/*
   ** Caching photos urls on save
   */
   add_action("save_post", function($post_id){
      if (get_current_screen()->post_type == "post"){
         // Reset
         if (!empty(get_post_meta($post_id, "cachedPhotos")))
            delete_post_meta($post_id, "cachedPhotos");

         $i = 0;
         $photosToChange = array();

         // Get photos
         $checkPhotos = get_post_meta($post_id, "cachedPhotos");

         // Process
         $content = get_post($post_id)->post_content;
         $pattern = get_shortcode_regex();
         preg_match_all("/".$pattern."/s", $content, $shortcodes);

         foreach ($shortcodes[0] as $photo){
            // ID
            preg_match_all('/id="([^"]+)"/', $photo, $id);
            if (isset($id[1][0])){
               $id = $id[1][0];
               $photosToChange[$i]["id"] = $id;
            }
            // Caption
            preg_match_all('/caption="([^"]+)"/', $photo, $caption);
            if (isset($caption[1][0])){
               $caption = $caption[1][0];
               $photosToChange[$i]["caption"] = $caption;
            }

            // If the ID is not empty
            if (isset($id[1][0])){
               // Flickr
               if (preg_match("/^\d{11}$/", $id)){
                  $flickrJSON = file_get_contents("http://api.flickr.com/services/rest/?method=flickr.photos.getSizes&api_key=curiousyouare&photo_id={$id}&format=json&nojsoncallback=1");
                  $photosToChange[$i]["link"] = "http://flickr.com/photos/fpeault/{$id}";
                  $photosToChange[$i]["src"] = json_decode($flickrJSON)->sizes->size[7]->source;
               }
               // Instagram
               elseif (preg_match("/([a-zA-Z0-9_-]){10}/", $id)){
                  $igJSON = file_get_contents("http://api.instagram.com/oembed?url=http://instagram.com/p/{$id}");
                  $photosToChange[$i]["link"] = "http://instagram.com/p/{$id}";
                  $photosToChange[$i]["src"] = json_decode($igJSON)->url;
               }
            }
            $i++;
         }
         add_post_meta($post_id, "cachedPhotos", $photosToChange);
      }
   });