pdf.js/multi-page-viewer.js

401 lines
13 KiB
JavaScript

/* -*- Mode: Java; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- /
/* vim: set shiftwidth=4 tabstop=8 autoindent cindent expandtab: */
"use strict";
var PDFViewer = {
queryParams: {},
element: null,
previousPageButton: null,
nextPageButton: null,
pageNumberInput: null,
scaleInput: null,
willJumpToPage: false,
pdf: null,
url: 'compressed.tracemonkey-pldi-09.pdf',
pageNumber: 1,
numberOfPages: 1,
scale: 1.0,
pageWidth: function() {
return 816 * PDFViewer.scale;
},
pageHeight: function() {
return 1056 * PDFViewer.scale;
},
lastPagesDrawn: [],
visiblePages: function() {
var pageHeight = PDFViewer.pageHeight() + 20; // Add 20 for the margins.
var windowTop = window.pageYOffset;
var windowBottom = window.pageYOffset + window.innerHeight;
var pageStartIndex = Math.floor(windowTop / pageHeight);
var pageStopIndex = Math.ceil(windowBottom / pageHeight);
var pages = [];
for (var i = pageStartIndex; i <= pageStopIndex; i++) {
pages.push(i + 1);
}
return pages;
},
createPage: function(num) {
var anchor = document.createElement('a');
anchor.name = '' + num;
var div = document.createElement('div');
div.id = 'pageContainer' + num;
div.className = 'page';
div.style.width = PDFViewer.pageWidth() + 'px';
div.style.height = PDFViewer.pageHeight() + 'px';
PDFViewer.element.appendChild(anchor);
PDFViewer.element.appendChild(div);
},
removePage: function(num) {
var div = document.getElementById('pageContainer' + num);
if (div && div.hasChildNodes()) {
while (div.childNodes.length > 0) {
div.removeChild(div.firstChild);
}
}
},
drawPage: function(num) {
if (PDFViewer.pdf) {
var page = PDFViewer.pdf.getPage(num);
var div = document.getElementById('pageContainer' + num);
if (div && !div.hasChildNodes()) {
var canvas = document.createElement('canvas');
canvas.id = 'page' + num;
canvas.mozOpaque = true;
// Canvas dimensions must be specified in CSS pixels. CSS pixels
// are always 96 dpi. These dimensions are 8.5in x 11in at 96dpi.
canvas.width = PDFViewer.pageWidth();
canvas.height = PDFViewer.pageHeight();
var ctx = canvas.getContext('2d');
ctx.save();
ctx.fillStyle = 'rgb(255, 255, 255)';
ctx.fillRect(0, 0, canvas.width, canvas.height);
ctx.restore();
var gfx = new CanvasGraphics(ctx);
var fonts = [];
// page.compile will collect all fonts for us, once we have loaded them
// we can trigger the actual page rendering with page.display
page.compile(gfx, fonts);
var fontsReady = true;
// Inspect fonts and translate the missing one
var fontCount = fonts.length;
for (var i = 0; i < fontCount; i++) {
var font = fonts[i];
if (Fonts[font.name]) {
fontsReady = fontsReady && !Fonts[font.name].loading;
continue;
}
new Font(font.name, font.file, font.properties);
fontsReady = false;
}
var pageInterval;
var delayLoadFont = function() {
for (var i = 0; i < fontCount; i++) {
if (Fonts[font.name].loading) {
return;
}
}
clearInterval(pageInterval);
PDFViewer.drawPage(num);
}
if (!fontsReady) {
pageInterval = setInterval(delayLoadFont, 10);
return;
}
page.display(gfx);
div.appendChild(canvas);
}
}
},
changeScale: function(num) {
while (PDFViewer.element.childNodes.length > 0) {
PDFViewer.element.removeChild(PDFViewer.element.firstChild);
}
PDFViewer.scale = num / 100;
if (PDFViewer.pdf) {
for (var i = 1; i <= PDFViewer.numberOfPages; i++) {
PDFViewer.createPage(i);
}
if (PDFViewer.numberOfPages > 0) {
PDFViewer.drawPage(1);
}
}
PDFViewer.scaleInput.value = Math.floor(PDFViewer.scale * 100) + '%';
},
goToPage: function(num) {
if (1 <= num && num <= PDFViewer.numberOfPages) {
PDFViewer.pageNumber = num;
PDFViewer.pageNumberInput.value = PDFViewer.pageNumber;
PDFViewer.willJumpToPage = true;
document.location.hash = PDFViewer.pageNumber;
PDFViewer.previousPageButton.className = (PDFViewer.pageNumber === 1) ?
'disabled' : '';
PDFViewer.nextPageButton.className = (PDFViewer.pageNumber === PDFViewer.numberOfPages) ?
'disabled' : '';
}
},
goToPreviousPage: function() {
if (PDFViewer.pageNumber > 1) {
PDFViewer.goToPage(--PDFViewer.pageNumber);
}
},
goToNextPage: function() {
if (PDFViewer.pageNumber < PDFViewer.numberOfPages) {
PDFViewer.goToPage(++PDFViewer.pageNumber);
}
},
open: function(url) {
PDFViewer.url = url;
document.title = url;
var req = new XMLHttpRequest();
req.open('GET', url);
req.mozResponseType = req.responseType = 'arraybuffer';
req.expected = (document.URL.indexOf('file:') === 0) ? 0 : 200;
req.onreadystatechange = function() {
if (req.readyState === 4 && req.status === req.expected) {
var data = req.mozResponseArrayBuffer ||
req.mozResponse ||
req.responseArrayBuffer ||
req.response;
PDFViewer.pdf = new PDFDoc(new Stream(data));
PDFViewer.numberOfPages = PDFViewer.pdf.numPages;
document.getElementById('numPages').innerHTML = PDFViewer.numberOfPages.toString();
for (var i = 1; i <= PDFViewer.numberOfPages; i++) {
PDFViewer.createPage(i);
}
if (PDFViewer.numberOfPages > 0) {
PDFViewer.drawPage(1);
}
}
};
req.send(null);
}
};
window.onload = function() {
// Parse the URL query parameters into a cached object.
PDFViewer.queryParams = function() {
var qs = window.location.search.substring(1);
var kvs = qs.split('&');
var params = {};
for (var i = 0; i < kvs.length; ++i) {
var kv = kvs[i].split('=');
params[unescape(kv[0])] = unescape(kv[1]);
}
return params;
}();
PDFViewer.element = document.getElementById('viewer');
PDFViewer.pageNumberInput = document.getElementById('pageNumber');
PDFViewer.pageNumberInput.onkeydown = function(evt) {
var charCode = evt.charCode || evt.keyCode;
// Up arrow key.
if (charCode === 38) {
PDFViewer.goToNextPage();
this.select();
}
// Down arrow key.
else if (charCode === 40) {
PDFViewer.goToPreviousPage();
this.select();
}
// All other non-numeric keys (excluding Left arrow, Right arrow,
// Backspace, and Delete keys).
else if ((charCode < 48 || charCode > 57) &&
charCode !== 8 && // Backspace
charCode !== 46 && // Delete
charCode !== 37 && // Left arrow
charCode !== 39 // Right arrow
) {
return false;
}
return true;
};
PDFViewer.pageNumberInput.onkeyup = function(evt) {
var charCode = evt.charCode || evt.keyCode;
// All numeric keys, Backspace, and Delete.
if ((charCode >= 48 && charCode <= 57) ||
charCode === 8 || // Backspace
charCode === 46 // Delete
) {
PDFViewer.goToPage(this.value);
}
this.focus();
};
PDFViewer.previousPageButton = document.getElementById('previousPageButton');
PDFViewer.previousPageButton.onclick = function(evt) {
if (this.className.indexOf('disabled') === -1) {
PDFViewer.goToPreviousPage();
}
};
PDFViewer.previousPageButton.onmousedown = function(evt) {
if (this.className.indexOf('disabled') === -1) {
this.className = 'down';
}
};
PDFViewer.previousPageButton.onmouseup = function(evt) {
this.className = (this.className.indexOf('disabled') !== -1) ? 'disabled' : '';
};
PDFViewer.previousPageButton.onmouseout = function(evt) {
this.className = (this.className.indexOf('disabled') !== -1) ? 'disabled' : '';
};
PDFViewer.nextPageButton = document.getElementById('nextPageButton');
PDFViewer.nextPageButton.onclick = function(evt) {
if (this.className.indexOf('disabled') === -1) {
PDFViewer.goToNextPage();
}
};
PDFViewer.nextPageButton.onmousedown = function(evt) {
if (this.className.indexOf('disabled') === -1) {
this.className = 'down';
}
};
PDFViewer.nextPageButton.onmouseup = function(evt) {
this.className = (this.className.indexOf('disabled') !== -1) ? 'disabled' : '';
};
PDFViewer.nextPageButton.onmouseout = function(evt) {
this.className = (this.className.indexOf('disabled') !== -1) ? 'disabled' : '';
};
PDFViewer.scaleInput = document.getElementById('scale');
PDFViewer.scaleInput.buttonElement = document.getElementById('scaleComboBoxButton');
PDFViewer.scaleInput.buttonElement.listElement = document.getElementById('scaleComboBoxList');
PDFViewer.scaleInput.onchange = function(evt) {
PDFViewer.changeScale(parseInt(this.value));
};
PDFViewer.scaleInput.buttonElement.onclick = function(evt) {
this.listElement.style.display = (this.listElement.style.display === 'block') ? 'none' : 'block';
};
PDFViewer.scaleInput.buttonElement.onmousedown = function(evt) {
if (this.className.indexOf('disabled') === -1) {
this.className = 'down';
}
};
PDFViewer.scaleInput.buttonElement.onmouseup = function(evt) {
this.className = (this.className.indexOf('disabled') !== -1) ? 'disabled' : '';
};
PDFViewer.scaleInput.buttonElement.onmouseout = function(evt) {
this.className = (this.className.indexOf('disabled') !== -1) ? 'disabled' : '';
};
var listItems = PDFViewer.scaleInput.buttonElement.listElement.getElementsByTagName('LI');
for (var i = 0; i < listItems.length; i++) {
var listItem = listItems[i];
listItem.onclick = function(evt) {
PDFViewer.changeScale(parseInt(this.innerHTML));
PDFViewer.scaleInput.buttonElement.listElement.style.display = 'none';
};
}
PDFViewer.pageNumber = parseInt(PDFViewer.queryParams.page) || PDFViewer.pageNumber;
PDFViewer.scale = parseInt(PDFViewer.scaleInput.value) / 100 || 1.0;
PDFViewer.open(PDFViewer.queryParams.file || PDFViewer.url);
window.onscroll = function(evt) {
var lastPagesDrawn = PDFViewer.lastPagesDrawn;
var visiblePages = PDFViewer.visiblePages();
var pagesToDraw = [];
var pagesToKeep = [];
var pagesToRemove = [];
var i;
// Determine which visible pages were not previously drawn.
for (i = 0; i < visiblePages.length; i++) {
if (lastPagesDrawn.indexOf(visiblePages[i]) === -1) {
pagesToDraw.push(visiblePages[i]);
PDFViewer.drawPage(visiblePages[i]);
} else {
pagesToKeep.push(visiblePages[i]);
}
}
// Determine which previously drawn pages are no longer visible.
for (i = 0; i < lastPagesDrawn.length; i++) {
if (visiblePages.indexOf(lastPagesDrawn[i]) === -1) {
pagesToRemove.push(lastPagesDrawn[i]);
PDFViewer.removePage(lastPagesDrawn[i]);
}
}
PDFViewer.lastPagesDrawn = pagesToDraw.concat(pagesToKeep);
// Update the page number input with the current page number.
if (!PDFViewer.willJumpToPage && visiblePages.length > 0) {
PDFViewer.pageNumber = PDFViewer.pageNumberInput.value = visiblePages[0];
PDFViewer.previousPageButton.className = (PDFViewer.pageNumber === 1) ?
'disabled' : '';
PDFViewer.nextPageButton.className = (PDFViewer.pageNumber === PDFViewer.numberOfPages) ?
'disabled' : '';
} else {
PDFViewer.willJumpToPage = false;
}
};
};