From d6ca563f46aef012e534b2a0c1ab0d84afbeaf7f Mon Sep 17 00:00:00 2001
From: Jonas Jenwald <jonas.jenwald@gmail.com>
Date: Mon, 10 Feb 2014 13:43:26 +0100
Subject: [PATCH] Fix wrong page being displayed when entering/exiting
 Presentation mode with zoom set to 'page-fit'

---
 web/page_view.js |  7 ++++++-
 web/viewer.js    | 20 +++++++++++++++-----
 2 files changed, 21 insertions(+), 6 deletions(-)

diff --git a/web/page_view.js b/web/page_view.js
index a02864f06..a0de5d8f5 100644
--- a/web/page_view.js
+++ b/web/page_view.js
@@ -329,7 +329,12 @@ var PageView = function pageView(container, id, scale,
   };
 
   this.scrollIntoView = function pageViewScrollIntoView(dest) {
-    if (PresentationMode.active) { // Avoid breaking presentation mode.
+    if (PresentationMode.active) {
+      if (PDFView.page !== this.id) {
+        // Avoid breaking PDFView.getVisiblePages in presentation mode.
+        PDFView.page = this.id;
+        return;
+      }
       dest = null;
       PDFView.setScale(PDFView.currentScaleValue, true, true);
     }
diff --git a/web/viewer.js b/web/viewer.js
index e5ce5b422..cd6b720ee 100644
--- a/web/viewer.js
+++ b/web/viewer.js
@@ -1321,8 +1321,16 @@ var PDFView = {
   },
 
   getVisiblePages: function pdfViewGetVisiblePages() {
-    return this.getVisibleElements(this.container, this.pages,
-                                   !PresentationMode.active);
+    if (!PresentationMode.active) {
+      return this.getVisibleElements(this.container, this.pages, true);
+    } else {
+      // The algorithm in getVisibleElements doesn't work in all browsers and
+      // configurations when presentation mode is active.
+      var visible = [];
+      var currentPage = this.pages[this.page - 1];
+      visible.push({ id: currentPage.id, view: currentPage });
+      return { first: currentPage, last: currentPage, views: visible };
+    }
   },
 
   getVisibleThumbs: function pdfViewGetVisibleThumbs() {
@@ -1869,9 +1877,11 @@ function updateViewarea() {
     currentId = visiblePages[0].id;
   }
 
-  updateViewarea.inProgress = true; // used in "set page"
-  PDFView.page = currentId;
-  updateViewarea.inProgress = false;
+  if (!PresentationMode.active) {
+    updateViewarea.inProgress = true; // used in "set page"
+    PDFView.page = currentId;
+    updateViewarea.inProgress = false;
+  }
 
   var currentScale = PDFView.currentScale;
   var currentScaleValue = PDFView.currentScaleValue;