pdf.js/web/viewer.js
2011-09-03 09:10:24 -05:00

533 lines
16 KiB
JavaScript

/* -*- Mode: Java; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- /
/* vim: set shiftwidth=2 tabstop=2 autoindent cindent expandtab: */
'use strict';
var kDefaultURL = 'compressed.tracemonkey-pldi-09.pdf';
var kDefaultScale = 1.5;
var kDefaultScaleDelta = 1.1;
var kCacheSize = 20;
var kCssUnits = 96.0 / 72.0;
var Cache = function(size) {
var data = [];
this.push = function(view) {
data.push(view);
if (data.length > size)
data.shift().update();
};
};
var cache = new Cache(kCacheSize);
var PDFView = {
pages: [],
thumbnails: [],
currentScale: kDefaultScale,
setScale: function(val, resetAutoSettings) {
var pages = this.pages;
for (var i = 0; i < pages.length; i++)
pages[i].update(val * kCssUnits);
this.currentScale = val;
if (document.location.hash == '#' + this.page)
this.pages[this.page - 1].draw();
else
// Jump the scroll position to the correct page.
document.location.hash = this.page;
var event = document.createEvent('UIEvents');
event.initUIEvent('scalechange', false, false, window, 0);
event.scale = val;
event.resetAutoSettings = resetAutoSettings;
window.dispatchEvent(event);
},
parseScale: function(value) {
var scale = parseFloat(value);
if (scale) {
this.setScale(scale, true);
return;
}
if ('custom' == value)
return;
var currentPage = this.pages[this.page - 1];
var scrollbarPadding = 40;
var pageWidthScale = (window.innerWidth - scrollbarPadding) /
currentPage.width / kCssUnits;
var pageHeightScale = (window.innerHeight - scrollbarPadding) /
currentPage.height / kCssUnits;
if ('page-width' == value)
this.setScale(pageWidthScale);
else if ('page-fit' == value)
this.setScale(Math.min(pageWidthScale, pageHeightScale));
},
zoomIn: function() {
this.setScale(this.currentScale * kDefaultScaleDelta, true);
},
zoomOut: function() {
this.setScale(this.currentScale / kDefaultScaleDelta, true);
},
set page(val) {
var pages = this.pages;
var input = document.getElementById('pageNumber');
if (!(0 < val && val <= pages.length)) {
input.value = this.page;
return;
}
document.location.hash = val;
document.getElementById('previous').disabled = (val == 1);
document.getElementById('next').disabled = (val == pages.length);
if (input.value == val)
return;
input.value = val;
pages[val - 1].draw();
},
get page() {
return parseInt(document.location.hash.substring(1)) || 1;
},
open: function(url, scale) {
if (url.indexOf('http') == 0)
return;
document.title = url;
var xhr = new XMLHttpRequest();
xhr.open('GET', url);
xhr.mozResponseType = xhr.responseType = 'arraybuffer';
xhr.expected = (document.URL.indexOf('file:') === 0) ? 0 : 200;
xhr.onreadystatechange = function() {
if (xhr.readyState === 4 && xhr.status === xhr.expected) {
var data = (xhr.mozResponseArrayBuffer || xhr.mozResponse ||
xhr.responseArrayBuffer || xhr.response);
PDFView.load(data, scale);
}
};
xhr.send(null);
},
navigateTo: function(dest) {
if (typeof dest === 'string')
dest = this.destinations[dest];
if (!(dest instanceof Array))
return; // invalid destination
// dest array looks like that: <page-ref> </XYZ|FitXXX> <args..>
var destRef = dest[0];
var pageNumber = destRef instanceof Object ?
this.pagesRefMap[destRef.num + ' ' + destRef.gen + ' R'] : (destRef + 1);
if (pageNumber) {
this.page = pageNumber;
// TODO scroll to specific region on the page, the precise scaling
// required.
}
},
load: function(data, scale) {
var sidebar = document.getElementById('sidebarView');
sidebar.parentNode.scrollTop = 0;
while (sidebar.hasChildNodes())
sidebar.removeChild(sidebar.lastChild);
clearInterval(sidebar._loadingInterval);
var container = document.getElementById('viewer');
while (container.hasChildNodes())
container.removeChild(container.lastChild);
var pdf = new PDFDoc(new Stream(data));
var pagesCount = pdf.numPages;
document.getElementById('numPages').innerHTML = pagesCount;
var pages = this.pages = [];
var pagesRefMap = {};
var thumbnails = this.thumbnails = [];
for (var i = 1; i <= pagesCount; i++) {
var page = pdf.getPage(i);
pages.push(new PageView(container, page, i, page.width, page.height,
page.stats, this.navigateTo.bind(this)));
thumbnails.push(new ThumbnailView(sidebar, pages[i - 1],
page.width / page.height));
var pageRef = page.ref;
pagesRefMap[pageRef.num + ' ' + pageRef.gen + ' R'] = i;
}
this.setScale(scale || kDefaultScale, true);
this.page = parseInt(document.location.hash.substring(1)) || 1;
this.pagesRefMap = pagesRefMap;
this.destinations = pdf.catalog.destinations;
if (pdf.catalog.documentOutline) {
this.outline = new DocumentOutlineView(pdf.catalog.documentOutline);
var outlineSwitchButton = document.getElementById('outlineSwitch');
outlineSwitchButton.removeAttribute('disabled');
this.switchSidebarView('outline');
}
},
switchSidebarView: function(view) {
var thumbsScrollView = document.getElementById('sidebarScrollView');
var outlineScrollView = document.getElementById('outlineScrollView');
var thumbsSwitchButton = document.getElementById('thumbsSwitch');
var outlineSwitchButton = document.getElementById('outlineSwitch');
switch (view) {
case 'thumbs':
thumbsScrollView.style.display = 'block';
outlineScrollView.style.display = 'none';
thumbsSwitchButton.setAttribute('data-selected', true);
outlineSwitchButton.removeAttribute('data-selected');
break;
case 'outline':
thumbsScrollView.style.display = 'none';
outlineScrollView.style.display = 'block';
thumbsSwitchButton.removeAttribute('data-selected');
outlineSwitchButton.setAttribute('data-selected', true);
break;
}
},
getVisiblePages: function() {
var pages = this.pages;
var kBottomMargin = 10;
var visiblePages = [];
var currentHeight = kBottomMargin;
var windowTop = window.pageYOffset;
for (var i = 1; i <= pages.length; i++) {
var page = pages[i - 1];
var pageHeight = page.height * page.scale + kBottomMargin;
if (currentHeight + pageHeight > windowTop)
break;
currentHeight += pageHeight;
}
var windowBottom = window.pageYOffset + window.innerHeight;
for (; i <= pages.length && currentHeight < windowBottom; i++) {
var page = pages[i - 1];
visiblePages.push({ id: page.id, y: currentHeight, view: page });
currentHeight += page.height * page.scale + kBottomMargin;
}
return visiblePages;
}
};
var PageView = function(container, content, id, width, height,
stats, navigateTo) {
this.width = width;
this.height = height;
this.id = id;
this.content = content;
var anchor = document.createElement('a');
anchor.name = '' + this.id;
var div = document.createElement('div');
div.id = 'pageContainer' + this.id;
div.className = 'page';
container.appendChild(anchor);
container.appendChild(div);
this.update = function(scale) {
this.scale = scale || this.scale;
div.style.width = (this.width * this.scale) + 'px';
div.style.height = (this.height * this.scale) + 'px';
while (div.hasChildNodes())
div.removeChild(div.lastChild);
div.removeAttribute('data-loaded');
};
function setupLinks(canvas, content, scale) {
function bindLink(link, dest) {
link.onclick = function() {
if (dest)
PDFView.navigateTo(dest);
return false;
}
}
var links = content.getLinks();
for (var i = 0; i < links.length; i++) {
var link = document.createElement('a');
link.style.left = Math.floor(links[i].x * scale) + 'px';
link.style.top = Math.floor(links[i].y * scale) + 'px';
link.style.width = Math.ceil(links[i].width * scale) + 'px';
link.style.height = Math.ceil(links[i].height * scale) + 'px';
link.href = links[i].url || '';
bindLink(link, ('dest' in links[i]) ? links[i].dest : null);
div.appendChild(link);
}
}
this.draw = function() {
if (div.hasChildNodes()) {
this.updateStats();
return false;
}
var canvas = document.createElement('canvas');
canvas.id = 'page' + this.id;
canvas.mozOpaque = true;
canvas.width = this.width * this.scale;
canvas.height = this.height * this.scale;
div.appendChild(canvas);
var ctx = canvas.getContext('2d');
ctx.save();
ctx.fillStyle = 'rgb(255, 255, 255)';
ctx.fillRect(0, 0, canvas.width, canvas.height);
ctx.restore();
stats.begin = Date.now();
this.content.startRendering(ctx, this.updateStats);
setupLinks(canvas, this.content, this.scale);
div.setAttribute('data-loaded', true);
return true;
};
this.updateStats = function() {
var t1 = stats.compile, t2 = stats.fonts, t3 = stats.render;
var str = 'Time to compile/fonts/render: ' +
(t1 - stats.begin) + '/' + (t2 - t1) + '/' + (t3 - t2) + ' ms';
document.getElementById('info').innerHTML = str;
};
};
var ThumbnailView = function(container, page, pageRatio) {
var anchor = document.createElement('a');
anchor.href = '#' + page.id;
var div = document.createElement('div');
div.id = 'thumbnailContainer' + page.id;
div.className = 'thumbnail';
anchor.appendChild(div);
container.appendChild(anchor);
this.draw = function() {
if (div.hasChildNodes())
return;
var canvas = document.createElement('canvas');
canvas.id = 'thumbnail' + page.id;
canvas.mozOpaque = true;
var maxThumbSize = 134;
canvas.width = pageRatio >= 1 ? maxThumbSize :
maxThumbSize * pageRatio;
canvas.height = pageRatio <= 1 ? maxThumbSize :
maxThumbSize / pageRatio;
div.setAttribute('data-loaded', true);
div.appendChild(canvas);
var ctx = canvas.getContext('2d');
ctx.save();
ctx.fillStyle = 'rgb(255, 255, 255)';
ctx.fillRect(0, 0, canvas.width, canvas.height);
ctx.restore();
page.content.startRendering(ctx, function() { });
};
};
var DocumentOutlineView = function(outline) {
var outlineView = document.getElementById('outlineView');
function bindItemLink(domObj, item) {
domObj.href = '';
domObj.onclick = function(e) {
PDFView.navigateTo(item.dest);
return false;
};
}
var queue = [{parent: outlineView, items: outline}];
while (queue.length > 0) {
var levelData = queue.shift();
var i, n = levelData.items.length;
for (i = 0; i < n; i++) {
var item = levelData.items[i];
var div = document.createElement('div');
div.className = 'outlineItem';
var a = document.createElement('a');
bindItemLink(a, item);
a.textContent = item.title;
div.appendChild(a);
if (item.items.length > 0) {
var itemsDiv = document.createElement('div');
itemsDiv.className = 'outlineItems';
div.appendChild(itemsDiv);
queue.push({parent: itemsDiv, items: item.items});
}
levelData.parent.appendChild(div);
}
}
};
window.addEventListener('load', function(evt) {
var params = document.location.search.substring(1).split('&');
for (var i = 0; i < params.length; i++) {
var param = params[i].split('=');
params[unescape(param[0])] = unescape(param[1]);
}
PDFView.open(params.file || kDefaultURL, parseFloat(params.scale));
if (!window.File || !window.FileReader || !window.FileList || !window.Blob)
document.getElementById('fileInput').style.display = 'none';
else
document.getElementById('fileInput').value = null;
}, true);
window.addEventListener('pdfloaded', function(evt) {
PDFView.load(evt.detail);
}, true);
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())
cache.push(page.view);
}
if (!visiblePages.length)
return;
var currentId = PDFView.page;
var firstPage = visiblePages[0];
var lastPage = visiblePages[visiblePages.length - 1];
if (currentId > lastPage.id && lastPage.y > window.pageYOffset)
PDFView.page = lastPage.id;
else if (currentId < firstPage.id)
PDFView.page = firstPage.id;
}
window.addEventListener('scroll', function onscroll(evt) {
updateViewarea();
}, true);
window.addEventListener('resize', function onscroll(evt) {
if (document.getElementById('pageWidthOption').selected ||
document.getElementById('pageFitOption').selected)
PDFView.parseScale(document.getElementById('scaleSelect').value);
updateViewarea();
});
window.addEventListener('hashchange', function(evt) {
PDFView.page = PDFView.page;
});
window.addEventListener('change', function(evt) {
var files = evt.target.files;
if (!files || files.length == 0)
return;
// Read the local file into a Uint8Array.
var fileReader = new FileReader();
fileReader.onload = function(evt) {
var data = evt.target.result;
var buffer = new ArrayBuffer(data.length);
var uint8Array = new Uint8Array(buffer);
for (var i = 0; i < data.length; i++)
uint8Array[i] = data.charCodeAt(i);
PDFView.load(uint8Array);
};
// Read as a binary string since "readAsArrayBuffer" is not yet
// implemented in Firefox.
var file = files[0];
fileReader.readAsBinaryString(file);
document.title = file.name;
document.location.hash = 1;
}, true);
window.addEventListener('transitionend', function(evt) {
var pageIndex = 0;
var pagesCount = PDFView.pages.length;
var container = document.getElementById('sidebarView');
container._interval = window.setInterval(function interval() {
if (pageIndex >= pagesCount) {
window.clearInterval(container._interval);
return;
}
PDFView.thumbnails[pageIndex++].draw();
}, 500);
}, true);
window.addEventListener('scalechange', function scalechange(evt) {
var customScaleOption = document.getElementById('customScaleOption');
customScaleOption.selected = false;
if (!evt.resetAutoSettings &&
(document.getElementById('pageWidthOption').selected ||
document.getElementById('pageFitOption').selected)) {
updateViewarea();
return;
}
var options = document.getElementById('scaleSelect').options;
var predefinedValueFound = false;
var value = '' + evt.scale;
for (var i = 0; i < options.length; i++) {
var option = options[i];
if (option.value != evt.scale) {
option.selected = false;
continue;
}
option.selected = true;
predefinedValueFound = true;
}
if (!predefinedValueFound) {
customScaleOption.textContent = Math.round(evt.scale * 10000) / 100 + '%';
customScaleOption.selected = true;
}
updateViewarea();
}, true);
window.addEventListener('pagechange', function pagechange(evt) {
var page = evt.detail;
document.location.hash = page;
document.getElementById('pageNumber').value = page;
document.getElementById('previous').disabled = (page == 1);
document.getElementById('next').disabled = (page == PDFView.pages.length);
}, true);
window.addEventListener('keydown', function (evt) {
switch(evt.keyCode) {
case 61: // '+' and '=' keys
case 107:
case 187:
PDFView.zoomIn();
break;
case 109: // '-' keys
case 189:
PDFView.zoomOut();
break;
}
});