Engine for live queries to calendars. A query object watches a CalBackend

2001-03-29  Federico Mena Quintero  <federico@ximian.com>

	Engine for live queries to calendars.  A query object watches a
	CalBackend in the PCS and is otherwise completely separate from
	it; backends need to do nothing to support live queries.  Right
	now we have the following functions:

		(get-vtype)

			Returns a string indicating the type of component
			(VEVENT, VTODO, VJOURNAL, VFREEBUSY, VTIMEZONE,
			UNKNOWN).

		(occur-in-time-range? START END)

			START - int, time_t start of the time range
			END - int, time_t end of the time range

			Returns a boolean indicating whether the component
			has any occurrences in the specified time range.

	* idl/evolution-calendar.idl (Cal::getQuery): New method that
	initiates a live query.
	(Query): New interface for a handle to a live query.
	(QueryListener): New interface for a listener to changes in a live
	query.

	* pcs/query.[ch]: New files with the live query engine.

	* pcs/cal-backend.h (CalBackendClass): Added notification signals
	so that the query system can catch them.
	(CalBackendClass): New virtual method ::get_load_state().

	* pcs/cal-backend.c (cal_backend_opened):
	(cal_backend_obj_updated):
	(cal_backend_obj_updated): New functions to emit the notification
	signals; to be used only by backend implementations.
	(cal_backend_get_load_state): New function.

	* pcs/cal-backend-file.c (notify_update): Call
	cal_backend_obj_updated().
	(notify_remove): Call call_backend_obj_removed().
	(open_cal): Free the icalcomp if it is not of the correct type.
	(cal_backend_file_get_load_state): Implemented new method.

	* pcs/cal-backend-db.c (cal_backend_db_update_object): Call
	cal_backend_obj_updated().
	(cal_backend_db_remove_object): Call cal_backend_obj_removed().
	(cal_backend_db_get_load_state): Implemented new method.

	* pcs/cal.c (Cal_get_query): Implementation of the ::getQuery()
	method.

svn path=/trunk/; revision=9013

1 files changed, 16 insertions, 1 deletions

diff --git a/calendar/pcs/cal-backend-db.c b/calendar/pcs/cal-backend-db.c
index fca87bd9ab..d4773760f8 100644
--- a/calendar/pcs/cal-backend-db.c
+++ b/calendar/pcs/cal-backend-db.c
@@ -67,6 +67,7 @@ static void cal_backend_db_add_cal (CalBackend *backend, Cal *cal);
 static CalBackendOpenStatus cal_backend_db_open (CalBackend *backend,
                                                  GnomeVFSURI *uri,
                                                  gboolean only_if_exists);
+static gboolean cal_backend_db_is_loaded (CalBackend *backend);
 
 static int cal_backend_db_get_n_objects (CalBackend *backend, CalObjType type);
 static char *cal_backend_db_get_object (CalBackend *backend, const char *uid);
@@ -150,6 +151,7 @@ cal_backend_db_class_init (CalBackendDBClass *klass)
 	backend_class->get_uri = cal_backend_db_get_uri;
 	backend_class->add_cal = cal_backend_db_add_cal;
 	backend_class->open = cal_backend_db_open;
+	backend_class->is_loaded = cal_backend_db_is_loaded;
 	backend_class->get_n_objects = cal_backend_db_get_n_objects;
 	backend_class->get_object = cal_backend_db_get_object;
 	backend_class->get_type_by_uid = cal_backend_db_get_type_by_uid;
@@ -589,6 +591,17 @@ cal_backend_db_open (CalBackend *backend, GnomeVFSURI *uri, gboolean only_if_exi
 	return CAL_BACKEND_OPEN_SUCCESS;
 }
 
+/* is_loaded handler for the DB backend */
+static gboolean
+cal_backend_db_is_loaded (CalBackend *backend)
+{
+	CalBackendDB *cbdb;
+
+	cbdb = CAL_BACKEND_DB (backend);
+
+	return (cbdb->priv->uri != NULL);
+}
+
 /* get_n_objects handler for the DB backend */
 static int
 cal_backend_db_get_n_objects (CalBackend *backend, CalObjType type)
@@ -1445,7 +1458,8 @@ cal_backend_db_update_object (CalBackend *backend, const char *uid, const char *
 		return FALSE;
 	}
 	commit_transaction(tid);
-	
+
+	cal_backend_obj_updated (CAL_BACKEND (cbdb), uid);
 	do_notify(cbdb, cal_notify_update, uid);
 	return TRUE;
 }
@@ -1482,6 +1496,7 @@ cal_backend_db_remove_object (CalBackend *backend, const char *uid)
 	/* TODO: update history database */
 	commit_transaction(tid);
 	
+	cal_backend_obj_removed (CAL_BACKEND (cbdb), uid);
 	do_notify(cbdb, cal_notify_remove, uid);
 			
 	return TRUE;