/*
 * 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_finalize (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_finalize;
	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);
}