path: root/mail/em-format-hook.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:
 *      Michael Zucchi <notzed@ximian.com>
 *
 * Copyright (C) 1999-2008 Novell, Inc. (www.novell.com)
 *
 */

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

#include <string.h>
#include <stdlib.h>

#include "em-format-hook.h"

#include <glib/gi18n.h>

/* class name -> klass map for EMFormat and subclasses */
static GHashTable *emfh_types;

/* ********************************************************************** */

/* Mail formatter handler plugin */

/*
  <hook class="org.gnome.evolution.mail.format:1.0">
  <group id="EMFormatHTML">
     <item flags="inline,inline_disposition"
           mime_type="text/vcard"
       format="format_vcard"/>
  </group>
  </hook>

*/

static gpointer emfh_parent_class;
#define emfh ((EMFormatHook *)eph)

#define d(x)

static const EPluginHookTargetKey emfh_flag_map[] = {
    { "inline", EM_FORMAT_HANDLER_INLINE },
    { "inline_disposition", EM_FORMAT_HANDLER_INLINE_DISPOSITION },
    { NULL }
};

static void
emfh_format_format (EMFormat *md,
                    CamelStream *stream,
                    CamelMimePart *part,
                    const EMFormatHandler *info,
                    GCancellable *cancellable,
                    gboolean is_fallback)
{
    struct _EMFormatHookItem *item = (EMFormatHookItem *) info;

    if (item->hook->hook.plugin->enabled) {
        EMFormatHookTarget target = {
            md, stream, part, item
        };

        e_plugin_invoke (item->hook->hook.plugin, item->format, &target);
    } else if (info->old) {
        info->old->handler (
            md, stream, part, info->old, cancellable, FALSE);
    }
}

static void
emfh_free_item (struct _EMFormatHookItem *item)
{
    /* FIXME: remove from formatter class */

    g_free (item->handler.mime_type);
    g_free (item->format);
    g_free (item);
}

static void
emfh_free_group (struct _EMFormatHookGroup *group)
{
    g_slist_foreach (group->items, (GFunc) emfh_free_item, NULL);
    g_slist_free (group->items);

    g_free (group->id);
    g_free (group);
}

static struct _EMFormatHookItem *
emfh_construct_item (EPluginHook *eph, EMFormatHookGroup *group, xmlNodePtr root)
{
    struct _EMFormatHookItem *item;

    d(printf("  loading group item\n"));
    item = g_malloc0 (sizeof (*item));

    item->handler.mime_type = e_plugin_xml_prop(root, "mime_type");
    item->handler.flags = e_plugin_hook_mask(root, emfh_flag_map, "flags");
    item->format = e_plugin_xml_prop(root, "format");

    item->handler.handler = emfh_format_format;
    item->hook = emfh;

    if (item->handler.mime_type == NULL || item->format == NULL)
        goto error;

    d(printf("   type='%s' format='%s'\n", item->handler.mime_type, item->format));

    return item;
error:
    d(printf("error!\n"));
    emfh_free_item (item);
    return NULL;
}

static struct _EMFormatHookGroup *
emfh_construct_group (EPluginHook *eph, xmlNodePtr root)
{
    struct _EMFormatHookGroup *group;
    xmlNodePtr node;

    d(printf(" loading group\n"));
    group = g_malloc0 (sizeof (*group));

    group->id = e_plugin_xml_prop(root, "id");
    if (group->id == NULL)
        goto error;

    node = root->children;
    while (node) {
        if (0 == strcmp((gchar *)node->name, "item")) {
            struct _EMFormatHookItem *item;

            item = emfh_construct_item (eph, group, node);
            if (item)
                group->items = g_slist_append (group->items, item);
        }
        node = node->next;
    }

    return group;
error:
    emfh_free_group (group);
    return NULL;
}

static gint
emfh_construct (EPluginHook *eph, EPlugin *ep, xmlNodePtr root)
{
    xmlNodePtr node;

    d(printf("loading format hook\n"));

    if (((EPluginHookClass *) emfh_parent_class)->construct (eph, ep, root) == -1)
        return -1;

    node = root->children;
    while (node) {
        if (strcmp((gchar *)node->name, "group") == 0) {
            struct _EMFormatHookGroup *group;

            group = emfh_construct_group (eph, node);
            if (group) {
                EMFormatClass *klass;

                if (emfh_types
                    && (klass = g_hash_table_lookup (emfh_types, group->id))) {
                    GSList *l = group->items;

                    for (;l;l=g_slist_next (l)) {
                        EMFormatHookItem *item = l->data;
                        /* TODO: only add handlers if enabled? */
                        /* Well, disabling is handled by the callback,
                         * if we leave as is, then we can enable the
                         * plugin after startup and it will start
                         * working automagically */
                        em_format_class_add_handler (klass, &item->handler);
                    }
                }
                /* We don't actually need to keep this
                 * around once its set on the class. */
                emfh->groups = g_slist_append (emfh->groups, group);
            }
        }
        node = node->next;
    }

    eph->plugin = ep;

    /* Load the plugin as it does a few thing in the formatter thread. */
    ((EPluginClass *) G_OBJECT_GET_CLASS (ep))->enable (ep, 1);
    return 0;
}

static void
emfh_enable (EPluginHook *eph, gint state)
{
    GSList *g, *l;
    EMFormatClass *klass;

    g = emfh->groups;
    if (emfh_types == NULL)
        return;

    for (;g;g=g_slist_next (g)) {
        struct _EMFormatHookGroup *group = g->data;

        klass = g_hash_table_lookup (emfh_types, group->id);
        for (l=group->items;l;l=g_slist_next (l)) {
            EMFormatHookItem *item = l->data;

            if (state)
                em_format_class_add_handler (klass, &item->handler);
            else
                em_format_class_remove_handler (klass, &item->handler);
        }
    }
}

static void
emfh_finalise (GObject *o)
{
    EPluginHook *eph = (EPluginHook *) o;

    g_slist_foreach (emfh->groups, (GFunc) emfh_free_group, NULL);
    g_slist_free (emfh->groups);

    ((GObjectClass *) emfh_parent_class)->finalize (o);
}

static void
emfh_class_init (EPluginHookClass *klass)
{
    ((GObjectClass *) klass)->finalize = emfh_finalise;
    klass->construct = emfh_construct;
    klass->enable = emfh_enable;
    klass->id = "org.gnome.evolution.mail.format:1.0";
}

GType
em_format_hook_get_type (void)
{
    static GType type = 0;

    if (!type) {
        static const GTypeInfo info = {
            sizeof (EMFormatHookClass),
            (GBaseInitFunc) NULL,
            (GBaseFinalizeFunc) NULL,
            (GClassInitFunc) emfh_class_init,
            (GClassFinalizeFunc) NULL,
            NULL,  /* class_data */
            sizeof (EMFormatHook),
            0,     /* n_preallocs */
            (GInstanceInitFunc) NULL,
            NULL   /* value_table */
        };

        emfh_parent_class = g_type_class_ref (E_TYPE_PLUGIN_HOOK);
        type = g_type_register_static (
            E_TYPE_PLUGIN_HOOK, "EMFormatHook", &info, 0);
    }

    return type;
}

void
em_format_hook_register_type (GType type)
{
    EMFormatClass *klass;

    if (emfh_types == NULL)
        emfh_types = g_hash_table_new (g_str_hash, g_str_equal);

    d(printf("registering formatter type '%s'\n", g_type_name(type)));

    klass = g_type_class_ref (type);
    g_hash_table_insert (emfh_types, (gpointer) g_type_name (type), klass);
}