fileviewer/external/ViewerJS/ui_utils.js
2015-06-13 14:19:02 +02:00

395 lines
12 KiB
JavaScript

/* -*- Mode: Java; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* Copyright 2012 Mozilla Foundation
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
'use strict';
var CSS_UNITS = 96.0 / 72.0;
var DEFAULT_SCALE = 'auto';
var UNKNOWN_SCALE = 0;
var MAX_AUTO_SCALE = 1.25;
var SCROLLBAR_PADDING = 40;
var VERTICAL_PADDING = 5;
// optimised CSS custom property getter/setter
var CustomStyle = (function CustomStyleClosure() {
// As noted on: http://www.zachstronaut.com/posts/2009/02/17/
// animate-css-transforms-firefox-webkit.html
// in some versions of IE9 it is critical that ms appear in this list
// before Moz
var prefixes = ['ms', 'Moz', 'Webkit', 'O'];
var _cache = {};
function CustomStyle() {}
CustomStyle.getProp = function get(propName, element) {
// check cache only when no element is given
if (arguments.length === 1 && typeof _cache[propName] === 'string') {
return _cache[propName];
}
element = element || document.documentElement;
var style = element.style, prefixed, uPropName;
// test standard property first
if (typeof style[propName] === 'string') {
return (_cache[propName] = propName);
}
// capitalize
uPropName = propName.charAt(0).toUpperCase() + propName.slice(1);
// test vendor specific properties
for (var i = 0, l = prefixes.length; i < l; i++) {
prefixed = prefixes[i] + uPropName;
if (typeof style[prefixed] === 'string') {
return (_cache[propName] = prefixed);
}
}
//if all fails then set to undefined
return (_cache[propName] = 'undefined');
};
CustomStyle.setProp = function set(propName, element, str) {
var prop = this.getProp(propName);
if (prop !== 'undefined') {
element.style[prop] = str;
}
};
return CustomStyle;
})();
function getFileName(url) {
var anchor = url.indexOf('#');
var query = url.indexOf('?');
var end = Math.min(
anchor > 0 ? anchor : url.length,
query > 0 ? query : url.length);
return url.substring(url.lastIndexOf('/', end) + 1, end);
}
/**
* Returns scale factor for the canvas. It makes sense for the HiDPI displays.
* @return {Object} The object with horizontal (sx) and vertical (sy)
scales. The scaled property is set to false if scaling is
not required, true otherwise.
*/
function getOutputScale(ctx) {
var devicePixelRatio = window.devicePixelRatio || 1;
var backingStoreRatio = ctx.webkitBackingStorePixelRatio ||
ctx.mozBackingStorePixelRatio ||
ctx.msBackingStorePixelRatio ||
ctx.oBackingStorePixelRatio ||
ctx.backingStorePixelRatio || 1;
var pixelRatio = devicePixelRatio / backingStoreRatio;
return {
sx: pixelRatio,
sy: pixelRatio,
scaled: pixelRatio !== 1
};
}
/**
* Scrolls specified element into view of its parent.
* element {Object} The element to be visible.
* spot {Object} An object with optional top and left properties,
* specifying the offset from the top left edge.
*/
function scrollIntoView(element, spot) {
// Assuming offsetParent is available (it's not available when viewer is in
// hidden iframe or object). We have to scroll: if the offsetParent is not set
// producing the error. See also animationStartedClosure.
var parent = element.offsetParent;
var offsetY = element.offsetTop + element.clientTop;
var offsetX = element.offsetLeft + element.clientLeft;
if (!parent) {
console.error('offsetParent is not set -- cannot scroll');
return;
}
while (parent.clientHeight === parent.scrollHeight) {
if (parent.dataset._scaleY) {
offsetY /= parent.dataset._scaleY;
offsetX /= parent.dataset._scaleX;
}
offsetY += parent.offsetTop;
offsetX += parent.offsetLeft;
parent = parent.offsetParent;
if (!parent) {
return; // no need to scroll
}
}
if (spot) {
if (spot.top !== undefined) {
offsetY += spot.top;
}
if (spot.left !== undefined) {
offsetX += spot.left;
parent.scrollLeft = offsetX;
}
}
parent.scrollTop = offsetY;
}
/**
* Helper function to start monitoring the scroll event and converting them into
* PDF.js friendly one: with scroll debounce and scroll direction.
*/
function watchScroll(viewAreaElement, callback) {
var debounceScroll = function debounceScroll(evt) {
if (rAF) {
return;
}
// schedule an invocation of scroll for next animation frame.
rAF = window.requestAnimationFrame(function viewAreaElementScrolled() {
rAF = null;
var currentY = viewAreaElement.scrollTop;
var lastY = state.lastY;
if (currentY !== lastY) {
state.down = currentY > lastY;
}
state.lastY = currentY;
callback(state);
});
};
var state = {
down: true,
lastY: viewAreaElement.scrollTop,
_eventHandler: debounceScroll
};
var rAF = null;
viewAreaElement.addEventListener('scroll', debounceScroll, true);
return state;
}
/**
* Use binary search to find the index of the first item in a given array which
* passes a given condition. The items are expected to be sorted in the sense
* that if the condition is true for one item in the array, then it is also true
* for all following items.
*
* @returns {Number} Index of the first array element to pass the test,
* or |items.length| if no such element exists.
*/
function binarySearchFirstItem(items, condition) {
var minIndex = 0;
var maxIndex = items.length - 1;
if (items.length === 0 || !condition(items[maxIndex])) {
return items.length;
}
if (condition(items[minIndex])) {
return minIndex;
}
while (minIndex < maxIndex) {
var currentIndex = (minIndex + maxIndex) >> 1;
var currentItem = items[currentIndex];
if (condition(currentItem)) {
maxIndex = currentIndex;
} else {
minIndex = currentIndex + 1;
}
}
return minIndex; /* === maxIndex */
}
/**
* Generic helper to find out what elements are visible within a scroll pane.
*/
function getVisibleElements(scrollEl, views, sortByVisibility) {
var top = scrollEl.scrollTop, bottom = top + scrollEl.clientHeight;
var left = scrollEl.scrollLeft, right = left + scrollEl.clientWidth;
function isElementBottomBelowViewTop(view) {
var element = view.div;
var elementBottom =
element.offsetTop + element.clientTop + element.clientHeight;
return elementBottom > top;
}
var visible = [], view, element;
var currentHeight, viewHeight, hiddenHeight, percentHeight;
var currentWidth, viewWidth;
var firstVisibleElementInd = (views.length === 0) ? 0 :
binarySearchFirstItem(views, isElementBottomBelowViewTop);
for (var i = firstVisibleElementInd, ii = views.length; i < ii; i++) {
view = views[i];
element = view.div;
currentHeight = element.offsetTop + element.clientTop;
viewHeight = element.clientHeight;
if (currentHeight > bottom) {
break;
}
currentWidth = element.offsetLeft + element.clientLeft;
viewWidth = element.clientWidth;
if (currentWidth + viewWidth < left || currentWidth > right) {
continue;
}
hiddenHeight = Math.max(0, top - currentHeight) +
Math.max(0, currentHeight + viewHeight - bottom);
percentHeight = ((viewHeight - hiddenHeight) * 100 / viewHeight) | 0;
visible.push({
id: view.id,
x: currentWidth,
y: currentHeight,
view: view,
percent: percentHeight
});
}
var first = visible[0];
var last = visible[visible.length - 1];
if (sortByVisibility) {
visible.sort(function(a, b) {
var pc = a.percent - b.percent;
if (Math.abs(pc) > 0.001) {
return -pc;
}
return a.id - b.id; // ensure stability
});
}
return {first: first, last: last, views: visible};
}
/**
* Event handler to suppress context menu.
*/
function noContextMenuHandler(e) {
e.preventDefault();
}
/**
* Returns the filename or guessed filename from the url (see issue 3455).
* url {String} The original PDF location.
* @return {String} Guessed PDF file name.
*/
function getPDFFileNameFromURL(url) {
var reURI = /^(?:([^:]+:)?\/\/[^\/]+)?([^?#]*)(\?[^#]*)?(#.*)?$/;
// SCHEME HOST 1.PATH 2.QUERY 3.REF
// Pattern to get last matching NAME.pdf
var reFilename = /[^\/?#=]+\.pdf\b(?!.*\.pdf\b)/i;
var splitURI = reURI.exec(url);
var suggestedFilename = reFilename.exec(splitURI[1]) ||
reFilename.exec(splitURI[2]) ||
reFilename.exec(splitURI[3]);
if (suggestedFilename) {
suggestedFilename = suggestedFilename[0];
if (suggestedFilename.indexOf('%') !== -1) {
// URL-encoded %2Fpath%2Fto%2Ffile.pdf should be file.pdf
try {
suggestedFilename =
reFilename.exec(decodeURIComponent(suggestedFilename))[0];
} catch(e) { // Possible (extremely rare) errors:
// URIError "Malformed URI", e.g. for "%AA.pdf"
// TypeError "null has no properties", e.g. for "%2F.pdf"
}
}
}
return suggestedFilename || 'document.pdf';
}
var ProgressBar = (function ProgressBarClosure() {
function clamp(v, min, max) {
return Math.min(Math.max(v, min), max);
}
function ProgressBar(id, opts) {
this.visible = true;
// Fetch the sub-elements for later.
this.div = document.querySelector(id + ' .progress');
// Get the loading bar element, so it can be resized to fit the viewer.
this.bar = this.div.parentNode;
// Get options, with sensible defaults.
this.height = opts.height || 100;
this.width = opts.width || 100;
this.units = opts.units || '%';
// Initialize heights.
this.div.style.height = this.height + this.units;
this.percent = 0;
}
ProgressBar.prototype = {
updateBar: function ProgressBar_updateBar() {
if (this._indeterminate) {
this.div.classList.add('indeterminate');
this.div.style.width = this.width + this.units;
return;
}
this.div.classList.remove('indeterminate');
var progressSize = this.width * this._percent / 100;
this.div.style.width = progressSize + this.units;
},
get percent() {
return this._percent;
},
set percent(val) {
this._indeterminate = isNaN(val);
this._percent = clamp(val, 0, 100);
this.updateBar();
},
setWidth: function ProgressBar_setWidth(viewer) {
if (viewer) {
var container = viewer.parentNode;
var scrollbarWidth = container.offsetWidth - viewer.offsetWidth;
if (scrollbarWidth > 0) {
this.bar.setAttribute('style', 'width: calc(100% - ' +
scrollbarWidth + 'px);');
}
}
},
hide: function ProgressBar_hide() {
if (!this.visible) {
return;
}
this.visible = false;
this.bar.classList.add('hidden');
document.body.classList.remove('loadingInProgress');
},
show: function ProgressBar_show() {
if (this.visible) {
return;
}
this.visible = true;
document.body.classList.add('loadingInProgress');
this.bar.classList.remove('hidden');
}
};
return ProgressBar;
})();