/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
/*
 * Exports the BookViewListener interface.  Maintains a queue of messages
 * which come in on the interface.
 *
 * Author:
 *   Nat Friedman (nat@ximian.com)
 *
 * Copyright 2000, Ximian, Inc.
 */

#include <config.h>
#include <gtk/gtksignal.h>
#include "e-book-view-listener.h"
#include "e-book-view.h"
#include "e-card.h"

enum {
	RESPONSES_QUEUED,
	LAST_SIGNAL
};

static guint e_book_view_listener_signals [LAST_SIGNAL];

static BonoboObjectClass          *e_book_view_listener_parent_class;
POA_GNOME_Evolution_Addressbook_BookViewListener__vepv  e_book_view_listener_vepv;

struct _EBookViewListenerPrivate {
	GList   *response_queue;
	gint     timeout_id;

	guint timeout_lock : 1;
	guint stopped      : 1;
};

static gboolean
e_book_view_listener_check_queue (EBookViewListener *listener)
{
	if (listener->priv->timeout_lock)
		return TRUE;

	listener->priv->timeout_lock = TRUE;

	if (listener->priv->response_queue != NULL && !listener->priv->stopped) {
		gtk_signal_emit (GTK_OBJECT (listener), e_book_view_listener_signals [RESPONSES_QUEUED]);
	}

	if (listener->priv->response_queue == NULL || listener->priv->stopped) {
		listener->priv->timeout_id = 0;
		listener->priv->timeout_lock = FALSE;
		bonobo_object_unref (BONOBO_OBJECT (listener));
		return FALSE;
	}

	listener->priv->timeout_lock = FALSE;
	return TRUE;
}

static void
e_book_view_listener_queue_response (EBookViewListener         *listener,
				     EBookViewListenerResponse *response)
{
	if (response == NULL)
		return;

	if (listener->priv->stopped) {
		/* Free response and return */
		g_free (response->id);
		g_list_foreach (response->cards, (GFunc) gtk_object_unref, NULL);
		g_list_free (response->cards);
		g_free (response->message);
		g_free (response);
		return;
	}

	/* a slight optimization for huge ldap queries.  if there's an
	   existing Add response on the end of the queue, and we're an
	   Add response, we just glom the two lists of cards
	   together */
	if (response->op == CardAddedEvent) {
		GList *last = g_list_last (listener->priv->response_queue);
		EBookViewListenerResponse *last_resp = NULL;

		if (last) last_resp = last->data;

		if (last_resp && last_resp->op == CardAddedEvent ) {
			response->cards = g_list_concat (last_resp->cards, response->cards);
			g_free (response);
			/* there should already be a timeout since the
			   queue isn't empty, so we'll just return
			   here */
			return;
		}
		else
			listener->priv->response_queue = g_list_append (last, response);
	}
	else
		listener->priv->response_queue = g_list_append (listener->priv->response_queue, response);

	if (listener->priv->timeout_id == 0) {

		/* Here, 20 == an arbitrary small number */		
		listener->priv->timeout_id = g_timeout_add (20, (GSourceFunc) e_book_view_listener_check_queue, listener);

		/* Hold a reference to the listener on behalf of the timeout */
		bonobo_object_ref (BONOBO_OBJECT (listener));
	}
}

/* Add, Remove, Modify */
static void
e_book_view_listener_queue_empty_event (EBookViewListener          *listener,
					EBookViewListenerOperation  op)
{
	EBookViewListenerResponse *resp;

	if (listener->priv->stopped)
		return;

	resp = g_new0 (EBookViewListenerResponse, 1);

	resp->op        = op;
	resp->id        = NULL;
	resp->cards     = NULL;
	resp->message   = NULL;

	e_book_view_listener_queue_response (listener, resp);
}

/* Add, Remove, Modify */
static void
e_book_view_listener_queue_id_event (EBookViewListener          *listener,
				     EBookViewListenerOperation  op,
				     const char             *id)
{
	EBookViewListenerResponse *resp;

	if (listener->priv->stopped)
		return;

	resp = g_new0 (EBookViewListenerResponse, 1);

	resp->op        = op;
	resp->id        = g_strdup (id);
	resp->cards     = NULL;
	resp->message   = NULL;

	e_book_view_listener_queue_response (listener, resp);
}

/* Add, Remove, Modify */
static void
e_book_view_listener_queue_sequence_event (EBookViewListener          *listener,
					   EBookViewListenerOperation  op,
					   const GNOME_Evolution_Addressbook_VCardList  *cards)
{
	EBookViewListenerResponse *resp;
	int i;

	if (listener->priv->stopped)
		return;

	resp = g_new0 (EBookViewListenerResponse, 1);

	resp->op        = op;
	resp->id        = NULL;
	resp->cards     = NULL;
	resp->message   = NULL;
	
	for ( i = 0; i < cards->_length; i++ ) {
		resp->cards = g_list_append(resp->cards, e_card_new(cards->_buffer[i]));
	}

	e_book_view_listener_queue_response (listener, resp);
}

/* Status Message */
static void
e_book_view_listener_queue_message_event (EBookViewListener          *listener,
					  EBookViewListenerOperation  op,
					  const char                 *message)
{
	EBookViewListenerResponse *resp;

	if (listener->priv->stopped)
		return;

	resp = g_new0 (EBookViewListenerResponse, 1);

	resp->op        = op;
	resp->id        = NULL;
	resp->cards     = NULL;
	resp->message   = g_strdup(message);

	e_book_view_listener_queue_response (listener, resp);
}

static void
impl_BookViewListener_notify_card_added (PortableServer_Servant servant,
					 const GNOME_Evolution_Addressbook_VCardList *cards,
					 CORBA_Environment *ev)
{
	EBookViewListener *listener = E_BOOK_VIEW_LISTENER (bonobo_object_from_servant (servant));

	e_book_view_listener_queue_sequence_event (
		listener, CardAddedEvent, cards);
}

static void
impl_BookViewListener_notify_card_removed (PortableServer_Servant servant,
					   const GNOME_Evolution_Addressbook_CardId id,
					   CORBA_Environment *ev)
{
	EBookViewListener *listener = E_BOOK_VIEW_LISTENER (bonobo_object_from_servant (servant));

	e_book_view_listener_queue_id_event (
		listener, CardRemovedEvent, (const char *) id);
}

static void
impl_BookViewListener_notify_card_changed (PortableServer_Servant servant,
					   const GNOME_Evolution_Addressbook_VCardList *cards,
					   CORBA_Environment *ev)
{
	EBookViewListener *listener = E_BOOK_VIEW_LISTENER (bonobo_object_from_servant (servant));

	e_book_view_listener_queue_sequence_event (
		listener, CardModifiedEvent, cards);
}

static void
impl_BookViewListener_notify_sequence_complete (PortableServer_Servant servant,
						CORBA_Environment *ev)
{
	EBookViewListener *listener = E_BOOK_VIEW_LISTENER (bonobo_object_from_servant (servant));

	e_book_view_listener_queue_empty_event (listener, SequenceCompleteEvent);
}

static void
impl_BookViewListener_notify_status_message (PortableServer_Servant  servant,
					     const char             *message,
					     CORBA_Environment      *ev)
{
	EBookViewListener *listener = E_BOOK_VIEW_LISTENER (bonobo_object_from_servant (servant));

	e_book_view_listener_queue_message_event (listener, StatusMessageEvent, message);
}

/**
 * e_book_view_listener_check_pending:
 * @listener: the #EBookViewListener 
 *
 * Returns: the number of items on the response queue,
 * or -1 if the @listener is isn't an #EBookViewListener.
 */
int
e_book_view_listener_check_pending (EBookViewListener *listener)
{
	g_return_val_if_fail (listener != NULL,              -1);
	g_return_val_if_fail (E_IS_BOOK_VIEW_LISTENER (listener), -1);

	return g_list_length (listener->priv->response_queue);
}

/**
 * e_book_view_listener_pop_response:
 * @listener: the #EBookViewListener for which a request is to be popped
 *
 * Returns: an #EBookViewListenerResponse if there are responses on the
 * queue to be returned; %NULL if there aren't, or if the @listener
 * isn't an EBookViewListener.
 */
EBookViewListenerResponse *
e_book_view_listener_pop_response (EBookViewListener *listener)
{
	EBookViewListenerResponse *resp;
	GList                 *popped;

	g_return_val_if_fail (listener != NULL,              NULL);
	g_return_val_if_fail (E_IS_BOOK_VIEW_LISTENER (listener), NULL);

	if (listener->priv->response_queue == NULL)
		return NULL;

	resp = listener->priv->response_queue->data;

	popped = listener->priv->response_queue;
	listener->priv->response_queue =
		g_list_remove_link (listener->priv->response_queue,
				    listener->priv->response_queue);
	g_list_free_1 (popped);

	return resp;
}

static EBookViewListener *
e_book_view_listener_construct (EBookViewListener *listener)
{
	POA_GNOME_Evolution_Addressbook_BookViewListener *servant;
	CORBA_Environment           ev;
	CORBA_Object                obj;

	g_assert (listener != NULL);
	g_assert (E_IS_BOOK_VIEW_LISTENER (listener));

	servant = (POA_GNOME_Evolution_Addressbook_BookViewListener *) g_new0 (BonoboObjectServant, 1);
	servant->vepv = &e_book_view_listener_vepv;

	CORBA_exception_init (&ev);

	POA_GNOME_Evolution_Addressbook_BookViewListener__init ((PortableServer_Servant) servant, &ev);
	if (ev._major != CORBA_NO_EXCEPTION) {
		g_free (servant);
		CORBA_exception_free (&ev);

		return NULL;
	}

	CORBA_exception_free (&ev);

	obj = bonobo_object_activate_servant (BONOBO_OBJECT (listener), servant);
	if (obj == CORBA_OBJECT_NIL) {
		g_free (servant);

		return NULL;
	}

	bonobo_object_construct (BONOBO_OBJECT (listener), obj);

	return listener;
}

/**
 * e_book_view_listener_new:
 * @book: the #EBookView for which the listener is to be bound
 *
 * Creates and returns a new #EBookViewListener for the book.
 *
 * Returns: a new #EBookViewListener
 */
EBookViewListener *
e_book_view_listener_new ()
{
	EBookViewListener *listener;
	EBookViewListener *retval;

	listener = gtk_type_new (E_BOOK_VIEW_LISTENER_TYPE);

	retval = e_book_view_listener_construct (listener);

	if (retval == NULL) {
		g_warning ("e_book_view_listener_new: Error constructing "
			   "EBookViewListener!\n");
		bonobo_object_unref (BONOBO_OBJECT (listener));
		return NULL;
	}

	return retval;
}

static void
e_book_view_listener_init (EBookViewListener *listener)
{
	listener->priv                 = g_new0 (EBookViewListenerPrivate, 1);
	listener->priv->response_queue = NULL;
	listener->priv->timeout_id     = 0;
	listener->priv->timeout_lock   = FALSE;
	listener->priv->stopped        = FALSE;
}

void
e_book_view_listener_stop (EBookViewListener *listener)
{
	g_return_if_fail (E_IS_BOOK_VIEW_LISTENER (listener));
	listener->priv->stopped = TRUE;
}

static void
e_book_view_listener_destroy (GtkObject *object)
{
	EBookViewListener *listener = E_BOOK_VIEW_LISTENER (object);
	GList *l;
	
	/* Remove our response queue handler: In theory, this can never happen since we
	 always hold a reference to the listener while the timeout is running. */
	if (listener->priv->timeout_id) {
		g_source_remove (listener->priv->timeout_id);
	}

	/* Clear out the queue */
	for (l = listener->priv->response_queue; l != NULL; l = l->next) {
		EBookViewListenerResponse *resp = l->data;

		g_free(resp->id);

		g_list_foreach(resp->cards, (GFunc) gtk_object_unref, NULL);
		g_list_free(resp->cards);
		resp->cards = NULL;

		g_free (resp->message);
		resp->message = NULL;

		g_free (resp);
	}
	g_list_free (listener->priv->response_queue);
	
	g_free (listener->priv);
	listener->priv = NULL;
	
	GTK_OBJECT_CLASS (e_book_view_listener_parent_class)->destroy (object);
}

POA_GNOME_Evolution_Addressbook_BookViewListener__epv *
e_book_view_listener_get_epv (void)
{
	POA_GNOME_Evolution_Addressbook_BookViewListener__epv *epv;

	epv = g_new0 (POA_GNOME_Evolution_Addressbook_BookViewListener__epv, 1);

	epv->notifyCardChanged      = impl_BookViewListener_notify_card_changed;
	epv->notifyCardRemoved      = impl_BookViewListener_notify_card_removed;
	epv->notifyCardAdded        = impl_BookViewListener_notify_card_added;
	epv->notifySequenceComplete = impl_BookViewListener_notify_sequence_complete;
	epv->notifyStatusMessage    = impl_BookViewListener_notify_status_message;

	return epv;
}

static void
e_book_view_listener_corba_class_init (void)
{
	e_book_view_listener_vepv.Bonobo_Unknown_epv          = bonobo_object_get_epv ();
	e_book_view_listener_vepv.GNOME_Evolution_Addressbook_BookViewListener_epv = e_book_view_listener_get_epv ();
}

static void
e_book_view_listener_class_init (EBookViewListenerClass *klass)
{
	GtkObjectClass *object_class = (GtkObjectClass *) klass;

	e_book_view_listener_parent_class = gtk_type_class (bonobo_object_get_type ());

	e_book_view_listener_signals [RESPONSES_QUEUED] =
		gtk_signal_new ("responses_queued",
				GTK_RUN_LAST,
				object_class->type,
				GTK_SIGNAL_OFFSET (EBookViewListenerClass, responses_queued),
				gtk_marshal_NONE__NONE,
				GTK_TYPE_NONE, 0);

	gtk_object_class_add_signals (object_class, e_book_view_listener_signals, LAST_SIGNAL);

	object_class->destroy = e_book_view_listener_destroy;

	e_book_view_listener_corba_class_init ();
}

/**
 * e_book_view_listener_get_type:
 */
GtkType
e_book_view_listener_get_type (void)
{
	static GtkType type = 0;

	if (! type) {
		GtkTypeInfo info = {
			"EBookViewListener",
			sizeof (EBookViewListener),
			sizeof (EBookViewListenerClass),
			(GtkClassInitFunc)  e_book_view_listener_class_init,
			(GtkObjectInitFunc) e_book_view_listener_init,
			NULL, /* reserved 1 */
			NULL, /* reserved 2 */
			(GtkClassInitFunc) NULL
		};

		type = gtk_type_unique (bonobo_object_get_type (), &info);
	}

	return type;
}