Merge pull request #990 from notmasteryet/concurload

Fixes concurrent pages loading (#974 and #626)

src/core.js

@@ -527,6 +527,13 @@ var PDFDocModel = (function PDFDocModelClosure() {
                            this.startXRef,
                            this.mainXRefEntriesOffset);
       this.catalog = new Catalog(this.xref);
+      if (this.xref.trailer && this.xref.trailer.has('ID')) {
+        var fileID = '';
+        this.xref.trailer.get('ID')[0].split('').forEach(function(el) {
+          fileID += Number(el.charCodeAt(0)).toString(16);
+        });
+        this.fileID = fileID;
+      }
     },
     get numPages() {
       var linearization = this.linearization;
@@ -534,6 +541,22 @@ var PDFDocModel = (function PDFDocModelClosure() {
       // shadow the prototype getter
       return shadow(this, 'numPages', num);
     },
+    getFingerprint: function pdfDocGetFingerprint() {
+      if (this.fileID) {
+        return this.fileID;
+      } else {
+        // If we got no fileID, then we generate one,
+        // from the first 100 bytes of PDF
+        var data = this.stream.bytes.subarray(0, 100);
+        var hash = calculateMD5(data, 0, data.length);
+        var strHash = '';
+        for (var i = 0, length = hash.length; i < length; i++) {
+          strHash += Number(hash[i]).toString(16);
+        }
+
+        return strHash;
+      }
+    },
     getPage: function pdfDocGetPage(n) {
       return this.catalog.getPage(n);
     }
@@ -560,7 +583,7 @@ var PDFDoc = (function PDFDocClosure() {
     this.data = data;
     this.stream = stream;
     this.pdf = new PDFDocModel(stream);
-
+    this.fingerprint = this.pdf.getFingerprint();
     this.catalog = this.pdf.catalog;
     this.objs = new PDFObjects();
 

src/obj.js

@@ -269,7 +269,7 @@ var XRef = (function XRefClosure() {
     this.entries = [];
     this.xrefstms = {};
     var trailerDict = this.readXRef(startXRef);
-
+    this.trailer = trailerDict;
     // prepare the XRef cache
     this.cache = [];
 

web/viewer.js

@@ -12,6 +12,7 @@ var kScrollbarPadding = 40;
 var kMinScale = 0.25;
 var kMaxScale = 4.0;
 var kImageDirectory = './images/';
+var kSettingsMemory = 20;
 
 var Cache = function cacheCache(size) {
   var data = [];
@@ -25,13 +26,126 @@ var Cache = function cacheCache(size) {
   };
 };
 
+var RenderingQueue = (function RenderingQueueClosure() {
+  function RenderingQueue() {
+    this.items = [];
+  }
+
+  RenderingQueue.prototype = {
+    enqueueDraw: function RenderingQueueEnqueueDraw(item) {
+      if ('rendering' in item)
+        return; // is already in the queue
+
+      item.rendering = true;
+      this.items.push(item);
+      if (this.items.length > 1)
+        return; // not first item
+
+      item.draw(this.continueExecution.bind(this));
+    },
+    continueExecution: function RenderingQueueContinueExecution() {
+      var item = this.items.shift();
+      delete item.rendering;
+
+      if (this.items.length == 0)
+        return; // queue is empty
+
+      item = this.items[0];
+      item.draw(this.continueExecution.bind(this));
+    }
+  };
+
+  return RenderingQueue;
+})();
+
+// Settings Manager - This is a utility for saving settings
+// First we see if localStorage is available, FF bug #495747
+// If not, we use FUEL in FF
+var Settings = (function SettingsClosure() {
+  var isLocalStorageEnabled = (function localStorageEnabledTest() {
+    try {
+      localStorage;
+    } catch (e) {
+      return false;
+    }
+    return true;
+  })();
+  var extPrefix = 'extensions.uriloader@pdf.js';
+  var isExtension = location.protocol == 'chrome:' && !isLocalStorageEnabled;
+  var inPrivateBrowsing = false;
+  if (isExtension) {
+    var pbs = Components.classes['@mozilla.org/privatebrowsing;1']
+              .getService(Components.interfaces.nsIPrivateBrowsingService);
+    inPrivateBrowsing = pbs.privateBrowsingEnabled;
+  }
+
+  function Settings(fingerprint) {
+    var database = null;
+    var index;
+    if (inPrivateBrowsing)
+      return false;
+    else if (isExtension)
+      database = Application.prefs.getValue(extPrefix + '.database', '{}');
+    else if (isLocalStorageEnabled)
+      database = localStorage.getItem('database') || '{}';
+    else
+      return false;
+
+    database = JSON.parse(database);
+    if (!('files' in database))
+      database.files = [];
+    if (database.files.length >= kSettingsMemory)
+      database.files.shift();
+    for (var i = 0, length = database.files.length; i < length; i++) {
+      var branch = database.files[i];
+      if (branch.fingerprint == fingerprint) {
+        index = i;
+        break;
+      }
+    }
+    if (typeof index != 'number')
+      index = database.files.push({fingerprint: fingerprint}) - 1;
+    this.file = database.files[index];
+    this.database = database;
+    if (isExtension)
+      Application.prefs.setValue(extPrefix + '.database',
+          JSON.stringify(database));
+    else if (isLocalStorageEnabled)
+      localStorage.setItem('database', JSON.stringify(database));
+  }
+
+  Settings.prototype = {
+    set: function settingsSet(name, val) {
+      if (inPrivateBrowsing)
+        return false;
+      var file = this.file;
+      file[name] = val;
+      if (isExtension)
+        Application.prefs.setValue(extPrefix + '.database',
+            JSON.stringify(this.database));
+      else if (isLocalStorageEnabled)
+        localStorage.setItem('database', JSON.stringify(this.database));
+    },
+
+    get: function settingsGet(name, defaultValue) {
+      if (inPrivateBrowsing)
+        return defaultValue;
+      else
+        return this.file[name] || defaultValue;
+    }
+  };
+
+  return Settings;
+})();
+
 var cache = new Cache(kCacheSize);
+var renderingQueue = new RenderingQueue();
 var currentPageNumber = 1;
 
 var PDFView = {
   pages: [],
   thumbnails: [],
-  currentScale: kDefaultScale,
+  currentScale: 0,
   initialBookmark: document.location.hash.substring(1),
 
   setScale: function pdfViewSetScale(val, resetAutoSettings) {
@@ -272,8 +386,20 @@ var PDFView = {
       this.error('An error occurred while reading the PDF.', e);
     }
     var pagesCount = pdf.numPages;
+    var id = pdf.fingerprint;
+    var storedHash = null;
     document.getElementById('numPages').innerHTML = pagesCount;
     document.getElementById('pageNumber').max = pagesCount;
+    PDFView.documentFingerprint = id;
+    var store = PDFView.store = new Settings(id);
+    if (store.get('exists', false)) {
+      var page = store.get('page', '1');
+      var zoom = store.get('zoom', PDFView.currentScale);
+      var left = store.get('scrollLeft', '0');
+      var top = store.get('scrollTop', '0');
+
+      storedHash = 'page=' + page + '&zoom=' + zoom + ',' + left + ',' + top;
+    }
 
     var pages = this.pages = [];
     var pagesRefMap = {};
@@ -294,7 +420,6 @@ var PDFView = {
 
     this.pagesRefMap = pagesRefMap;
     this.destinations = pdf.catalog.destinations;
-    this.setScale(scale || kDefaultScale, true);
 
     if (pdf.catalog.documentOutline) {
       this.outline = new DocumentOutlineView(pdf.catalog.documentOutline);
@@ -307,8 +432,12 @@ var PDFView = {
       this.setHash(this.initialBookmark);
       this.initialBookmark = null;
     }
-    else
+    else if (storedHash)
+      this.setHash(storedHash);
+    else {
+      this.setScale(scale || kDefaultScale, true);
       this.page = 1;
+    }
   },
 
   setHash: function pdfViewSetHash(hash) {
@@ -334,7 +463,7 @@ var PDFView = {
         if ('zoom' in params) {
           var zoomArgs = params.zoom.split(','); // scale,left,top
           // building destination array
-          var dest = [null, new Name('XYZ'), (zoomArgs[1] | 0),
+          var dest = [null, {name: 'XYZ'}, (zoomArgs[1] | 0),
             (zoomArgs[2] | 0), (zoomArgs[0] | 0) / 100];
           var currentPage = this.pages[pageNumber - 1];
           currentPage.scrollIntoView(dest);
@@ -609,10 +738,11 @@ var PageView = function pageView(container, content, id, pageWidth, pageHeight,
       }, 0);
   };
 
-  this.draw = function pageviewDraw() {
+  this.draw = function pageviewDraw(callback) {
     if (div.hasChildNodes()) {
       this.updateStats();
-      return false;
+      callback();
+      return;
     }
 
     var canvas = document.createElement('canvas');
@@ -644,13 +774,14 @@ var PageView = function pageView(container, content, id, pageWidth, pageHeight,
         this.updateStats();
         if (this.onAfterDraw)
           this.onAfterDraw();
+
+        cache.push(this);
+        callback();
       }).bind(this), textLayer
     );
 
     setupAnnotations(this.content, this.scale);
     div.setAttribute('data-loaded', true);
-
-    return true;
   };
 
   this.updateStats = function pageViewUpdateStats() {
@@ -717,12 +848,16 @@ var ThumbnailView = function thumbnailView(container, page, id, pageRatio) {
     return ctx;
   }
 
-  this.draw = function thumbnailViewDraw() {
+  this.draw = function thumbnailViewDraw(callback) {
-    if (this.hasImage)
+    if (this.hasImage) {
+      callback();
       return;
+    }
 
     var ctx = getPageDrawContext();
-    page.startRendering(ctx, function thumbnailViewDrawStartRendering() {});
+    page.startRendering(ctx, function thumbnailViewDrawStartRendering() {
+      callback();
+    });
 
     this.hasImage = true;
   };
@@ -805,8 +940,7 @@ function updateViewarea() {
   var visiblePages = PDFView.getVisiblePages();
   for (var i = 0; i < visiblePages.length; i++) {
     var page = visiblePages[i];
-    if (PDFView.pages[page.id - 1].draw())
+    renderingQueue.enqueueDraw(PDFView.pages[page.id - 1]);
-      cache.push(page.view);
   }
 
   if (!visiblePages.length)
@@ -826,6 +960,14 @@ function updateViewarea() {
   var topLeft = currentPage.getPagePoint(window.pageXOffset,
     window.pageYOffset - firstPage.y - kViewerTopMargin);
   pdfOpenParams += ',' + Math.round(topLeft.x) + ',' + Math.round(topLeft.y);
+
+  var store = PDFView.store;
+  store.set('exists', true);
+  store.set('page', pageNumber);
+  store.set('zoom', Math.round(PDFView.currentScale * 100));
+  store.set('scrollLeft', Math.round(topLeft.x));
+  store.set('scrollTop', Math.round(topLeft.y));
+
   document.getElementById('viewBookmark').href = pdfOpenParams;
 }
 
@@ -848,7 +990,7 @@ function updateThumbViewArea() {
     var visibleThumbs = PDFView.getVisibleThumbs();
     for (var i = 0; i < visibleThumbs.length; i++) {
       var thumb = visibleThumbs[i];
-      PDFView.thumbnails[thumb.id - 1].draw();
+      renderingQueue.enqueueDraw(PDFView.thumbnails[thumb.id - 1]);
     }
   }, delay);
 }
@@ -888,7 +1030,6 @@ window.addEventListener('change', function webViewerChange(evt) {
   // implemented in Firefox.
   var file = files[0];
   fileReader.readAsBinaryString(file);
-
   document.title = file.name;
 
   // URL does not reflect proper document location - hiding some icons.