path: root/mail/e-mail-request.c

/*
 * e-mail-request.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/>
 *
 */

#define LIBSOUP_USE_UNSTABLE_REQUEST_API

#include "e-mail-request.h"

#include <libsoup/soup.h>
#include <libsoup/soup-requester.h>
#include <libsoup/soup-request-http.h>

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

#include "em-format-html.h"

#include <e-util/e-icon-factory.h>
#include <e-util/e-util.h>

#define d(x)
#define dd(x)

#define E_MAIL_REQUEST_GET_PRIVATE(obj) \
    (G_TYPE_INSTANCE_GET_PRIVATE \
    ((obj), E_TYPE_MAIL_REQUEST, EMailRequestPrivate))

struct _EMailRequestPrivate {
    EMFormatHTML *efh;

    CamelStream *output_stream;
    EMFormatPURI *puri;
    gchar *mime_type;

    gint content_length;

    GHashTable *uri_query;

        gchar *ret_mime_type;
};

G_DEFINE_TYPE (EMailRequest, e_mail_request, SOUP_TYPE_REQUEST)

static void
handle_mail_request (GSimpleAsyncResult *res,
                     GObject *object,
                     GCancellable *cancellable)
{
    EMailRequest *request = E_MAIL_REQUEST (object);
    EMFormatHTML *efh = request->priv->efh;
    EMFormat *emf = EM_FORMAT (efh);
    GInputStream *stream;
    GByteArray *ba;
    gchar *part_id;
    EMFormatWriterInfo info = {0};
    gchar *val;

    if (g_cancellable_is_cancelled (cancellable))
        return;

    if (request->priv->output_stream != NULL) {
        g_object_unref (request->priv->output_stream);
    }

    request->priv->output_stream = camel_stream_mem_new ();

    val = g_hash_table_lookup (request->priv->uri_query, "headers_collapsed");
    if (val)
        info.headers_collapsed = atoi (val);

    val = g_hash_table_lookup (request->priv->uri_query, "headers_collapsable");
    if (val)
        info.headers_collapsable = atoi (val);

    val = g_hash_table_lookup (request->priv->uri_query, "mode");
    if (val)
        info.mode = atoi (val);

    part_id = g_hash_table_lookup (request->priv->uri_query, "part_id");
    if (part_id) {
        /* original part_id is owned by the GHashTable */
        part_id = soup_uri_decode (part_id);
        request->priv->puri = em_format_find_puri (emf, part_id);

        if (request->priv->puri) {
            em_format_puri_write (request->priv->puri,
                request->priv->output_stream, &info, NULL);
        } else {
            g_warning ("Failed to lookup requested part '%s' - this should not happen!", part_id);
        }

        g_free (part_id);
    } else {
        if (info.mode == 0)
            info.mode = EM_FORMAT_WRITE_MODE_NORMAL;

        em_format_write (emf, request->priv->output_stream, &info, NULL);
    }

    /* Convert the GString to GInputStream and send it back to WebKit */
    ba = camel_stream_mem_get_byte_array (CAMEL_STREAM_MEM (request->priv->output_stream));
    if (!ba->data) {
        gchar *data = g_strdup_printf(_("Failed to load part '%s'"), part_id);
        dd(printf("%s", data));
        g_byte_array_append (ba, (guchar *) data, strlen (data));
        g_free (data);
    } else {
        dd ({
            gchar *d = g_strndup ((gchar *) ba->data, ba->len);
            printf("%s", d);
            g_free (d);
        });
    }

    stream = g_memory_input_stream_new_from_data (
            (gchar *) ba->data, ba->len, NULL);
    g_simple_async_result_set_op_res_gpointer (res, stream, NULL);
}

static void
handle_file_request (GSimpleAsyncResult *res,
                     GObject *object,
                     GCancellable *cancellable)
{
    EMailRequest *request = E_MAIL_REQUEST (object);
    SoupURI *uri;
    GInputStream *stream;
    gchar *contents;
    gsize length;

    if (g_cancellable_is_cancelled (cancellable))
        return;

    uri = soup_request_get_uri (SOUP_REQUEST (request));

    if (g_file_get_contents (uri->path, &contents, &length, NULL)) {

        request->priv->mime_type = g_content_type_guess (uri->path, NULL, 0, NULL);
        request->priv->content_length = length;

        stream = g_memory_input_stream_new_from_data (
                contents, length, (GDestroyNotify) g_free);
        g_simple_async_result_set_op_res_gpointer (res, stream, NULL);
    }
}

struct http_request_async_data {
    GMainLoop *loop;
    GCancellable *cancellable;
    CamelDataCache *cache;
    gchar *cache_key;

    GInputStream *stream;
    CamelStream *cache_stream;
    gchar *content_type;
    goffset content_length;

    gchar *buff;
};

static void
http_request_write_to_cache (GInputStream *stream,
                             GAsyncResult *res,
                             struct http_request_async_data *data)
{
    GError *error;
    gssize len;

    error = NULL;
    len = g_input_stream_read_finish (stream, res, &error);

    /* Error while reading data */
    if (len == -1) {
        g_message ("Error while reading input stream: %s",
            error ? error->message : "Unknown error");
        g_clear_error (&error);

        g_main_loop_quit (data->loop);

        if (data->buff)
            g_free (data->buff);

        /* Don't keep broken data in cache */
        camel_data_cache_remove (data->cache, "http", data->cache_key, NULL);
        return;
    }

    /* EOF */
    if (len == 0) {
        camel_stream_close (data->cache_stream, data->cancellable, NULL);

        if (data->buff)
            g_free (data->buff);

        g_main_loop_quit (data->loop);
        return;
    }

    if (!data->cache_stream) {

        if (data->buff)
            g_free (data->buff);

        g_main_loop_quit (data->loop);
        return;
    }

    /* Write chunk to cache and read another block of data. */
    camel_stream_write (data->cache_stream, data->buff, len,
        data->cancellable, NULL);

    g_input_stream_read_async (stream, data->buff, 4096,
        G_PRIORITY_DEFAULT, data->cancellable,
        (GAsyncReadyCallback) http_request_write_to_cache, data);
}

static void
http_request_finished (SoupRequest *request,
                       GAsyncResult *res,
                       struct http_request_async_data *data)
{
    GError *error;
    SoupMessage *message;

    error = NULL;
    data->stream = soup_request_send_finish (request, res, &error);

    if (!data->stream) {
        g_warning("HTTP request failed: %s", error ? error->message: "Unknown error");
        g_clear_error (&error);
        g_main_loop_quit (data->loop);
        return;
    }

    message = soup_request_http_get_message (SOUP_REQUEST_HTTP (request));
    if (!SOUP_STATUS_IS_SUCCESSFUL (message->status_code)) {
        g_warning ("HTTP request failed: HTTP code %d", message->status_code);
        g_main_loop_quit (data->loop);
        g_object_unref (message);
        return;
    }

    g_object_unref (message);

    data->content_length = soup_request_get_content_length (request);
    data->content_type = g_strdup (soup_request_get_content_type (request));

    if (!data->cache_stream) {
        g_main_loop_quit (data->loop);
        return;
    }

    data->buff = g_malloc (4096);
    g_input_stream_read_async (data->stream, data->buff, 4096,
        G_PRIORITY_DEFAULT, data->cancellable,
        (GAsyncReadyCallback) http_request_write_to_cache, data);
}

static void
handle_http_request (GSimpleAsyncResult *res,
                     GObject *object,
                     GCancellable *cancellable)
{
    EMailRequest *request = E_MAIL_REQUEST (object);
    SoupURI *soup_uri;
    gchar *evo_uri, *uri;
    GInputStream *stream;
    gboolean force_load_images = FALSE;
    gchar *uri_md5;

    const gchar *user_cache_dir;
    CamelDataCache *cache;
    CamelStream *cache_stream;

    gssize len;
    gchar *buff;

    GHashTable *query;

    /* Remove the __evo-mail query */
    soup_uri = soup_request_get_uri (SOUP_REQUEST (request));
    query = soup_form_decode (soup_uri->query);
    g_hash_table_remove (query, "__evo-mail");

    /* Remove __evo-load-images if present (and in such case set
     * force_load_images to TRUE) */
    force_load_images = g_hash_table_remove (query, "__evo-load-images");

    soup_uri_set_query_from_form (soup_uri, query);
    g_hash_table_unref (query);

    evo_uri = soup_uri_to_string (soup_uri, FALSE);

    /* Remove the "evo-" prefix from scheme */
    if (evo_uri && (strlen (evo_uri) > 5)) {
        uri = g_strdup (&evo_uri[4]);
        g_free (evo_uri);
    }

    g_return_if_fail (uri && *uri);

    /* Use MD5 hash of the URI as a filname of the resourec cache file.
     * We were previously using the URI as a filename but the URI is
     * sometimes too long for a filename. */
    uri_md5 = g_compute_checksum_for_string (G_CHECKSUM_MD5, uri, -1);

    /* Open Evolution's cache */
    user_cache_dir = e_get_user_cache_dir ();
    cache = camel_data_cache_new (user_cache_dir, NULL);
    if (cache) {
        camel_data_cache_set_expire_age (cache, 24 * 60 * 60);
        camel_data_cache_set_expire_access (cache, 2 * 60 * 60);
    }

    /* Found item in cache! */
    cache_stream = camel_data_cache_get (cache, "http", uri_md5, NULL);
    if (cache_stream) {

        stream = g_memory_input_stream_new ();

        request->priv->content_length = 0;

        buff = g_malloc (4096);
        while ((len = camel_stream_read (cache_stream, buff, 4096,
                cancellable, NULL)) > 0) {

            g_memory_input_stream_add_data (G_MEMORY_INPUT_STREAM (stream),
                buff, len, g_free);
            request->priv->content_length += len;

            buff = g_malloc (4096);
        }

        g_object_unref (cache_stream);

        /* When succesfully read some data from cache then
         * get mimetype and return the stream to WebKit.
         * Otherwise try to fetch the resource again from the network. */
        if ((len != -1) && (request->priv->content_length > 0)) {
            GFile *file;
            GFileInfo *info;
            gchar *path;

            path = camel_data_cache_get_filename (cache, "http", uri_md5, NULL);
            file = g_file_new_for_path (path);
            info = g_file_query_info (file, G_FILE_ATTRIBUTE_STANDARD_CONTENT_TYPE,
                    0, cancellable, NULL);

            request->priv->mime_type = g_strdup (
                g_file_info_get_content_type (info));

            d(printf ("'%s' found in cache (%d bytes, %s)\n",
                uri, request->priv->content_length,
                request->priv->mime_type));

            g_object_unref (info);
            g_object_unref (file);
            g_free (path);

            /* Set result and quit the thread */
            g_simple_async_result_set_op_res_gpointer (res, stream, NULL);

            goto cleanup;
        } else {
            d(printf("Failed to load '%s' from cache.\n", uri));
        }
    }

    /* Item not found in cache, but image loading policy allows us to fetch
     * it from the interwebs */
    if (force_load_images || em_format_html_can_load_images (request->priv->efh)) {

        SoupRequester *requester;
        SoupRequest *http_request;
        SoupSession *session;
        GMainContext *context;
        GError *error;

        struct http_request_async_data data = { 0 };

        context = g_main_context_get_thread_default ();
        session = soup_session_async_new_with_options (
                    SOUP_SESSION_ASYNC_CONTEXT, context, NULL);

        requester = soup_requester_new ();
        soup_session_add_feature (session, SOUP_SESSION_FEATURE (requester));

        http_request = soup_requester_request (requester, uri, NULL);

        error = NULL;
        data.loop = g_main_loop_new (context, TRUE);
        data.cancellable = cancellable;
        data.cache = cache;
        data.cache_key = uri_md5;
        data.cache_stream = camel_data_cache_add (cache, "http", uri_md5, &error);

        if (!data.cache_stream) {
            g_warning ("Failed to create cache file for '%s': %s",
                uri, error ? error->message : "Unknown error");
            g_clear_error (&error);
        }

        /* Send the request and waint in mainloop until it's finished
         * and copied to cache */
        d(printf(" '%s' not in cache, sending HTTP request\n", uri));
        soup_request_send_async (http_request, cancellable,
            (GAsyncReadyCallback) http_request_finished, &data);

        g_main_loop_run (data.loop);
        d(printf (" '%s' fetched from internet and (hopefully) stored in"
              " cache\n", uri));

        g_main_loop_unref (data.loop);

        g_object_unref (session);

        g_object_unref (http_request);
        g_object_unref (requester);

        stream = data.stream;
        if (!stream)
            goto cleanup;

        request->priv->content_length = data.content_length;
        request->priv->mime_type = data.content_type;

        g_simple_async_result_set_op_res_gpointer (res, stream, NULL);

        goto cleanup;

    }

cleanup:
    g_free (uri);
    g_free (uri_md5);
}

static void
handle_stock_request (GSimpleAsyncResult *res,
                      GObject *object,
                      GCancellable *cancellable)
{
    EMailRequest *request;
    SoupURI *uri;
    GtkIconTheme *icon_theme;
    GtkIconInfo *icon_info;
    const gchar *file;
    gchar *a_size;
    gssize size;
    gchar *buffer;
    gsize buff_len;
    GtkStyleContext *context;
    GtkWidgetPath *path;
    GtkIconSet *set;

    request = E_MAIL_REQUEST (object);
    uri = soup_request_get_uri (SOUP_REQUEST (object));

    if (request->priv->uri_query) {
        a_size = g_hash_table_lookup (request->priv->uri_query, "size");
    } else {
        a_size = NULL;
    }

    if (!a_size) {
        size = GTK_ICON_SIZE_BUTTON;
    } else {
        size = atoi (a_size);
    }

    /* Try style context first */
    context = gtk_style_context_new ();
    path = gtk_widget_path_new ();
    gtk_widget_path_append_type (path, GTK_TYPE_WINDOW);
    gtk_widget_path_append_type (path, GTK_TYPE_BUTTON);
    gtk_style_context_set_path (context, path);

    set = gtk_style_context_lookup_icon_set (context, uri->host);
    if (!set) {
        /* Fallback to icon theme */
        icon_theme = gtk_icon_theme_get_default ();
        icon_info = gtk_icon_theme_lookup_icon (
                icon_theme, uri->host, size,
                GTK_ICON_LOOKUP_USE_BUILTIN);
        if (!icon_info) {
            gtk_widget_path_free (path);
            g_object_unref (context);
            return;
        }

        file = gtk_icon_info_get_filename (icon_info);
        buffer = NULL;
        if (file) {
            if (g_file_get_contents (file, &buffer, &buff_len, NULL)) {

                request->priv->mime_type =
                    g_content_type_guess (file, NULL, 0, NULL);
                request->priv->content_length = buff_len;
            }

        } else {
            GdkPixbuf *pixbuf;

            pixbuf = gtk_icon_info_get_builtin_pixbuf (icon_info);
            if (pixbuf) {
                gdk_pixbuf_save_to_buffer (
                    pixbuf, &buffer,
                    &buff_len, "png", NULL, NULL);

                request->priv->mime_type = g_strdup("image/png");
                request->priv->content_length = buff_len;

                g_object_unref (pixbuf);
            }
        }

        gtk_icon_info_free (icon_info);

    } else {
        GdkPixbuf *pixbuf;

        pixbuf = gtk_icon_set_render_icon_pixbuf (set, context, size);
                gdk_pixbuf_save_to_buffer (
                    pixbuf, &buffer,
                    &buff_len, "png", NULL, NULL);

        request->priv->mime_type = g_strdup("image/png");
        request->priv->content_length = buff_len;

        g_object_unref (pixbuf);
    }

    if (buffer) {
        GInputStream *stream;
        stream = g_memory_input_stream_new_from_data (
                buffer, buff_len, (GDestroyNotify) g_free);
        g_simple_async_result_set_op_res_gpointer (res, stream, NULL);
    }

    gtk_widget_path_free (path);
    g_object_unref (context);

}

static void
mail_request_finalize (GObject *object)
{
    EMailRequest *request = E_MAIL_REQUEST (object);

    if (request->priv->output_stream) {
        g_object_unref (request->priv->output_stream);
        request->priv->output_stream = NULL;
    }

    if (request->priv->mime_type) {
        g_free (request->priv->mime_type);
        request->priv->mime_type = NULL;
    }

    if (request->priv->uri_query) {
        g_hash_table_destroy (request->priv->uri_query);
        request->priv->uri_query = NULL;
    }

    if (request->priv->ret_mime_type) {
        g_free (request->priv->ret_mime_type);
        request->priv->ret_mime_type = NULL;
    }

    G_OBJECT_CLASS (e_mail_request_parent_class)->finalize (object);
}

static gboolean
mail_request_check_uri (SoupRequest *request,
                       SoupURI *uri,
                       GError **error)
{
    return ((strcmp (uri->scheme, "mail") == 0) ||
        (strcmp (uri->scheme, "evo-file") == 0) ||
        (strcmp (uri->scheme, "evo-http") == 0) ||
        (strcmp (uri->scheme, "evo-https") == 0) ||
        (strcmp (uri->scheme, "gtk-stock") == 0));
}

static void
mail_request_send_async (SoupRequest *request,
                         GCancellable *cancellable,
                         GAsyncReadyCallback callback,
                         gpointer user_data)
{
    SoupSession *session;
    EMailRequest *emr = E_MAIL_REQUEST (request);
    GSimpleAsyncResult *result;
    SoupURI *uri;
    GHashTable *formatters;

    session = soup_request_get_session (request);
    uri = soup_request_get_uri (request);

    d(printf("received request for %s\n", soup_uri_to_string (uri, FALSE)));

    /* WebKit won't allow us to load data through local file:// protocol
     * when using "remote" mail:// protocol, so we have evo-file://
     * which WebKit thinks it's remote, but in fact it behaves like
     * oridnary file:// */
    if (g_strcmp0 (uri->scheme, "evo-file") == 0) {

        result = g_simple_async_result_new (G_OBJECT (request), callback,
                user_data, mail_request_send_async);
        g_simple_async_result_run_in_thread (result, handle_file_request,
                G_PRIORITY_DEFAULT, cancellable);

        return;
    }

    if (uri->query) {
        emr->priv->uri_query = soup_form_decode (uri->query);
    } else {
        emr->priv->uri_query = NULL;
    }

    formatters = g_object_get_data (G_OBJECT (session), "formatters");
                    g_return_if_fail (formatters != NULL);

    /* Get HTML content of given PURI part */
    if (g_strcmp0 (uri->scheme, "mail") == 0) {
        gchar *uri_str;

        uri_str = g_strdup_printf (
            "%s://%s%s", uri->scheme, uri->host, uri->path);
        emr->priv->efh = g_hash_table_lookup (formatters, uri_str);
        g_free (uri_str);

        g_return_if_fail (emr->priv->efh);

        result = g_simple_async_result_new (G_OBJECT (request), callback,
                user_data, mail_request_send_async);
        g_simple_async_result_run_in_thread (result, handle_mail_request,
                G_PRIORITY_DEFAULT, cancellable);

        return;

    /* For http and https requests we have this evo-http(s) protocol.
     * We first try to lookup the data in local cache and when not found,
     * we send standard  http(s) request to fetch them. But only when image 
     * loading policy allows us. */
    } else if ((g_strcmp0 (uri->scheme, "evo-http") == 0) ||
           (g_strcmp0 (uri->scheme, "evo-https") == 0)) {

        gchar *mail_uri;
        const gchar *enc = g_hash_table_lookup (emr->priv->uri_query,
                    "__evo-mail");

        g_return_if_fail (enc && *enc);

        mail_uri = soup_uri_decode (enc);

        emr->priv->efh = g_hash_table_lookup (formatters, mail_uri);
        g_free (mail_uri);

        g_return_if_fail (emr->priv->efh);

        result = g_simple_async_result_new (G_OBJECT (request), callback,
                user_data, mail_request_send_async);
        g_simple_async_result_run_in_thread (result, handle_http_request,
                G_PRIORITY_DEFAULT, cancellable);

        return;

    } else if ((g_strcmp0 (uri->scheme, "gtk-stock") == 0)) {

        result = g_simple_async_result_new (G_OBJECT (request), callback,
                user_data, mail_request_send_async);
        g_simple_async_result_run_in_thread (result, handle_stock_request,
                G_PRIORITY_DEFAULT, cancellable);

        return;
    }
}

static GInputStream *
mail_request_send_finish (SoupRequest *request,
                          GAsyncResult *result,
                          GError **error)
{
    GInputStream *stream;

    stream = g_simple_async_result_get_op_res_gpointer (G_SIMPLE_ASYNC_RESULT (result));
    g_object_unref (result);

    /* Reset the stream before passing it back to webkit */
    if (stream && G_IS_SEEKABLE (stream))
        g_seekable_seek (G_SEEKABLE (stream), 0, G_SEEK_SET, NULL, NULL);
    else /* We must always return something */
        stream = g_memory_input_stream_new ();

    return stream;
}

static goffset
mail_request_get_content_length (SoupRequest *request)
{
    EMailRequest *emr = E_MAIL_REQUEST (request);
    GByteArray *ba;
    gint content_length = 0;

    if (emr->priv->content_length > 0)
        content_length = emr->priv->content_length;
    else if (emr->priv->output_stream) {
        ba = camel_stream_mem_get_byte_array (CAMEL_STREAM_MEM (emr->priv->output_stream));
        if (ba) {
            content_length = ba->len;
        }
    }

    d(printf("Content-Length: %d bytes\n", content_length));
    return content_length;
}

static const gchar *
mail_request_get_content_type (SoupRequest *request)
{
    EMailRequest *emr = E_MAIL_REQUEST (request);
    gchar *mime_type;

    if (emr->priv->mime_type) {
        mime_type = g_strdup (emr->priv->mime_type);
    } else if (!emr->priv->puri) {
        mime_type = g_strdup ("text/html");
    } else if (!emr->priv->puri->mime_type) {
        CamelContentType *ct = camel_mime_part_get_content_type (emr->priv->puri->part);
        mime_type = camel_content_type_simple (ct);
    } else {
        mime_type = g_strdup (emr->priv->puri->mime_type);
    }

    if (g_strcmp0 (mime_type, "text/html") == 0) {
        emr->priv->ret_mime_type = g_strconcat (mime_type, "; charset=\"UTF-8\"", NULL);
        g_free (mime_type);
    } else {
        emr->priv->ret_mime_type = mime_type;
    }

    d(printf("Content-Type: %s\n", emr->priv->ret_mime_type));

    return emr->priv->ret_mime_type;
}

static const char *data_schemes[] = { "mail", "evo-file", "evo-http", "evo-https", "gtk-stock", NULL };

static void
e_mail_request_class_init (EMailRequestClass *class)
{
    GObjectClass *object_class;
    SoupRequestClass *request_class;

    g_type_class_add_private (class, sizeof (EMailRequestPrivate));

    object_class = G_OBJECT_CLASS (class);
    object_class->finalize = mail_request_finalize;

    request_class = SOUP_REQUEST_CLASS (class);
    request_class->schemes = data_schemes;
    request_class->send_async = mail_request_send_async;
    request_class->send_finish = mail_request_send_finish;
    request_class->get_content_type = mail_request_get_content_type;
    request_class->get_content_length = mail_request_get_content_length;
    request_class->check_uri = mail_request_check_uri;
}

static void
e_mail_request_init (EMailRequest *request)
{
    request->priv = E_MAIL_REQUEST_GET_PRIVATE (request);
}