mirror of
https://github.com/pdf2htmlEX/pdf2htmlEX.git
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889 lines
26 KiB
JavaScript
889 lines
26 KiB
JavaScript
/* vim: set shiftwidth=2 tabstop=2 autoindent cindent expandtab filetype=javascript : */
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/**
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* @license pdf2htmlEX.js: Core UI functions for pdf2htmlEX
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* Copyright 2012,2013 Lu Wang <coolwanglu@gmail.com> and other contributors
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* https://github.com/coolwanglu/pdf2htmlEX/blob/master/share/LICENSE
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*/
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/*
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* Attention:
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* This files is to be optimized by closure-compiler,
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* so pay attention to the forms of property names:
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*
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* string/bracket form is safe, won't be optimized:
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* var obj={ 'a':'b' }; obj['a'] = 'b';
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* name/dot form will be optimized, the name is likely to be modified:
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* var obj={ a:'b' }; obj.a = 'b';
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*
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* Either form can be used for internal objects,
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* but must be consistent for each one respectively.
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*
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* string/bracket form must be used for external objects
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* e.g. DEFAULT_CONFIG, object stored in page-data
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* property names are part of the `protocol` in these cases.
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*
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*/
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'use strict';
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var pdf2htmlEX = window['pdf2htmlEX'] = window['pdf2htmlEX'] || {};
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/**
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* @const
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* @struct
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*/
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var CSS_CLASS_NAMES = {
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page_frame : '@CSS_PAGE_FRAME_CN@',
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page_content_box : '@CSS_PAGE_CONTENT_BOX_CN@',
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page_data : '@CSS_PAGE_DATA_CN@',
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background_image : '@CSS_BACKGROUND_IMAGE_CN@',
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link : '@CSS_LINK_CN@',
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__dummy__ : 'no comma'
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};
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/**
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* configurations of Viewer
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* @const
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* @dict
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*/
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var DEFAULT_CONFIG = {
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// id of the element to put the pages in
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'container_id' : 'page-container',
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// id of the element for sidebar (to open and close)
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'sidebar_id' : 'sidebar',
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// id of the element for outline
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'outline_id' : 'outline',
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// class for the loading indicator
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'loading_indicator_cls' : 'loading-indicator',
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// How many page shall we preload that are below the last visible page
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'preload_pages' : 3,
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// how many ms should we wait before actually rendering the pages and after a scroll event
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'render_timeout' : 100,
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// zoom ratio step for each zoom in/out event
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'scale_step' : 0.9,
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// register global key handler
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'key_handler' : true,
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// register hashchange handler
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'hashchange_handler' : true,
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'__dummy__' : 'no comma'
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};
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/** @const */
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var EPS = 1e-6;
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/************************************/
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/* utility function */
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/**
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* @param{Array.<number>} ctm
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*/
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function invert(ctm) {
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var det = ctm[0] * ctm[3] - ctm[1] * ctm[2];
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return [ ctm[3] / det
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,-ctm[1] / det
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,-ctm[2] / det
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,ctm[0] / det
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,(ctm[2] * ctm[5] - ctm[3] * ctm[4]) / det
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,(ctm[1] * ctm[4] - ctm[0] * ctm[5]) / det
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];
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};
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/**
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* @param{Array.<number>} ctm
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* @param{Array.<number>} pos
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*/
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function transform(ctm, pos) {
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return [ctm[0] * pos[0] + ctm[2] * pos[1] + ctm[4]
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,ctm[1] * pos[0] + ctm[3] * pos[1] + ctm[5]];
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};
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/**
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* @param{Element} ele
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*/
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function get_page_number(ele) {
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return parseInt(ele.getAttribute('data-page-no'), 16);
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};
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/**
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* @param{NodeList} eles
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*/
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function disable_dragstart(eles) {
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for (var i = 0, l = eles.length; i < l; ++i) {
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eles[i].addEventListener('dragstart', function() {
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return false;
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}, false);
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}
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};
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/**
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* @param{...Object} var_args
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*/
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function clone_and_extend_objs(var_args) {
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var result_obj = {};
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for (var i = 0, l = arguments.length; i < l; ++i) {
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var cur_obj = arguments[i];
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for (var k in cur_obj) {
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if (cur_obj.hasOwnProperty(k)) {
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result_obj[k] = cur_obj[k];
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}
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}
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}
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return result_obj;
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};
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/**
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* @constructor
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* @param{Element} page The element for the page
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*/
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function Page(page) {
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if (!page) return;
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this.loaded = false;
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this.shown = false;
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this.page = page; // page frame element
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this.num = get_page_number(page);
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// page size
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// Need to make rescale work when page_content_box is not loaded, yet
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this.original_height = page.clientHeight;
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this.original_width = page.clientWidth;
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// content box
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var content_box = page.getElementsByClassName(CSS_CLASS_NAMES.page_content_box)[0];
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// if page is loaded
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if (content_box) {
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this.content_box = content_box;
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/*
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* scale ratios
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*
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* original_scale : the first one
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* cur_scale : currently using
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*/
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this.original_scale = this.cur_scale = this.original_height / content_box.clientHeight;
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this.page_data = JSON.parse(page.getElementsByClassName(CSS_CLASS_NAMES.page_data)[0].getAttribute('data-data'));
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this.ctm = this.page_data['ctm'];
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this.ictm = invert(this.ctm);
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this.loaded = true;
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}
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};
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Page.prototype = {
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/* hide & show are for contents, the page frame is still there */
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hide : function(){
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if (this.loaded && this.shown) {
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this.content_box.classList.remove('opened');
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this.shown = false;
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}
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},
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show : function(){
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if (this.loaded && !this.shown) {
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this.content_box.classList.add('opened');
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this.shown = true;
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}
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},
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/**
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* @param{number} ratio
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*/
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rescale : function(ratio) {
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if (ratio === 0) {
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// reset scale
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this.cur_scale = this.original_scale;
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} else {
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this.cur_scale = ratio;
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}
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// scale the content box
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if (this.loaded) {
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var cbs = this.content_box.style;
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cbs.msTransform = cbs.webkitTransform = cbs.transform = 'scale('+this.cur_scale.toFixed(3)+')';
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}
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// stretch the page frame to hold the place
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{
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var ps = this.page.style;
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ps.height = (this.original_height * this.cur_scale) + 'px';
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ps.width = (this.original_width * this.cur_scale) + 'px';
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}
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},
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/*
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* return the coordinate of the top-left corner of container
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* in our coordinate system
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* assuming that p.parentNode === p.offsetParent
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*/
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view_position : function () {
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var p = this.page;
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var c = p.parentNode;
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return [c.scrollLeft - p.offsetLeft - p.clientLeft
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,c.scrollTop - p.offsetTop - p.clientTop];
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},
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height : function () {
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return this.page.clientHeight;
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},
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width : function () {
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return this.page.clientWidth;
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}
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};
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/**
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* @constructor
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* @param{Object=} config
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*/
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function Viewer(config) {
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this.config = clone_and_extend_objs(DEFAULT_CONFIG, (arguments.length > 0 ? config : {}));
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this.pages_loading = [];
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this.init_before_loading_content();
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var self = this;
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document.addEventListener('DOMContentLoaded', function(){
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self.init_after_loading_content();
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}, false);
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};
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Viewer.prototype = {
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scale : 1,
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/*
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* index of the active page (the one with largest visible area)
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* which estimates the page currently being viewed
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*/
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cur_page_idx : 0,
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/*
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* index of the first visible page
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* used when determining current view
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*/
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first_page_idx : 0,
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init_before_loading_content : function() {
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/* hide all pages before loading, will reveal only visible ones later */
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this.pre_hide_pages();
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},
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init_after_loading_content : function() {
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this.sidebar = document.getElementById(this.config['sidebar_id']);
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this.outline = document.getElementById(this.config['outline_id']);
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this.container = document.getElementById(this.config['container_id']);
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this.loading_indicator = document.getElementsByClassName(this.config['loading_indicator_cls'])[0];
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{
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// Open the outline if nonempty
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var empty = true;
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var nodes = this.outline.childNodes;
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for (var i = 0, l = nodes.length; i < l; ++i) {
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var cur_node = nodes[i];
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if (cur_node.nodeName === 'UL') {
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empty = false;
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break;
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}
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}
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if (!empty)
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this.sidebar.classList.add('opened');
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}
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this.find_pages();
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// do nothing if there's nothing
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if(this.pages.length == 0) return;
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// disable dragging of background images
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disable_dragstart(document.getElementsByClassName(CSS_CLASS_NAMES.background_image));
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if (this.config['key_handler'])
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this.register_key_handler();
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var self = this;
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if (this.config['hashchange_handler']) {
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window.addEventListener('hashchange', function(e) {
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self.navigate_to_dest(document.location.hash.substring(1));
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}, false);
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}
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// register schedule rendering
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// renew old schedules since scroll() may be called frequently
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this.container.addEventListener('scroll', function() {
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self.update_page_idx();
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self.schedule_render(true);
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}, false);
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// handle links
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[this.container, this.outline].forEach(function(ele) {
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ele.addEventListener('click', self.link_handler.bind(self), false);
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});
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this.render();
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},
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/*
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* set up this.pages and this.page_map
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* pages is an array holding all the Page objects
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* page-Map maps an original page number (in PDF) to the corresponding index in page
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*/
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find_pages : function() {
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var new_pages = [];
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var new_page_map = {};
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var nodes = this.container.childNodes;
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for (var i = 0, l = nodes.length; i < l; ++i) {
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var cur_node = nodes[i];
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if ((cur_node.nodeType === Node.ELEMENT_NODE)
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&& cur_node.classList.contains(CSS_CLASS_NAMES.page_frame)) {
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var p = new Page(cur_node);
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new_pages.push(p);
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new_page_map[p.num] = new_pages.length - 1;
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}
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}
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this.pages = new_pages;
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this.page_map = new_page_map;
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},
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/**
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* @param{number} idx
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* @param{number=} pages_to_preload
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* @param{function(Page)=} callback
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*
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* TODO: remove callback -> promise ?
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*/
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load_page : function(idx, pages_to_preload, callback) {
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var pages = this.pages;
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if (idx >= pages.length)
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return; // Page does not exist
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var cur_page = pages[idx];
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if (cur_page.loaded)
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return; // Page is loaded
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if (this.pages_loading[idx])
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return; // Page is already loading
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var cur_page_ele = cur_page.page;
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var url = cur_page_ele.getAttribute('data-page-url');
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if (url) {
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this.pages_loading[idx] = true; // set semaphore
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// add a copy of the loading indicator
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var new_loading_indicator = this.loading_indicator.cloneNode();
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new_loading_indicator.classList.add('active');
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cur_page_ele.appendChild(new_loading_indicator);
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// load data
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{
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var self = this;
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var _idx = idx;
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var xhr = new XMLHttpRequest();
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xhr.open('GET', url, true);
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xhr.onreadystatechange = function(){
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if (xhr.readyState != 4) return;
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if (xhr.status === 200) {
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// find the page element in the data
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var div = document.createElement('div');
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div.innerHTML = xhr.responseText;
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var new_page = null;
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var nodes = div.childNodes;
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for (var i = 0, l = nodes.length; i < l; ++i) {
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var cur_node = nodes[i];
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if ((cur_node.nodeType === Node.ELEMENT_NODE)
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&& cur_node.classList.contains(CSS_CLASS_NAMES.page_frame)) {
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new_page = cur_node;
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break;
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}
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}
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// replace the old page with loaded data
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// the loading indicator on this page should also be destroyed
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var p = self.pages[_idx];
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self.container.replaceChild(new_page, p.page);
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p = new Page(new_page);
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self.pages[_idx] = p;
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p.hide();
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p.rescale(self.scale);
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// disable background image dragging
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disable_dragstart(new_page.getElementsByClassName(CSS_CLASS_NAMES.background_image));
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self.schedule_render(false);
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if (callback){ callback(p); }
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}
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// Reset loading token
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delete self.pages_loading[_idx];
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};
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xhr.send(null);
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}
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}
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// Concurrent prefetch of the next pages
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if (pages_to_preload === undefined)
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pages_to_preload = this.config['preload_pages'];
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if (--pages_to_preload > 0) {
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var self = this;
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setTimeout(function() {
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self.load_page(idx+1, pages_to_preload);
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},0);
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}
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},
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/*
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* Hide all pages that have no 'opened' class
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* The 'opened' class will be added to visible pages by JavaScript
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* We cannot add this in the default CSS because JavaScript may be disabled
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*/
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pre_hide_pages : function() {
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/* pages might have not been loaded yet, so add a CSS rule */
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var s = '@media screen{.'+CSS_CLASS_NAMES.page_content_box+'{display:none;}}';
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var n = document.createElement('style');
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if (n.styleSheet) {
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n.styleSheet.cssText = s;
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} else {
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n.appendChild(document.createTextNode(s));
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}
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document.head.appendChild(n);
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},
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/*
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* show visible pages and hide invisible pages
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*/
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render : function () {
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var container = this.container;
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/*
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* show the pages that are 'nearly' visible -- it's right above or below the container
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*
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* all the y values are in the all-page element's coordinate system
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*/
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var container_min_y = container.scrollTop;
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var container_height = container.clientHeight;
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var container_max_y = container_min_y + container_height;
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var visible_min_y = container_min_y - container_height;
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var visible_max_y = container_max_y + container_height;
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var cur_page_fully_visible = false;
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var cur_page_idx = this.cur_page_idx;
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var max_visible_page_idx = cur_page_idx;
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var max_visible_ratio = 0.0;
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var pl = this.pages;
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for (var i = 0, l = pl.length; i < l; ++i) {
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var cur_page = pl[i];
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var cur_page_ele = cur_page.page;
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var page_min_y = cur_page_ele.offsetTop + cur_page_ele.clientTop;
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var page_height = cur_page_ele.clientHeight;
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var page_max_y = page_min_y + page_height;
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if ((page_min_y <= visible_max_y) && (page_max_y >= visible_min_y))
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{
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// cur_page is 'nearly' visible, show it or load it
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if (cur_page.loaded) {
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cur_page.show();
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} else {
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this.load_page(i);
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}
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} else {
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cur_page.hide();
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}
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}
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},
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/*
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* update cur_page_idx and first_page_idx
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* normally called upon scrolling
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*/
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update_page_idx: function () {
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var pages = this.pages;
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var pages_len = pages.length;
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// there is no chance that cur_page_idx or first_page_idx is modified
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if (pages_len < 2) return;
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var container = this.container;
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var container_min_y = container.scrollTop;
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var container_max_y = container_min_y + container.clientHeight;
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// binary search for the first page
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// whose bottom border is below the top border of the container
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var first_idx = -1;
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var last_idx = pages_len;
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var rest_len = last_idx - first_idx;
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// TODO: use current first_page_idx as a hint?
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while(rest_len > 1) {
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var idx = first_idx + Math.floor(rest_len / 2);
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var cur_page_ele = pages[idx].page;
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if (cur_page_ele.offsetTop + cur_page_ele.clientTop + cur_page_ele.clientHeight >= container_min_y) {
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last_idx = idx;
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} else {
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first_idx = idx;
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}
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rest_len = last_idx - first_idx;
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}
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/*
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* with malformed settings it is possible that no page is visible, e.g.
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* - the container is to thin, which lies in the margin between two pages
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* - all pages are completely above or below the container
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* but we just assume that they won't happen.
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*/
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this.first_page_idx = last_idx;
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// find the page with largest visible area
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var cur_page_idx = this.cur_page_idx;
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var max_visible_page_idx = cur_page_idx;
|
|
var max_visible_ratio = 0.0;
|
|
|
|
for(var i = last_idx; i < pages_len; ++i) {
|
|
var cur_page_ele = pages[i].page;
|
|
var page_min_y = cur_page_ele.offsetTop + cur_page_ele.clientTop;
|
|
var page_height = cur_page_ele.clientHeight;
|
|
var page_max_y = page_min_y + page_height;
|
|
if (page_min_y > container_max_y) break;
|
|
|
|
// check the visible fraction of the page
|
|
var page_visible_ratio = ( Math.min(container_max_y, page_max_y)
|
|
- Math.max(container_min_y, page_min_y)
|
|
) / page_height;
|
|
|
|
// stay with the current page if it is still fully visible
|
|
if ((i === cur_page_idx) && (Math.abs(page_visible_ratio - 1.0) <= EPS)) {
|
|
max_visible_page_idx = cur_page_idx;
|
|
break;
|
|
}
|
|
|
|
if (page_visible_ratio > max_visible_ratio) {
|
|
max_visible_ratio = page_visible_ratio;
|
|
max_visible_page_idx = i;
|
|
}
|
|
}
|
|
|
|
this.cur_page_idx = max_visible_page_idx;
|
|
},
|
|
|
|
/**
|
|
* @param{boolean} renew renew the existing schedule instead of using the old one
|
|
*/
|
|
schedule_render : function(renew) {
|
|
if (this.render_timer !== undefined) {
|
|
if (!renew) return;
|
|
clearTimeout(this.render_timer);
|
|
}
|
|
|
|
var self = this;
|
|
this.render_timer = setTimeout(function () {
|
|
/*
|
|
* render() may trigger load_page(), which may in turn trigger another render()
|
|
* so delete render_timer first
|
|
*/
|
|
delete self.render_timer;
|
|
self.render();
|
|
}, this.config['render_timeout']);
|
|
},
|
|
|
|
/*
|
|
* Handling key events, zooming, scrolling etc.
|
|
*/
|
|
register_key_handler: function () {
|
|
/*
|
|
* When user try to zoom in/out using ctrl + +/- or mouse wheel
|
|
* handle this and prevent the default behaviours
|
|
*
|
|
* Code credit to PDF.js
|
|
*/
|
|
var self = this;
|
|
// Firefox specific event, so that we can prevent browser from zooming
|
|
window.addEventListener('DOMMouseScroll', function(e) {
|
|
if (e.ctrlKey) {
|
|
e.preventDefault();
|
|
self.rescale(Math.pow(self.config['scale_step'], e.detail), true);
|
|
}
|
|
}, false);
|
|
|
|
window.addEventListener('keydown', function(e) {
|
|
var handled = false;
|
|
/*
|
|
var cmd = (e.ctrlKey ? 1 : 0)
|
|
| (e.altKey ? 2 : 0)
|
|
| (e.shiftKey ? 4 : 0)
|
|
| (e.metaKey ? 8 : 0)
|
|
;
|
|
*/
|
|
var with_ctrl = e.ctrlKey || e.metaKey;
|
|
var with_alt = e.altKey;
|
|
switch (e.keyCode) {
|
|
case 61: // FF/Mac '='
|
|
case 107: // FF '+' and '='
|
|
case 187: // Chrome '+'
|
|
if (with_ctrl){
|
|
self.rescale(1.0 / self.config['scale_step'], true);
|
|
handled = true;
|
|
}
|
|
break;
|
|
case 173: // FF/Mac '-'
|
|
case 109: // FF '-'
|
|
case 189: // Chrome '-'
|
|
if (with_ctrl){
|
|
self.rescale(self.config['scale_step'], true);
|
|
handled = true;
|
|
}
|
|
break;
|
|
case 48: // '0'
|
|
if (with_ctrl){
|
|
self.rescale(0, false);
|
|
handled = true;
|
|
}
|
|
break;
|
|
case 33: // Page UP:
|
|
if (with_alt) { // alt-pageup -> scroll one page up
|
|
self.scroll_to(self.cur_page_idx - 1);
|
|
} else { // pageup -> scroll one screen up
|
|
self.container.scrollTop -= self.container.clientHeight;
|
|
}
|
|
handled = true;
|
|
break;
|
|
case 34: // Page DOWN
|
|
if (with_alt) { // alt-pagedown -> scroll one page down
|
|
self.scroll_to(self.cur_page_idx + 1);
|
|
} else { // pagedown -> scroll one screen down
|
|
self.container.scrollTop += self.container.clientHeight;
|
|
}
|
|
handled = true;
|
|
break;
|
|
case 35: // End
|
|
self.container.scrollTop = self.container.scrollHeight;
|
|
handled = true;
|
|
break;
|
|
case 36: // Home
|
|
self.container.scrollTop = 0;
|
|
handled = true;
|
|
break;
|
|
}
|
|
if (handled) {
|
|
e.preventDefault();
|
|
return;
|
|
}
|
|
}, false);
|
|
},
|
|
|
|
/**
|
|
* @param{number} ratio
|
|
* @param{boolean} is_relative
|
|
* @param{Array.<number>=} preserve_pos preserve the position after rescaling
|
|
*
|
|
* TODO: offsetX/Y is by default the center of container
|
|
* TODO consider scale on offsetX/Y
|
|
*/
|
|
rescale : function (ratio, is_relative, preserve_pos) {
|
|
var old_scale = this.scale;
|
|
var new_scale = old_scale;
|
|
// set new scale
|
|
if (ratio === 0) {
|
|
new_scale = 1;
|
|
is_relative = false;
|
|
} else if (is_relative)
|
|
new_scale *= ratio;
|
|
else
|
|
new_scale = ratio;
|
|
|
|
this.scale = new_scale;
|
|
|
|
if(!preserve_pos)
|
|
preserve_pos = [0,0]
|
|
|
|
// Save offset of the active page
|
|
var active_page = this.pages[this.cur_page_idx];
|
|
|
|
var active_page_ele = active_page.page;
|
|
var prev_offset = [ active_page_ele.offsetLeft, active_page_ele.offsetTop ];
|
|
|
|
// Rescale pages
|
|
var pl = this.pages;
|
|
for (var i = 0, l = pl.length; i < l; ++i)
|
|
pl[i].rescale(new_scale);
|
|
|
|
var container = this.container;
|
|
// Correct container scroll to keep view aligned while zooming
|
|
var correction_top = active_page_ele.offsetTop - prev_offset[1];
|
|
container.scrollTop += correction_top + preserve_pos[1];
|
|
// Take the center of the view as a reference
|
|
var prev_center_x = container.clientWidth / 2 - prev_offset[0];
|
|
// Calculate the difference respect the center of the view after the zooming
|
|
var correction_left = prev_center_x * (new_scale/old_scale - 1) + active_page_ele.offsetLeft - prev_offset[0];
|
|
// Scroll the container accordingly to keep alignment to the initial reference
|
|
container.scrollLeft += correction_left + preserve_pos[0];
|
|
|
|
// some pages' visibility may be toggled, wait for next render()
|
|
// renew old schedules since rescale() may be called frequently
|
|
this.schedule_render(true);
|
|
},
|
|
|
|
fit_width : function () {
|
|
var page_idx = this.cur_page_idx;
|
|
this.rescale(this.container.clientWidth / this.pages[page_idx].width(), false);
|
|
this.scroll_to(page_idx);
|
|
},
|
|
|
|
fit_height : function () {
|
|
var page_idx = this.cur_page_idx;
|
|
this.rescale(this.container.clientHeight / this.pages[page_idx].height(), false);
|
|
this.scroll_to(page_idx);
|
|
},
|
|
/**
|
|
* @param{Node} ele
|
|
*/
|
|
get_containing_page : function(ele) {
|
|
/* get the page obj containing obj */
|
|
while(ele) {
|
|
if ((ele.nodeType === Node.ELEMENT_NODE)
|
|
&& ele.classList.contains(CSS_CLASS_NAMES.page_frame)) {
|
|
/*
|
|
* Get original page number and map it to index of pages
|
|
* TODO: store the index on the dom element
|
|
*/
|
|
var pn = get_page_number(/** @type{Element} */(ele));
|
|
var pm = this.page_map;
|
|
return (pn in pm) ? this.pages[pm[pn]] : null;
|
|
}
|
|
ele = ele.parentNode;
|
|
}
|
|
return null;
|
|
},
|
|
|
|
/**
|
|
* @param{Event} e
|
|
*/
|
|
link_handler : function (e) {
|
|
var target = /** @type{Node} */(e.target);
|
|
var detail_str = /** @type{string} */ (target.getAttribute('data-dest-detail'));
|
|
if (!detail_str) return;
|
|
|
|
this.navigate_to_dest(detail_str, this.get_containing_page(target));
|
|
e.preventDefault();
|
|
},
|
|
|
|
/**
|
|
* @param{string} detail_str may come from user provided hashtag, need sanitzing
|
|
* @param{Page=} src_page page containing the source event (e.g. link)
|
|
*/
|
|
navigate_to_dest : function(detail_str, src_page) {
|
|
try {
|
|
var detail = JSON.parse(detail_str);
|
|
} catch(e) {
|
|
return;
|
|
}
|
|
|
|
if(!(detail instanceof Array)) return;
|
|
|
|
var target_page_no = detail[0];
|
|
var page_map = this.page_map;
|
|
if (!(target_page_no in page_map)) return;
|
|
var target_page_idx = page_map[target_page_no];
|
|
var target_page = this.pages[target_page_idx];
|
|
|
|
for (var i = 2, l = detail.length; i < l; ++i) {
|
|
var d = detail[i];
|
|
if(!((d === null) || (typeof d === 'number')))
|
|
return;
|
|
}
|
|
|
|
while(detail.length < 6)
|
|
detail.push(null);
|
|
|
|
// cur_page might be undefined, e.g. from Outline
|
|
var cur_page = src_page || this.pages[this.cur_page_idx];
|
|
|
|
var cur_pos = cur_page.view_position();
|
|
cur_pos = transform(cur_page.ictm, [cur_pos[0], cur_page.height()-cur_pos[1]]);
|
|
|
|
var zoom = this.scale;
|
|
var pos = [0,0];
|
|
var upside_down = true;
|
|
var ok = false;
|
|
|
|
// position specified in `detail` are in the raw coordinate system of the page (unscaled)
|
|
var scale = this.scale;
|
|
// TODO: fitb*
|
|
// TODO: BBox
|
|
switch(detail[1]) {
|
|
case 'XYZ':
|
|
pos = [ (detail[2] === null) ? cur_pos[0] : detail[2] * scale
|
|
, (detail[3] === null) ? cur_pos[1] : detail[3] * scale ];
|
|
zoom = detail[4];
|
|
if ((zoom === null) || (zoom === 0))
|
|
zoom = this.scale;
|
|
ok = true;
|
|
break;
|
|
case 'Fit':
|
|
case 'FitB':
|
|
pos = [0,0];
|
|
ok = true;
|
|
break;
|
|
case 'FitH':
|
|
case 'FitBH':
|
|
pos = [0, (detail[2] === null) ? cur_pos[1] : detail[2] * scale];
|
|
ok = true;
|
|
break;
|
|
case 'FitV':
|
|
case 'FitBV':
|
|
pos = [(detail[2] === null) ? cur_pos[0] : detail[2] * scale, 0];
|
|
ok = true;
|
|
break;
|
|
case 'FitR':
|
|
/* locate the top-left corner of the rectangle */
|
|
// TODO
|
|
pos = [detail[2] * scale, detail[5] * scale];
|
|
upside_down = false;
|
|
ok = true;
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
|
|
if (!ok) return;
|
|
|
|
this.rescale(zoom, false);
|
|
|
|
|
|
var self = this;
|
|
/**
|
|
* page should of type Page
|
|
* @param{Page} page
|
|
*/
|
|
var transform_and_scroll = function(page) {
|
|
pos = transform(page.ctm, pos);
|
|
if (upside_down) {
|
|
pos[1] = page.height() - pos[1];
|
|
}
|
|
self.scroll_to(target_page_idx, pos);
|
|
};
|
|
|
|
if (target_page.loaded) {
|
|
transform_and_scroll(target_page);
|
|
} else {
|
|
// TODO: scroll_to may finish before load_page
|
|
|
|
// Scroll to the exact position once loaded.
|
|
this.load_page(target_page_idx, undefined, transform_and_scroll);
|
|
|
|
// In the meantime page gets loaded, scroll approximately position for maximum responsiveness.
|
|
this.scroll_to(target_page_idx);
|
|
}
|
|
},
|
|
|
|
/**
|
|
* @param{number} page_idx
|
|
* @param{Array.<number>=} pos [x,y] where (0,0) is the top-left corner
|
|
*/
|
|
scroll_to : function(page_idx, pos) {
|
|
var pl = this.pages;
|
|
if ((page_idx < 0) || (page_idx >= pl.length)) return;
|
|
var target_page = pl[page_idx];
|
|
var cur_target_pos = target_page.view_position();
|
|
|
|
if (pos === undefined)
|
|
pos = [0,0];
|
|
|
|
var container = this.container;
|
|
container.scrollLeft += pos[0] - cur_target_pos[0];
|
|
container.scrollTop += pos[1] - cur_target_pos[1];
|
|
}
|
|
};
|
|
|
|
// export pdf2htmlEX.Viewer
|
|
pdf2htmlEX['Viewer'] = Viewer;
|