path: root/widgets/text/e-completion.c

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */

/* ECompletion - A base class for text completion.
 * Copyright (C) 2000, 2001 Ximian, Inc.
 *
 * Author: Miguel de Icaza <miguel@ximian.com>
 * Adapted by Jon Trowbridge <trow@ximian.com>
 *
 */

/*
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 *
 * 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
 * USA
 */


#include <config.h>
#include <string.h>
#include <stdio.h>
#include <gtk/gtk.h>
#include "e-completion.h"

enum {
    E_COMPLETION_REQUEST_COMPLETION,
    E_COMPLETION_BEGIN_COMPLETION,
    E_COMPLETION_COMPLETION,
    E_COMPLETION_RESTART_COMPLETION,
    E_COMPLETION_CANCEL_COMPLETION,
    E_COMPLETION_END_COMPLETION,
    E_COMPLETION_CLEAR_COMPLETION,
    E_COMPLETION_LOST_COMPLETION,
    E_COMPLETION_LAST_SIGNAL
};

static guint e_completion_signals[E_COMPLETION_LAST_SIGNAL] = { 0 };

struct _ECompletionPrivate {
    gboolean searching;
    gboolean done_search;
    gboolean refining;
    gchar *search_text;
    GPtrArray *matches;
    gint match_count;
    gint pos;
    gint limit;
    double min_score, max_score;
    gint refinement_count;
    GList *search_stack;
};

typedef struct {
    gchar *text;
    gint pos;
} ECompletionSearch;

static void e_completion_class_init (ECompletionClass *klass);
static void e_completion_init       (ECompletion *complete);
static void e_completion_destroy    (GtkObject *object);

static void     e_completion_add_match          (ECompletion *complete, ECompletionMatch *);
static void     e_completion_clear_search_stack (ECompletion *complete);
static void     e_completion_clear_matches      (ECompletion *complete);
static gboolean e_completion_sort               (ECompletion *complete);
static void     e_completion_restart            (ECompletion *complete);

static GtkObjectClass *parent_class;



GtkType
e_completion_get_type (void)
{
    static GtkType complete_type = 0;
  
    if (!complete_type) {
        GtkTypeInfo complete_info = {
            "ECompletion",
            sizeof (ECompletion),
            sizeof (ECompletionClass),
            (GtkClassInitFunc) e_completion_class_init,
            (GtkObjectInitFunc) e_completion_init,
            NULL, NULL, /* reserved */
            (GtkClassInitFunc) NULL
        };

        complete_type = gtk_type_unique (gtk_object_get_type (), &complete_info);
    }

    return complete_type;
}

static void
e_completion_class_init (ECompletionClass *klass)
{
    GtkObjectClass *object_class = (GtkObjectClass *) klass;

    parent_class = GTK_OBJECT_CLASS (gtk_type_class (gtk_object_get_type ()));

    e_completion_signals[E_COMPLETION_REQUEST_COMPLETION] =
        gtk_signal_new ("request_completion",
                GTK_RUN_LAST,
                object_class->type,
                GTK_SIGNAL_OFFSET (ECompletionClass, request_completion),
                gtk_marshal_NONE__POINTER_INT_INT,
                GTK_TYPE_NONE, 3,
                GTK_TYPE_POINTER, GTK_TYPE_INT, GTK_TYPE_INT);

    e_completion_signals[E_COMPLETION_BEGIN_COMPLETION] =
        gtk_signal_new ("begin_completion",
                GTK_RUN_LAST,
                object_class->type,
                GTK_SIGNAL_OFFSET (ECompletionClass, begin_completion),
                gtk_marshal_NONE__POINTER_INT_INT,
                GTK_TYPE_NONE, 3,
                GTK_TYPE_POINTER, GTK_TYPE_INT, GTK_TYPE_INT);

    e_completion_signals[E_COMPLETION_COMPLETION] =
        gtk_signal_new ("completion",
                GTK_RUN_LAST,
                object_class->type,
                GTK_SIGNAL_OFFSET (ECompletionClass, completion),
                gtk_marshal_NONE__POINTER,
                GTK_TYPE_NONE, 1,
                GTK_TYPE_POINTER);

    e_completion_signals[E_COMPLETION_RESTART_COMPLETION] =
        gtk_signal_new ("restart_completion",
                GTK_RUN_LAST,
                object_class->type,
                GTK_SIGNAL_OFFSET (ECompletionClass, restart_completion),
                gtk_marshal_NONE__NONE,
                GTK_TYPE_NONE, 0);

    e_completion_signals[E_COMPLETION_CANCEL_COMPLETION] =
        gtk_signal_new ("cancel_completion",
                GTK_RUN_LAST,
                object_class->type,
                GTK_SIGNAL_OFFSET (ECompletionClass, cancel_completion),
                gtk_marshal_NONE__NONE,
                GTK_TYPE_NONE, 0);

    e_completion_signals[E_COMPLETION_END_COMPLETION] =
        gtk_signal_new ("end_completion",
                GTK_RUN_LAST,
                object_class->type,
                GTK_SIGNAL_OFFSET (ECompletionClass, end_completion),
                gtk_marshal_NONE__NONE,
                GTK_TYPE_NONE, 0);

    e_completion_signals[E_COMPLETION_CLEAR_COMPLETION] = 
        gtk_signal_new ("clear_completion",
                GTK_RUN_LAST,
                object_class->type,
                GTK_SIGNAL_OFFSET (ECompletionClass, clear_completion),
                gtk_marshal_NONE__NONE,
                GTK_TYPE_NONE, 0);

    e_completion_signals[E_COMPLETION_LOST_COMPLETION] =
        gtk_signal_new ("lost_completion",
                GTK_RUN_LAST,
                object_class->type,
                GTK_SIGNAL_OFFSET (ECompletionClass, lost_completion),
                gtk_marshal_NONE__POINTER,
                GTK_TYPE_NONE, 1, GTK_TYPE_POINTER);

    gtk_object_class_add_signals (object_class, e_completion_signals, E_COMPLETION_LAST_SIGNAL);

    object_class->destroy = e_completion_destroy;
}

static void
e_completion_init (ECompletion *complete)
{
    complete->priv = g_new0 (struct _ECompletionPrivate, 1);
    complete->priv->matches = g_ptr_array_new ();
}

static void
e_completion_destroy (GtkObject *object)
{
    ECompletion *complete = E_COMPLETION (object);

    g_free (complete->priv->search_text);
    complete->priv->search_text = NULL;

    e_completion_clear_matches (complete);
    e_completion_clear_search_stack (complete);

    g_ptr_array_free (complete->priv->matches, TRUE);
    complete->priv->matches = NULL;

    g_free (complete->priv);
    complete->priv = NULL;

    if (parent_class->destroy)
        (parent_class->destroy) (object);
}

static void
e_completion_add_match (ECompletion *complete, ECompletionMatch *match)
{
    g_return_if_fail (complete && E_IS_COMPLETION (complete));
    g_return_if_fail (match != NULL);

    g_ptr_array_add (complete->priv->matches, match);

    if (complete->priv->matches->len == 1) {

        complete->priv->min_score = complete->priv->max_score = match->score;
        
    } else {

        complete->priv->min_score = MIN (complete->priv->min_score, match->score);
        complete->priv->max_score = MAX (complete->priv->max_score, match->score);

    }
}

static void
e_completion_clear_matches (ECompletion *complete)
{
    ECompletionMatch *match;
    GPtrArray *m;
    int i;

    g_return_if_fail (E_IS_COMPLETION (complete));

    m = complete->priv->matches;
    for (i = 0; i < m->len; i++) {
        match = g_ptr_array_index (m, i);
        e_completion_match_unref (match);
    }
    g_ptr_array_set_size (m, 0);

    complete->priv->min_score = 0;
    complete->priv->max_score = 0;
}

void
e_completion_clear (ECompletion *complete)
{
    g_return_if_fail (E_IS_COMPLETION (complete));

    /* FIXME: do we really want _clear and _clear_matches() ? */

    /* I think yes, because it is convenient to be able to clear our match cache
       without emitting a "clear_completion" signal. -JT */

    e_completion_clear_matches (complete);
    e_completion_clear_search_stack (complete);
    complete->priv->refinement_count = 0;
    complete->priv->match_count = 0;
    gtk_signal_emit (GTK_OBJECT (complete), e_completion_signals[E_COMPLETION_CLEAR_COMPLETION]);
}

static void
e_completion_push_search (ECompletion *complete, const gchar *text, gint pos)
{
    ECompletionSearch *search;

    g_return_if_fail (E_IS_COMPLETION (complete));

    search = g_new (ECompletionSearch, 1);
    search->text = complete->priv->search_text;
    search->pos  = complete->priv->pos;
    complete->priv->search_stack = g_list_prepend (complete->priv->search_stack, search);

    complete->priv->search_text = g_strdup (text);
    complete->priv->pos = pos;
}

static void
e_completion_pop_search (ECompletion *complete)
{
    ECompletionSearch *search;
    GList *old_link = complete->priv->search_stack;

    g_return_if_fail (E_IS_COMPLETION (complete));
    g_return_if_fail (complete->priv->search_stack != NULL);

    g_free (complete->priv->search_text);

    search = complete->priv->search_stack->data;
    complete->priv->search_text = search->text;
    complete->priv->pos = search->pos;

    g_free (search);
    complete->priv->search_stack = g_list_remove_link (complete->priv->search_stack,
                               complete->priv->search_stack);
    g_list_free_1 (old_link);
}

static void
e_completion_clear_search_stack (ECompletion *complete)
{
    GList *iter;
    
    g_return_if_fail (E_IS_COMPLETION (complete));

    for (iter = complete->priv->search_stack; iter != NULL; iter = g_list_next (iter)) {
        ECompletionSearch *search = iter->data;
        g_free (search->text);
        g_free (search);
    }
    g_list_free (complete->priv->search_stack);
    complete->priv->search_stack = NULL;
}

static void
e_completion_refine_search (ECompletion *comp, const gchar *text, gint pos, ECompletionRefineFn refine_fn)
{
    GPtrArray *m;
    gint i;
    
    comp->priv->refining = TRUE;

    e_completion_push_search (comp, text, pos);

    gtk_signal_emit (GTK_OBJECT (comp), e_completion_signals[E_COMPLETION_BEGIN_COMPLETION], text, pos, comp->priv->limit);

    comp->priv->match_count = 0;

    comp->priv->searching = TRUE;

    m = comp->priv->matches;
    for (i = 0; i < m->len; ++i) {
        ECompletionMatch *match = g_ptr_array_index (m, i);
        if (comp->priv->refinement_count == match->hit_count
            && refine_fn (comp, match, text, pos)) {
            ++match->hit_count;
            gtk_signal_emit (GTK_OBJECT (comp), e_completion_signals[E_COMPLETION_COMPLETION], match);
            ++comp->priv->match_count;
        }
    }

    ++comp->priv->refinement_count;

    gtk_signal_emit (GTK_OBJECT (comp), e_completion_signals[E_COMPLETION_END_COMPLETION]);

    comp->priv->searching = FALSE;
    comp->priv->refining  = FALSE;
}

static void
e_completion_unrefine_search (ECompletion *comp)
{
    GPtrArray *m;
    gint i;

    comp->priv->refining = TRUE;

    e_completion_pop_search (comp);

    gtk_signal_emit (GTK_OBJECT (comp), e_completion_signals[E_COMPLETION_BEGIN_COMPLETION], comp->priv->search_text, comp->priv->pos, comp->priv->limit);

    comp->priv->match_count = 0;
    --comp->priv->refinement_count;

    comp->priv->searching = TRUE;

    m = comp->priv->matches;
    for (i = 0; i < m->len; ++i) {
        ECompletionMatch *match = g_ptr_array_index (m, i);
        if (comp->priv->refinement_count <= match->hit_count) {
            match->hit_count = comp->priv->refinement_count;
            gtk_signal_emit (GTK_OBJECT (comp), e_completion_signals[E_COMPLETION_COMPLETION], match);
            ++comp->priv->match_count;
        }
    }

    gtk_signal_emit (GTK_OBJECT (comp), e_completion_signals[E_COMPLETION_END_COMPLETION]);

    comp->priv->searching = FALSE;
    comp->priv->refining  = FALSE;
}

void
e_completion_begin_search (ECompletion *complete, const gchar *text, gint pos, gint limit)
{
    ECompletionClass *klass;
    ECompletionRefineFn refine_fn;

    g_return_if_fail (complete != NULL);
    g_return_if_fail (E_IS_COMPLETION (complete));
    g_return_if_fail (text != NULL);

    klass = E_COMPLETION_CLASS (GTK_OBJECT (complete)->klass);

    if (!complete->priv->searching && complete->priv->done_search) {

        /* If the search we are requesting is the same as what we had before our last refinement,
           treat the request as an unrefine. */
        if (complete->priv->search_stack != NULL) {
            ECompletionSearch *search = complete->priv->search_stack->data;
            if ((klass->ignore_pos_on_auto_unrefine || search->pos == pos)
                && !strcmp (search->text, text)) {
                e_completion_unrefine_search (complete);
                return;
            }
        }

        if (klass->auto_refine 
            && (refine_fn = klass->auto_refine (complete,
                            complete->priv->search_text, complete->priv->pos,
                            text, pos))) {
            e_completion_refine_search (complete, text, pos, refine_fn);
            return;
        }

    }

    /* Stop any prior search. */
    if (complete->priv->searching)
        e_completion_cancel_search (complete);

    e_completion_clear_search_stack (complete);

    g_free (complete->priv->search_text);
    complete->priv->search_text = g_strdup (text);

    complete->priv->pos = pos;
    complete->priv->searching = TRUE;
    complete->priv->done_search = FALSE;

    e_completion_clear_matches (complete);

    complete->priv->limit = limit > 0 ? limit : G_MAXINT;
    complete->priv->refinement_count = 0;

    gtk_signal_emit (GTK_OBJECT (complete), e_completion_signals[E_COMPLETION_BEGIN_COMPLETION], text, pos, limit);
    gtk_signal_emit (GTK_OBJECT (complete), e_completion_signals[E_COMPLETION_REQUEST_COMPLETION], text, pos, limit);
}

void
e_completion_cancel_search (ECompletion *complete)
{
    g_return_if_fail (complete != NULL);
    g_return_if_fail (E_IS_COMPLETION (complete));

    /* If there is no search to cancel, just silently return. */
    if (!complete->priv->searching)
        return;

    gtk_signal_emit (GTK_OBJECT (complete), e_completion_signals[E_COMPLETION_CANCEL_COMPLETION]);

    complete->priv->searching = FALSE;
}

gboolean
e_completion_searching (ECompletion *complete)
{
    g_return_val_if_fail (complete != NULL, FALSE);
    g_return_val_if_fail (E_IS_COMPLETION (complete), FALSE);

    return complete->priv->searching;
}

gboolean
e_completion_refining (ECompletion *complete)
{
    g_return_val_if_fail (complete != NULL, FALSE);
    g_return_val_if_fail (E_IS_COMPLETION (complete), FALSE);

    return complete->priv->refining;
}

const gchar *
e_completion_search_text (ECompletion *complete)
{
    g_return_val_if_fail (complete != NULL, NULL);
    g_return_val_if_fail (E_IS_COMPLETION (complete), NULL);

    return complete->priv->search_text;
}

gint
e_completion_search_text_pos (ECompletion *complete)
{
    g_return_val_if_fail (complete != NULL, -1);
    g_return_val_if_fail (E_IS_COMPLETION (complete), -1);

    return complete->priv->pos;
}

gint
e_completion_match_count (ECompletion *complete)
{
    g_return_val_if_fail (complete != NULL, 0);
    g_return_val_if_fail (E_IS_COMPLETION (complete), 0);

    return complete->priv->refinement_count > 0 ? complete->priv->match_count : complete->priv->matches->len;
}

void
e_completion_foreach_match (ECompletion *complete, ECompletionMatchFn fn, gpointer closure)
{
    GPtrArray *m;
    int i;

    g_return_if_fail (complete != NULL);
    g_return_if_fail (E_IS_COMPLETION (complete));

    if (fn == NULL)
        return;

    m = complete->priv->matches;
    for (i = 0; i < m->len; i++) {
        ECompletionMatch *match = g_ptr_array_index (m, i);
        if (match->hit_count == complete->priv->refinement_count) {
            fn (match, closure);
        }
    }
}

ECompletion *
e_completion_new (void)
{
    return E_COMPLETION (gtk_type_new (e_completion_get_type ()));
}

static gboolean
e_completion_sort (ECompletion *complete)
{
    GPtrArray *m;
    int i;
    GList *sort_list = NULL, *j;
    gboolean diff;

    m = complete->priv->matches;

    for (i = 0; i < m->len; i++)
        sort_list = g_list_append (sort_list, 
                       g_ptr_array_index (m, i));
    
    sort_list = g_list_sort (sort_list, (GCompareFunc) e_completion_match_compare_alpha);

    diff = FALSE;

    for (i=0, j=sort_list; i < m->len; i++, j = g_list_next (j)) {
        if (g_ptr_array_index (m, i) == j->data)
            continue;

        diff = TRUE;
        g_ptr_array_index (m, i) = j->data;
    }

    g_list_free (sort_list);

    return diff;
}

/* Emit a restart signal and re-declare our matches, up to the limit. */
static void
e_completion_restart (ECompletion *complete)
{
    GPtrArray *m;
    gint i, count;

    gtk_signal_emit (GTK_OBJECT (complete), e_completion_signals[E_COMPLETION_RESTART_COMPLETION]);
    
    m = complete->priv->matches;
    for (i = count = 0; 
         i < m->len && count < complete->priv->limit; 
         i++, count++) {
        gtk_signal_emit (GTK_OBJECT (complete),
                 e_completion_signals[E_COMPLETION_COMPLETION], 
                 g_ptr_array_index (m, i));
    }
}

void
e_completion_found_match (ECompletion *complete, ECompletionMatch *match)
{
    g_return_if_fail (complete);
    g_return_if_fail (E_IS_COMPLETION (complete));
    g_return_if_fail (match != NULL);

    if (! complete->priv->searching) {
        g_warning ("e_completion_found_match(...,\"%s\",...) called outside of a search", match->match_text);
        return;
    }

    /* For now, do nothing when we hit the limit --- just don't
     * announce the incoming matches. */
    if (complete->priv->matches->len >= complete->priv->limit) {
        e_completion_match_unref (match);
        return;
    }

    e_completion_add_match (complete, match);

    gtk_signal_emit (GTK_OBJECT (complete), e_completion_signals[E_COMPLETION_COMPLETION], match);
}

/* to optimize this, make the match a hash table */
void
e_completion_lost_match (ECompletion *complete, ECompletionMatch *match)
{
    gboolean removed;

    g_return_if_fail (E_IS_COMPLETION (complete));
    g_return_if_fail (match != NULL);

    /* FIXME: remove fast */
    removed = g_ptr_array_remove (complete->priv->matches,
                      match);

    /* maybe just return here? */
    g_return_if_fail (removed);

    gtk_signal_emit (GTK_OBJECT (complete), e_completion_signals[E_COMPLETION_LOST_COMPLETION], match);

    e_completion_match_unref (match);
}

void
e_completion_end_search (ECompletion *complete)
{
    g_return_if_fail (complete != NULL);
    g_return_if_fail (E_IS_COMPLETION (complete));
    g_return_if_fail (complete->priv->searching);

    /* our table model should be sorted by a non-visible column of
     * doubles (the score) rather than whatever we are doing 
     */
    /* If sorting by score accomplishes anything, issue a restart right before we end. */
    if (e_completion_sort (complete))
        e_completion_restart (complete);

    gtk_signal_emit (GTK_OBJECT (complete), e_completion_signals[E_COMPLETION_END_COMPLETION]);

    complete->priv->searching = FALSE;
    complete->priv->done_search = TRUE;
}