implement unfollow thread

include/conversation.php

@@ -917,6 +917,9 @@ function item_photo_menu($item){
 		if($item['parent'] == $item['id'] && $channel && ($channel_hash != $item['author_xchan'])) {
 			$sub_link = 'javascript:dosubthread(' . $item['id'] . '); return false;';
 		}
+		if($channel) {
+			$unsub_link = 'javascript:dounsubthread(' . $item['id'] . '); return false;';
+		}
 	}
 
 	$profile_link = chanlink_hash($item['author_xchan']);
@@ -941,6 +944,7 @@ function item_photo_menu($item){
 	$menu = Array(
 		t("View Source") => $vsrc_link,
 		t("Follow Thread") => $sub_link,
+		t("Stop Following") => $unsub_link,
 		t("View Status") => $status_link,
 		t("View Profile") => $profile_link,
 		t("View Photos") => $photos_link,

include/items.php

@@ -2837,6 +2837,8 @@ function store_diaspora_comment_sig($datarray, $channel, $parent_item, $post_id,
 function send_status_notifications($post_id,$item) {
 
 	$notify = false;
+	$unfollowed = false;
+
 	$parent = 0;
 
 	$r = q("select channel_hash from channel where channel_id = %d limit 1",
@@ -2864,6 +2866,14 @@ function send_status_notifications($post_id,$item) {
 		foreach($x as $xx) {
 			if($xx['author_xchan'] === $r[0]['channel_hash']) {
 				$notify = true;
+
+				// check for an unfollow thread activity - we should probably decode the obj and check the id
+				// but it will be extremely rare for this to be wrong.
+
+				if(($xx['verb'] === ACTIVITY_UNFOLLOW) 
+					&& ($xx['obj_type'] === ACTIVITY_OBJ_NOTE || $xx['obj_type'] === ACTIVITY_OBJ_PHOTO) 
+					&& ($xx['parent'] != $xx['id']))
+					$unfollowed = true;				
 			}
 			if($xx['id'] == $xx['parent']) {
 				$parent = $xx['parent'];
@@ -2871,6 +2881,9 @@ function send_status_notifications($post_id,$item) {
 		}
 	}
 
+	if($unfollowed)
+		return;
+
 	$link =  get_app()->get_baseurl() . '/display/' . $item['mid'];
 
 	$y = q("select id from notify where link = '%s' and uid = %d limit 1",