Fix download button waiting if document has started but not completed downloading

web/viewer.js

@@ -571,6 +571,8 @@ var PDFView = {
     this.pdfDocument = null;
     var self = this;
     self.loading = true;
+    self.downloadComplete = false;
+
     var passwordNeeded = function passwordNeeded(updatePassword, reason) {
       PasswordPrompt.updatePassword = updatePassword;
       PasswordPrompt.reason = reason;
@@ -622,7 +624,7 @@ var PDFView = {
   },
 
   download: function pdfViewDownload() {
-    function noData() {
+    function downloadByUrl() {
       downloadManager.downloadUrl(url, filename);
     }
 
@@ -636,7 +638,12 @@ var PDFView = {
     };
 
     if (!this.pdfDocument) { // the PDF is not ready yet
-      noData();
+      downloadByUrl();
+      return;
+    }
+
+    if (!this.downloadComplete) { // the PDF is still downloading
+      downloadByUrl();
       return;
     }
 
@@ -645,8 +652,8 @@ var PDFView = {
         var blob = PDFJS.createBlob(data, 'application/pdf');
         downloadManager.download(blob, url, filename);
       },
-      noData // Error occurred try downloading with just the url.
-    ).then(null, noData);
+      downloadByUrl // Error occurred try downloading with just the url.
+    ).then(null, downloadByUrl);
   },
 
   fallback: function pdfViewFallback(featureId) {
@@ -864,6 +871,7 @@ var PDFView = {
     errorWrapper.setAttribute('hidden', 'true');
 
     pdfDocument.getDownloadInfo().then(function() {
+      self.downloadComplete = true;
       PDFView.loadingBar.hide();
       var outerContainer = document.getElementById('outerContainer');
       outerContainer.classList.remove('loadingInProgress');