETreeTableAdapter *etta;

    etta = e_tree_get_table_adapter (E_TREE (message_list));

    for (row = start; row >= end; row--) {
        node = e_tree_table_adapter_node_at_row (etta, row);
        if (node != NULL
            && (info = get_message_info (message_list, node))
            && (camel_message_info_flags (info) & mask) == flags)
            return node;
    }

    return NULL;
}

static GNode *
ml_search_path (MessageList *message_list,
                MessageListSelectDirection direction,
                guint32 flags,
                guint32 mask)
{
    GNode *node;
    gint row, count;
    ETreeTableAdapter *etta;

    etta = e_tree_get_table_adapter (E_TREE (message_list));

    if (message_list->cursor_uid == NULL
        || (node = g_hash_table_lookup (message_list->uid_nodemap, message_list->cursor_uid)) == NULL)
        return NULL;

    row = e_tree_table_adapter_row_of_node (etta, node);
    if (row == -1)
        return NULL;
    count = e_table_model_row_count ((ETableModel *) etta);

    if ((direction & MESSAGE_LIST_SELECT_DIRECTION) == MESSAGE_LIST_SELECT_NEXT)
        node = ml_search_forward (
            message_list, row + 1, count - 1, flags, mask);
    else
        node = ml_search_backward (
            message_list, row - 1, 0, flags, mask);

    if (node == NULL && (direction & MESSAGE_LIST_SELECT_WRAP)) {
        if ((direction & MESSAGE_LIST_SELECT_DIRECTION) == MESSAGE_LIST_SELECT_NEXT)
            node = ml_search_forward (
                message_list, 0, row, flags, mask);
        else
            node = ml_search_backward (
                message_list, count - 1, row, flags, mask);
    }

    return node;
}

static void
select_node (MessageList *message_list,
             GNode *node)
{
    ETree *tree;
    ETreeTableAdapter *etta;
    ETreeSelectionModel *etsm;

    tree = E_TREE (message_list);
    etta = e_tree_get_table_adapter (tree);
    etsm = (ETreeSelectionModel *) e_tree_get_selection_model (tree);

    g_free (message_list->cursor_uid);
    message_list->cursor_uid = NULL;

    e_tree_table_adapter_show_node (etta, node);
    e_tree_set_cursor (tree, node);
    e_tree_selection_model_select_single_path (etsm, node);
}

/**
 * message_list_select:
 * @message_list: a MessageList
 * @direction: the direction to search in
 * @flags: a set of flag values
 * @mask: a mask for comparing against @flags
 *
 * This moves the message list selection to a suitable row. @flags and
 * @mask combine to specify what constitutes a suitable row. @direction is
 * %MESSAGE_LIST_SELECT_NEXT if it should find the next matching
 * message, or %MESSAGE_LIST_SELECT_PREVIOUS if it should find the
 * previous. %MESSAGE_LIST_SELECT_WRAP is an option bit which specifies the
 * search should wrap.
 *
 * If no suitable row is found, the selection will be
 * unchanged.
 *
 * Returns %TRUE if a new message has been selected or %FALSE otherwise.
 **/
gboolean
message_list_select (MessageList *message_list,
                     MessageListSelectDirection direction,
                     guint32 flags,
                     guint32 mask)
{
    GNode *node;

    node = ml_search_path (message_list, direction, flags, mask);
    if (node != NULL) {
        select_node (message_list, node);

        /* This function is usually called in response to a key
         * press, so grab focus if the message list is visible. */
        if (gtk_widget_get_visible (GTK_WIDGET (message_list)))
            gtk_widget_grab_focus (GTK_WIDGET (message_list));

        return TRUE;
    } else
        return FALSE;
}

/**
 * message_list_can_select:
 * @message_list:
 * @direction:
 * @flags:
 * @mask:
 *
 * Returns true if the selection specified is possible with the current view.
 *
 * Return value:
 **/
gboolean
message_list_can_select (MessageList *message_list,
                         MessageListSelectDirection direction,
                         guint32 flags,
                         guint32 mask)
{
    return ml_search_path (message_list, direction, flags, mask) != NULL;
}

/**
 * message_list_select_uid:
 * @message_list:
 * @uid:
 *
 * Selects the message with the given UID.
 **/
void
message_list_select_uid (MessageList *message_list,
                         const gchar *uid,
                         gboolean with_fallback)
{
    MessageListPrivate *priv;
    GHashTable *uid_nodemap;
    GNode *node = NULL;
    RegenData *regen_data = NULL;

    g_return_if_fail (IS_MESSAGE_LIST (message_list));

    priv = message_list->priv;
    uid_nodemap = message_list->uid_nodemap;

    if (message_list->priv->folder == NULL)
        return;

    /* Try to find the requested message UID. */
    if (uid != NULL)
        node = g_hash_table_lookup (uid_nodemap, uid);

    regen_data = message_list_ref_regen_data (message_list);

    /* If we're busy or waiting to regenerate the message list, cache
     * the UID so we can try again when we're done.  Otherwise if the
     * requested message UID was not found and 'with_fallback' is set,
     * try a couple fallbacks:
     *
     * 1) Oldest unread message in the list, by date received.
     * 2) Newest read message in the list, by date received.
     */
    if (regen_data != NULL) {
        g_mutex_lock (&regen_data->select_lock);
        g_free (regen_data->select_uid);
        regen_data->select_uid = g_strdup (uid);
        regen_data->select_use_fallback = with_fallback;
        g_mutex_unlock (&regen_data->select_lock);

        regen_data_unref (regen_data);

    } else if (with_fallback) {
        if (node == NULL && priv->oldest_unread_uid != NULL)
            node = g_hash_table_lookup (
                uid_nodemap, priv->oldest_unread_uid);
        if (node == NULL && priv->newest_read_uid != NULL)
            node = g_hash_table_lookup (
                uid_nodemap, priv->newest_read_uid);
    }

    if (node) {
        ETree *tree;
        GNode *old_cur;

        tree = E_TREE (message_list);
        old_cur = e_tree_get_cursor (tree);

        /* This will emit a changed signal that we'll pick up */
        e_tree_set_cursor (tree, node);

        if (old_cur == node)
            g_signal_emit (
                message_list,
                signals[MESSAGE_SELECTED],
                0, message_list->cursor_uid);
    } else {
        g_free (message_list->cursor_uid);
        message_list->cursor_uid = NULL;
        g_signal_emit (
            message_list,
            signals[MESSAGE_SELECTED],
            0, NULL);
    }
}

void
message_list_select_next_thread (MessageList *message_list)
{
    GNode *node;
    ETreeTableAdapter *etta;
    gint i, count, row;

    g_return_if_fail (IS_MESSAGE_LIST (message_list));

    etta = e_tree_get_table_adapter (E_TREE (message_list));

    if (!message_list->cursor_uid
        || (node = g_hash_table_lookup (message_list->uid_nodemap, message_list->cursor_uid)) == NULL)
        return;

    row = e_tree_table_adapter_row_of_node (etta, node);
    if (row == -1)
        return;
    count = e_table_model_row_count ((ETableModel *) etta);

    /* find the next node which has a root parent (i.e. toplevel node) */
    for (i = row + 1; i < count - 1; i++) {
        node = e_tree_table_adapter_node_at_row (etta, i);
        if (node != NULL && G_NODE_IS_ROOT (node->parent)) {
            select_node (message_list, node);
            return;
        }
    }
}

void
message_list_select_prev_thread (MessageList *message_list)
{
    GNode *node;
    ETreeTableAdapter *etta;
    gint i, row;
    gboolean skip_first;

    g_return_if_fail (IS_MESSAGE_LIST (message_list));

    etta = e_tree_get_table_adapter (E_TREE (message_list));

    if (!message_list->cursor_uid
        || (node = g_hash_table_lookup (message_list->uid_nodemap, message_list->cursor_uid)) == NULL)
        return;

    row = e_tree_table_adapter_row_of_node (etta, node);
    if (row == -1)
        return;

    /* skip first found if in the middle of the thread */
    skip_first = !G_NODE_IS_ROOT (node->parent);

    /* find the previous node which has a root parent (i.e. toplevel node) */
    for (i = row - 1; i >= 0; i--) {
        node = e_tree_table_adapter_node_at_row (etta, i);
        if (node != NULL && G_NODE_IS_ROOT (node->parent)) {
            if (skip_first) {
                skip_first = FALSE;
                continue;
            }

            select_node (message_list, node);
            return;
        }
    }
}

/**
 * message_list_select_all:
 * @message_list: Message List widget
 *
 * Selects all messages in the message list.
 **/
void
message_list_select_all (MessageList *message_list)
{
    RegenData *regen_data = NULL;

    g_return_if_fail (IS_MESSAGE_LIST (message_list));

    regen_data = message_list_ref_regen_data (message_list);

    if (regen_data != NULL && regen_data->group_by_threads) {
        regen_data->select_all = TRUE;
    } else {
        ETree *tree;
        ESelectionModel *selection_model;

        tree = E_TREE (message_list);
        selection_model = e_tree_get_selection_model (tree);
        e_selection_model_select_all (selection_model);
    }

    if (regen_data != NULL)
        regen_data_unref (regen_data);
}

typedef struct thread_select_info {
    MessageList *message_list;
    GPtrArray *paths;
} thread_select_info_t;

static gboolean
select_thread_node (ETreeModel *model,
                    GNode *node,
                    gpointer user_data)
{
    thread_select_info_t *tsi = (thread_select_info_t *) user_data;

    g_ptr_array_add (tsi->paths, node);

    return FALSE; /*not done yet */
}

static void
select_thread (MessageList *message_list,
               ETreeForeachFunc selector)
{
    ETree *tree;
    ETreeSelectionModel *etsm;
    thread_select_info_t tsi;

    tsi.message_list = message_list;
    tsi.paths = g_ptr_array_new ();

    tree = E_TREE (message_list);
    etsm = (ETreeSelectionModel *) e_tree_get_selection_model (tree);

    e_tree_selection_model_foreach (etsm, selector, &tsi);

    e_tree_selection_model_select_paths (etsm, tsi.paths);

    g_ptr_array_free (tsi.paths, TRUE);
}

static void
thread_select_foreach (ETreePath path,
                       gpointer user_data)
{
    thread_select_info_t *tsi = (thread_select_info_t *) user_data;
    ETreeModel *tree_model;
    GNode *last, *node = path;

    tree_model = E_TREE_MODEL (tsi->message_list);

    do {
        last = node;
        node = node->parent;
    } while (!G_NODE_IS_ROOT (node));

    g_ptr_array_add (tsi->paths, last);

    e_tree_model_node_traverse (
        tree_model, last,
        (ETreePathFunc) select_thread_node, tsi);
}

/**
 * message_list_select_thread:
 * @message_list: Message List widget
 *
 * Selects all messages in the current thread (based on cursor).
 **/
void
message_list_select_thread (MessageList *message_list)
{
    select_thread (message_list, thread_select_foreach);
}

static void
subthread_select_foreach (ETreePath path,
                          gpointer user_data)
{
    thread_select_info_t *tsi = (thread_select_info_t *) user_data;
    ETreeModel *tree_model;

    tree_model = E_TREE_MODEL (tsi->message_list);

    e_tree_model_node_traverse (
        tree_model, path,
        (ETreePathFunc) select_thread_node, tsi);
}

/**
 * message_list_select_subthread:
 * @message_list: Message List widget
 *
 * Selects all messages in the current subthread (based on cursor).
 **/
void
message_list_select_subthread (MessageList *message_list)
{
    select_thread (message_list, subthread_select_foreach);
}

void
message_list_copy (MessageList *message_list,
                   gboolean cut)
{
    MessageListPrivate *p = message_list->priv;
    GPtrArray *uids;

    clear_selection (message_list, &p->clipboard);

    uids = message_list_get_selected (message_list);

    if (uids->len > 0) {
        if (cut) {
            CamelFolder *folder;
            gint i;

            folder = message_list_ref_folder (message_list);

            camel_folder_freeze (folder);

            for (i = 0; i < uids->len; i++)
                camel_folder_set_message_flags (
                    folder, uids->pdata[i],
                    CAMEL_MESSAGE_SEEN |
                    CAMEL_MESSAGE_DELETED,
                    CAMEL_MESSAGE_SEEN |
                    CAMEL_MESSAGE_DELETED);

            camel_folder_thaw (folder);

            g_object_unref (folder);
        }

        p->clipboard.uids = g_ptr_array_ref (uids);
        p->clipboard.folder = message_list_ref_folder (message_list);

        gtk_selection_owner_set (
            p->invisible,
            GDK_SELECTION_CLIPBOARD,
            gtk_get_current_event_time ());
    } else {
        gtk_selection_owner_set (
            NULL, GDK_SELECTION_CLIPBOARD,
            gtk_get_current_event_time ());
    }

    g_ptr_array_unref (uids);
}

void
message_list_paste (MessageList *message_list)
{
    gtk_selection_convert (
        message_list->priv->invisible,
        GDK_SELECTION_CLIPBOARD,
        gdk_atom_intern ("x-uid-list", FALSE),
        GDK_CURRENT_TIME);
}

static void
for_node_and_subtree_if_collapsed (MessageList *message_list,
                                   GNode *node,
                                   CamelMessageInfo *mi,
                                   ETreePathFunc func,
                                   gpointer data)
{
    ETreeModel *tree_model;
    ETreeTableAdapter *adapter;
    GNode *child = NULL;

    tree_model = E_TREE_MODEL (message_list);
    adapter = e_tree_get_table_adapter (E_TREE (message_list));

    func (NULL, (ETreePath) mi, data);

    if (node != NULL)
        child = g_node_first_child (node);

    if (child && !e_tree_table_adapter_node_is_expanded (adapter, node))
        e_tree_model_node_traverse (tree_model, node, func, data);
}

static gboolean
unread_foreach (ETreeModel *etm,
                ETreePath path,
                gpointer data)
{
    gboolean *saw_unread = data;
    CamelMessageInfo *info;

    if (!etm)
        info = (CamelMessageInfo *) path;
    else
        info = ((GNode *) path)->data;
    g_return_val_if_fail (info != NULL, FALSE);

    if (!(camel_message_info_flags (info) & CAMEL_MESSAGE_SEEN))
        *saw_unread = TRUE;

    return FALSE;
}

struct LatestData {
    gboolean sent;
    time_t latest;
};

static gboolean
latest_foreach (ETreeModel *etm,
                ETreePath path,
                gpointer data)
{
    struct LatestData *ld = data;
    CamelMessageInfo *info;
    time_t date;

    if (!etm)
        info = (CamelMessageInfo *) path;
    else
        info = ((GNode *) path)->data;
    g_return_val_if_fail (info != NULL, FALSE);

    date = ld->sent ? camel_message_info_date_sent (info)
            : camel_message_info_date_received (info);

    if (ld->latest == 0 || date > ld->latest)
        ld->latest = date;

    return FALSE;
}

static gchar *
sanitize_recipients (const gchar *string)
{
    GString     *gstring;
    gboolean     quoted = FALSE;
    const gchar *p;
    GString *recipients = g_string_new ("");
    gchar *single_add;
    gchar **name;

    if (!string || !*string)
        return (gchar *) "";

    gstring = g_string_new ("");

    for (p = string; *p; p = g_utf8_next_char (p)) {
        gunichar c = g_utf8_get_char (p);

        if (c == '"')
            quoted = ~quoted;
        else if (c == ',' && !quoted) {
            single_add = g_string_free (gstring, FALSE);
            name = g_strsplit (single_add,"<",2);
            g_string_append (recipients, *name);
            g_string_append (recipients, ",");
            g_free (single_add);
            g_strfreev (name);
            gstring = g_string_new ("");
            continue;
        }

        g_string_append_unichar (gstring, c);
    }

    single_add = g_string_free (gstring, FALSE);
    name = g_strsplit (single_add,"<",2);
    g_string_append (recipients, *name);
    g_free (single_add);
    g_strfreev (name);

    return g_string_free (recipients, FALSE);
}

struct LabelsData {
    EMailLabelListStore *store;
    GHashTable *labels_tag2iter;
};

static void
add_label_if_known (struct LabelsData *ld,
                    const gchar *tag)
{
    GtkTreeIter label_defn;

    if (e_mail_label_list_store_lookup (ld->store, tag, &label_defn)) {
        g_hash_table_insert (
            ld->labels_tag2iter,
            /* Should be the same as the "tag" arg */
            e_mail_label_list_store_get_tag (ld->store, &label_defn),
            gtk_tree_iter_copy (&label_defn));
    }
}

static gboolean
add_all_labels_foreach (ETreeModel *etm,
                        ETreePath path,
                        gpointer data)
{
    struct LabelsData *ld = data;
    CamelMessageInfo *msg_info;
    const gchar *old_label;
    gchar *new_label;
    const CamelFlag *flag;

    if (!etm)
        msg_info = (CamelMessageInfo *) path;
    else
        msg_info = ((GNode *) path)->data;
    g_return_val_if_fail (msg_info != NULL, FALSE);

    for (flag = camel_message_info_user_flags (msg_info); flag; flag = flag->next)
        add_label_if_known (ld, flag->name);

    old_label = camel_message_info_user_tag (msg_info, "label");
    if (old_label != NULL) {
        /* Convert old-style labels ("<name>") to "$Label<name>". */
        new_label = g_alloca (strlen (old_label) + 10);
        g_stpcpy (g_stpcpy (new_label, "$Label"), old_label);

        add_label_if_known (ld, new_label);
    }

    return FALSE;
}

static const gchar *
get_trimmed_subject (CamelMessageInfo *info)
{
    const gchar *subject;
    const gchar *mlist;
    gint mlist_len = 0;
    gboolean found_mlist;

    subject = camel_message_info_subject (info);
    if (!subject || !*subject)
        return subject;

    mlist = camel_message_info_mlist (info);

    if (mlist && *mlist) {
        const gchar *mlist_end;

        mlist_end = strchr (mlist, '@');
        if (mlist_end)
            mlist_len = mlist_end - mlist;
        else
            mlist_len = strlen (mlist);
    }

    do {
        gint skip_len;
        gboolean found_re = TRUE;

        found_mlist = FALSE;

        while (found_re) {
            found_re = FALSE;

            found_re = em_utils_is_re_in_subject (
                subject, &skip_len) && skip_len > 0;
            if (found_re)
                subject += skip_len;

            /* jump over any spaces */
            while (*subject && isspace ((gint) *subject))
                subject++;
        }

        if (mlist_len &&
            *subject == '[' &&
            !g_ascii_strncasecmp ((gchar *) subject + 1, mlist, mlist_len) &&
            subject[1 + mlist_len] == ']') {
            subject += 1 + mlist_len + 1;  /* jump over "[mailing-list]" */
            found_mlist = TRUE;

            /* jump over any spaces */
            while (*subject && isspace ((gint) *subject))
                subject++;
        }
    } while (found_mlist);

    /* jump over any spaces */
    while (*subject && isspace ((gint) *subject))
        subject++;

    return subject;
}

static gpointer
ml_tree_value_at_ex (ETreeModel *etm,
                     GNode *node,
                     gint col,
                     CamelMessageInfo *msg_info,
                     MessageList *message_list)
{
    EMailSession *session;
    const gchar *str;
    guint32 flags;

    session = message_list_get_session (message_list);

    g_return_val_if_fail (msg_info != NULL, NULL);

    switch (col) {
    case COL_MESSAGE_STATUS:
        flags = camel_message_info_flags (msg_info);
        if (flags & CAMEL_MESSAGE_ANSWERED)
            return GINT_TO_POINTER (2);
        else if (flags & CAMEL_MESSAGE_FORWARDED)
            return GINT_TO_POINTER (3);
        else if (flags & CAMEL_MESSAGE_SEEN)
            return GINT_TO_POINTER (1);
        else
            return GINT_TO_POINTER (0);
    case COL_FLAGGED:
        return GINT_TO_POINTER ((camel_message_info_flags (msg_info) & CAMEL_MESSAGE_FLAGGED) != 0);
    case COL_SCORE: {
        const gchar *tag;
        gint score = 0;

        tag = camel_message_info_user_tag (msg_info, "score");
        if (tag)
            score = atoi (tag);

        return GINT_TO_POINTER (score);
    }
    case COL_FOLLOWUP_FLAG_STATUS: {
        const gchar *tag, *cmp;

        /* FIXME: this all should be methods off of message-tag-followup class,
         * FIXME: the tag names should be namespaced :( */
        tag = camel_message_info_user_tag (msg_info, "follow-up");
        cmp = camel_message_info_user_tag (msg_info, "completed-on");
        if (tag && tag[0]) {
            if (cmp && cmp[0])
                return GINT_TO_POINTER (2);
            else
                return GINT_TO_POINTER (1);
        } else
            return GINT_TO_POINTER (0);
    }
    case COL_FOLLOWUP_DUE_BY: {
        const gchar *tag;
        time_t due_by;

        tag = camel_message_info_user_tag (msg_info, "due-by");
        if (tag && *tag) {
            due_by = camel_header_decode_date (tag, NULL);
            return GINT_TO_POINTER (due_by);
        } else {
            return GINT_TO_POINTER (0);
        }
    }
    case COL_FOLLOWUP_FLAG:
        str = camel_message_info_user_tag (msg_info, "follow-up");
        return (gpointer)(str ? str : "");
    case COL_ATTACHMENT:
        if (camel_message_info_user_flag (msg_info, "$has_cal"))
            return GINT_TO_POINTER (2);
        return GINT_TO_POINTER ((camel_message_info_flags (msg_info) & CAMEL_MESSAGE_ATTACHMENTS) != 0);
    case COL_FROM:
        str = camel_message_info_from (msg_info);
        return (gpointer)(str ? str : "");
    case COL_FROM_NORM:
        return (gpointer) get_normalised_string (message_list, msg_info, col);
    case COL_SUBJECT:
        str = camel_message_info_subject (msg_info);
        return (gpointer)(str ? str : "");
    case COL_SUBJECT_TRIMMED:
        str = get_trimmed_subject (msg_info);
        return (gpointer)(str ? str : "");
    case COL_SUBJECT_NORM:
        return (gpointer) get_normalised_string (message_list, msg_info, col);
    case COL_SENT: {
        struct LatestData ld;
        ld.sent = TRUE;
        ld.latest = 0;

        for_node_and_subtree_if_collapsed (message_list, node, msg_info, latest_foreach, &ld);

        return GINT_TO_POINTER (ld.latest);
    }
    case COL_RECEIVED: {
        struct LatestData ld;
        ld.sent = FALSE;
        ld.latest = 0;

        for_node_and_subtree_if_collapsed (message_list, node, msg_info, latest_foreach, &ld);

        return GINT_TO_POINTER (ld.latest);
    }
    case COL_TO:
        str = camel_message_info_to (msg_info);
        return (gpointer)(str ? str : "");
    case COL_TO_NORM:
        return (gpointer) get_normalised_string (message_list, msg_info, col);
    case COL_SIZE:
        return GINT_TO_POINTER (camel_message_info_size (msg_info));
    case COL_DELETED:
        return GINT_TO_POINTER ((camel_message_info_flags (msg_info) & CAMEL_MESSAGE_DELETED) != 0);
    case COL_UNREAD: {
        gboolean saw_unread = FALSE;

        for_node_and_subtree_if_collapsed (message_list, node, msg_info, unread_foreach, &saw_unread);

        return GINT_TO_POINTER (saw_unread);
    }
    case COL_COLOUR: {
        const gchar *colour, *due_by, *completed, *followup;

        /* Priority: colour tag; label tag; important flag; due-by tag */

        /* This is astonisngly poorly written code */

        /* To add to the woes, what color to show when the user choose multiple labels ?
        Don't say that I need to have the new labels[with subject] column visible always */

        colour = NULL;
        due_by = camel_message_info_user_tag (msg_info, "due-by");
        completed = camel_message_info_user_tag (msg_info, "completed-on");
        followup = camel_message_info_user_tag (msg_info, "follow-up");
        if (colour == NULL) {
            /* Get all applicable labels. */
            struct LabelsData ld;

            ld.store = e_mail_ui_session_get_label_store (
                E_MAIL_UI_SESSION (session));
            ld.labels_tag2iter = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, (GDestroyNotify) gtk_tree_iter_free);
            for_node_and_subtree_if_collapsed (message_list, node, msg_info, add_all_labels_foreach, &ld);

            if (g_hash_table_size (ld.labels_tag2iter) == 1) {
                GHashTableIter iter;
                GtkTreeIter *label_defn;
                GdkColor colour_val;
                gchar *colour_alloced;

                /* Extract the single label from the hashtable. */
                g_hash_table_iter_init (&iter, ld.labels_tag2iter);
                g_hash_table_iter_next (&iter, NULL, (gpointer *) &label_defn);

                e_mail_label_list_store_get_color (ld.store, label_defn, &colour_val);

                /* XXX Hack to avoid returning an allocated string. */
                colour_alloced = gdk_color_to_string (&colour_val);
                colour = g_intern_string (colour_alloced);
                g_free (colour_alloced);
            } else if (camel_message_info_flags (msg_info) & CAMEL_MESSAGE_FLAGGED) {
                /* FIXME: extract from the important.xpm somehow. */
                colour = "#A7453E";
            } else if (((followup && *followup) || (due_by && *due_by)) && !(completed && *completed)) {
                time_t now = time (NULL);

                if ((followup && *followup) || now >= camel_header_decode_date (due_by, NULL))
                    colour = "#A7453E";
            }

            g_hash_table_destroy (ld.labels_tag2iter);
        }

        if (!colour)
            colour = camel_message_info_user_tag (msg_info, "color");

        return (gpointer) colour;
    }
    case COL_LOCATION: {
        /* Fixme : freeing memory stuff (mem leaks) */
        CamelStore *store;
        CamelFolder *folder;
        CamelService *service;
        const gchar *store_name;
        const gchar *folder_name;

        folder = message_list->priv->folder;

        if (CAMEL_IS_VEE_FOLDER (folder))
            folder = camel_vee_folder_get_location (
                CAMEL_VEE_FOLDER (folder),
                (CamelVeeMessageInfo *) msg_info, NULL);

        store = camel_folder_get_parent_store (folder);
        folder_name = camel_folder_get_full_name (folder);

        service = CAMEL_SERVICE (store);
        store_name = camel_service_get_display_name (service);

        return g_strdup_printf ("%s : %s", store_name, folder_name);
    }
    case COL_MIXED_RECIPIENTS:
    case COL_RECIPIENTS:{
        str = camel_message_info_to (msg_info);

        return sanitize_recipients (str);
    }
    case COL_MIXED_SENDER:
    case COL_SENDER:{
        gchar **sender_name = NULL;
        str = camel_message_info_from (msg_info);
        if (str && str[0] != '\0') {
            gchar *res;
            sender_name = g_strsplit (str,"<",2);
            res = g_strdup (*sender_name);
            g_strfreev (sender_name);
            return (gpointer)(res);
        }
        else
            return (gpointer)("");
    }
    case COL_LABELS:{
        struct LabelsData ld;
        GString *result = g_string_new ("");

        ld.store = e_mail_ui_session_get_label_store (
            E_MAIL_UI_SESSION (session));
        ld.labels_tag2iter = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, (GDestroyNotify) gtk_tree_iter_free);
        for_node_and_subtree_if_collapsed (message_list, node, msg_info, add_all_labels_foreach, &ld);

        if (g_hash_table_size (ld.labels_tag2iter) > 0) {
            GHashTableIter iter;
            GtkTreeIter *label_defn;

            g_hash_table_iter_init (&iter, ld.labels_tag2iter);
            while (g_hash_table_iter_next (&iter, NULL, (gpointer *) &label_defn)) {
                gchar *label_name, *label_name_clean;

                if (result->len > 0)
                    g_string_append (result, ", ");

                label_name = e_mail_label_list_store_get_name (ld.store, label_defn);
                label_name_clean = e_str_without_underscores (label_name);

                g_string_append (result, label_name_clean);

                g_free (label_name_clean);
                g_free (label_name);
            }
        }

        g_hash_table_destroy (ld.labels_tag2iter);
        return (gpointer) g_string_free (result, FALSE);
    }
    default:
        g_warning ("%s: This shouldn't be reached (col:%d)", G_STRFUNC, col);
        return NULL;
    }
}

static gchar *
filter_date (time_t date)
{
    time_t nowdate = time (NULL);
    time_t yesdate;
    struct tm then, now, yesterday;
    gchar buf[26];
    gboolean done = FALSE;

    if (date == 0)
        return g_strdup (_("?"));

    localtime_r (&date, &then);
    localtime_r (&nowdate, &now);
    if (then.tm_mday == now.tm_mday &&
        then.tm_mon == now.tm_mon &&
        then.tm_year == now.tm_year) {
        e_utf8_strftime_fix_am_pm (buf, 26, _("Today %l:%M %p"), &then);
        done = TRUE;
    }
    if (!done) {
        yesdate = nowdate - 60 * 60 * 24;
        localtime_r (&yesdate, &yesterday);
        if (then.tm_mday == yesterday.tm_mday &&
            then.tm_mon == yesterday.tm_mon &&
            then.tm_year == yesterday.tm_year) {
            e_utf8_strftime_fix_am_pm (buf, 26, _("Yesterday %l:%M %p"), &then);
            done = TRUE;
        }
    }
    if (!done) {
        gint i;
        for (i = 2; i < 7; i++) {
            yesdate = nowdate - 60 * 60 * 24 * i;
            localtime_r (&yesdate, &yesterday);
            if (then.tm_mday == yesterday.tm_mday &&
                then.tm_mon == yesterday.tm_mon &&
                then.tm_year == yesterday.tm_year) {
                e_utf8_strftime_fix_am_pm (buf, 26, _("%a %l:%M %p"), &then);
                done = TRUE;
                break;
            }
        }
    }
    if (!done) {
        if (then.tm_year == now.tm_year) {
            e_utf8_strftime_fix_am_pm (buf, 26, _("%b %d %l:%M %p"), &then);
        } else {
            e_utf8_strftime_fix_am_pm (buf, 26, _("%b %d %Y"), &then);
        }
    }

    return g_strdup (buf);
}

static ECell * create_composite_cell (gint col)
{
    ECell *cell_vbox, *cell_hbox, *cell_sub, *cell_date, *cell_from, *cell_tree, *cell_attach;
    GSettings *settings;
    gchar *fixed_name = NULL;
    gboolean show_email;
    gint alt_col = (col == COL_FROM) ? COL_SENDER : COL_RECIPIENTS;
    gboolean same_font = FALSE;

    settings = g_settings_new ("org.gnome.evolution.mail");
    show_email = g_settings_get_boolean (settings, "show-email");
    same_font = g_settings_get_boolean (settings, "vertical-view-fonts");
    g_object_unref (settings);
    if (!same_font) {
        settings = g_settings_new ("org.gnome.desktop.interface");
        fixed_name = g_settings_get_string (settings, "monospace-font-name");
        g_object_unref (settings);
    }

    cell_vbox = e_cell_vbox_new ();

    cell_hbox = e_cell_hbox_new ();

    /* Exclude the meeting icon. */
    cell_attach = e_cell_toggle_new (attachment_icons, G_N_ELEMENTS (attachment_icons));

    cell_date = e_cell_date_new (NULL, GTK_JUSTIFY_RIGHT);
    e_cell_date_set_format_component (E_CELL_DATE (cell_date), "mail");
    g_object_set (
        cell_date,
        "bold_column", COL_UNREAD,
        "color_column", COL_COLOUR,
        NULL);

    cell_from = e_cell_text_new (NULL, GTK_JUSTIFY_LEFT);
    g_object_set (
        cell_from,
        "bold_column", COL_UNREAD,
        "color_column", COL_COLOUR,
        NULL);

    e_cell_hbox_append (E_CELL_HBOX (cell_hbox), cell_from, show_email ? col : alt_col, 68);
    e_cell_hbox_append (E_CELL_HBOX (cell_hbox), cell_attach, COL_ATTACHMENT, 5);
    e_cell_hbox_append (E_CELL_HBOX (cell_hbox), cell_date, COL_SENT, 27);
    g_object_unref (cell_from);
    g_object_unref (cell_attach);
    g_object_unref (cell_date);

    cell_sub = e_cell_text_new (fixed_name? fixed_name : NULL, GTK_JUSTIFY_LEFT);
    g_object_set (
        cell_sub,
        "color_column", COL_COLOUR,
        NULL);
    cell_tree = e_cell_tree_new (TRUE, cell_sub);
    e_cell_vbox_append (E_CELL_VBOX (cell_vbox), cell_hbox, COL_FROM);
    e_cell_vbox_append (E_CELL_VBOX (cell_vbox), cell_tree, COL_SUBJECT);
    g_object_unref (cell_sub);
    g_object_unref (cell_hbox);
    g_object_unref (cell_tree);

    g_object_set_data (G_OBJECT (cell_vbox), "cell_date", cell_date);
    g_object_set_data (G_OBJECT (cell_vbox), "cell_sub", cell_sub);
    g_object_set_data (G_OBJECT (cell_vbox), "cell_from", cell_from);

    g_free (fixed_name);

    return cell_vbox;
}

static void
composite_cell_set_strike_col (ECell *cell,
                               gint col)
{
    g_object_set (g_object_get_data (G_OBJECT (cell), "cell_date"),  "strikeout_column", col, NULL);
    g_object_set (g_object_get_data (G_OBJECT (cell), "cell_from"),  "strikeout_column", col, NULL);
}

static ETableExtras *
message_list_create_extras (void)
{
    ETableExtras *extras;
    ECell *cell;

    extras = e_table_extras_new ();
    e_table_extras_add_icon_name (extras, "status", "mail-unread");
    e_table_extras_add_icon_name (extras, "score", "stock_score-higher");
    e_table_extras_add_icon_name (extras, "attachment", "mail-attachment");
    e_table_extras_add_icon_name (extras, "flagged", "emblem-important");
    e_table_extras_add_icon_name (extras, "followup", "stock_mail-flag-for-followup");

    e_table_extras_add_compare (extras, "address_compare", address_compare);

    cell = e_cell_toggle_new (
        status_icons, G_N_ELEMENTS (status_icons));
    e_table_extras_add_cell (extras, "render_message_status", cell);
    g_object_unref (cell);

    cell = e_cell_toggle_new (
        attachment_icons, G_N_ELEMENTS (attachment_icons));
    e_table_extras_add_cell (extras, "render_attachment", cell);
    g_object_unref (cell);

    cell = e_cell_toggle_new (
        flagged_icons, G_N_ELEMENTS (flagged_icons));
    e_table_extras_add_cell (extras, "render_flagged", cell);
    g_object_unref (cell);

    cell = e_cell_toggle_new (
        followup_icons, G_N_ELEMENTS (followup_icons));
    e_table_extras_add_cell (extras, "render_flag_status", cell);
    g_object_unref (cell);

    cell = e_cell_toggle_new (
        score_icons, G_N_ELEMENTS (score_icons));
    e_table_extras_add_cell (extras, "render_score", cell);
    g_object_unref (cell);

    /* date cell */
    cell = e_cell_date_new (NULL, GTK_JUSTIFY_LEFT);
    e_cell_date_set_format_component (E_CELL_DATE (cell), "mail");
    g_object_set (
        cell,
        "bold_column", COL_UNREAD,
        "color_column", COL_COLOUR,
        NULL);
    e_table_extras_add_cell (extras, "render_date", cell);
    g_object_unref (cell);

    /* text cell */
    cell = e_cell_text_new (NULL, GTK_JUSTIFY_LEFT);
    g_object_set (
        cell,
        "bold_column", COL_UNREAD,
        "color_column", COL_COLOUR,
        NULL);
    e_table_extras_add_cell (extras, "render_text", cell);
    g_object_unref (cell);

    cell = e_cell_tree_new (TRUE, cell);
    e_table_extras_add_cell (extras, "render_tree", cell);
    g_object_unref (cell);

    /* size cell */
    cell = e_cell_size_new (NULL, GTK_JUSTIFY_RIGHT);
    g_object_set (
        cell,
        "bold_column", COL_UNREAD,
        "color_column", COL_COLOUR,
        NULL);
    e_table_extras_add_cell (extras, "render_size", cell);
    g_object_unref (cell);

    /* Composite cell for wide view */
    cell = create_composite_cell (COL_FROM);
    e_table_extras_add_cell (extras, "render_composite_from", cell);
    g_object_unref (cell);

    cell = create_composite_cell (COL_TO);
    e_table_extras_add_cell (extras, "render_composite_to", cell);
    g_object_unref (cell);

    /* set proper format component for a default 'date' cell renderer */
    cell = e_table_extras_get_cell (extras, "date");
    e_cell_date_set_format_component (E_CELL_DATE (cell), "mail");

    return extras;
}

static void
save_tree_state (MessageList *message_list,
                 CamelFolder *folder)
{
    ETreeTableAdapter *adapter;
    gchar *filename;

    if (folder == NULL)
        return;

    if (message_list->search != NULL && *message_list->search != '\0')
        return;

    adapter = e_tree_get_table_adapter (E_TREE (message_list));

    filename = mail_config_folder_to_cachename (folder, "et-expanded-");
    e_tree_table_adapter_save_expanded_state (adapter, filename);
    g_free (filename);

    message_list->priv->any_row_changed = FALSE;
}

static void
load_tree_state (MessageList *message_list,
                 CamelFolder *folder,
                 xmlDoc *expand_state)
{
    ETreeTableAdapter *adapter;

    if (folder == NULL)
        return;

    adapter = e_tree_get_table_adapter (E_TREE (message_list));

    if (expand_state != NULL) {
        e_tree_table_adapter_load_expanded_state_xml (
            adapter, expand_state);
    } else if (!message_list->search || !*message_list->search) {
        /* only when not searching */
        gchar *filename;

        filename = mail_config_folder_to_cachename (
            folder, "et-expanded-");
        e_tree_table_adapter_load_expanded_state (adapter, filename);
        g_free (filename);
    }

    message_list->priv->any_row_changed = FALSE;
}

void
message_list_save_state (MessageList *message_list)
{
    CamelFolder *folder;

    folder = message_list_ref_folder (message_list);

    if (folder != NULL) {
        save_tree_state (message_list, folder);
        g_object_unref (folder);
    }
}

static void
message_list_setup_etree (MessageList *message_list)
{
    CamelFolder *folder;

    /* Build the spec based on the folder, and possibly
     * from a saved file.   Otherwise, leave default. */

    folder = message_list_ref_folder (message_list);

    if (folder != NULL) {
        gint data = 1;
        ETableItem *item;

        item = e_tree_get_item (E_TREE (message_list));

        g_object_set (message_list, "uniform_row_height", TRUE, NULL);
        g_object_set_data (
            G_OBJECT (((GnomeCanvasItem *) item)->canvas),
            "freeze-cursor", &data);

        /* build based on saved file */
        load_tree_state (message_list, folder, NULL);

        g_object_unref (folder);
    }
}

static void
ml_selection_get (GtkWidget *widget,
                  GtkSelectionData *data,
                  guint info,
                  guint time_stamp,
                  MessageList *message_list)
{
    struct _MLSelection *selection;

    selection = &message_list->priv->clipboard;

    if (selection->uids == NULL)
        return;

    if (info & 2) {
        /* text/plain */
        d (printf ("setting text/plain selection for uids\n"));
        em_utils_selection_set_mailbox (data, selection->folder, selection->uids);
    } else {
        /* x-uid-list */
        d (printf ("setting x-uid-list selection for uids\n"));
        em_utils_selection_set_uidlist (data, selection->folder, selection->uids);
    }
}

static gboolean
ml_selection_clear_event (GtkWidget *widget,
                          GdkEventSelection *event,
                          MessageList *message_list)
{
    MessageListPrivate *p = message_list->priv;

    clear_selection (message_list, &p->clipboard);

    return TRUE;
}

static void
ml_selection_received (GtkWidget *widget,
                       GtkSelectionData *selection_data,
                       guint time,
                       MessageList *message_list)
{
    EMailSession *session;
    CamelFolder *folder;
    GdkAtom target;

    target = gtk_selection_data_get_target (selection_data);

    if (target != gdk_atom_intern ("x-uid-list", FALSE)) {
        d (printf ("Unknown selection received by message-list\n"));
        return;
    }

    folder = message_list_ref_folder (message_list);
    session = message_list_get_session (message_list);

    /* FIXME Not passing a GCancellable or GError here. */
    em_utils_selection_get_uidlist (
        selection_data, session, folder, FALSE, NULL, NULL);

    g_clear_object (&folder);
}

static void
ml_tree_drag_data_get (ETree *tree,
                       gint row,
                       GNode *node,
                       gint col,
                       GdkDragContext *context,
                       GtkSelectionData *data,
                       guint info,
                       guint time,
                       MessageList *message_list)
{
    CamelFolder *folder;
    GPtrArray *uids;

    folder = message_list_ref_folder (message_list);
    uids = message_list_get_selected (message_list);

    if (uids->len > 0) {
        switch (info) {
        case DND_X_UID_LIST:
            em_utils_selection_set_uidlist (data, folder, uids);
            break;
        case DND_TEXT_URI_LIST:
            em_utils_selection_set_urilist (data, folder, uids);
            break;
        }
    }

    g_clear_object (&folder);
    g_ptr_array_unref (uids);
}

/* TODO: merge this with the folder tree stuff via empopup targets */
/* Drop handling */
struct _drop_msg {
    MailMsg base;

    GdkDragContext *context;

    /* Only selection->data and selection->length are valid */
    GtkSelectionData *selection;

    CamelFolder *folder;
    MessageList *message_list;

    guint32 action;
    guint info;

    guint move : 1;
    guint moved : 1;
    guint aborted : 1;
};

static gchar *
ml_drop_async_desc (struct _drop_msg *m)
{
    const gchar *full_name;

    full_name = camel_folder_get_full_name (m->folder);

    if (m->move)
        return g_strdup_printf (_("Moving messages into folder %s"), full_name);
    else
        return g_strdup_printf (_("Copying messages into folder %s"), full_name);
}

static void
ml_drop_async_exec (struct _drop_msg *m,
                    GCancellable *cancellable,
                    GError **error)
{
    EMailSession *session;

    session = message_list_get_session (m->message_list);

    switch (m->info) {
    case DND_X_UID_LIST:
        em_utils_selection_get_uidlist (
            m->selection, session, m->folder,
            m->action == GDK_ACTION_MOVE,
            cancellable, error);
        break;
    case DND_MESSAGE_RFC822:
        em_utils_selection_get_message (m->selection, m->folder);
        break;
    case DND_TEXT_URI_LIST:
        em_utils_selection_get_urilist (m->selection, m->folder);
        break;
    }
}

static void
ml_drop_async_done (struct _drop_msg *m)
{
    gboolean success, delete;

    /* ?? */
    if (m->aborted) {
        success = FALSE;
        delete = FALSE;
    } else {
        success = (m->base.error == NULL);
        delete = success && m->move && !m->moved;
    }

    gtk_drag_finish (m->context, success, delete, GDK_CURRENT_TIME);
}

static void
ml_drop_async_free (struct _drop_msg *m)
{
    g_object_unref (m->context);
    g_object_unref (m->folder);
    g_object_unref (m->message_list);
    gtk_selection_data_free (m->selection);
}

static MailMsgInfo ml_drop_async_info = {
    sizeof (struct _drop_msg),
    (MailMsgDescFunc) ml_drop_async_desc,
    (MailMsgExecFunc) ml_drop_async_exec,
    (MailMsgDoneFunc) ml_drop_async_done,
    (MailMsgFreeFunc) ml_drop_async_free
};

static void
ml_drop_action (struct _drop_msg *m)
{
    m->move = m->action == GDK_ACTION_MOVE;
    mail_msg_unordered_push (m);
}

static void
ml_tree_drag_data_received (ETree *tree,
                            gint row,
                            GNode *node,
                            gint col,
                            GdkDragContext *context,
                            gint x,
                            gint y,
                            GtkSelectionData *selection_data,
                            guint info,
                            guint time,
                            MessageList *message_list)
{
    CamelFolder *folder;
    struct _drop_msg *m;

    if (gtk_selection_data_get_data (selection_data) == NULL)
        return;

    if (gtk_selection_data_get_length (selection_data) == -1)
        return;

    folder = message_list_ref_folder (message_list);
    if (folder == NULL)
        return;

    m = mail_msg_new (&ml_drop_async_info);
    m->context = g_object_ref (context);
    m->folder = g_object_ref (folder);
    m->message_list = g_object_ref (message_list);
    m->action = gdk_drag_context_get_selected_action (context);
    m->info = info;

    /* need to copy, goes away once we exit */
    m->selection = gtk_selection_data_copy (selection_data);

    ml_drop_action (m);

    g_object_unref (folder);
}

struct search_child_struct {
    gboolean found;
    gconstpointer looking_for;
};

static void
search_child_cb (GtkWidget *widget,
                 gpointer data)
{
    struct search_child_struct *search = (struct search_child_struct *) data;

    search->found = search->found || g_direct_equal (widget, search->looking_for);
}

static gboolean
is_tree_widget_children (ETree *tree,
                         gconstpointer widget)
{
    struct search_child_struct search;

    search.found = FALSE;
    search.looking_for = widget;

    gtk_container_foreach (GTK_CONTAINER (tree), search_child_cb, &search);

    return search.found;
}

static gboolean
ml_tree_drag_motion (ETree *tree,
                     GdkDragContext *context,
                     gint x,
                     gint y,
                     guint time,
                     MessageList *message_list)
{
    GList *targets;
    GdkDragAction action, actions = 0;
    GtkWidget *source_widget;

    /* If drop target is name of the account/store
     * and not actual folder, don't allow any action. */
    if (message_list->priv->folder == NULL) {
        gdk_drag_status (context, 0, time);
        return TRUE;
    }

    source_widget = gtk_drag_get_source_widget (context);

    /* If source widget is packed under 'tree', don't allow any action */
    if (is_tree_widget_children (tree, source_widget)) {
        gdk_drag_status (context, 0, time);
        return TRUE;
    }

    if (EM_IS_FOLDER_TREE (source_widget)) {
        EMFolderTree *folder_tree;
        CamelFolder *selected_folder = NULL;
        CamelStore *selected_store;
        gchar *selected_folder_name;
        gboolean has_selection;

        folder_tree = EM_FOLDER_TREE (source_widget);

        has_selection = em_folder_tree_get_selected (
            folder_tree, &selected_store, &selected_folder_name);

        /* Sanity checks */
        g_warn_if_fail (
            (has_selection && selected_store != NULL) ||
            (!has_selection && selected_store == NULL));
        g_warn_if_fail (
            (has_selection && selected_folder_name != NULL) ||
            (!has_selection && selected_folder_name == NULL));

        if (has_selection) {
            selected_folder = camel_store_get_folder_sync (
                selected_store, selected_folder_name,
                CAMEL_STORE_FOLDER_INFO_FAST, NULL, NULL);
            g_object_unref (selected_store);
            g_free (selected_folder_name);
        }

        if (selected_folder == message_list->priv->folder) {
            gdk_drag_status (context, 0, time);
            return TRUE;
        }
    }

    targets = gdk_drag_context_list_targets (context);
    while (targets != NULL) {
        gint i;

        d (printf ("atom drop '%s'\n", gdk_atom_name (targets->data)));
        for (i = 0; i < G_N_ELEMENTS (ml_drag_info); i++)
            if (targets->data == (gpointer) ml_drag_info[i].atom)
                actions |= ml_drag_info[i].actions;

        targets = g_list_next (targets);
    }
    d (printf ("\n"));

    actions &= gdk_drag_context_get_actions (context);
    action = gdk_drag_context_get_suggested_action (context);
    if (action == GDK_ACTION_COPY && (actions & GDK_ACTION_MOVE))
        action = GDK_ACTION_MOVE;

    gdk_drag_status (context, action, time);

    return action != 0;
}

static void
on_model_row_changed (ETableModel *model,
                      gint row,
                      MessageList *message_list)
{
    message_list->priv->any_row_changed = TRUE;
}

static gboolean
ml_tree_sorting_changed (ETreeTableAdapter *adapter,
                         MessageList *message_list)
{
    gboolean group_by_threads;

    g_return_val_if_fail (message_list != NULL, FALSE);

    group_by_threads = message_list_get_group_by_threads (message_list);

    if (group_by_threads && message_list->frozen == 0) {
        if (message_list->thread_tree != NULL) {
            /* free the previous thread_tree to recreate it fully */
            camel_folder_thread_messages_unref (
                message_list->thread_tree);
            message_list->thread_tree = NULL;
        }

        mail_regen_list (message_list, message_list->search, FALSE);

        return TRUE;
    }

    return FALSE;
}

static void
message_list_set_session (MessageList *message_list,
                          EMailSession *session)
{
    g_return_if_fail (E_IS_MAIL_SESSION (session));
    g_return_if_fail (message_list->priv->session == NULL);

    message_list->priv->session = g_object_ref (session);
}

static void
message_list_set_property (GObject *object,
                           guint property_id,
                           const GValue *value,
                           GParamSpec *pspec)
{
    switch (property_id) {
        case PROP_FOLDER:
            message_list_set_folder (
                MESSAGE_LIST (object),
                g_value_get_object (value));
            return;

        case PROP_GROUP_BY_THREADS:
            message_list_set_group_by_threads (
                MESSAGE_LIST (object),
                g_value_get_boolean (value));
            return;

        case PROP_SESSION:
            message_list_set_session (
                MESSAGE_LIST (object),
                g_value_get_object (value));
            return;

        case PROP_SHOW_DELETED:
            message_list_set_show_deleted (
                MESSAGE_LIST (object),
                g_value_get_boolean (value));
            return;

        case PROP_THREAD_LATEST:
            message_list_set_thread_latest (
                MESSAGE_LIST (object),
                g_value_get_boolean (value));
            return;

        case PROP_THREAD_SUBJECT:
            message_list_set_thread_subject (
                MESSAGE_LIST (object),
                g_value_get_boolean (value));
            return;
    }

    G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
}

static void
message_list_get_property (GObject *object,
                           guint property_id,
                           GValue *value,
                           GParamSpec *pspec)
{
    switch (property_id) {
        case PROP_COPY_TARGET_LIST:
            g_value_set_boxed (
                value,
                message_list_get_copy_target_list (
                MESSAGE_LIST (object)));
            return;

        case PROP_FOLDER:
            g_value_take_object (
                value,
                message_list_ref_folder (
                MESSAGE_LIST (object)));
            return;

        case PROP_GROUP_BY_THREADS:
            g_value_set_boolean (
                value,
                message_list_get_group_by_threads (
                MESSAGE_LIST (object)));
            return;

        case PROP_PASTE_TARGET_LIST:
            g_value_set_boxed (
                value,
                message_list_get_paste_target_list (
                MESSAGE_LIST (object)));
            return;

        case PROP_SESSION:
            g_value_set_object (
                value,
                message_list_get_session (
                MESSAGE_LIST (object)));
            return;

        case PROP_SHOW_DELETED:
            g_value_set_boolean (
                value,
                message_list_get_show_deleted (
                MESSAGE_LIST (object)));
            return;

        case PROP_THREAD_LATEST:
            g_value_set_boolean (
                value,
                message_list_get_thread_latest (
                MESSAGE_LIST (object)));
            return;

        case PROP_THREAD_SUBJECT:
            g_value_set_boolean (
                value,
                message_list_get_thread_subject (
                MESSAGE_LIST (object)));
            return;
    }

    G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
}

static void
message_list_dispose (GObject *object)
{
    MessageList *message_list = MESSAGE_LIST (object);
    MessageListPrivate *priv;

    priv = message_list->priv;

    if (priv->folder_changed_handler_id > 0) {
        g_signal_handler_disconnect (
            priv->folder,
            priv->folder_changed_handler_id);
        priv->folder_changed_handler_id = 0;
    }

    if (priv->copy_target_list != NULL) {
        gtk_target_list_unref (priv->copy_target_list);
        priv->copy_target_list = NULL;
    }

    if (priv->paste_target_list != NULL) {
        gtk_target_list_unref (priv->paste_target_list);
        priv->paste_target_list = NULL;
    }

    priv->destroyed = TRUE;

    if (message_list->priv->folder != NULL)
        mail_regen_cancel (message_list);

    if (message_list->uid_nodemap) {
        g_hash_table_foreach (
            message_list->uid_nodemap,
            (GHFunc) clear_info, message_list);
        g_hash_table_destroy (message_list->uid_nodemap);
        message_list->uid_nodemap = NULL;
    }

    g_clear_object (&priv->session);
    g_clear_object (&priv->folder);
    g_clear_object (&priv->invisible);

    g_clear_object (&message_list->extras);

    if (message_list->idle_id > 0) {
        g_source_remove (message_list->idle_id);
        message_list->idle_id = 0;
    }

    if (message_list->seen_id > 0) {
        g_source_remove (message_list->seen_id);
        message_list->seen_id = 0;
    }

    /* Chain up to parent's dispose() method. */
    G_OBJECT_CLASS (message_list_parent_class)->dispose (object);
}

static void
message_list_finalize (GObject *object)
{
    MessageList *message_list = MESSAGE_LIST (object);

    g_hash_table_destroy (message_list->normalised_hash);

    if (message_list->thread_tree)
        camel_folder_thread_messages_unref (message_list->thread_tree);

    g_free (message_list->search);
    g_free (message_list->frozen_search);
    g_free (message_list->cursor_uid);

    g_mutex_clear (&message_list->priv->regen_lock);

    clear_selection (message_list, &message_list->priv->clipboard);

    if (message_list->priv->tree_model_root != NULL)
        g_node_destroy (message_list->priv->tree_model_root);

    /* Chain up to parent's finalize() method. */
    G_OBJECT_CLASS (message_list_parent_class)->finalize (object);
}

static void
message_list_constructed (GObject *object)
{
    /* Chain up to parent's constructed() method. */
    G_OBJECT_CLASS (message_list_parent_class)->constructed (object);

    e_extensible_load_extensions (E_EXTENSIBLE (object));
}

static void
message_list_selectable_update_actions (ESelectable *selectable,
                                        EFocusTracker *focus_tracker,
                                        GdkAtom *clipboard_targets,
                                        gint n_clipboard_targets)
{
    GtkAction *action;
    gboolean sensitive;

    action = e_focus_tracker_get_select_all_action (focus_tracker);
    sensitive = (e_tree_row_count (E_TREE (selectable)) > 0);
    gtk_action_set_tooltip (action, _("Select all visible messages"));
    gtk_action_set_sensitive (action, sensitive);
}

static void
message_list_selectable_select_all (ESelectable *selectable)
{
    message_list_select_all (MESSAGE_LIST (selectable));
}

static ETreePath
message_list_get_root (ETreeModel *tree_model)
{
    MessageList *message_list = MESSAGE_LIST (tree_model);

    return message_list->priv->tree_model_root;
}

static ETreePath
message_list_get_parent (ETreeModel *tree_model,
                         ETreePath path)
{
    return ((GNode *) path)->parent;
}

static ETreePath
message_list_get_first_child (ETreeModel *tree_model,
                              ETreePath path)
{
    return g_node_first_child ((GNode *) path);
}

static ETreePath
message_list_get_next (ETreeModel *tree_model,
                       ETreePath path)
{
    return g_node_next_sibling ((GNode *) path);
}

static gboolean
message_list_is_root (ETreeModel *tree_model,
                      ETreePath path)
{
    return G_NODE_IS_ROOT ((GNode *) path);
}

static gboolean
message_list_is_expandable (ETreeModel *tree_model,
                            ETreePath path)
{
    return (g_node_first_child ((GNode *) path) != NULL);
}

static guint
message_list_get_n_nodes (ETreeModel *tree_model)
{
    ETreePath root;

    root = e_tree_model_get_root (tree_model);

    if (root == NULL)
        return 0;

    /* The root node is an empty placeholder, so
     * subtract one from the count to exclude it. */

    return g_node_n_nodes ((GNode *) root, G_TRAVERSE_ALL) - 1;
}

static guint
message_list_get_n_children (ETreeModel *tree_model,
                             ETreePath path)
{
    return g_node_n_children ((GNode *) path);
}

static guint
message_list_depth (ETreeModel *tree_model,
                    ETreePath path)
{
    return g_node_depth ((GNode *) path);
}

static gboolean
message_list_get_expanded_default (ETreeModel *tree_model)
{
    MessageList *message_list = MESSAGE_LIST (tree_model);

    return message_list->priv->expanded_default;
}

static gint
message_list_column_count (ETreeModel *tree_model)
{
    return COL_LAST;
}

static gchar *
message_list_get_save_id (ETreeModel *tree_model,
                          ETreePath path)
{
    CamelMessageInfo *info;

    if (G_NODE_IS_ROOT ((GNode *) path))
        return g_strdup ("root");

    /* Note: ETable can ask for the save_id while we're clearing
     *       it, which is the only time info should be NULL. */
    info = ((GNode *) path)->data;
    if (info == NULL)
        return NULL;

    return g_strdup (camel_message_info_uid (info));
}

static ETreePath
message_list_get_node_by_id (ETreeModel *tree_model,
                             const gchar *save_id)
{
    MessageList *message_list;

    message_list = MESSAGE_LIST (tree_model);

    if (!strcmp (save_id, "root"))
        return e_tree_model_get_root (tree_model);

    return g_hash_table_lookup (message_list->uid_nodemap, save_id);
}

static gpointer
message_list_sort_value_at (ETreeModel *tree_model,
                            ETreePath path,
                            gint col)
{
    MessageList *message_list;
    struct LatestData ld;

    message_list = MESSAGE_LIST (tree_model);

    if (!(col == COL_SENT || col == COL_RECEIVED))
        return e_tree_model_value_at (tree_model, path, col);

    if (G_NODE_IS_ROOT ((GNode *) path))
        return NULL;

    ld.sent = (col == COL_SENT);
    ld.latest = 0;

    latest_foreach (tree_model, path, &ld);
    if (message_list->priv->thread_latest)
        e_tree_model_node_traverse (
            tree_model, path, latest_foreach, &ld);

    return GINT_TO_POINTER (ld.latest);
}

static gpointer
message_list_value_at (ETreeModel *tree_model,
                       ETreePath path,
                       gint col)
{
    MessageList *message_list;
    CamelMessageInfo *msg_info;

    message_list = MESSAGE_LIST (tree_model);

    if (G_NODE_IS_ROOT ((GNode *) path))
        return NULL;

    /* retrieve the message information array */
    msg_info = ((GNode *) path)->data;
    g_return_val_if_fail (msg_info != NULL, NULL);

    return ml_tree_value_at_ex (tree_model, path, col, msg_info, message_list);
}

static gpointer
message_list_duplicate_value (ETreeModel *tree_model,
                              gint col,
                              gconstpointer value)
{
    switch (col) {
        case COL_MESSAGE_STATUS:
        case COL_FLAGGED:
        case COL_SCORE:
        case COL_ATTACHMENT:
        case COL_DELETED:
        case COL_UNREAD:
        case COL_SENT:
        case COL_RECEIVED:
        case COL_SIZE:
        case COL_FOLLOWUP_FLAG_STATUS:
        case COL_FOLLOWUP_DUE_BY:
            return (gpointer) value;

        case COL_FROM:
        case COL_SUBJECT:
        case COL_TO:
        case COL_SENDER:
        case COL_RECIPIENTS:
        case COL_MIXED_SENDER:
        case COL_MIXED_RECIPIENTS:
        case COL_FOLLOWUP_FLAG:
        case COL_LOCATION:
        case COL_LABELS:
            return g_strdup (value);

        default:
            g_return_val_if_reached (NULL);
    }
}

static void
message_list_free_value (ETreeModel *tree_model,
                         gint col,
                         gpointer value)
{
    switch (col) {
        case COL_MESSAGE_STATUS:
        case COL_FLAGGED:
        case COL_SCORE:
        case COL_ATTACHMENT:
        case COL_DELETED:
        case COL_UNREAD:
        case COL_SENT:
        case COL_RECEIVED:
        case COL_SIZE:
        case COL_FOLLOWUP_FLAG_STATUS:
        case COL_FOLLOWUP_DUE_BY:
        case COL_FROM_NORM:
        case COL_SUBJECT_NORM:
        case COL_TO_NORM:
        case COL_SUBJECT_TRIMMED:
        case COL_COLOUR:
            break;

        case COL_FROM:
        case COL_SUBJECT:
        case COL_TO:
        case COL_FOLLOWUP_FLAG:
        case COL_LOCATION:
        case COL_SENDER:
        case COL_RECIPIENTS:
        case COL_MIXED_SENDER:
        case COL_MIXED_RECIPIENTS:
        case COL_LABELS:
            g_free (value);
            break;

        default:
            g_warn_if_reached ();
    }
}

static gpointer
message_list_initialize_value (ETreeModel *tree_model,
                               gint col)
{
    switch (col) {
        case COL_MESSAGE_STATUS:
        case COL_FLAGGED:
        case COL_SCORE:
        case COL_ATTACHMENT:
        case COL_DELETED:
        case COL_UNREAD:
        case COL_SENT:
        case COL_RECEIVED:
        case COL_SIZE:
        case COL_FOLLOWUP_FLAG_STATUS:
        case COL_FOLLOWUP_DUE_BY:
            return NULL;

        case COL_FROM:
        case COL_SUBJECT:
        case COL_TO:
        case COL_FOLLOWUP_FLAG:
        case COL_LOCATION:
        case COL_SENDER:
        case COL_RECIPIENTS:
        case COL_MIXED_SENDER:
        case COL_MIXED_RECIPIENTS:
        case COL_LABELS:
            return g_strdup ("");

        default:
            g_return_val_if_reached (NULL);
    }
}

static gboolean
message_list_value_is_empty (ETreeModel *tree_model,
                             gint col,
                             gconstpointer value)
{
    switch (col) {
        case COL_MESSAGE_STATUS:
        case COL_FLAGGED:
        case COL_SCORE:
        case COL_ATTACHMENT:
        case COL_DELETED:
        case COL_UNREAD:
        case COL_SENT:
        case COL_RECEIVED:
        case COL_SIZE:
        case COL_FOLLOWUP_FLAG_STATUS:
        case COL_FOLLOWUP_DUE_BY:
            return value == NULL;

        case COL_FROM:
        case COL_SUBJECT:
        case COL_TO:
        case COL_FOLLOWUP_FLAG:
        case COL_LOCATION:
        case COL_SENDER:
        case COL_RECIPIENTS:
        case COL_MIXED_SENDER:
        case COL_MIXED_RECIPIENTS:
        case COL_LABELS:
            return !(value && *(gchar *) value);

        default:
            g_return_val_if_reached (FALSE);
    }
}

static gchar *
message_list_value_to_string (ETreeModel *tree_model,
                              gint col,
                              gconstpointer value)
{
    guint ii;

    switch (col) {
        case COL_MESSAGE_STATUS:
            ii = GPOINTER_TO_UINT (value);
            if (ii > 5)
                return g_strdup ("");
            return g_strdup (_(status_map[ii]));

        case COL_SCORE:
            ii = GPOINTER_TO_UINT (value) + 3;
            if (ii > 6)
                ii = 3;
            return g_strdup (_(score_map[ii]));

        case COL_ATTACHMENT:
        case COL_FLAGGED:
        case COL_DELETED:
        case COL_UNREAD:
        case COL_FOLLOWUP_FLAG_STATUS:
            ii = GPOINTER_TO_UINT (value);
            return g_strdup_printf ("%u", ii);

        case COL_SENT:
        case COL_RECEIVED:
        case COL_FOLLOWUP_DUE_BY:
            return filter_date (GPOINTER_TO_INT (value));

        case COL_SIZE:
            return filter_size (GPOINTER_TO_INT (value));

        case COL_FROM:
        case COL_SUBJECT:
        case COL_TO:
        case COL_FOLLOWUP_FLAG:
        case COL_LOCATION:
        case COL_SENDER:
        case COL_RECIPIENTS:
        case COL_MIXED_SENDER:
        case COL_MIXED_RECIPIENTS:
        case COL_LABELS:
            return g_strdup (value);

        default:
            g_return_val_if_reached (NULL);
    }

}

static void
message_list_class_init (MessageListClass *class)
{
    GObjectClass *object_class;
    gint i;

    for (i = 0; i < G_N_ELEMENTS (ml_drag_info); i++)
        ml_drag_info[i].atom = gdk_atom_intern (ml_drag_info[i].target, FALSE);

    g_type_class_add_private (class, sizeof (MessageListPrivate));

    object_class = G_OBJECT_CLASS (class);
    object_class->set_property = message_list_set_property;
    object_class->get_property = message_list_get_property;
    object_class->dispose = message_list_dispose;
    object_class->finalize = message_list_finalize;
    object_class->constructed = message_list_constructed;

    class->message_list_built = NULL;

    /* Inherited from ESelectableInterface */
    g_object_class_override_property (
        object_class,
        PROP_COPY_TARGET_LIST,
        "copy-target-list");

    g_object_class_install_property (
        object_class,
        PROP_FOLDER,
        g_param_spec_object (
            "folder",
            "Folder",
            "The source folder",
            CAMEL_TYPE_FOLDER,
            G_PARAM_READWRITE |
            G_PARAM_STATIC_STRINGS));

    g_object_class_install_property (
        object_class,
        PROP_GROUP_BY_THREADS,
        g_param_spec_boolean (
            "group-by-threads",
            "Group By Threads",
            "Group messages into conversation threads",
            FALSE,
            G_PARAM_READWRITE |
            G_PARAM_CONSTRUCT |
            G_PARAM_STATIC_STRINGS));

    /* Inherited from ESelectableInterface */
    g_object_class_override_property (
        object_class,
        PROP_PASTE_TARGET_LIST,
        "paste-target-list");

    g_object_class_install_property (
        object_class,
        PROP_SESSION,
        g_param_spec_object (
            "session",
            "Mail Session",
            "The mail session",
            E_TYPE_MAIL_SESSION,
            G_PARAM_READWRITE |
            G_PARAM_CONSTRUCT_ONLY |
            G_PARAM_STATIC_STRINGS));

    g_object_class_install_property (
        object_class,
        PROP_SHOW_DELETED,
        g_param_spec_boolean (
            "show-deleted",
            "Show Deleted",
            "Show messages marked for deletion",
            FALSE,
            G_PARAM_READWRITE |
            G_PARAM_CONSTRUCT |
            G_PARAM_STATIC_STRINGS));

    g_object_class_install_property (
        object_class,
        PROP_THREAD_LATEST,
        g_param_spec_boolean (
            "thread-latest",
            "Thread Latest",
            "Sort threads by latest message",
            TRUE,
            G_PARAM_READWRITE |
            G_PARAM_CONSTRUCT |
            G_PARAM_STATIC_STRINGS));

    g_object_class_install_property (
        object_class,
        PROP_THREAD_SUBJECT,
        g_param_spec_boolean (
            "thread-subject",
            "Thread Subject",
            "Thread messages by Subject headers",
            FALSE,
            G_PARAM_READWRITE |
            G_PARAM_CONSTRUCT |
            G_PARAM_STATIC_STRINGS));

    signals[MESSAGE_SELECTED] = g_signal_new (
        "message_selected",
        MESSAGE_LIST_TYPE,
        G_SIGNAL_RUN_LAST,
        G_STRUCT_OFFSET (MessageListClass, message_selected),
        NULL,
        NULL,
        g_cclosure_marshal_VOID__STRING,
        G_TYPE_NONE, 1,
        G_TYPE_STRING);

    signals[MESSAGE_LIST_BUILT] = g_signal_new (
        "message_list_built",
        MESSAGE_LIST_TYPE,
        G_SIGNAL_RUN_LAST,
        G_STRUCT_OFFSET (MessageListClass, message_list_built),
        NULL,
        NULL,
        g_cclosure_marshal_VOID__VOID,
        G_TYPE_NONE, 0);
}

static void
message_list_selectable_init (ESelectableInterface *interface)
{
    interface->update_actions = message_list_selectable_update_actions;
    interface->select_all = message_list_selectable_select_all;
}

static void
message_list_tree_model_init (ETreeModelInterface *interface)
{
    interface->get_root = message_list_get_root;
    interface->get_parent = message_list_get_parent;
    interface->get_first_child = message_list_get_first_child;
    interface->get_next = message_list_get_next;
    interface->is_root = message_list_is_root;
    interface->is_expandable = message_list_is_expandable;
    interface->get_n_nodes = message_list_get_n_nodes;
    interface->get_n_children = message_list_get_n_children;
    interface->depth = message_list_depth;
    interface->get_expanded_default = message_list_get_expanded_default;
    interface->column_count = message_list_column_count;
    interface->get_save_id = message_list_get_save_id;
    interface->get_node_by_id = message_list_get_node_by_id;
    interface->sort_value_at = message_list_sort_value_at;
    interface->value_at = message_list_value_at;
    interface->duplicate_value = message_list_duplicate_value;
    interface->free_value = message_list_free_value;
    interface->initialize_value = message_list_initialize_value;
    interface->value_is_empty = message_list_value_is_empty;
    interface->value_to_string = message_list_value_to_string;
}

static void
message_list_init (MessageList *message_list)
{
    MessageListPrivate *p;
    GtkTargetList *target_list;
    GdkAtom matom;

    message_list->priv = MESSAGE_LIST_GET_PRIVATE (message_list);

    message_list->normalised_hash = g_hash_table_new_full (
        g_str_hash, g_str_equal,
        (GDestroyNotify) NULL,
        (GDestroyNotify) e_poolv_destroy);

    message_list->uid_nodemap = g_hash_table_new (g_str_hash, g_str_equal);

    message_list->cursor_uid = NULL;
    message_list->last_sel_single = FALSE;

    g_mutex_init (&message_list->priv->regen_lock);

    /* TODO: Should this only get the selection if we're realised? */
    p = message_list->priv;
    p->invisible = gtk_invisible_new ();
    p->destroyed = FALSE;
    g_object_ref_sink (p->invisible);
    p->any_row_changed = FALSE;

    matom = gdk_atom_intern ("x-uid-list", FALSE);
    gtk_selection_add_target (p->invisible, GDK_SELECTION_CLIPBOARD, matom, 0);
    gtk_selection_add_target (p->invisible, GDK_SELECTION_CLIPBOARD, GDK_SELECTION_TYPE_STRING, 2);

    g_signal_connect (
        p->invisible, "selection_get",
        G_CALLBACK (ml_selection_get), message_list);
    g_signal_connect (
        p->invisible, "selection_clear_event",
        G_CALLBACK (ml_selection_clear_event), message_list);
    g_signal_connect (
        p->invisible, "selection_received",
        G_CALLBACK (ml_selection_received), message_list);

    /* FIXME This is currently unused. */
    target_list = gtk_target_list_new (NULL, 0);
    message_list->priv->copy_target_list = target_list;

    /* FIXME This is currently unused. */
    target_list = gtk_target_list_new (NULL, 0);
    message_list->priv->paste_target_list = target_list;
}

static void
message_list_construct (MessageList *message_list)
{
    ETreeTableAdapter *adapter;
    AtkObject *a11y;
    gboolean constructed;
    gchar *etspecfile;

    /*
     * The etree
     */
    message_list->extras = message_list_create_extras ();

    etspecfile = g_build_filename (EVOLUTION_ETSPECDIR, "message-list.etspec", NULL);
    constructed = e_tree_construct_from_spec_file (
        E_TREE (message_list),
        E_TREE_MODEL (message_list),
        message_list->extras, etspecfile, NULL);
    g_free (etspecfile);

    adapter = e_tree_get_table_adapter (E_TREE (message_list));

    if (constructed)
        e_tree_table_adapter_root_node_set_visible (adapter, FALSE);

    if (atk_get_root () != NULL) {
        a11y = gtk_widget_get_accessible (GTK_WIDGET (message_list));
        atk_object_set_name (a11y, _("Messages"));
    }

    g_signal_connect (
        adapter, "model_row_changed",
        G_CALLBACK (on_model_row_changed), message_list);

    g_signal_connect (
        message_list, "cursor_activated",
        G_CALLBACK (on_cursor_activated_cmd), message_list);

    g_signal_connect (
        message_list, "click",
        G_CALLBACK (on_click), message_list);

    g_signal_connect (
        message_list, "selection_change",
        G_CALLBACK (on_selection_changed_cmd), message_list);

    e_tree_drag_source_set (
        E_TREE (message_list), GDK_BUTTON1_MASK,
        ml_drag_types, G_N_ELEMENTS (ml_drag_types),
        GDK_ACTION_MOVE | GDK_ACTION_COPY);

    g_signal_connect (
        message_list, "tree_drag_data_get",
        G_CALLBACK (ml_tree_drag_data_get), message_list);

    gtk_drag_dest_set (
        GTK_WIDGET (message_list),
        GTK_DEST_DEFAULT_ALL,
        ml_drop_types,
        G_N_ELEMENTS (ml_drop_types),
        GDK_ACTION_MOVE |
        GDK_ACTION_COPY);

    g_signal_connect (
        message_list, "tree_drag_data_received",
        G_CALLBACK (ml_tree_drag_data_received), message_list);

    g_signal_connect (
        message_list, "drag-motion",
        G_CALLBACK (ml_tree_drag_motion), message_list);

    g_signal_connect (
        adapter, "sorting_changed",
        G_CALLBACK (ml_tree_sorting_changed), message_list);
}

/**
 * message_list_new:
 *
 * Creates a new message-list widget.
 *
 * Returns a new message-list widget.
 **/
GtkWidget *
message_list_new (EMailSession *session)
{
    GtkWidget *message_list;

    g_return_val_if_fail (E_IS_MAIL_SESSION (session), NULL);

    message_list = g_object_new (
        message_list_get_type (),
        "session", session, NULL);

    message_list_construct (MESSAGE_LIST (message_list));

    return message_list;
}

EMailSession *
message_list_get_session (MessageList *message_list)
{
    g_return_val_if_fail (IS_MESSAGE_LIST (message_list), NULL);

    return message_list->priv->session;
}

static void
clear_info (gchar *key,
            GNode *node,
            MessageList *message_list)
{
    CamelMessageInfo *info;

    info = node->data;
    camel_folder_free_message_info (message_list->priv->folder, info);
    node->data = NULL;
}

static void
clear_tree (MessageList *message_list,
            gboolean tfree)
{
    ETreeModel *tree_model;
    CamelFolder *folder;

#ifdef TIMEIT
    struct timeval start, end;
    gulong diff;

    printf ("Clearing tree\n");
    gettimeofday (&start, NULL);
#endif

    tree_model = E_TREE_MODEL (message_list);

    /* we also reset the uid_rowmap since it is no longer useful/valid anyway */
    folder = message_list_ref_folder (message_list);
    if (folder != NULL)
        g_hash_table_foreach (
            message_list->uid_nodemap,
            (GHFunc) clear_info, message_list);
    g_hash_table_destroy (message_list->uid_nodemap);
    message_list->uid_nodemap = g_hash_table_new (g_str_hash, g_str_equal);
    g_clear_object (&folder);

    message_list->priv->newest_read_date = 0;
    message_list->priv->newest_read_uid = NULL;
    message_list->priv->oldest_unread_date = 0;
    message_list->priv->oldest_unread_uid = NULL;

    if (message_list->priv->tree_model_root != NULL) {
        /* we should be frozen already */
        message_list_tree_model_remove (
            message_list, message_list->priv->tree_model_root);
    }

    /* Create a new placeholder root node. */
    message_list_tree_model_insert (message_list, NULL, 0, NULL);
    g_warn_if_fail (message_list->priv->tree_model_root != NULL);

    if (tfree)
        e_tree_model_rebuilt (tree_model);
#ifdef TIMEIT
    gettimeofday (&end, NULL);
    diff = end.tv_sec * 1000 + end.tv_usec / 1000;
    diff -= start.tv_sec * 1000 + start.tv_usec / 1000;
    printf ("Clearing tree took %ld.%03ld seconds\n", diff / 1000, diff % 1000);
#endif
}

static gboolean
folder_store_supports_vjunk_folder (CamelFolder *folder)
{
    CamelStore *store;

    g_return_val_if_fail (folder != NULL, FALSE);

    store = camel_folder_get_parent_store (folder);
    if (store == NULL)
        return FALSE;

    if (CAMEL_IS_VEE_FOLDER (folder))
        return TRUE;

    if (store->flags & CAMEL_STORE_VJUNK)
        return TRUE;

    if (store->flags & CAMEL_STORE_REAL_JUNK_FOLDER)
        return TRUE;

    return FALSE;
}

static gboolean
message_list_get_hide_junk (MessageList *message_list,
                            CamelFolder *folder)
{
    if (folder == NULL)
        return FALSE;

    if (!folder_store_supports_vjunk_folder (folder))
        return FALSE;

    if (folder->folder_flags & CAMEL_FOLDER_IS_JUNK)
        return FALSE;

    if (folder->folder_flags & CAMEL_FOLDER_IS_TRASH)
        return FALSE;

    return TRUE;
}

static gboolean
message_list_get_hide_deleted (MessageList *message_list,
                               CamelFolder *folder)
{
    CamelStore *store;
    gboolean non_trash_folder;

    if (folder == NULL)
        return FALSE;

    if (message_list_get_show_deleted (message_list))
        return FALSE;

    store = camel_folder_get_parent_store (folder);
    g_return_val_if_fail (store != NULL, FALSE);

    non_trash_folder =
        ((store->flags & CAMEL_STORE_VTRASH) == 0) ||
        ((folder->folder_flags & CAMEL_FOLDER_IS_TRASH) == 0);

    return non_trash_folder;
}

/* Check if the given node is selectable in the current message list,
 * which depends on the type of the folder (normal, junk, trash). */
static gboolean
is_node_selectable (MessageList *message_list,
                    CamelMessageInfo *info)
{
    CamelFolder *folder;
    gboolean is_junk_folder;
    gboolean is_trash_folder;
    guint32 flags;
    gboolean flag_junk;
    gboolean flag_deleted;
    gboolean hide_junk;
    gboolean hide_deleted;
    gboolean store_has_vjunk;
    gboolean selectable = FALSE;

    g_return_val_if_fail (info != NULL, FALSE);

    folder = message_list_ref_folder (message_list);
    g_return_val_if_fail (folder != NULL, FALSE);

    store_has_vjunk = folder_store_supports_vjunk_folder (folder);

    /* check folder type */
    is_junk_folder =
        store_has_vjunk &&
        (folder->folder_flags & CAMEL_FOLDER_IS_JUNK) != 0;
    is_trash_folder = folder->folder_flags & CAMEL_FOLDER_IS_TRASH;

    hide_junk = message_list_get_hide_junk (message_list, folder);
    hide_deleted = message_list_get_hide_deleted (message_list, folder);

    g_object_unref (folder);

    /* check flags set on current message */
    flags = camel_message_info_flags (info);
    flag_junk = store_has_vjunk && (flags & CAMEL_MESSAGE_JUNK) != 0;
    flag_deleted = flags & CAMEL_MESSAGE_DELETED;

    /* perform actions depending on folder type */
    if (is_junk_folder) {
        /* messages in a junk folder are selectable only if
         * the message is marked as junk and if not deleted
         * when hide_deleted is set */
        if (flag_junk && !(flag_deleted && hide_deleted))
            selectable = TRUE;

    } else if (is_trash_folder) {
        /* messages in a trash folder are selectable unless
         * not deleted any more */
        if (flag_deleted)
            selectable = TRUE;
    } else {
        /* in normal folders it depends on hide_deleted,
         * hide_junk and the message flags */
        if (!(flag_junk && hide_junk)
            && !(flag_deleted && hide_deleted))
            selectable = TRUE;
    }

    return selectable;
}

/* We try and find something that is selectable in our tree.  There is
 * actually no assurance that we'll find something that will still be
 * there next time, but its probably going to work most of the time. */
static gchar *
find_next_selectable (MessageList *message_list)
{
    ETreeTableAdapter *adapter;
    GNode *node;
    gint last;
    gint vrow_orig;
    gint vrow;
    ETree *et = E_TREE (message_list);
    CamelMessageInfo *info;

    adapter = e_tree_get_table_adapter (E_TREE (message_list));

    node = g_hash_table_lookup (
        message_list->uid_nodemap, message_list->cursor_uid);
    if (node == NULL)
        return NULL;

    info = get_message_info (message_list, node);
    if (info && is_node_selectable (message_list, info))
        return NULL;

    last = e_tree_row_count (et);

    /* model_to_view_row etc simply dont work for sorted views.  Sigh. */
    vrow_orig = e_tree_table_adapter_row_of_node (adapter, node);

    /* We already checked this node. */
    vrow = vrow_orig + 1;

    while (vrow < last) {
        node = e_tree_table_adapter_node_at_row (adapter, vrow);
        info = get_message_info (message_list, node);
        if (info && is_node_selectable (message_list, info))
            return g_strdup (camel_message_info_uid (info));
        vrow++;
    }

    /* We didn't find any undeleted entries _below_ the currently selected one
 *       * so let's try to find one _above_ */
    vrow = vrow_orig - 1;

    while (vrow >= 0) {
        node = e_tree_table_adapter_node_at_row (adapter, vrow);
        info = get_message_info (message_list, node);
        if (info && is_node_selectable (message_list, info))
            return g_strdup (camel_message_info_uid (info));
        vrow--;
    }

    return NULL;
}

static GNode *
ml_uid_nodemap_insert (MessageList *message_list,
                       CamelMessageInfo *info,
                       GNode *parent,
                       gint row)
{
    CamelFolder *folder;
    GNode *node;
    const gchar *uid;
    time_t date;
    guint flags;

    folder = message_list_ref_folder (message_list);
    g_return_val_if_fail (folder != NULL, NULL);

    if (parent == NULL)
        parent = message_list->priv->tree_model_root;

    node = message_list_tree_model_insert (
        message_list, parent, row, info);

    uid = camel_message_info_uid (info);
    flags = camel_message_info_flags (info);
    date = camel_message_info_date_received (info);

    camel_folder_ref_message_info (folder, info);
    g_hash_table_insert (message_list->uid_nodemap, (gpointer) uid, node);

    /* Track the latest seen and unseen messages shown, used in
     * fallback heuristics for automatic message selection. */
    if (flags & CAMEL_MESSAGE_SEEN) {
        if (date > message_list->priv->newest_read_date) {
            message_list->priv->newest_read_date = date;
            message_list->priv->newest_read_uid = uid;
        }
    } else {
        if (message_list->priv->oldest_unread_date == 0) {
            message_list->priv->oldest_unread_date = date;
            message_list->priv->oldest_unread_uid = uid;
        } else if (date < message_list->priv->oldest_unread_date) {
            message_list->priv->oldest_unread_date = date;
            message_list->priv->oldest_unread_uid = uid;
        }
    }

    g_object_unref (folder);

    return node;
}

static void
ml_uid_nodemap_remove (MessageList *message_list,
                       CamelMessageInfo *info)
{
    CamelFolder *folder;
    const gchar *uid;

    folder = message_list_ref_folder (message_list);
    g_return_if_fail (folder != NULL);

    uid = camel_message_info_uid (info);

    if (uid == message_list->priv->newest_read_uid) {
        message_list->priv->newest_read_date = 0;
        message_list->priv->newest_read_uid = NULL;
    }

    if (uid == message_list->priv->oldest_unread_uid) {
        message_list->priv->oldest_unread_date = 0;
        message_list->priv->oldest_unread_uid = NULL;
    }

    g_hash_table_remove (message_list->uid_nodemap, uid);
    camel_folder_free_message_info (folder, info);

    g_object_unref (folder);
}

/* only call if we have a tree model */
/* builds the tree structure */

static void build_subtree           (MessageList *message_list,
                         GNode *parent,
                         CamelFolderThreadNode *c,
                         gint *row);

static void build_subtree_diff      (MessageList *message_list,
                         GNode *parent,
                         GNode *node,
                         CamelFolderThreadNode *c,
                         gint *row);

static void
build_tree (MessageList *message_list,
            CamelFolderThread *thread,
            gboolean folder_changed)
{
    gint row = 0;
    ETableItem *table_item = e_tree_get_item (E_TREE (message_list));
    ETreeTableAdapter *adapter;
    gchar *saveuid = NULL;
    GPtrArray *selected;
#ifdef TIMEIT
    struct timeval start, end;
    gulong diff;

    printf ("Building tree\n");
    gettimeofday (&start, NULL);
#endif

#ifdef TIMEIT
    gettimeofday (&end, NULL);
    diff = end.tv_sec * 1000 + end.tv_usec / 1000;
    diff -= start.tv_sec * 1000 + start.tv_usec / 1000;
    printf ("Loading tree state took %ld.%03ld seconds\n", diff / 1000, diff % 1000);
#endif

    adapter = e_tree_get_table_adapter (E_TREE (message_list));

    if (message_list->priv->tree_model_root == NULL) {
        message_list_tree_model_insert (message_list, NULL, 0, NULL);
        g_warn_if_fail (message_list->priv->tree_model_root != NULL);
    }

    if (message_list->cursor_uid != NULL)
        saveuid = find_next_selectable (message_list);

    selected = message_list_get_selected (message_list);

    message_list_tree_model_freeze (message_list);

    clear_tree (message_list, FALSE);

    build_subtree (
        message_list,
        message_list->priv->tree_model_root,
        thread->tree, &row);

    /* Show the cursor unless we're responding to a
     * "folder-changed" signal from our CamelFolder. */
    if (folder_changed && table_item != NULL)
        table_item->queue_show_cursor = FALSE;

    message_list_tree_model_thaw (message_list);

    /* it's required to thaw & freeze, to propagate changes */
    message_list_tree_model_freeze (message_list);

    message_list_set_selected (message_list, selected);

    g_ptr_array_unref (selected);

    /* Show the cursor unless we're responding to a
     * "folder-changed" signal from our CamelFolder. */
    if (folder_changed && table_item != NULL)
        table_item->queue_show_cursor = FALSE;

    message_list_tree_model_thaw (message_list);

    if (!saveuid && message_list->cursor_uid && g_hash_table_lookup (message_list->uid_nodemap, message_list->cursor_uid)) {
        /* this makes sure a visible node is selected, like when
         * collapsing all nodes and a children had been selected
        */
        saveuid = g_strdup (message_list->cursor_uid);
    }

    if (saveuid) {
        GNode *node;

        node = g_hash_table_lookup (
            message_list->uid_nodemap, saveuid);
        if (node == NULL) {
            g_free (message_list->cursor_uid);
            message_list->cursor_uid = NULL;
            g_signal_emit (
                message_list,
                signals[MESSAGE_SELECTED], 0, NULL);
        } else {
            GNode *parent = node;

            while ((parent = parent->parent) != NULL) {
                if (!e_tree_table_adapter_node_is_expanded (adapter, parent))
                    node = parent;
            }

            message_list_tree_model_freeze (message_list);

            e_tree_set_cursor (E_TREE (message_list), node);

            /* Show the cursor unless we're responding to a
             * "folder-changed" signal from our CamelFolder. */
            if (folder_changed && table_item != NULL)
                table_item->queue_show_cursor = FALSE;

            message_list_tree_model_thaw (message_list);
        }
        g_free (saveuid);
    } else if (message_list->cursor_uid && !g_hash_table_lookup (message_list->uid_nodemap, message_list->cursor_uid)) {
        g_free (message_list->cursor_uid);
        message_list->cursor_uid = NULL;
        g_signal_emit (
            message_list,
            signals[MESSAGE_SELECTED], 0, NULL);
    }

#ifdef TIMEIT
    gettimeofday (&end, NULL);
    diff = end.tv_sec * 1000 + end.tv_usec / 1000;
    diff -= start.tv_sec * 1000 + start.tv_usec / 1000;
    printf ("Building tree took %ld.%03ld seconds\n", diff / 1000, diff % 1000);
#endif
}

/* this is about 20% faster than build_subtree_diff,
 * entirely because e_tree_model_node_insert (xx, -1 xx)
 * is faster than inserting to the right row :( */
/* Otherwise, this code would probably go as it does the same thing essentially */
static void
build_subtree (MessageList *message_list,
               GNode *parent,
               CamelFolderThreadNode *c,
               gint *row)
{
    GNode *node;

    while (c) {
        /* phantom nodes no longer allowed */
        if (!c->message) {
            g_warning ("c->message shouldn't be NULL\n");
            c = c->next;
            continue;
        }

        node = ml_uid_nodemap_insert (
            message_list,
            (CamelMessageInfo *) c->message, parent, -1);

        if (c->child) {
            build_subtree (message_list, node, c->child, row);
        }
        c = c->next;
    }
}

/* compares a thread tree node with the etable tree node to see if they point to
 * the same object */
static gint
node_equal (ETreeModel *etm,
            GNode *ap,
            CamelFolderThreadNode *bp)
{
    if (bp->message && strcmp (camel_message_info_uid (ap->data), camel_message_info_uid (bp->message)) == 0)
        return 1;

    return 0;
}

/* adds a single node, retains save state, and handles adding children if required */
static void
add_node_diff (MessageList *message_list,
               GNode *parent,
               GNode *node,
               CamelFolderThreadNode *c,
               gint *row,
               gint myrow)
{
    CamelMessageInfo *info;
    GNode *new_node;

    g_return_if_fail (c->message != NULL);

    /* XXX Casting away constness. */
    info = (CamelMessageInfo *) c->message;

    /* we just update the hashtable key */
    ml_uid_nodemap_remove (message_list, info);
    new_node = ml_uid_nodemap_insert (message_list, info, parent, myrow);
    (*row)++;

    if (c->child) {
        build_subtree_diff (
            message_list, new_node, NULL, c->child, row);
    }
}

/* removes node, children recursively and all associated data */
static void
remove_node_diff (MessageList *message_list,
                  GNode *node,
                  gint depth)
{
    ETreePath cp, cn;
    CamelMessageInfo *info;

    t (printf ("Removing node: %s\n", (gchar *) node->data));

    /* we depth-first remove all node data's ... */
    cp = g_node_first_child (node);
    while (cp) {
        cn = g_node_next_sibling (cp);
        remove_node_diff (message_list, cp, depth + 1);
        cp = cn;
    }

    /* and the rowid entry - if and only if it is referencing this node */
    info = node->data;

    /* and only at the toplevel, remove the node (etree should optimise this remove somewhat) */
    if (depth == 0)
        message_list_tree_model_remove (message_list, node);

    g_return_if_fail (info);
    ml_uid_nodemap_remove (message_list, info);
}

/* applies a new tree structure to an existing tree, but only by changing things
 * that have changed */
static void
build_subtree_diff (MessageList *message_list,
                    GNode *parent,
                    GNode *node,
                    CamelFolderThreadNode *c,
                    gint *row)
{
    ETreeModel *tree_model;
    GNode *ap, *ai, *at, *tmp;
    CamelFolderThreadNode *bp, *bi, *bt;
    gint i, j, myrow = 0;

    tree_model = E_TREE_MODEL (message_list);

    ap = node;
    bp = c;

    while (ap || bp) {
        t (printf ("Processing row: %d (subtree row %d)\n", *row, myrow));
        if (ap == NULL) {
            t (printf ("out of old nodes\n"));
            /* ran out of old nodes - remaining nodes are added */
            add_node_diff (
                message_list, parent, ap, bp, row, myrow);
            myrow++;
            bp = bp->next;
        } else if (bp == NULL) {
            t (printf ("out of new nodes\n"));
            /* ran out of new nodes - remaining nodes are removed */
            tmp = g_node_next_sibling (ap);
            remove_node_diff (message_list, ap, 0);
            ap = tmp;
        } else if (node_equal (tree_model, ap, bp)) {
            *row = (*row)+1;
            myrow++;
            tmp = g_node_first_child (ap);
            /* make child lists match (if either has one) */
            if (bp->child || tmp) {
                build_subtree_diff (
                    message_list, ap, tmp, bp->child, row);
            }
            ap = g_node_next_sibling (ap);
            bp = bp->next;
        } else {
            t (printf ("searching for matches\n"));
            /* we have to scan each side for a match */
            bi = bp->next;
            ai = g_node_next_sibling (ap);
            for (i = 1; bi != NULL; i++,bi = bi->next) {
                if (node_equal (tree_model, ap, bi))
                    break;
            }
            for (j = 1; ai != NULL; j++,ai = g_node_next_sibling (ai)) {
                if (node_equal (tree_model, ai, bp))
                    break;
            }
            if (i < j) {
                /* smaller run of new nodes - must be nodes to add */
                if (bi) {
                    bt = bp;
                    while (bt != bi) {
                        t (printf ("adding new node 0\n"));
                        add_node_diff (
                            message_list, parent, NULL, bt, row, myrow);
                        myrow++;
                        bt = bt->next;
                    }
                    bp = bi;
                } else {
                    t (printf ("adding new node 1\n"));
                    /* no match in new nodes, add one, try next */
                    add_node_diff (
                        message_list, parent, NULL, bp, row, myrow);
                    myrow++;
                    bp = bp->next;
                }
            } else {
                /* bigger run of old nodes - must be nodes to remove */
                if (ai) {
                    at = ap;
                    while (at != NULL && at != ai) {
                        t (printf ("removing old node 0\n"));
                        tmp = g_node_next_sibling (at);
                        remove_node_diff (message_list, at, 0);
                        at = tmp;
                    }
                    ap = ai;
                } else {
                    t (printf ("adding new node 2\n"));
                    /* didn't find match in old nodes, must be new node? */
                    add_node_diff (
                        message_list, parent, NULL, bp, row, myrow);
                    myrow++;
                    bp = bp->next;
                }
            }
        }
    }
}

static void
build_flat (MessageList *message_list,
            GPtrArray *summary)
{
    gchar *saveuid = NULL;
    gint i;
    GPtrArray *selected;
#ifdef TIMEIT
    struct timeval start, end;
    gulong diff;

    printf ("Building flat\n");
    gettimeofday (&start, NULL);
#endif

    if (message_list->cursor_uid != NULL)
        saveuid = find_next_selectable (message_list);

    selected = message_list_get_selected (message_list);

    message_list_tree_model_freeze (message_list);

    clear_tree (message_list, FALSE);

    for (i = 0; i < summary->len; i++) {
        CamelMessageInfo *info = summary->pdata[i];

        ml_uid_nodemap_insert (message_list, info, NULL, -1);
    }

    message_list_tree_model_thaw (message_list);

    message_list_set_selected (message_list, selected);

    g_ptr_array_unref (selected);

    if (saveuid) {
        GNode *node;

        node = g_hash_table_lookup (
            message_list->uid_nodemap, saveuid);
        if (node == NULL) {
            g_free (message_list->cursor_uid);
            message_list->cursor_uid = NULL;
            g_signal_emit (
                message_list,
                signals[MESSAGE_SELECTED], 0, NULL);
        } else {
            e_tree_set_cursor (E_TREE (message_list), node);
        }
        g_free (saveuid);
    }

#ifdef TIMEIT
    gettimeofday (&end, NULL);
    diff = end.tv_sec * 1000 + end.tv_usec / 1000;
    diff -= start.tv_sec * 1000 + start.tv_usec / 1000;
    printf ("Building flat took %ld.%03ld seconds\n", diff / 1000, diff % 1000);
#endif

}

static void
message_list_change_first_visible_parent (MessageList *message_list,
                                          GNode *node)
{
    ETreeModel *tree_model;
    ETreeTableAdapter *adapter;
    GNode *first_visible = NULL;

    tree_model = E_TREE_MODEL (message_list);
    adapter = e_tree_get_table_adapter (E_TREE (message_list));

    while (node != NULL && (node = node->parent) != NULL) {
        if (!e_tree_table_adapter_node_is_expanded (adapter, node))
            first_visible = node;
    }

    if (first_visible != NULL) {
        e_tree_model_pre_change (tree_model);
        e_tree_model_node_data_changed (tree_model, first_visible);
    }
}

static CamelFolderChangeInfo *
mail_folder_hide_by_flag (CamelFolder *folder,
                          MessageList *message_list,
                          CamelFolderChangeInfo *changes,
                          gint flag)
{
    CamelFolderChangeInfo *newchanges;
    CamelMessageInfo *info;
    gint i;

    newchanges = camel_folder_change_info_new ();

    for (i = 0; i < changes->uid_changed->len; i++) {
        GNode *node;
        guint32 flags;

        node = g_hash_table_lookup (
            message_list->uid_nodemap,
            changes->uid_changed->pdata[i]);
        info = camel_folder_get_message_info (
            folder, changes->uid_changed->pdata[i]);
        if (info)
            flags = camel_message_info_flags (info);

        if (node != NULL && info != NULL && (flags & flag) != 0)
            camel_folder_change_info_remove_uid (
                newchanges, changes->uid_changed->pdata[i]);
        else if (node == NULL && info != NULL && (flags & flag) == 0)
            camel_folder_change_info_add_uid (
                newchanges, changes->uid_changed->pdata[i]);
        else
            camel_folder_change_info_change_uid (
                newchanges, changes->uid_changed->pdata[i]);
        if (info)
            camel_folder_free_message_info (folder, info);
    }

    if (newchanges->uid_added->len > 0 || newchanges->uid_removed->len > 0) {
        for (i = 0; i < changes->uid_added->len; i++)
            camel_folder_change_info_add_uid (
                newchanges, changes->uid_added->pdata[i]);
        for (i = 0; i < changes->uid_removed->len; i++)
            camel_folder_change_info_remove_uid (
                newchanges, changes->uid_removed->pdata[i]);
    } else {
        camel_folder_change_info_clear (newchanges);
        camel_folder_change_info_cat (newchanges, changes);
    }

    return newchanges;
}

static void
message_list_folder_changed (CamelFolder *folder,
                             CamelFolderChangeInfo *changes,
                             MessageList *message_list)
{
    CamelFolderChangeInfo *altered_changes = NULL;
    ETreeModel *tree_model;
    gboolean need_list_regen = TRUE;
    gboolean hide_junk;
    gboolean hide_deleted;
    gint i;

    if (message_list->priv->destroyed)
        return;

    tree_model = E_TREE_MODEL (message_list);

    hide_junk = message_list_get_hide_junk (message_list, folder);
    hide_deleted = message_list_get_hide_deleted (message_list, folder);

    d (printf ("folder changed event, changes = %p\n", changes));
    if (changes != NULL) {
        for (i = 0; i < changes->uid_removed->len; i++)
            g_hash_table_remove (
                message_list->normalised_hash,
                changes->uid_removed->pdata[i]);

        /* Check if the hidden state has changed.
         * If so, modify accordingly and regenerate. */
        if (hide_junk || hide_deleted)
            altered_changes = mail_folder_hide_by_flag (
                folder, message_list, changes,
                (hide_junk ? CAMEL_MESSAGE_JUNK : 0) |
                (hide_deleted ? CAMEL_MESSAGE_DELETED : 0));
        else {
            altered_changes = camel_folder_change_info_new ();
            camel_folder_change_info_cat (altered_changes, changes);
        }

        if (altered_changes->uid_added->len == 0 && altered_changes->uid_removed->len == 0 && altered_changes->uid_changed->len < 100) {
            for (i = 0; i < altered_changes->uid_changed->len; i++) {
                GNode *node;

                node = g_hash_table_lookup (
                    message_list->uid_nodemap,
                    altered_changes->uid_changed->pdata[i]);
                if (node) {
                    e_tree_model_pre_change (tree_model);
                    e_tree_model_node_data_changed (tree_model, node);

                    message_list_change_first_visible_parent (message_list, node);
                }
            }

            g_signal_emit (
                message_list,
                signals[MESSAGE_LIST_BUILT], 0);

            need_list_regen = FALSE;
        }
    }

    if (need_list_regen)
        mail_regen_list (message_list, message_list->search, TRUE);

    if (altered_changes != NULL)
        camel_folder_change_info_free (altered_changes);
}

CamelFolder *
message_list_ref_folder (MessageList *message_list)
{
    CamelFolder *folder = NULL;

    /* XXX Do we need a property lock to guard this? */

    g_return_val_if_fail (IS_MESSAGE_LIST (message_list), NULL);

    if (message_list->priv->folder != NULL)
        folder = g_object_ref (message_list->priv->folder);

    return folder;
}

/**
 * message_list_set_folder:
 * @message_list: Message List widget
 * @folder: folder backend to be set
 *
 * Sets @folder to be the backend folder for @message_list.
 **/
void
message_list_set_folder (MessageList *message_list,
                         CamelFolder *folder)
{
    /* XXX Do we need a property lock to guard this? */

    g_return_if_fail (IS_MESSAGE_LIST (message_list));

    if (folder == message_list->priv->folder)
        return;

    if (folder != NULL) {
        g_return_if_fail (CAMEL_IS_FOLDER (folder));
        g_object_ref (folder);
    }

    g_free (message_list->search);
    message_list->search = NULL;

    g_free (message_list->frozen_search);
    message_list->frozen_search = NULL;

    if (message_list->seen_id) {
        g_source_remove (message_list->seen_id);
        message_list->seen_id = 0;
    }

    /* reset the normalised sort performance hack */
    g_hash_table_remove_all (message_list->normalised_hash);

    mail_regen_cancel (message_list);

    if (message_list->priv->folder != NULL)
        save_tree_state (message_list, message_list->priv->folder);

    message_list_tree_model_freeze (message_list);
    clear_tree (message_list, TRUE);
    message_list_tree_model_thaw (message_list);

    /* remove the cursor activate idle handler */
    if (message_list->idle_id != 0) {
        g_source_remove (message_list->idle_id);
        message_list->idle_id = 0;
    }

    if (message_list->priv->folder != NULL) {
        g_signal_handler_disconnect (
            message_list->priv->folder,
            message_list->priv->folder_changed_handler_id);
        message_list->priv->folder_changed_handler_id = 0;

        if (message_list->uid_nodemap != NULL)
            g_hash_table_foreach (
                message_list->uid_nodemap,
                (GHFunc) clear_info, message_list);

        g_clear_object (&message_list->priv->folder);
    }

    if (message_list->thread_tree != NULL) {
        camel_folder_thread_messages_unref (message_list->thread_tree);
        message_list->thread_tree = NULL;
    }

    g_free (message_list->cursor_uid);
    message_list->cursor_uid = NULL;

    /* Always emit message-selected, event when an account node
     * (folder == NULL) is selected, so that views know what happened and
     * can stop all running operations etc. */
    g_signal_emit (message_list, signals[MESSAGE_SELECTED], 0, NULL);

    if (folder != NULL) {
        CamelStore *store;
        gboolean non_trash_folder;
        gint strikeout_col;
        ECell *cell;
        gulong handler_id;

        message_list->priv->folder = folder;
        message_list->just_set_folder = TRUE;

        store = camel_folder_get_parent_store (folder);

        non_trash_folder =
            ((store->flags & CAMEL_STORE_VTRASH) == 0) ||
            ((folder->folder_flags & CAMEL_FOLDER_IS_TRASH) == 0);

        /* Setup the strikeout effect for non-trash folders */
        strikeout_col = non_trash_folder ? COL_DELETED : -1;

        cell = e_table_extras_get_cell (message_list->extras, "render_date");
        g_object_set (cell, "strikeout_column", strikeout_col, NULL);

        cell = e_table_extras_get_cell (message_list->extras, "render_text");
        g_object_set (cell, "strikeout_column", strikeout_col, NULL);

        cell = e_table_extras_get_cell (message_list->extras, "render_size");
        g_object_set (cell, "strikeout_column", strikeout_col, NULL);

        cell = e_table_extras_get_cell (message_list->extras, "render_composite_from");
        composite_cell_set_strike_col (cell, strikeout_col);

        cell = e_table_extras_get_cell (message_list->extras, "render_composite_to");
        composite_cell_set_strike_col (cell, strikeout_col);

        /* Build the etree suitable for this folder */
        message_list_setup_etree (message_list);

        handler_id = g_signal_connect (
            folder, "changed",
            G_CALLBACK (message_list_folder_changed),
            message_list);
        message_list->priv->folder_changed_handler_id = handler_id;

        if (message_list->frozen == 0)
            mail_regen_list (message_list, message_list->search, FALSE);
    }
}

GtkTargetList *
message_list_get_copy_target_list (MessageList *message_list)
{
    g_return_val_if_fail (IS_MESSAGE_LIST (message_list), NULL);

    return message_list->priv->copy_target_list;
}

GtkTargetList *
message_list_get_paste_target_list (MessageList *message_list)
{
    g_return_val_if_fail (IS_MESSAGE_LIST (message_list), NULL);

    return message_list->priv->paste_target_list;
}

void
message_list_set_expanded_default (MessageList *message_list,
                                   gboolean expanded_default)
{
    g_return_if_fail (IS_MESSAGE_LIST (message_list));

    message_list->priv->expanded_default = expanded_default;
}

gboolean
message_list_get_group_by_threads (MessageList *message_list)
{
    g_return_val_if_fail (IS_MESSAGE_LIST (message_list), FALSE);

    return message_list->priv->group_by_threads;
}

void
message_list_set_group_by_threads (MessageList *message_list,
                                   gboolean group_by_threads)
{
    g_return_if_fail (IS_MESSAGE_LIST (message_list));

    if (group_by_threads == message_list->priv->group_by_threads)
        return;

    message_list->priv->group_by_threads = group_by_threads;

    g_object_notify (G_OBJECT (message_list), "group-by-threads");

    /* Changing this property triggers a message list regen. */
    if (message_list->frozen == 0)
        mail_regen_list (message_list, message_list->search, FALSE);
}

gboolean
message_list_get_show_deleted (MessageList *message_list)
{
    g_return_val_if_fail (IS_MESSAGE_LIST (message_list), FALSE);

    return message_list->priv->show_deleted;
}

void
message_list_set_show_deleted (MessageList *message_list,
                               gboolean show_deleted)
{
    g_return_if_fail (IS_MESSAGE_LIST (message_list));

    if (show_deleted == message_list->priv->show_deleted)
        return;

    message_list->priv->show_deleted = show_deleted;

    g_object_notify (G_OBJECT (message_list), "show-deleted");

    /* Changing this property triggers a message list regen. */
    if (message_list->frozen == 0)
        mail_regen_list (message_list, message_list->search, FALSE);
}

gboolean
message_list_get_thread_latest (MessageList *message_list)
{
    g_return_val_if_fail (IS_MESSAGE_LIST (message_list), FALSE);

    return message_list->priv->thread_latest;
}

void
message_list_set_thread_latest (MessageList *message_list,
                                gboolean thread_latest)
{
    g_return_if_fail (IS_MESSAGE_LIST (message_list));

    if (thread_latest == message_list->priv->thread_latest)
        return;

    message_list->priv->thread_latest = thread_latest;

    g_object_notify (G_OBJECT (message_list), "thread-latest");
}

gboolean
message_list_get_thread_subject (MessageList *message_list)
{
    g_return_val_if_fail (IS_MESSAGE_LIST (message_list), FALSE);

    return message_list->priv->thread_subject;
}

void
message_list_set_thread_subject (MessageList *message_list,
                                 gboolean thread_subject)
{
    g_return_if_fail (IS_MESSAGE_LIST (message_list));

    if (thread_subject == message_list->priv->thread_subject)
        return;

    message_list->priv->thread_subject = thread_subject;

    g_object_notify (G_OBJECT (message_list), "thread-subject");
}

static gboolean
on_cursor_activated_idle (gpointer data)
{
    MessageList *message_list = data;
    ESelectionModel *esm;
    gint selected;

    esm = e_tree_get_selection_model (E_TREE (message_list));
    selected = e_selection_model_selected_count (esm);

    if (selected == 1 && message_list->cursor_uid) {
        d (printf ("emitting cursor changed signal, for uid %s\n", message_list->cursor_uid));
        g_signal_emit (
            message_list,
            signals[MESSAGE_SELECTED], 0,
            message_list->cursor_uid);
    } else {
        g_signal_emit (
            message_list,
            signals[MESSAGE_SELECTED], 0,
            NULL);
    }

    message_list->idle_id = 0;
    return FALSE;
}

static void
on_cursor_activated_cmd (ETree *tree,
                         gint row,
                         GNode *node,
                         gpointer user_data)
{
    MessageList *message_list = MESSAGE_LIST (user_data);
    const gchar *new_uid;

    if (node == NULL)
        new_uid = NULL;
    else
        new_uid = get_message_uid (message_list, node);

    /* Do not check the cursor_uid and the new_uid values, because the
    * selected item (set in on_selection_changed_cmd) can be different
    * from the one with a cursor (when selecting with Ctrl, for example).
    * This has a little side-effect, when keeping list it that state,
    * then changing folders forth and back will select and move cursor
    * to that selected item. Does anybody consider it as a bug? */
    if ((message_list->cursor_uid == NULL && new_uid == NULL)
        || (message_list->last_sel_single && message_list->cursor_uid != NULL && new_uid != NULL))
        return;

    g_free (message_list->cursor_uid);
    message_list->cursor_uid = g_strdup (new_uid);

    if (!message_list->idle_id) {
        message_list->idle_id =
            g_idle_add_full (
                G_PRIORITY_LOW, on_cursor_activated_idle,
                message_list, NULL);
    }
}

static void
on_selection_changed_cmd (ETree *tree,
                          MessageList *message_list)
{
    GPtrArray *uids;
    const gchar *newuid;
    GNode *cursor;

    /* not sure if we could just ignore this for the cursor, i think sometimes you
     * only get a selection changed when you should also get a cursor activated? */
    uids = message_list_get_selected (message_list);

    if (uids->len == 1)
        newuid = g_ptr_array_index (uids, 0);
    else if ((cursor = e_tree_get_cursor (tree)))
        newuid = (gchar *) camel_message_info_uid (cursor->data);
    else
        newuid = NULL;

    /* If the selection isn't empty, then we ignore the no-uid check, since this event
     * is also used for other updating.  If it is empty, it might just be a setup event
     * from etree which we do need to ignore */
    if ((newuid == NULL && message_list->cursor_uid == NULL && uids->len == 0) ||
        (message_list->last_sel_single && uids->len == 1 && newuid != NULL && message_list->cursor_uid != NULL && !strcmp (message_list->cursor_uid, newuid))) {
        /* noop */
    } else {
        g_free (message_list->cursor_uid);
        message_list->cursor_uid = g_strdup (newuid);
        if (message_list->idle_id == 0)
            message_list->idle_id = g_idle_add_full (
                G_PRIORITY_LOW,
                on_cursor_activated_idle,
                message_list, NULL);
    }

    message_list->last_sel_single = uids->len == 1;

    g_ptr_array_unref (uids);
}

static gint
on_click (ETree *tree,
          gint row,
          GNode *node,
          gint col,
          GdkEvent *event,
          MessageList *list)
{
    CamelFolder *folder;
    CamelMessageInfo *info;
    gboolean folder_is_trash;
    const gchar *uid;
    gint flag = 0;
    guint32 flags;

    if (col == COL_MESSAGE_STATUS)
        flag = CAMEL_MESSAGE_SEEN;
    else if (col == COL_FLAGGED)
        flag = CAMEL_MESSAGE_FLAGGED;
    else if (col != COL_FOLLOWUP_FLAG_STATUS)
        return FALSE;

    if (!(info = get_message_info (list, node)))
        return FALSE;

    folder = message_list_ref_folder (list);
    g_return_val_if_fail (folder != NULL, FALSE);

    if (col == COL_FOLLOWUP_FLAG_STATUS) {
        const gchar *tag, *cmp;

        tag = camel_message_info_user_tag (info, "follow-up");
        cmp = camel_message_info_user_tag (info, "completed-on");
        if (tag && tag[0]) {
            if (cmp && cmp[0]) {
                camel_message_info_set_user_tag (info, "follow-up", NULL);
                camel_message_info_set_user_tag (info, "due-by", NULL);
                camel_message_info_set_user_tag (info, "completed-on", NULL);
            } else {
                gchar *text;

                text = camel_header_format_date (time (NULL), 0);
                camel_message_info_set_user_tag (info, "completed-on", text);
                g_free (text);
            }
        } else {
            /* default follow-up flag name to use when clicked in the message list column */
            camel_message_info_set_user_tag (info, "follow-up", _("Follow-up"));
            camel_message_info_set_user_tag (info, "completed-on", NULL);
        }

        return TRUE;
    }

    flags = camel_message_info_flags (info);

    folder_is_trash =
        ((folder->folder_flags & CAMEL_FOLDER_IS_TRASH) != 0);

    /* If a message was marked as deleted and the user flags it as
     * important or unread in a non-Trash folder, then undelete the
     * message.  We avoid automatically undeleting messages while
     * viewing a Trash folder because it would cause the message to
     * suddenly disappear from the message list, which is confusing
     * and alarming to the user. */
    if (!folder_is_trash && flags & CAMEL_MESSAGE_DELETED) {
        if (col == COL_FLAGGED && !(flags & CAMEL_MESSAGE_FLAGGED))
            flag |= CAMEL_MESSAGE_DELETED;

        if (col == COL_MESSAGE_STATUS && (flags & CAMEL_MESSAGE_SEEN))
            flag |= CAMEL_MESSAGE_DELETED;
    }

    uid = camel_message_info_uid (info);
    camel_folder_set_message_flags (folder, uid, flag, ~flags);

    /* Notify the folder tree model that the user has marked a message
     * as unread so it doesn't mistake the event as new mail arriving. */
    if (col == COL_MESSAGE_STATUS && (flags & CAMEL_MESSAGE_SEEN)) {
        EMFolderTreeModel *model;

        model = em_folder_tree_model_get_default ();
        em_folder_tree_model_user_marked_unread (model, folder, 1);
    }

    if (flag == CAMEL_MESSAGE_SEEN && list->seen_id) {
        g_source_remove (list->seen_id);
        list->seen_id = 0;
    }

    g_object_unref (folder);

    return TRUE;
}

struct _ml_selected_data {
    MessageList *message_list;
    GPtrArray *uids;
};

static void
ml_getselected_cb (GNode *node,
                   gpointer user_data)
{
    struct _ml_selected_data *data = user_data;
    const gchar *uid;

    if (G_NODE_IS_ROOT (node))
        return;

    uid = get_message_uid (data->message_list, node);
    g_return_if_fail (uid != NULL);
    g_ptr_array_add (data->uids, g_strdup (uid));
}

GPtrArray *
message_list_get_selected (MessageList *message_list)
{
    CamelFolder *folder;
    ESelectionModel *selection;

    struct _ml_selected_data data = {
        message_list,
        g_ptr_array_new ()
    };

    g_ptr_array_set_free_func (data.uids, (GDestroyNotify) g_free);

    selection = e_tree_get_selection_model (E_TREE (message_list));

    e_tree_selection_model_foreach (
        E_TREE_SELECTION_MODEL (selection),
        (ETreeForeachFunc) ml_getselected_cb, &data);

    folder = message_list_ref_folder (message_list);

    if (folder != NULL && data.uids->len > 0)
        camel_folder_sort_uids (folder, data.uids);

    g_clear_object (&folder);

    return data.uids;
}

void
message_list_set_selected (MessageList *message_list,
                           GPtrArray *uids)
{
    gint i;
    ETreeSelectionModel *etsm;
    GNode *node;
    GPtrArray *paths = g_ptr_array_new ();

    etsm = (ETreeSelectionModel *)
        e_tree_get_selection_model (E_TREE (message_list));
    for (i = 0; i < uids->len; i++) {
        node = g_hash_table_lookup (
            message_list->uid_nodemap, uids->pdata[i]);
        if (node != NULL)
            g_ptr_array_add (paths, node);
    }

    e_tree_selection_model_select_paths (etsm, paths);
    g_ptr_array_free (paths, TRUE);
}

struct ml_sort_uids_data {
    gchar *uid;
    gint row;
};

static gint
ml_sort_uids_cb (gconstpointer a,
                 gconstpointer b)
{
    struct ml_sort_uids_data * const *pdataA = a;
    struct ml_sort_uids_data * const *pdataB = b;

    return (* pdataA)->row - (* pdataB)->row;
}

void
message_list_sort_uids (MessageList *message_list,
                        GPtrArray *uids)
{
    struct ml_sort_uids_data *data;
    GPtrArray *array;
    GNode *node;
    ETreeTableAdapter *adapter;
    gint ii;

    g_return_if_fail (message_list != NULL);
    g_return_if_fail (IS_MESSAGE_LIST (message_list));
    g_return_if_fail (uids != NULL);

    if (uids->len <= 1)
        return;

    adapter = e_tree_get_table_adapter (E_TREE (message_list));

    array = g_ptr_array_new_full (uids->len, g_free);

    for (ii = 0; ii < uids->len; ii++) {
        data = g_new0 (struct ml_sort_uids_data, 1);
        data->uid = g_ptr_array_index (uids, ii);

        node = g_hash_table_lookup (message_list->uid_nodemap, data->uid);
        if (node != NULL)
            data->row = e_tree_table_adapter_row_of_node (adapter, node);
        else
            data->row = ii;

        g_ptr_array_add (array, data);
    }

    g_ptr_array_sort (array, ml_sort_uids_cb);

    for (ii = 0; ii < uids->len; ii++) {
        data = g_ptr_array_index (array, ii);

        uids->pdata[ii] = data->uid;
    }

    g_ptr_array_free (array, TRUE);
}

struct ml_count_data {
    MessageList *message_list;
    guint count;
};

static void
ml_getcount_cb (GNode *node,
                gpointer user_data)
{
    struct ml_count_data *data = user_data;

    if (!G_NODE_IS_ROOT (node))
        data->count++;
}

guint
message_list_count (MessageList *message_list)
{
    struct ml_count_data data = { message_list, 0 };

    g_return_val_if_fail (IS_MESSAGE_LIST (message_list), 0);

    e_tree_path_foreach (
        E_TREE (message_list),
        (ETreeForeachFunc) ml_getcount_cb, &data);

    return data.count;
}

static void
ml_getselcount_cb (gint model_row,
                   gpointer user_data)
{
    struct ml_count_data *data = user_data;

    data->count++;
}

guint
message_list_selected_count (MessageList *message_list)
{
    ESelectionModel *selection;
    struct ml_count_data data = { message_list, 0 };

    g_return_val_if_fail (IS_MESSAGE_LIST (message_list), 0);

    selection = e_tree_get_selection_model (E_TREE (message_list));
    e_selection_model_foreach (selection, ml_getselcount_cb, &data);

    return data.count;
}

void
message_list_freeze (MessageList *message_list)
{
    message_list->frozen++;
}

void
message_list_thaw (MessageList *message_list)
{
    g_return_if_fail (message_list->frozen != 0);

    message_list->frozen--;
    if (message_list->frozen == 0) {
        const gchar *search;

        if (message_list->frozen_search != NULL)
            search = message_list->frozen_search;
        else
            search = message_list->search;

        mail_regen_list (message_list, search, FALSE);

        g_free (message_list->frozen_search);
        message_list->frozen_search = NULL;
    }
}

/* set whether we are in threaded view or flat view */
void
message_list_set_threaded_expand_all (MessageList *message_list)
{
    g_return_if_fail (IS_MESSAGE_LIST (message_list));

    if (message_list_get_group_by_threads (message_list)) {
        message_list->expand_all = 1;

        if (message_list->frozen == 0)
            mail_regen_list (
                message_list, message_list->search, FALSE);
    }
}

void
message_list_set_threaded_collapse_all (MessageList *message_list)
{
    g_return_if_fail (IS_MESSAGE_LIST (message_list));

    if (message_list_get_group_by_threads (message_list)) {
        message_list->collapse_all = 1;

        if (message_list->frozen == 0)
            mail_regen_list (
                message_list, message_list->search, FALSE);
    }
}

void
message_list_set_search (MessageList *message_list,
                         const gchar *search)
{
    if (search == NULL || search[0] == '\0')
        if (message_list->search == NULL || message_list->search[0] == '\0')
            return;

    if (search != NULL && message_list->search != NULL && strcmp (search, message_list->search) == 0)
        return;

    if (message_list->thread_tree) {
        camel_folder_thread_messages_unref (message_list->thread_tree);
        message_list->thread_tree = NULL;
    }

    if (message_list->frozen == 0)
        mail_regen_list (message_list, search, FALSE);
    else {
        g_free (message_list->frozen_search);
        message_list->frozen_search = g_strdup (search);
    }
}

struct sort_column_data {
    ETableCol *col;
    gboolean ascending;
};

struct sort_message_info_data {
    CamelMessageInfo *mi;
    GPtrArray *values; /* read values so far, in order of sort_array_data::sort_columns */
};

struct sort_array_data {
    MessageList *message_list;
    CamelFolder *folder;
    GPtrArray *sort_columns; /* struct sort_column_data in order of sorting */
    GHashTable *message_infos; /* uid -> struct sort_message_info_data */
    gpointer cmp_cache;
    GCancellable *cancellable;
};

static gint
cmp_array_uids (gconstpointer a,
                gconstpointer b,
                gpointer user_data)
{
    const gchar *uid1 = *(const gchar **) a;
    const gchar *uid2 = *(const gchar **) b;
    struct sort_array_data *sort_data = user_data;
    gint i, res = 0;
    struct sort_message_info_data *md1, *md2;

    g_return_val_if_fail (sort_data != NULL, 0);

    md1 = g_hash_table_lookup (sort_data->message_infos, uid1);
    md2 = g_hash_table_lookup (sort_data->message_infos, uid2);

    g_return_val_if_fail (md1 != NULL, 0);
    g_return_val_if_fail (md1->mi != NULL, 0);
    g_return_val_if_fail (md2 != NULL, 0);
    g_return_val_if_fail (md2->mi != NULL, 0);

    if (g_cancellable_is_cancelled (sort_data->cancellable))
        return 0;

    for (i = 0;
         res == 0
         && i < sort_data->sort_columns->len
         && !g_cancellable_is_cancelled (sort_data->cancellable);
         i++) {
        gpointer v1, v2;
        struct sort_column_data *scol = g_ptr_array_index (sort_data->sort_columns, i);

        if (md1->values->len <= i) {
            v1 = ml_tree_value_at_ex (NULL, NULL, scol->col->compare_col, md1->mi, sort_data->message_list);
            g_ptr_array_add (md1->values, v1);
        } else {
            v1 = g_ptr_array_index (md1->values, i);
        }

        if (md2->values->len <= i) {
            v2 = ml_tree_value_at_ex (NULL, NULL, scol->col->compare_col, md2->mi, sort_data->message_list);
            g_ptr_array_add (md2->values, v2);
        } else {
            v2 = g_ptr_array_index (md2->values, i);
        }

        if (v1 != NULL && v2 != NULL) {
            res = (*scol->col->compare) (v1, v2, sort_data->cmp_cache);
        } else if (v1 != NULL || v2 != NULL) {
            res = v1 == NULL ? -1 : 1;
        }

        if (!scol->ascending)
            res = res * (-1);
    }

    if (res == 0)
        res = camel_folder_cmp_uids (sort_data->folder, uid1, uid2);

    return res;
}

static void
free_message_info_data (gpointer uid,
                        struct sort_message_info_data *data,
                        struct sort_array_data *sort_data)
{
    if (data->values) {
        /* values in this array are not newly allocated, even ml_tree_value_at_ex
         * returns gpointer, not a gconstpointer */
        g_ptr_array_free (data->values, TRUE);
    }

    camel_folder_free_message_info (sort_data->folder, data->mi);
    g_free (data);
}

static void
ml_sort_uids_by_tree (MessageList *message_list,
                      GPtrArray *uids,
                      GCancellable *cancellable)
{
    ETreeTableAdapter *adapter;
    ETableSortInfo *sort_info;
    ETableHeader *full_header;
    CamelFolder *folder;
    struct sort_array_data sort_data;
    guint i, len;

    if (g_cancellable_is_cancelled (cancellable))
        return;

    g_return_if_fail (uids != NULL);

    folder = message_list_ref_folder (message_list);
    g_return_if_fail (folder != NULL);

    adapter = e_tree_get_table_adapter (E_TREE (message_list));
    g_return_if_fail (adapter != NULL);

    sort_info = e_tree_table_adapter_get_sort_info (adapter);
    full_header = e_tree_table_adapter_get_header (adapter);

    if (!sort_info || uids->len == 0 || !full_header || e_table_sort_info_sorting_get_count (sort_info) == 0) {
        camel_folder_sort_uids (folder, uids);
        g_object_unref (folder);
        return;
    }

    len = e_table_sort_info_sorting_get_count (sort_info);

    sort_data.message_list = message_list;
    sort_data.folder = folder;
    sort_data.sort_columns = g_ptr_array_sized_new (len);
    sort_data.message_infos = g_hash_table_new (g_str_hash, g_str_equal);
    sort_data.cmp_cache = e_table_sorting_utils_create_cmp_cache ();
    sort_data.cancellable = cancellable;

    for (i = 0;
         i < len
         && !g_cancellable_is_cancelled (cancellable);
         i++) {
        ETableSortColumn scol;
        struct sort_column_data *data = g_new0 (struct sort_column_data, 1);

        scol = e_table_sort_info_sorting_get_nth (sort_info, i);

        data->ascending = scol.ascending;
        data->col = e_table_header_get_column_by_col_idx (full_header, scol.column);
        if (data->col == NULL)
            data->col = e_table_header_get_column (full_header, e_table_header_count (full_header) - 1);

        g_ptr_array_add (sort_data.sort_columns, data);
    }

    camel_folder_summary_prepare_fetch_all (folder->summary, NULL);

    for (i = 0;
         i < uids->len
         && !g_cancellable_is_cancelled (cancellable);
         i++) {
        gchar *uid;
        CamelMessageInfo *mi;
        struct sort_message_info_data *md;

        uid = g_ptr_array_index (uids, i);
        mi = camel_folder_get_message_info (folder, uid);
        if (mi == NULL) {
            g_warning (
                "%s: Cannot find uid '%s' in folder '%s'",
                G_STRFUNC, uid,
                camel_folder_get_full_name (folder));
            continue;
        }

        md = g_new0 (struct sort_message_info_data, 1);
        md->mi = mi;
        md->values = g_ptr_array_sized_new (len);

        g_hash_table_insert (sort_data.message_infos, uid, md);
    }

    if (!g_cancellable_is_cancelled (cancellable))
        g_qsort_with_data (
            uids->pdata,
            uids->len,
            sizeof (gpointer),
            cmp_array_uids,
            &sort_data);

    camel_folder_summary_unlock (folder->summary, CAMEL_FOLDER_SUMMARY_SUMMARY_LOCK);

    /* FIXME Teach the hash table to destroy its own data. */
    g_hash_table_foreach (
        sort_data.message_infos,
        (GHFunc) free_message_info_data,
        &sort_data);
    g_hash_table_destroy (sort_data.message_infos);

    g_ptr_array_foreach (sort_data.sort_columns, (GFunc) g_free, NULL);
    g_ptr_array_free (sort_data.sort_columns, TRUE);

    e_table_sorting_utils_free_cmp_cache (sort_data.cmp_cache);

    g_object_unref (folder);
}

static void
message_list_regen_tweak_search_results (MessageList *message_list,
                                         GPtrArray *search_results,
                                         CamelFolder *folder,
                                         gboolean folder_changed,
                                         gboolean show_deleted,
                                         gboolean show_junk)
{
    CamelMessageInfo *info;
    CamelMessageFlags flags;
    const gchar *uid;
    gboolean needs_tweaking;
    gboolean uid_is_deleted;
    gboolean uid_is_junk;
    gboolean add_uid;
    guint ii;

    /* If we're responding to a "folder-changed" signal, then the
     * displayed message may not be included in the search results.
     * Include the displayed message anyway so it doesn't suddenly
     * disappear while the user is reading it. */
    needs_tweaking =
        (folder_changed && message_list->cursor_uid != NULL);

    if (!needs_tweaking)
        return;

    uid = message_list->cursor_uid;

    /* Scan the search results for a particular UID.
     * If found then the results don't need tweaked. */
    for (ii = 0; ii < search_results->len; ii++) {
        if (g_str_equal (uid, search_results->pdata[ii]))
            return;
    }

    info = camel_folder_get_message_info (folder, uid);

    /* XXX Should we emit a runtime warning here? */
    if (info == NULL)
        return;

    flags = camel_message_info_flags (info);
    uid_is_deleted = ((flags & CAMEL_MESSAGE_DELETED) != 0);
    uid_is_junk = ((flags & CAMEL_MESSAGE_JUNK) != 0);

    if (!folder_store_supports_vjunk_folder (folder))
        uid_is_junk = FALSE;

    add_uid =
        (!uid_is_junk || show_junk) &&
        (!uid_is_deleted || show_deleted);

    if (add_uid)
        g_ptr_array_add (
            search_results,
            (gpointer) camel_pstring_strdup (uid));

    camel_folder_free_message_info (folder, info);
}

static void
message_list_regen_thread (GSimpleAsyncResult *simple,
                           GObject *source_object,
                           GCancellable *cancellable)
{
    MessageList *message_list;
    RegenData *regen_data;
    GPtrArray *uids, *searchuids = NULL;
    CamelMessageInfo *info;
    GNode *cursor;
    ETree *tree;
    GString *expr;
    gboolean hide_deleted;
    gboolean hide_junk;
    GError *local_error = NULL;

    message_list = MESSAGE_LIST (source_object);
    regen_data = g_simple_async_result_get_op_res_gpointer (simple);

    if (g_cancellable_is_cancelled (cancellable))
        return;

    hide_junk = message_list_get_hide_junk (
        message_list, regen_data->folder);
    hide_deleted = message_list_get_hide_deleted (
        message_list, regen_data->folder);

    tree = E_TREE (message_list);
    cursor = e_tree_get_cursor (tree);
    if (cursor != NULL)
        regen_data->last_row =
            e_tree_table_adapter_row_of_node (
            e_tree_get_table_adapter (tree), cursor);

    /* Construct the search expression. */

    expr = g_string_new ("");

    if (hide_deleted && hide_junk) {
        g_string_append_printf (
            expr, "(match-all (and %s %s))",
            EXCLUDE_DELETED_MESSAGES_EXPR,
            EXCLUDE_JUNK_MESSAGES_EXPR);
    } else if (hide_deleted) {
        g_string_append_printf (
            expr, "(match-all %s)",
            EXCLUDE_DELETED_MESSAGES_EXPR);
    } else if (hide_junk) {
        g_string_append_printf (
            expr, "(match-all %s)",
            EXCLUDE_JUNK_MESSAGES_EXPR);
    }

    if (regen_data->search != NULL) {
        if (expr->len == 0) {
            g_string_assign (expr, regen_data->search);
        } else {
            g_string_prepend (expr, "(and ");
            g_string_append_c (expr, ' ');
            g_string_append (expr, regen_data->search);
            g_string_append_c (expr, ')');
        }
    }

    /* Execute the search. */

    if (expr->len == 0) {
        uids = camel_folder_get_uids (regen_data->folder);
    } else {
        uids = camel_folder_search_by_expression (
            regen_data->folder, expr->str,
            cancellable, &local_error);

        /* XXX This indicates we need to use a different
         *     "free UID" function for some dumb reason. */
        searchuids = uids;

        if (uids != NULL)
            message_list_regen_tweak_search_results (
                message_list, uids,
                regen_data->folder,
                regen_data->folder_changed,
                !hide_deleted,
                !hide_junk);
    }

    g_string_free (expr, TRUE);

    /* Handle search error or cancellation. */

    if (local_error == NULL)
        g_cancellable_set_error_if_cancelled (
            cancellable, &local_error);

    if (local_error != NULL) {
        g_simple_async_result_take_error (simple, local_error);
        goto exit;
    }

    /* XXX This check might not be necessary.  A successfully completed
     *     search with no results should return an empty UID array, but
     *     still need to verify that. */
    if (uids == NULL)
        goto exit;

    /* update/build a new tree */
    if (regen_data->group_by_threads) {
        ml_sort_uids_by_tree (message_list, uids, cancellable);

        if (regen_data->tree != NULL)
            camel_folder_thread_messages_apply (
                regen_data->tree, uids);
        else
            regen_data->tree = camel_folder_thread_messages_new (
                regen_data->folder, uids,
                regen_data->thread_subject);
    } else {
        guint ii;

        camel_folder_sort_uids (regen_data->folder, uids);
        regen_data->summary = g_ptr_array_new ();

        camel_folder_summary_prepare_fetch_all (
            regen_data->folder->summary, NULL);

        for (ii = 0; ii < uids->len; ii++) {
            info = camel_folder_get_message_info (
                regen_data->folder, uids->pdata[ii]);
            if (info != NULL)
                g_ptr_array_add (regen_data->summary, info);
        }
    }

exit:
    if (searchuids != NULL)
        camel_folder_search_free (regen_data->folder, searchuids);
    else if (uids != NULL)
        camel_folder_free_uids (regen_data->folder, uids);
}

static void
message_list_regen_done_cb (GObject *source_object,
                            GAsyncResult *result,
                            gpointer user_data)
{
    MessageList *message_list;
    GSimpleAsyncResult *simple;
    RegenData *regen_data;
    EActivity *activity;
    ETree *tree;
    ETreeTableAdapter *adapter;
    gboolean searching;
    GError *local_error = NULL;

    message_list = MESSAGE_LIST (source_object);
    simple = G_SIMPLE_ASYNC_RESULT (result);
    regen_data = g_simple_async_result_get_op_res_gpointer (simple);

    /* Withdraw our RegenData from the private struct, if it hasn't
     * already been replaced.  We have exclusive access to it now. */
    g_mutex_lock (&message_list->priv->regen_lock);
    if (message_list->priv->regen_data == regen_data) {
        regen_data_unref (message_list->priv->regen_data);
        message_list->priv->regen_data = NULL;
    }
    g_mutex_unlock (&message_list->priv->regen_lock);

    activity = regen_data->activity;

    g_simple_async_result_propagate_error (simple, &local_error);

    if (e_activity_handle_cancellation (activity, local_error)) {
        g_error_free (local_error);
        return;

    /* FIXME This should be handed off to an EAlertSink. */
    } else if (local_error != NULL) {
        g_warning ("%s: %s", G_STRFUNC, local_error->message);
        g_error_free (local_error);
        return;
    }

    e_activity_set_state (activity, E_ACTIVITY_COMPLETED);

    tree = E_TREE (message_list);
    adapter = e_tree_get_table_adapter (tree);

    /* Show the cursor unless we're responding to a
     * "folder-changed" signal from our CamelFolder. */
    if (!regen_data->folder_changed)
        e_tree_show_cursor_after_reflow (tree);

    g_signal_handlers_block_by_func (
        adapter, ml_tree_sorting_changed, message_list);

    g_free (message_list->search);
    message_list->search = g_strdup (regen_data->search);

    searching =
        (message_list->search != NULL) &&
        (*message_list->search != '\0');

    if (regen_data->group_by_threads) {
        gboolean forcing_expand_state;

        forcing_expand_state =
            message_list->expand_all ||
            message_list->collapse_all;

        if (message_list->just_set_folder) {
            message_list->just_set_folder = FALSE;
            if (regen_data->expand_state != NULL) {
                /* Load state from disk rather than use
                 * the memory data when changing folders. */
                xmlFreeDoc (regen_data->expand_state);
                regen_data->expand_state = NULL;
            }
        }

        if (forcing_expand_state || searching) {
            gint state;

            if (message_list->expand_all || searching)
                state = 1;  /* force expand */
            else
                state = -1; /* force collapse */

            e_tree_table_adapter_force_expanded_state (
                adapter, state);
        }

        /* Show the cursor unless we're responding to a
         * "folder-changed" signal from our CamelFolder. */
        build_tree (
            message_list,
            regen_data->tree,
            regen_data->folder_changed);

        if (message_list->thread_tree != NULL)
            camel_folder_thread_messages_unref (
                message_list->thread_tree);
        message_list->thread_tree = regen_data->tree;
        regen_data->tree = NULL;

        if (forcing_expand_state || searching) {
            if (message_list->priv->folder != NULL &&
                tree != NULL && !searching)
                save_tree_state (
                    message_list,
                    regen_data->folder);
            /* Disable forced expand/collapse state. */
            e_tree_table_adapter_force_expanded_state (adapter, 0);
        } else {
            load_tree_state (
                message_list,
                regen_data->folder,
                regen_data->expand_state);
        }

        message_list->expand_all = 0;
        message_list->collapse_all = 0;
    } else {
        build_flat (
            message_list,
            regen_data->summary);
    }

    if (regen_data->select_all) {
        message_list_select_all (message_list);

    } else if (regen_data->select_uid != NULL) {
        message_list_select_uid (
            message_list,
            regen_data->select_uid,
            regen_data->select_use_fallback);

    } else if (message_list->cursor_uid == NULL && regen_data->last_row != -1) {
        gint row_count;

        row_count = e_table_model_row_count (E_TABLE_MODEL (adapter));

        if (regen_data->last_row >= row_count)
            regen_data->last_row = row_count;

        if (regen_data->last_row >= 0) {
            GNode *node;

            node = e_tree_table_adapter_node_at_row (
                adapter, regen_data->last_row);
            if (node != NULL)
                select_node (message_list, node);
        }
    }

    if (gtk_widget_get_visible (GTK_WIDGET (message_list))) {
        const gchar *info_message;
        gboolean have_search_expr;

        /* space is used to indicate no search too */
        have_search_expr =
            (message_list->search != NULL) &&
            (*message_list->search != '\0') &&
            (strcmp (message_list->search, " ") != 0);

        if (e_tree_row_count (E_TREE (tree)) > 0) {
            info_message = NULL;
        } else if (have_search_expr) {
            info_message =
                _("No message satisfies your search criteria. "
                "Change search criteria by selecting a new "
                "Show message filter from the drop down list "
                "above or by running a new search either by "
                "clearing it with Search->Clear menu item or "
                "by changing the query above.");
        } else {
            info_message =
                _("There are no messages in this folder.");
        }

        e_tree_set_info_message (tree, info_message);
    }

    g_signal_handlers_unblock_by_func (
        adapter, ml_tree_sorting_changed, message_list);

    g_signal_emit (
        message_list,
        signals[MESSAGE_LIST_BUILT], 0);

    message_list->priv->any_row_changed = FALSE;
}

static gboolean
message_list_regen_idle_cb (gpointer user_data)
{
    GSimpleAsyncResult *simple;
    RegenData *regen_data;
    GCancellable *cancellable;

    simple = G_SIMPLE_ASYNC_RESULT (user_data);
    regen_data = g_simple_async_result_get_op_res_gpointer (simple);
    cancellable = e_activity_get_cancellable (regen_data->activity);

    g_mutex_lock (&regen_data->message_list->priv->regen_lock);
    regen_data->message_list->priv->regen_idle_id = 0;
    g_mutex_unlock (&regen_data->message_list->priv->regen_lock);

    if (g_cancellable_is_cancelled (cancellable)) {
        g_simple_async_result_complete (simple);
    } else {
        g_simple_async_result_run_in_thread (
            simple,
            message_list_regen_thread,
            G_PRIORITY_DEFAULT,
            cancellable);
    }

    return FALSE;
}

static void
mail_regen_cancel (MessageList *message_list)
{
    RegenData *regen_data = NULL;

    g_mutex_lock (&message_list->priv->regen_lock);

    if (message_list->priv->regen_data != NULL)
        regen_data = regen_data_ref (message_list->priv->regen_data);

    if (message_list->priv->regen_idle_id > 0) {
        g_source_remove (message_list->priv->regen_idle_id);
        message_list->priv->regen_idle_id = 0;
    }

    g_mutex_unlock (&message_list->priv->regen_lock);

    /* Cancel outside the lock, since this will emit a signal. */
    if (regen_data != NULL) {
        e_activity_cancel (regen_data->activity);
        regen_data_unref (regen_data);
    }
}

static void
mail_regen_list (MessageList *message_list,
                 const gchar *search,
                 gboolean folder_changed)
{
    GSimpleAsyncResult *simple;
    GCancellable *cancellable;
    RegenData *new_regen_data;
    RegenData *old_regen_data;

    /* Report empty search as NULL, not as one/two-space string. */
    if (search && (strcmp (search, " ") == 0 || strcmp (search, "  ") == 0))
        search = NULL;

    /* Can't list messages in a folder until we have a folder. */
    if (message_list->priv->folder == NULL) {
        g_free (message_list->search);
        message_list->search = g_strdup (search);
        return;
    }

    g_mutex_lock (&message_list->priv->regen_lock);

    old_regen_data = message_list->priv->regen_data;

    /* If a regen is scheduled but not yet started, just
     * apply the argument values without cancelling it. */
    if (message_list->priv->regen_idle_id > 0) {
        g_return_if_fail (old_regen_data != NULL);

        if (g_strcmp0 (search, old_regen_data->search) != 0) {
            g_free (old_regen_data->search);
            old_regen_data->search = g_strdup (search);
        }

        old_regen_data->folder_changed = folder_changed;

        /* Avoid cancelling on the way out. */
        old_regen_data = NULL;

        goto exit;
    }

    cancellable = g_cancellable_new ();

    new_regen_data = regen_data_new (message_list, cancellable);
    new_regen_data->search = g_strdup (search);
    new_regen_data->folder_changed = folder_changed;

    /* We generate the message list content in a worker thread, and
     * then supply our own GAsyncReadyCallback to redraw the widget. */

    simple = g_simple_async_result_new (
        G_OBJECT (message_list),
        message_list_regen_done_cb,
        NULL, mail_regen_list);

    g_simple_async_result_set_check_cancellable (simple, cancellable);

    g_simple_async_result_set_op_res_gpointer (
        simple,
        regen_data_ref (new_regen_data),
        (GDestroyNotify) regen_data_unref);

    /* Set the RegenData immediately, but start the actual regen
     * operation from an idle callback.  That way the caller has
     * the remainder of this main loop iteration to make further
     * MessageList changes without triggering additional regens. */

    message_list->priv->regen_data = regen_data_ref (new_regen_data);

    message_list->priv->regen_idle_id =
        g_idle_add_full (
            G_PRIORITY_DEFAULT_IDLE,
            message_list_regen_idle_cb,
            g_object_ref (simple),
            (GDestroyNotify) g_object_unref);

    g_object_unref (simple);

    regen_data_unref (new_regen_data);

    g_object_unref (cancellable);

exit:
    g_mutex_unlock (&message_list->priv->regen_lock);

    /* Cancel outside the lock, since this will emit a signal. */
    if (old_regen_data != NULL) {
        e_activity_cancel (old_regen_data->activity);
        regen_data_unref (old_regen_data);
    }
}