public static function isUserAttentedTopic(User $user, Topic $topic)
{
return Attention::where('user_id', $user->id)->where('topic_id', $topic->id)->first();
}
public static function unfollow($from, $to)
{
$attention = Attention::where('u_fans_id', '=', $from->u_id)->where('u_id', '=', $to->u_id)->first();
if (!isset($attention->a_id)) {
return true;
}
if (!$attention->delete()) {
throw new Exception("取消关注失败", 1);
}
$from->u_following_count -= 1;
if ($from->u_following_count <= 0) {
$from->u_following_count = 0;
}
$to->u_follower_count -= 1;
if ($to->u_follower_count <= 0) {
$to->u_follower_count = 0;
}
if ($from->save() && $to->save()) {
return true;
} else {
throw new Exception("取消关注失败", 1);
}
}
