/* -*- Mode: Java; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

/* vim: set shiftwidth=2 tabstop=2 autoindent cindent expandtab: */

/* vim modeline copied from pdf.js */

/*

* pdf2htmlEX.js

*

* handles UI events/actions/effects

* Copyright 2012 Lu Wang <coolwanglu@gmail.com>

*/

var pdf2htmlEX = (function(){

var pdf2htmlEX = new Object();

var EPS = 1e-6;

var invert = function(ctm) {

var det = ctm[0] * ctm[3] - ctm[1] * ctm[2];

var ictm = new Array();

ictm[0] = ctm[3] / det;

ictm[1] = -ctm[1] / det;

ictm[2] = -ctm[2] / det;

ictm[3] = ctm[0] / det;

ictm[4] = (ctm[2] * ctm[5] - ctm[3] * ctm[4]) / det;

ictm[5] = (ctm[1] * ctm[4] - ctm[0] * ctm[5]) / det;

return ictm;

};

var transform = function(ctm, pos) {

return [ctm[0] * pos[0] + ctm[2] * pos[1] + ctm[4]

,ctm[1] * pos[0] + ctm[3] * pos[1] + ctm[5]];

};

var Page = function(page, container) {

if(page == undefined) return;

this.p = $(page);

this.n = parseInt(this.p.attr('data-page-no'), 16);

this.b = $('.b', this.p);

/*

* scale ratios

*

* default_r : the first one

* set_r : last set

* cur_r : currently using

*/

this.default_r = this.set_r = this.cur_r = this.p.height() / this.b.height();

this.data = JSON.parse($($('.j', this.p)[0]).attr('data-data'));

this.ctm = this.data.ctm;

this.ictm = invert(this.ctm);

this.container = container;

};

$.extend(Page.prototype, {

hide : function(){

this.b.hide();

},

show : function(){

if(Math.abs(this.set_r - this.cur_r) > EPS) {

this.cur_r = this.set_r;

this.b.css('transform', 'scale('+this.cur_r.toFixed(3)+')');

}

this.b.show();

},

rescale : function(ratio, is_relative) {

if(ratio == 0) {

this.set_r = this.default_r;

} else if (is_relative) {

this.set_r *= ratio;

} else {

this.set_r = ratio;

}

/* wait for redraw */

this.hide();

this.p.height(this.b.height() * this.set_r);

this.p.width(this.b.width() * this.set_r);

},

is_visible : function() {

var off = this.position();

return !((off[1] > this.height()) || (off[1] + this.container.height() < 0));

},

/* return the coordinate of the top-left corner of container

* in our cooridnate system

*/

position : function () {

var off = this.p.offset();

var off_c = this.container.offset();

return [off_c.left-off.left, off_c.top-off.top];

},

height : function() {

return this.p.height();

}

});

pdf2htmlEX.Viewer = function(container_id, outline_id) {

this.container_id = container_id;

this.outline_id = outline_id;

this.init_before_loading_content();

var _ = this;

$(function(){_.init_after_loading_content();});

};

$.extend(pdf2htmlEX.Viewer.prototype, {

/* Constants */

render_timeout : 130,

scale_step : 0.9,

init_before_loading_content : function() {

/*hide all pages before loading, will reveal only visible ones later */

this.pre_hide_pages();

},

init_after_loading_content : function() {

this.outline = $('#'+this.outline_id);

this.container = $('#'+this.container_id);

// need a better design

if(this.outline.children().length > 0) {

this.outline.addClass('opened');

}

var new_pages = new Array();

var pl= $('.p', this.container);

/* don't use for(..in..) */

for(var i = 0, l = pl.length; i < l; ++i) {

var p = new Page(pl[i], this.container);

new_pages[p.n] = p;

}

this.pages = new_pages;

var _ = this;

this.container.scroll(function(){ _.schedule_render(); });

//this.zoom_fixer();

// used by outline/annot_link etc

// note that one is for the class 'a' and the other is for the tag 'a'

this.container.on('click', '.a', this, this.link_handler);

this.outline.on('click', 'a', this, this.link_handler);

this.render();

},

pre_hide_pages : function() {

/* pages might have not been loaded yet, so add a CSS rule */

var s = '.b{display:none;}';

var n = document.createElement('style');

n.type = 'text/css';

if (n.styleSheet) {

n.styleSheet.cssText = s;

} else {

n.appendChild(document.createTextNode(s));

}

document.getElementsByTagName('head')[0].appendChild(n);

},

hide_pages : function() {

var pl = this.pages;

for(var i in pl)

pl[i].hide();

},

render : function () {

/* hide (positional) invisible pages */

var pl = this.pages;

for(var i in pl) {

var p = pl[i];

if(p.is_visible()){

p.show();

} else {

p.hide();

}

}

},

schedule_render : function() {

if(this.render_timer)

clearTimeout(this.render_timer);

var _ = this;

this.render_timer = setTimeout(function () {

_.render();

}, this.render_timeout);

},

zoom_fixer : 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 _ = this;

// Firefox specific event, so that we can prevent browser from zooming

$(window).on('DOMMouseScroll', function(e) {

if (e.ctrlKey) {

e.preventDefault();

_.rescale(Math.pow(_.scale_step, e.detail), true);

}

});

$(window).on('keydown', function keydown(e) {

if (e.ctrlKey || e.metaKey) {

switch (e.keyCode) {

case 61: // FF/Mac '='

case 107: // FF '+' and '='

case 187: // Chrome '+'

_.rescale(1.0 / _.scale_step, true);

break;

case 173: // FF/Mac '-'

case 109: // FF '-'

case 189: // Chrome '-'

_.rescale(_.scale_step, true);

break;

case 48: // '0'

_.rescale(0, false);

break;

default:

return;

}

e.preventDefault();

}

});

},

rescale : function (ratio, is_relative) {

var pl = this.pages;

for(var i in pl) {

pl[i].rescale(ratio, is_relative);

}

this.schedule_render();

},

get_containing_page : function(obj) {

/* get the page obj containing obj */

var p = obj.closest('.p')[0];

return p && this.pages[(new Page(p)).n];

},

link_handler : function (e) {

var _ = e.data;

var t = $(e.currentTarget);

var cur_pos = [0,0];

// cur_page might be undefined, e.g. from Outline

var cur_page = _.get_containing_page(t);

if(cur_page != undefined)

{

cur_pos = cur_page.position();

//get the coordinates in default user system

cur_pos = transform(cur_page.ictm, [cur_pos[0], cur_page.height()-cur_pos[1]]);

}

var detail_str = t.attr('data-dest-detail');

if(detail_str == undefined) return;

var ok = false;

var detail = JSON.parse(detail_str);

var target_page = _.pages[detail[0]];

if(target_page == undefined) return;

var pos = [0,0];

var upside_down = true;

// TODO: zoom

// TODO: BBox

switch(detail[1]) {

case 'XYZ':

pos = [(detail[2] == null) ? cur_pos[0] : detail[2]

,(detail[3] == null) ? cur_pos[1] : detail[3]];

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]]

ok = true;

break;

case 'FitV':

case 'FitBV':

pos = [(detail[2] == null) ? cur_pos[0] : detail[2], 0];

ok = true;

break;

case 'FitR':

/* locate the top-left corner of the rectangle */

pos = [detail[2], detail[5]];

upside_down = false;

ok = true;

break;

default:

ok = false;

break;

}

if(ok) {

pos = transform(target_page.ctm, pos);

if(upside_down) {

pos[1] = target_page.height() - pos[1];

}

_.scroll_to(detail[0], pos);

e.preventDefault();

}

},

/* pos=[x,y], where (0,0) is the top-left corner */

scroll_to : function(pageno, pos) {

var target_page = this.pages[pageno];

if(target_page == undefined) return;

var cur_target_pos = target_page.position();

this.container.scrollLeft(this.container.scrollLeft()-cur_target_pos[0]+pos[0]);

this.container.scrollTop(this.container.scrollTop()-cur_target_pos[1]+pos[1]);

},

__last_member__ : 'no comma' /*,*/

});

return pdf2htmlEX;

})();