initial work on topic watch feature: users can stop watching it, but there's no way to start watching unwatched topic

Sources/Post.php

@@ -1346,6 +1346,8 @@ function Post2()
 			$topic = db_insert_id();
 			if ($topic > 0)
 			{
+				// Start watching topic
+				db_query("INSERT IGNORE {$db_prefix}watch_topics(ID_MEMBER,ID_TOPIC) VALUES($ID_MEMBER,$topic);", __FILE__, __LINE__);
 				// Fix the message with the topic.
 				db_query("
 					UPDATE {$db_prefix}messages
@@ -1390,6 +1392,10 @@ function Post2()
 				'$user_info[ip]', " . (isset($_POST['ns']) ? '0' : '1') . ", '$_POST[message]', '$_POST[icon]')", __FILE__, __LINE__);
 		$ID_MSG = db_insert_id();
 
+		// If this is the first time user replies in this topic,
+		// he'll start watching it.
+		db_query("INSERT IGNORE {$db_prefix}watch_topics(ID_MEMBER,ID_TOPIC) VALUES($ID_MEMBER,$topic);", __FILE__, __LINE__);
+
 		if ($ID_MSG > 0)
 		{
 			// If attachments were added, update the table now we know the message ID.

Sources/Recent.php

@@ -128,7 +128,48 @@ function getLastPosts($showlatestcount)
 
 	return $posts;
 }
+// Watch topic updates
+function WatchTopic()
+{
+	global $txt, $scripturl, $db_prefix, $user_info, $context, $ID_MEMBER, $modSettings, $sourcedir;
+	if ( ! (isset ($_GET['id_topic']) AND ctype_digit($_GET['id_topic']))) {
+		redirectexit('');
+	}
+	$r = db_query("SELECT * FROM {$db_prefix}topics WHERE ID_TOPIC={$_GET['id_topic']}", __FILE__, __LINE__);
+	
+	// somebody uncool passed non-existent topic ID
+	if (mysql_num_rows($r) != 1) {
+		redirectexit('');
+	}
 
+	// Okay, the topic exists, start watching it
+	db_query("REPLACE INTO {$db_prefix}watch_topics VALUES('$ID_MEMBER','{$_GET['id_topic']}',1);", __FILE__, __LINE__);
+
+	$return = isset($_GET['return']) ? urldecode($_GET['return']) : '';
+	redirectexit($return);
+	
+}
+// Stop watching topic updates
+function UnwatchTopic()
+{
+	global $txt, $scripturl, $db_prefix, $user_info, $context, $ID_MEMBER, $modSettings, $sourcedir;
+	if ( ! (isset ($_GET['id_topic']) AND ctype_digit($_GET['id_topic']))) {
+		redirectexit('');
+	}
+	$r = db_query("SELECT * FROM {$db_prefix}topics WHERE ID_TOPIC={$_GET['id_topic']}", __FILE__, __LINE__);
+	
+	// somebody uncool passed non-existent topic ID
+	if (mysql_num_rows($r) != 1) {
+		redirectexit('');
+	}
+
+	// Okay, the topic exists, remove topic from watch list
+	db_query("REPLACE INTO {$db_prefix}watch_topics VALUES('$ID_MEMBER','{$_GET['id_topic']}',0);", __FILE__, __LINE__);
+
+	$return = isset($_GET['return']) ? urldecode($_GET['return']) : '';
+	redirectexit($return);
+	
+}
 // Find the ten most recent posts.
 function RecentPosts()
 {
@@ -455,10 +496,11 @@ function UnreadTopics()
 
 		$request = db_query("
 			SELECT DISTINCT t.ID_TOPIC
-			FROM ({$db_prefix}topics AS t, {$db_prefix}boards AS b, {$db_prefix}messages AS ml, {$db_prefix}messages AS m)
+			FROM ({$db_prefix}topics AS t, {$db_prefix}boards AS b, {$db_prefix}messages AS ml, {$db_prefix}messages AS m, {$db_prefix}watch_topics as w)
 				LEFT JOIN {$db_prefix}log_topics AS lt ON (lt.ID_TOPIC = t.ID_TOPIC AND lt.ID_MEMBER = $ID_MEMBER)
 				LEFT JOIN {$db_prefix}log_mark_read AS lmr ON (lmr.ID_BOARD = b.ID_BOARD AND lmr.ID_MEMBER = $ID_MEMBER)
 			WHERE ml.ID_MEMBER != $ID_MEMBER
+				AND w.ID_TOPIC=t.ID_TOPIC AND w.ID_MEMBER=$ID_MEMBER AND w.watch=1
 				AND m.ID_TOPIC = t.ID_TOPIC
 				AND m.ID_MEMBER = $ID_MEMBER
 				AND ml.ID_MSG = t.ID_LAST_MSG

Themes/default/Recent.template.php

@@ -228,7 +228,7 @@ function template_replies()
 					<img src="' . $settings['images_url'] . '/post/' . $topic['first_post']['icon'] . '.gif" alt="" border="0" align="middle" /></td>
 				<td class="windowbg" valign="middle" width="48%">
 					' . $topic['first_post']['link'] . ' <a href="' . $scripturl . '?topic=' . $topic['id'] . '.from' . $topic['newtime'] . ';topicseen#new"><img src="' . $settings['images_url'] . '/' . $context['user']['language'] . '/new.gif" alt="' . $txt[302] . '" border="0" /></a> <span class="smalltext">' . $topic['pages'] . '</span>
-					<div class="smalltext"><i>' . $txt['smf88'] . ' ' . $topic['board']['link'] . '</i></div></td>
+					<div class="smalltext"><i>' . $txt['smf88'] . ' ' . $topic['board']['link'] . '</i><div style="float: right;"><a style="color: gray;" href="'.$scripturl.'?action=unwatch;id_topic='.$topic['id'].';return='.urlencode($_SERVER['QUERY_STRING']).'">Не следить</a></div></div></td>
 				<td class="windowbg" valign="middle" width="4%" align="center">
 					' . $topic['replies']. '</td>
 				<td class="windowbg2" valign="middle" width="22%">';

index.php

@@ -330,6 +330,8 @@ function smf_main()
 		'warnlist2' => array('VisualWarning.php', 'ListWarnings2'),
 		'warnpmman' => array('VisualWarning.php', 'Manager'),
 		'warnpmman2' => array('VisualWarning.php', 'Manager2'),
+		'watch' => array('Recent.php', 'WatchTopic'),
+		'unwatch' => array('Recent.php', 'UnwatchTopic'),
 		'who' => array('Who.php', 'Who'),
 		'.kml' => array('GoogleMap.php', 'ShowKML'),
 		'.xml' => array('News.php', 'ShowXmlFeed'),