4 files changed, 150 insertions, 0 deletions

diff --git a/src/common/hexchat.c b/src/common/hexchat.c
index 1aa5fe54..d71a0daa 100644
--- a/src/common/hexchat.c
+++ b/src/common/hexchat.c
@@ -77,6 +77,24 @@ GSList *usermenu_list = 0;
 GSList *urlhandler_list = 0;
 GSList *tabmenu_list = 0;
 
+/*
+ * This array contains 5 double linked lists, one for each priority in the
+ * "interesting session" queue ("channel" stands for everything but
+ * SESS_DIALOG):
+ *
+ * [0] queries with hilight
+ * [1] queries
+ * [2] channels with hilight
+ * [3] channels with dialogue
+ * [4] channels with other data
+ *
+ * Each time activity happens the corresponding session is put at the
+ * beginning of one of the lists.  The aim is to be able to switch to the
+ * session with the most important/recent activity.
+ */
+GList *sess_list_by_lastact[5] = {NULL, NULL, NULL, NULL, NULL};
+
+
 static int in_hexchat_exit = FALSE;
 int hexchat_is_quitting = FALSE;
 /* command-line args */
@@ -103,6 +121,106 @@ SSL_CTX *ctx = NULL;
 pxProxyFactory *libproxy_factory;
 #endif
 
+/*
+ * Update the priority queue of the "interesting sessions"
+ * (sess_list_by_lastact).
+ */
+void
+lastact_update(session *sess)
+{
+	int newidx;
+
+	/* Find the priority (for the order see before) */
+	if (sess->type == SESS_DIALOG)
+	{
+		if (sess->nick_said)
+			newidx = LACT_QUERY_HI;
+		else if (sess->msg_said)
+			newidx = LACT_QUERY;
+		else if (sess->new_data)
+			newidx = LACT_QUERY;
+		else
+			newidx = LACT_NONE;
+	}
+	else
+	{
+		if (sess->nick_said)
+			newidx = LACT_CHAN_HI;
+		else if (sess->msg_said)
+			newidx = LACT_CHAN;
+		else if (sess->new_data)
+			newidx = LACT_CHAN_DATA;		
+		else
+			newidx = LACT_NONE;
+	}
+
+	/* Check if this update is a no-op */
+	if (sess->lastact_idx == newidx && 
+			((newidx != LACT_NONE && sess->lastact_elem == sess_list_by_lastact[newidx]) ||
+			 (newidx == LACT_NONE)))
+		return;
+
+	/* Remove from the old position (and, if no new position, return */
+	else if (sess->lastact_idx != LACT_NONE && sess->lastact_elem)
+	{
+		sess_list_by_lastact[sess->lastact_idx] = g_list_remove_link(
+				sess_list_by_lastact[sess->lastact_idx],
+				sess->lastact_elem);
+		if (newidx == LACT_NONE)
+		{
+			sess->lastact_idx = newidx;
+			return;
+		}
+	}
+
+	/* No previous position, allocate new */
+	else if (!sess->lastact_elem)
+		sess->lastact_elem = g_list_prepend(sess->lastact_elem, sess);
+
+	sess->lastact_idx = newidx;
+	sess_list_by_lastact[newidx] = g_list_concat(
+		sess->lastact_elem, sess_list_by_lastact[newidx]);
+}
+
+/*
+ * Extract the first session from the priority queue of sessions with recent
+ * activity. Return NULL if no such session can be found.
+ *
+ * If filter is specified, skip a session if filter(session) returns 0. This
+ * can be used for UI-specific needs, e.g. in fe-gtk we want to filter out
+ * detached sessions.
+ */
+session *
+lastact_getfirst(int (*filter) (session *sess))
+{
+	int i;
+	session *sess = NULL;
+	GList *curitem;
+
+	/* 5 is the number of priority classes LACT_ */
+	for (i = 0; i < 5 && !sess; i++)
+	{
+		curitem = sess_list_by_lastact[i];
+		while (curitem && !sess)
+		{
+			sess = g_list_nth_data(curitem, 0);
+			if (!sess || (filter && !filter(sess)))
+			{
+				sess = NULL;
+				curitem = g_list_next(curitem);
+			}
+		}
+
+		if (sess)
+		{
+			sess_list_by_lastact[i] = g_list_remove_link(sess_list_by_lastact[i], curitem);
+			sess->lastact_idx = LACT_NONE;
+		}
+	}
+	
+	return sess;
+}
+
 int
 is_session (session * sess)
 {
@@ -372,6 +490,9 @@ session_new (server *serv, char *from, int type, int focus)
 	sess->text_logging = SET_DEFAULT;
 	sess->text_scrollback = SET_DEFAULT;
 
+	sess->lastact_elem = NULL;
+	sess->lastact_idx = LACT_NONE;
+
 	if (from != NULL)
 		safe_strcpy (sess->channel, from, CHANLEN);
 
@@ -525,6 +646,16 @@ session_free (session *killsess)
 	if (killsess->type == SESS_CHANNEL)
 		userlist_free (killsess);
 
+	if (killsess->lastact_elem)
+	{
+		if (killsess->lastact_idx != LACT_NONE)
+				sess_list_by_lastact[killsess->lastact_idx] = g_list_delete_link(
+					sess_list_by_lastact[killsess->lastact_idx],
+					killsess->lastact_elem);
+		else
+			g_list_free_1(killsess->lastact_elem);
+	}
+
 	exec_notify_kill (killsess);
 
 	log_close (killsess);
diff --git a/src/common/hexchat.h b/src/common/hexchat.h
index d84e2761..010414fd 100644
--- a/src/common/hexchat.h
+++ b/src/common/hexchat.h
@@ -348,6 +348,15 @@ struct hexchatprefs
 #define SET_ON 1
 #define SET_DEFAULT 2 /* use global setting */
 
+/* Priorities in the "interesting sessions" priority queue
+ * (see xchat.c:sess_list_by_lastact) */
+#define LACT_NONE		-1		/* no queues */
+#define LACT_QUERY_HI	0		/* query with hilight */
+#define LACT_QUERY		1		/* query with messages */
+#define LACT_CHAN_HI	2		/* channel with hilight */
+#define LACT_CHAN		3		/* channel with messages */
+#define LACT_CHAN_DATA	4		/* channel with other data */
+
 /* Moved from fe-gtk for use in outbound.c as well -- */
 typedef enum gtk_xtext_search_flags_e {
 	case_match = 1,
@@ -406,6 +415,10 @@ typedef struct session
 
 	int type;					/* SESS_* */
 
+	GList *lastact_elem;	/* our GList element in sess_list_by_lastact */
+	int lastact_idx;		/* the sess_list_by_lastact[] index of the list we're in.
+							 * For valid values, see defines of LACT_*. */
+
 	int new_data:1;			/* new data avail? (purple tab) */
 	int nick_said:1;		/* your nick mentioned? (blue tab) */
 	int msg_said:1;			/* new msg available? (red tab) */
diff --git a/src/common/hexchatc.h b/src/common/hexchatc.h
index 207a97cd..9650dc10 100644
--- a/src/common/hexchatc.h
+++ b/src/common/hexchatc.h
@@ -25,10 +25,13 @@ extern GSList *ignore_list;
 extern GSList *usermenu_list;
 extern GSList *urlhandler_list;
 extern GSList *tabmenu_list;
+extern GList *sess_list_by_lastact[];
 
 session * find_channel (server *serv, char *chan);
 session * find_dialog (server *serv, char *nick);
 session * new_ircwindow (server *serv, char *name, int type, int focus);
+void lastact_update (session * sess);
+session * lastact_getfirst (int (*filter) (session *sess));
 int is_session (session * sess);
 void session_free (session *killsess);
 void lag_check (void);
diff --git a/src/common/inbound.c b/src/common/inbound.c
index 7b4c67e8..c86caf24 100644
--- a/src/common/inbound.c
+++ b/src/common/inbound.c
@@ -302,6 +302,7 @@ is_hilight (char *from, char *text, session *sess, server *serv)
 		g_free (text);
 		if (sess != current_tab)
 			sess->nick_said = TRUE;
+			lastact_update (sess);
 		fe_set_hilight (sess);
 		return 1;
 	}
@@ -364,6 +365,7 @@ inbound_action (session *sess, char *chan, char *from, char *ip, char *text, int
 			sess->msg_said = TRUE;
 			sess->new_data = FALSE;
 		}
+		lastact_update (sess);
 	}
 
 	user = userlist_find (sess, from);
@@ -421,6 +423,7 @@ inbound_chanmsg (server *serv, session *sess, char *chan, char *from, char *text
 	{
 		sess->msg_said = TRUE;
 		sess->new_data = FALSE;
+		lastact_update (sess);
 	}
 
 	user = userlist_find (sess, from);