path: root/e-util/e-event.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 <gtk/gtk.h>

#include "e-event.h"

#include <glib/gi18n.h>
#include <libedataserver/e-msgport.h>

#define d(x)

struct _EEventFactory {
    struct _EEventFactory *next, *prev;

    gchar *menuid;
    EEventFactoryFunc factory;
    gpointer factory_data;
};

struct _event_node {
    struct _event_node *next, *prev;

    GSList *events;
    gpointer data;
    EEventItemsFunc freefunc;
};

struct _event_info {
    struct _event_node *parent;
    EEventItem *item;
};

struct _EEventPrivate {
    EDList events;

    GSList *sorted;     /* sorted list of struct _event_info's */
};

static GObjectClass *ep_parent;

static void
ep_init(GObject *o)
{
    EEvent *emp = (EEvent *)o;
    struct _EEventPrivate *p;

    p = emp->priv = g_malloc0(sizeof(struct _EEventPrivate));

    e_dlist_init(&p->events);
}

static void
ep_finalise(GObject *o)
{
    EEvent *emp = (EEvent *)o;
    struct _EEventPrivate *p = emp->priv;
    struct _event_node *node;

    if (emp->target)
        e_event_target_free(emp, emp->target);

    g_free(emp->id);

    while ((node = (struct _event_node *)e_dlist_remhead(&p->events))) {
        if (node->freefunc)
            node->freefunc(emp, node->events, node->data);

        g_free(node);
    }

    g_slist_foreach(p->sorted, (GFunc)g_free, NULL);
    g_slist_free(p->sorted);

    g_free(p);

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

static void
ep_target_free(EEvent *ep, EEventTarget *t)
{
    g_free(t);
    g_object_unref(ep);
}

static void
ep_class_init(GObjectClass *klass)
{
    d(printf("EEvent class init %p '%s'\n", klass, g_type_name(((GObjectClass *)klass)->g_type_class.g_type)));

    klass->finalize = ep_finalise;
    ((EEventClass *)klass)->target_free = ep_target_free;
}

/**
 * e_event_get_type:
 *
 * Standard GObject type function.  Used to subclass EEvent.
 *
 * Return value: The EEvent type.
 **/
GType
e_event_get_type(void)
{
    static GType type = 0;

    if (type == 0) {
        static const GTypeInfo info = {
            sizeof(EEventClass),
            (GBaseInitFunc)NULL, NULL,
            (GClassInitFunc)ep_class_init, NULL, NULL,
            sizeof(EEvent), 0,
            (GInstanceInitFunc)ep_init
        };
        ep_parent = g_type_class_ref(G_TYPE_OBJECT);
        type = g_type_register_static(G_TYPE_OBJECT, "EEvent", &info, 0);
    }

    return type;
}

/**
 * e_event_construct:
 * @ep: An instantiated but uninitialised EEvent.
 * @id: Event manager id.
 *
 * Construct the base event instance with standard parameters.
 *
 * Return value: Returns @ep.
 **/
EEvent *e_event_construct(EEvent *ep, const gchar *id)
{
    ep->id = g_strdup(id);

    return ep;
}

/**
 * e_event_add_items:
 * @emp: An initialised EEvent structure.
 * @items: A list of EEventItems event listeners to register on this event manager.
 * @freefunc: A function called when the @items list is no longer needed.
 * @data: callback data for @freefunc and for item event handlers.
 *
 * Adds @items to the list of events listened to on the event manager @emp.
 *
 * Return value: An opaque key which can later be passed to remove_items.
 **/
gpointer
e_event_add_items(EEvent *emp, GSList *items, EEventItemsFunc freefunc, gpointer data)
{
    struct _event_node *node;

    node = g_malloc(sizeof(*node));
    node->events = items;
    node->freefunc = freefunc;
    node->data = data;
    e_dlist_addtail(&emp->priv->events, (EDListNode *)node);

    if (emp->priv->sorted) {
        g_slist_foreach(emp->priv->sorted, (GFunc)g_free, NULL);
        g_slist_free(emp->priv->sorted);
        emp->priv->sorted = NULL;
    }

    return (gpointer)node;
}

/**
 * e_event_remove_items:
 * @emp:
 * @handle:
 *
 * Remove items previously added.  They MUST have been previously
 * added, and may only be removed once.
 **/
void
e_event_remove_items(EEvent *emp, gpointer handle)
{
    struct _event_node *node = handle;

    e_dlist_remove((EDListNode *)node);
    if (node->freefunc)
        node->freefunc(emp, node->events, node->data);
    g_free(node);

    if (emp->priv->sorted) {
        g_slist_foreach(emp->priv->sorted, (GFunc)g_free, NULL);
        g_slist_free(emp->priv->sorted);
        emp->priv->sorted = NULL;
    }
}

static gint
ee_cmp(gconstpointer ap, gconstpointer bp)
{
    gint a = ((struct _event_info **)ap)[0]->item->priority;
    gint b = ((struct _event_info **)bp)[0]->item->priority;

    if (a < b)
        return 1;
    else if (a > b)
        return -1;
    else
        return 0;
}

/**
 * e_event_emit:
 * @ee: An initialised EEvent, potentially with registered event listeners.
 * @id: Event name.  This will be compared against EEventItem.id.
 * @target: The target describing the event context.  This will be implementation defined.
 *
 * Emit an event.  @target will automatically be freed once its
 * emission is complete.
 **/
void
e_event_emit(EEvent *emp, const gchar *id, EEventTarget *target)
{
    struct _EEventPrivate *p = emp->priv;
    GSList *events;

    d(printf("emit event %s\n", id));

    if (emp->target != NULL) {
        g_warning ("Event already in progress.\n");
        return;
    }

    emp->target = target;
    events = p->sorted;
    if (events == NULL) {
        struct _event_node *node = (struct _event_node *)p->events.head;

        for (;node->next;node=node->next) {
            GSList *l = node->events;

            for (;l;l=g_slist_next(l)) {
                struct _event_info *info;

                info = g_malloc0(sizeof(*info));
                info->parent = node;
                info->item = l->data;
                events = g_slist_prepend(events, info);
            }
        }

        p->sorted = events = g_slist_sort(events, ee_cmp);
    }

    for (;events;events=g_slist_next(events)) {
        struct _event_info *info = events->data;
        EEventItem *event = info->item;

        d(printf("event '%s' mask %08x target %08x\n", event->id, event->enable, target->mask));

        if (event->enable & target->mask)
            continue;

        if (strcmp(event->id, id) == 0) {
            event->handle(emp, event, info->parent->data);

            if (event->type == E_EVENT_SINK)
                break;
        }
    }

    e_event_target_free(emp, target);
    emp->target = NULL;
}

/**
 * e_event_target_new:
 * @ep: An initialised EEvent instance.
 * @type: type, up to implementor
 * @size: The size of memory to allocate.  This must be >= sizeof(EEventTarget).
 *
 * Allocate a new event target suitable for this class.  It is up to
 * the implementation to define the available target types and their
 * structure.
 **/
gpointer e_event_target_new(EEvent *ep, gint type, gsize size)
{
    EEventTarget *t;

    if (size < sizeof(EEventTarget)) {
        g_warning ("Size is less than the size of EEventTarget\n");
        size = sizeof(EEventTarget);
    }

    t = g_malloc0(size);
    t->event = ep;
    g_object_ref(ep);
    t->type = type;

    return t;
}

/**
 * e_event_target_free:
 * @ep: An initialised EEvent instance on which this target was allocated.
 * @o: The target to free.
 *
 * Free a target.  This invokes the virtual free method on the EEventClass.
 **/
void
e_event_target_free(EEvent *ep, gpointer o)
{
    EEventTarget *t = o;

    ((EEventClass *)G_OBJECT_GET_CLASS(ep))->target_free(ep, t);
}

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

/* Event menu plugin handler */

/*
<e-plugin
  class="org.gnome.mail.plugin.event:1.0"
  id="org.gnome.mail.plugin.event.item:1.0"
  type="shlib"
  location="/opt/gnome2/lib/camel/1.0/libcamelimap.so"
  name="imap"
  description="IMAP4 and IMAP4v1 mail store">
  <hook class="org.gnome.mail.eventMenu:1.0"
        handler="HandleEvent">
  <menu id="any" target="select">
   <item
    type="item|toggle|radio|image|submenu|bar"
    active
    path="foo/bar"
    label="label"
    icon="foo"
    mask="select_one"
    activate="ep_view_emacs"/>
  </menu>
  </extension>

  <hook class="org.gnome.evolution.mail.events:1.0">
  <event id=".folder.changed"
  target=""
    priority="0"
    handle="gotevent"
    enable="new"
    />
  <event id=".message.read"
    priority="0"
    handle="gotevent"
    mask="new"
    />
  </hook>

*/

static gpointer emph_parent_class;
#define emph ((EEventHook *)eph)

/* must have 1:1 correspondence with e-event types in order */
static const EPluginHookTargetKey emph_item_types[] = {
    { "pass", E_EVENT_PASS },
    { "sink", E_EVENT_SINK },
    { NULL }
};

static void
emph_event_handle(EEvent *ee, EEventItem *item, gpointer data)
{
    struct _EEventHook *hook = data;

    /* FIXME: we could/should just remove the items we added to the event handler */
    if (!hook->hook.plugin->enabled)
        return;

    e_plugin_invoke(hook->hook.plugin, (gchar *)item->user_data, ee->target);
}

static void
emph_free_item(struct _EEventItem *item)
{
    g_free((gchar *)item->id);
    g_free(item->user_data);
    g_free(item);
}

static void
emph_free_items(EEvent *ee, GSList *items, gpointer data)
{
    /*EPluginHook *eph = data;*/

    g_slist_foreach(items, (GFunc)emph_free_item, NULL);
    g_slist_free(items);
}

static struct _EEventItem *
emph_construct_item(EPluginHook *eph, xmlNodePtr root, EEventHookClass *klass)
{
    struct _EEventItem *item;
    EEventHookTargetMap *map;
    gchar *tmp;

    item = g_malloc0(sizeof(*item));

    tmp = (gchar *)xmlGetProp(root, (const guchar *)"target");
    if (tmp == NULL)
        goto error;
    map = g_hash_table_lookup(klass->target_map, tmp);
    xmlFree(tmp);
    if (map == NULL)
        goto error;
    item->target_type = map->id;
    item->type = e_plugin_hook_id(root, emph_item_types, "type");
    if (item->type == -1)
        item->type = E_EVENT_PASS;
    item->priority = e_plugin_xml_int(root, "priority", 0);
    item->id = e_plugin_xml_prop(root, "id");
    item->enable = e_plugin_hook_mask(root, map->mask_bits, "enable");
    item->user_data = e_plugin_xml_prop(root, "handle");

    if (item->user_data == NULL || item->id == NULL)
        goto error;

    item->handle = emph_event_handle;

    return item;
error:
    emph_free_item(item);
    return NULL;
}

static gint
emph_construct(EPluginHook *eph, EPlugin *ep, xmlNodePtr root)
{
    xmlNodePtr node;
    EEventHookClass *klass;
    GSList *items = NULL;

    g_return_val_if_fail(((EEventHookClass *)G_OBJECT_GET_CLASS(eph))->event != NULL, -1);

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

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

    klass = (EEventHookClass *)G_OBJECT_GET_CLASS(eph);

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

            item = emph_construct_item(eph, node, klass);
            if (item)
                items = g_slist_prepend(items, item);
        }
        node = node->next;
    }

    eph->plugin = ep;

    if (items)
        e_event_add_items(klass->event, items, emph_free_items, eph);

    return 0;
}

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

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

static void
emph_class_init(EPluginHookClass *klass)
{
    ((GObjectClass *)klass)->finalize = emph_finalise;
    klass->construct = emph_construct;

    /* this is actually an abstract implementation but list it anyway */
    klass->id = "org.gnome.evolution.event:1.0";

    d(printf("EEventHook: init class %p '%s'\n", klass, g_type_name(((GObjectClass *)klass)->g_type_class.g_type)));

    ((EEventHookClass *)klass)->target_map = g_hash_table_new(g_str_hash, g_str_equal);
}

/**
 * e_event_hook_get_type:
 *
 * Standard GObject function to get the EEvent object type.  Used to
 * subclass EEventHook.
 *
 * Return value: The type of the event hook class.
 **/
GType
e_event_hook_get_type(void)
{
    static GType type = 0;

    if (!type) {
        static const GTypeInfo info = {
            sizeof(EEventHookClass), NULL, NULL, (GClassInitFunc) emph_class_init, NULL, NULL,
            sizeof(EEventHook), 0, (GInstanceInitFunc) NULL,
        };

        emph_parent_class = g_type_class_ref(e_plugin_hook_get_type());
        type = g_type_register_static(e_plugin_hook_get_type(), "EEventHook", &info, 0);
    }

    return type;
}

/**
 * e_event_hook_class_add_target_map:
 * @klass: The derived EEventHook class.
 * @map: A map used to describe a single EEventTarget type for this
 * class.
 *
 * Add a target map to a concrete derived class of EEvent.  The target
 * map enumerates a single target type and th eenable mask bit names,
 * so that the type can be loaded automatically by the base EEvent class.
 **/
void e_event_hook_class_add_target_map(EEventHookClass *klass, const EEventHookTargetMap *map)
{
    g_hash_table_insert(klass->target_map, (gpointer)map->type, (gpointer)map);
}