fix image error handling

src/Images/ImageCommon.coffee

@@ -1,4 +1,17 @@
 ImageCommon =
+  pushCache: (el) ->
+    ImageCommon.cache = el
+    $.on el, 'error', ImageCommon.cacheError
+
+  popCache: ->
+    el = ImageCommon.cache
+    $.off el, 'error', ImageCommon.cacheError
+    delete ImageCommon.cache
+    el
+
+  cacheError: ->
+    delete ImageCommon.cache if ImageCommon.cache is @
+
   decodeError: (file, post) ->
     return false unless file.error?.code is MediaError.MEDIA_ERR_DECODE
     unless message = $ '.warning', post.file.thumb.parentNode

src/Images/ImageExpand.coffee

@@ -142,7 +142,7 @@ ImageExpand =
           $.off el, eventName, cb
       $.rm el
       $.rmClass el, 'full-image'
-      ImageCommon.cache = el
+      ImageCommon.pushCache el
 
   expand: (post, src) ->
     # Do not expand images of hidden/filtered replies, or already expanded pictures.
@@ -156,8 +156,7 @@ ImageExpand =
     if file.fullImage
       el = file.fullImage
     else if ImageCommon.cache?.dataset.fullID is post.fullID
-      el = file.fullImage = ImageCommon.cache
-      delete ImageCommon.cache
+      el = file.fullImage = ImageCommon.popCache()
       unless file.isHovered
         $.queueTask(-> el.src = el.src) if /\.gif$/.test el.src
         el.currentTime = 0 if isVideo and el.readyState >= el.HAVE_METADATA

src/Images/ImageHover.coffee

@@ -7,23 +7,23 @@ ImageHover =
       cb:   @node
   node: ->
     return unless @file?.isImage or @file?.isVideo
-    $.on @file.thumb, 'mouseover', ImageHover.mouseover
-  mouseover: (e) ->
+    $.on @file.thumb, 'mouseover', ImageHover.mouseover @
+  mouseover: (post) -> (e) ->
     return unless doc.contains @
-    post = Get.postFromNode @
     {file} = post
     {isVideo} = file
     return if file.isExpanding or file.isExpanded
     file.isHovered = true
+    error = ImageHover.error post
     if ImageCommon.cache?.dataset.fullID is post.fullID
-      el = ImageCommon.cache
-      delete ImageCommon.cache
+      el = ImageCommon.popCache()
+      $.on el, 'error', error
       $.queueTask(-> el.src = el.src) if /\.gif$/.test el.src
       el.currentTime = 0 if isVideo and el.readyState >= el.HAVE_METADATA
     else
       el = $.el (if isVideo then 'video' else 'img')
       el.dataset.fullID = post.fullID
-      $.on el, 'error', ImageHover.error
+      $.on el, 'error', error
       el.src = file.URL
     el.id = 'ihover'
     $.after Header.hover, el
@@ -51,19 +51,15 @@ ImageHover =
         if isVideo
           el.pause()
         $.rm el
+        $.off el, 'error', error
         el.removeAttribute 'id'
         el.removeAttribute 'style'
-        ImageCommon.cache = el
+        ImageCommon.pushCache el
         $.queueTask -> delete file.isHovered
-  error: ->
-    post = Get.postFromNode @
-    return if post.file.isExpanding or post.file.isExpanded
-    if @id is 'ihover' # still hovering
-      return if ImageCommon.decodeError @, post
-      ImageCommon.error @, post, 3 * $.SECOND, (URL) =>
-        if URL
-          @src = URL + if @src is URL then '?' + Date.now() else ''
-        else
-          $.rm @
-    else
-      $.rm @
+  error: (post) -> ->
+    return if ImageCommon.decodeError @, post
+    ImageCommon.error @, post, 3 * $.SECOND, (URL) =>
+      if URL
+        @src = URL + if @src is URL then '?' + Date.now() else ''
+      else
+        $.rm @

src/Images/ImageLoader.coffee

@@ -51,7 +51,7 @@ ImageLoader =
     video.dataset.md5 = thumb.dataset.md5
     video.style[attr] = thumb.style[attr] for attr in ['height', 'width', 'maxHeight', 'maxWidth']
     video.src         = file.URL
-    $.on video, 'mouseover', ImageHover.mouseover if Conf['Image Hover']
+    $.on video, 'mouseover', ImageHover.mouseover post if Conf['Image Hover']
     $.replace thumb, video
     file.thumb      = video
     file.videoThumb = true