fix image 404 redirect

src/Images/Gallery.coffee

@@ -183,7 +183,7 @@ Gallery =
     error: (file, thumb) ->
       if file.error?.code is MediaError.MEDIA_ERR_DECODE
         return new Notice 'error', 'Corrupt or unplayable video', 30
-      ImageCommon.error g.posts[file.dataset.post], null, ->
+      ImageCommon.error file, g.posts[file.dataset.post], null, (URL) ->
         return unless URL
         thumb.href = URL
         file.src = URL if Gallery.nodes.current is file

src/Images/ImageCommon.coffee

@@ -7,7 +7,10 @@ ImageCommon =
     message.textContent = 'Error: Corrupt or unplayable video'
     return true
 
-  error: (post, delay, cb) ->
+  error: (file, post, delay, cb) ->
+    if (post.isDead or post.file.isDead) and file.src.split('/')[2] is 'i.4cdn.org'
+      ImageCommon.retry post, cb
+
     timeoutID = setTimeout ImageCommon.retry, delay, post, cb if delay?
     return if post.isDead or post.file.isDead
     kill = (fileOnly) ->
@@ -25,6 +28,7 @@ ImageCommon =
     <% } else { %>
     # XXX CORS for i.4cdn.org WHEN?
     $.ajax "//a.4cdn.org/#{post.board}/thread/#{post.thread}.json", onload: ->
+      return kill() if @status is 404
       return if @status isnt 200
       for postObj in @response.posts
         break if postObj.no is post.ID
@@ -37,9 +41,10 @@ ImageCommon =
   retry: (post, cb) ->
     unless post.isDead or post.file.isDead
       return cb post.file.URL + '?' + Date.now()
+    src = post.file.URL.split '/'
     URL = Redirect.to 'file',
       boardID:  post.board.ID
-      filename: post.file.URL
+      filename: src[src.length - 1]
     if URL and (/^https:\/\//.test(URL) or location.protocol is 'http:')
       return cb URL
     cb null # report nothing to retry

src/Images/ImageExpand.coffee

@@ -253,7 +253,7 @@ ImageExpand =
     #  - after the image started loading.
     # Don't try to re-expand if it was already contracted.
     if post.file.isExpanding or post.file.isExpanded
-      ImageCommon.error post, 10 * $.SECOND, (URL) ->
+      ImageCommon.error @, post, 10 * $.SECOND, (URL) ->
         if post.file.isExpanding or post.file.isExpanded
           ImageExpand.contract post
           ImageExpand.expand post, URL if URL

src/Images/ImageHover.coffee

@@ -44,5 +44,4 @@ ImageHover =
     return unless doc.contains @
     post = g.posts[@dataset.fullID]
     return if ImageCommon.decodeError @, post
-    ImageCommon.error post, 3 * $.SECOND, ->
-      @src = URL if URL
+    ImageCommon.error @, post, 3 * $.SECOND, (URL) => @src = URL if URL