Add proper download started feedback

* this code adds a cookie when a special get parameter is set
* the content of this get parameter is used as value for the cookie
* the cookie expires after 20 seconds
* the JS code checks every 500 milliseconds for the cookie
  -> if the cookie is set the request returned and the download is started

1 files changed, 23 insertions, 6 deletions

diff --git a/apps/files/js/fileactions.js b/apps/files/js/fileactions.js
index bf529aeb3e8..6678c2d5b34 100644
--- a/apps/files/js/fileactions.js
+++ b/apps/files/js/fileactions.js
@@ -491,14 +491,31 @@
 				var sourceImage = icon.attr('src');
 				icon.attr('src', sourceImage.replace('actions/download.svg', 'loading-small.gif'));
 
-				// TODO proper detection of "download has started"
-				setTimeout(function(){
-					icon.attr('src', sourceImage);
-					downloadFileaction.removeClass('disabled');
-				}, 2000);
+				var randomString = Math.random().toString(36).substring(2);
+
+				var isCookieSet = function(name, value) {
+					var cookies = document.cookie.split(';');
+					for (var i=0; i < cookies.length; i++) {
+						var cookie = cookies[i].split('=');
+						if (cookie[0].trim() === name && cookie[1].trim() === value) {
+							return true;
+						}
+					}
+					return false;
+				};
+
+				var checkForDownloadCookie = function() {
+					if (!isCookieSet('ocDownloadStarted', randomString)){
+						setTimeout(checkForDownloadCookie, 500);
+					} else {
+						icon.attr('src', sourceImage);
+						downloadFileaction.removeClass('disabled');
+					}
+				};
 
 				if (url) {
-					OC.redirect(url);
+					OC.redirect(url + '&downloadStartSecret=' + randomString);
+					checkForDownloadCookie();
 				}
 			}, t('files', 'Download'));
 		}