Add a processURL hook

This is useful when the URL from _get_URL() is the URL of some middle
resource, like an ASX file, providing the actual URL of the content we
want to Direct Link.

Signed-off-by: Antonio Ospite <ospite@studenti.unina.it>

diff --git a/direct_download_links.user.js b/direct_download_links.user.js
index 418b3a5..eb4175a 100644 (file)
--- a/direct_download_links.user.js
+++ b/direct_download_links.user.js
@@ -62,6 +62,11 @@
  *              targetElement: the element in the event handler we want the
  *                urlRegexp is performed on.
  *
+ *  processURL: a function to process the URL before adding the Direct
+ *              Downdload Link to the page, it must accept  a 'site' and a
+ *              'URL' parameters and dispatch the UrlFetched to pass the
+ *              modified URL to _add_link().
+ *
  */
 var supported_sites = [
   {
@@ -93,6 +98,7 @@ var supported_sites = [
     urlContainer: 'Player',
     urlRegexp: /mediaUri=(http:\/\/[^,]*)/,
     onEvent: { evt: 'DOMNodeInserted', targetElement: 'object' },
+    processURL: _rai_get_actual_url,
     linkDest: 'Player',
   },
 ];
@@ -157,6 +163,11 @@ function _get_URL(site, element) {
     return;
   }
 
+  if (site.processURL) {
+    site.processURL(site, URL);
+    return;
+  }
+
   var evt = document.createEvent('Event');  
   evt.initEvent('UrlFetched', true, true);  
   evt.site = site;
@@ -194,3 +205,33 @@ function DDL_log(message) {
     GM_log(message);
   }
 }
+
+function _rai_get_actual_url(site, URL) {
+  // http://www.neaveru.com/wordpress/index.php/2008/05/09/greasemonkey-bug-domnodeinserted-event-doesnt-allow-gm_xmlhttprequest/
+  setTimeout( function() {
+    GM_xmlhttpRequest({
+      method: "GET",
+      // XXX A custom header. This is the "clever" trick Rai uses to ensure
+      // the content is accessed by www.rai.tv only...
+      headers: {'viaurl': 'www.rai.tv'},
+      url: URL,
+      onload: function(response) {
+        text = response.responseText;
+        text = text.replace(/&/g, '&')
+        parser = new DOMParser();
+        xmlDoc = parser.parseFromString(text, "text/xml");
+
+        ref = xmlDoc.getElementsByTagName('REF');
+        if (ref.length > 0) {
+          href = ref[0].getAttribute('HREF');;
+
+          var evt = document.createEvent('Event');  
+          evt.initEvent('UrlFetched', true, true);  
+          evt.site = site;
+          evt.URL = href;
+          document.dispatchEvent(evt);
+        }
+      }
+    });
+  }, 0);
+}