catchup in category view mode jumps to the next unread category

feedlist.js

@@ -135,6 +135,12 @@ function viewfeed(feed, subop, is_cat, subop_param, skip_history, offset) {
 
 		if (subop == "MarkAllRead") {
 
+			var show_next_feed = getInitParam("on_catchup_show_next_feed") == "1";
+
+			if (show_next_feed) {
+
+				if (!activeFeedIsCat()) {
+	
 					var feedlist = document.getElementById('feedList');
 				
 					var next_unread_feed = getRelativeFeedId(feedlist,
@@ -145,13 +151,26 @@ function viewfeed(feed, subop, is_cat, subop_param, skip_history, offset) {
 							-3, "next", true);
 					}
 		
-			var show_next_feed = getInitParam("on_catchup_show_next_feed") == "1";
+					if (next_unread_feed) {
-
-			if (next_unread_feed && show_next_feed && !activeFeedIsCat()) {
 						query = query + "&nuf=" + param_escape(next_unread_feed);
 						//setActiveFeedId(next_unread_feed);
 						feed = next_unread_feed;
 					}
+				} else {
+	
+					var next_unread_feed = getNextUnreadCat(feed);
+
+					/* we don't need to specify that our next feed is actually
+					a category, because we're in the is_cat mode by definition
+					already */
+
+					if (next_unread_feed && show_next_feed) {
+						query = query + "&nuf=" + param_escape(next_unread_feed);
+						feed = next_unread_feed;
+					}
+
+				}
+			}
 		}
 
 		if (is_cat) {

functions.js

@@ -1035,6 +1035,40 @@ function toggleSelectRow(sender) {
 	}
 }
 
+function getNextUnreadCat(id) {
+	try {
+		var rows = document.getElementById("feedList").getElementsByTagName("LI");
+		var feeds = new Array();
+
+		var unread_only = true;
+		var is_cat = true;
+
+		for (var i = 0; i < rows.length; i++) {
+			if (rows[i].id.match("FCAT-")) {
+				if (rows[i].id == "FCAT-" + id && is_cat || (Element.visible(rows[i]) && Element.visible(rows[i].parentNode))) {
+
+					var cat_id = parseInt(rows[i].id.replace("FCAT-", ""));
+
+					if (cat_id >= 0) {
+						if (!unread_only || get_cat_unread(cat_id) > 0) {
+							feeds.push(cat_id);
+						}
+					}
+				}
+			}
+		}
+
+		var idx = feeds.indexOf(id);
+		if (idx != -1 && idx < feeds.length) {
+			return feeds[idx+1];					
+		} else {
+			return feeds.shift();
+		}
+
+	} catch (e) {
+		exception_error("getNextUnreadCat", e);
+	}
+}
 
 function getRelativeFeedId2(id, is_cat, direction, unread_only) {	
 	try {