function disableStyles(doc, disable) {
	for ( var i=0; i<doc.styleSheets.length; i++) {
		void(doc.styleSheets.item(i).disabled=disable);
	}
}

function addStyleSheet() {
	var style = document.createElement("style");
	// WebKit hack :(
	style.appendChild(document.createTextNode(""));
	document.head.appendChild(style);
	return style.sheet;
}

function getCSSRule(sheet, selector, del) {
        lcSelector = selector.toLowerCase();
        for  ( var i=0; i<sheet.cssRules.length; i++) {
		if (sheet.cssRules.item(i).selectorText.toLowerCase() == lcSelector) {
			if (del) {
				sheet.deleteRule(i);
				return null;
			} else {
				return sheet.cssRules.item(i);
			}
		}
	}
	return null;
}

function addCSSRule(sheet, selector, rules, index) {
	if("insertRule" in sheet) {
		sheet.insertRule(selector + "{" + rules + "}", index);
	}
	else if("addRule" in sheet) {
		sheet.addRule(selector, rules, index);
	}
}

function delCSSRule(sheet, selector) {
	getCSSRule(sheet, selector, true);
}

/*function getUrlParameter(name) {
	name = name.replace(/[\[]/, '\\[').replace(/[\]]/, '\\]');
	var regex = new RegExp('[\\?&]' + name + '=([^&#]*)');
	var results = regex.exec(location.search);
	return results === null ? '' : decodeURIComponent(results[1].replace(/\+/g, ' '));
}*/

function getUrlParameter(param){
	var pattern = new RegExp('[?&]'+param+'((=([^&]*))|(?=(&|$)))','i');
	var m = window.location.search.match(pattern);
	return m && ( typeof(m[3])==='undefined' ? '' : m[3] );
}

function renderEpub(file) {
	// only enable close button when launched in an iframe
	if (parent !== window) {
		$('#close').show();
		$('#close').on('click', function() { reader.book.destroy(); parent.OCA.Files_Reader.Plugin.hide(); });
	}

	// some parameters... 
	EPUBJS.filePath = "vendor/epubjs/";
	EPUBJS.cssPath = "css/";

	// touch-enabled devices...
	$('#touch_nav').prop('checked', !('ontouchstart' in document.documentElement));
	if (!($('#touch_nav').prop('checked'))) {
		$("#next").addClass("touch_nav");
		$("#prev").addClass("touch_nav");
	}

	// idevices...
	if (navigator.userAgent.match(/(iPad|iPhone|iPod)/g)) {
		$('head').append($('<link rel="stylesheet" type="text/css" />').attr('href', document.getElementsByTagName("base").item(0).href + 'css/idevice.css'));
	}

	// IE < 11
	if (navigator.userAgent.indexOf("MSIE") != -1) {
		EPUBJS.Hooks.register("beforeChapterDisplay").wgxpath = function(callback, renderer){
			wgxpath.install(renderer.render.window);
			if(callback)
				callback();
		};
		wgxpath.install(window);
	}

	function nightModeConfig() {
		delCSSRule(EPUBJS.nightSheet, EPUBJS.nightSelector);
		addCSSRule(EPUBJS.nightSheet, EPUBJS.nightSelector, 'color: ' + EPUBJS.nightModeColor +  ' !important; background: ' + EPUBJS.nightModeBackground + ' !important;');
	}

	// nightMode
	EPUBJS.nightMode = false;
	EPUBJS.nightSheet = addStyleSheet();
	EPUBJS.nightSelector = '.night *';
	EPUBJS.nightModeBackground = $('#nightModeBackground').val();
	EPUBJS.nightModeColor = $('#nightModeColor').val();
	addCSSRule(EPUBJS.nightSheet, '.nonight', 'background: initial !important;');
	nightModeConfig();

	$('#nightModeBackground').on('change', function() {
		EPUBJS.nightModeBackground = $('#nightModeBackground').val();
		nightModeConfig();
	});

	$('#nightModeColor').on('change', function() {
		EPUBJS.nightModeColor = $('#nightModeColor').val();
		nightModeConfig();
	});

	//var reader = ePubReader(document.getElementById("dllink").value,  { contained: true });
	var reader = ePubReader(file, { contained: true });

	// enable night/day mode switch by clicking on the book title/author
	// just switching in the "night" class works on some browsers but not on others, hence the trickery with
	// setStyle/removeStyle...
	$('#metainfo').on('click', function() {
		if(EPUBJS.nightMode) {
			reader.book.removeStyle("background");
			reader.book.removeStyle("color");
			$("#outerContainer").removeClass("night");
			EPUBJS.nightMode = false;
		} else {
			reader.book.setStyle("background", EPUBJS.nightModeBackground);
			reader.book.setStyle("color", EPUBJS.nightModeColor);
			$("#outerContainer").addClass("night");
			EPUBJS.nightMode = true;
		}
	});

	// extra-wide page turn area?
	$('#touch_nav').on('click', function() {
		if ($('#touch_nav').prop('checked')) {
			$("#prev").removeClass("touch_nav");
			$("#next").removeClass("touch_nav");
		} else {
			$("#prev").addClass("touch_nav");
			$("#next").addClass("touch_nav");
		}
	});
		
	// user-defined font
	EPUBJS.ignore_css = false;
	EPUBJS.bookFrame = null;
	EPUBJS.user_fontFamily = $('#fontFamily').val();
	EPUBJS.user_fontSize = $('#fontSize').val() + '%';

	$('#ignore_css').on('click', function() {
		EPUBJS.bookFrame = document.getElementsByTagName('iframe')[0].contentDocument;
		if ($('#ignore_css').prop('checked')) {
			$('#fontFamily').prop('disabled',false);
			$('#fontSize').prop('disabled',false);
			EPUBJS.ignore_css = true;
			reader.book.setStyle('font-size', EPUBJS.user_fontSize);
			reader.book.setStyle('font-family', EPUBJS.user_fontFamily);
		} else {
			$('#fontFamily').prop('disabled',true);
			$('#fontSize').prop('disabled',true);
			EPUBJS.ignore_css = false;
			reader.book.removeStyle('font-size');
			reader.book.removeStyle('font-family');
		}
		disableStyles(EPUBJS.bookFrame, EPUBJS.ignore_css);
;
	});

	$('#fontSize').on('change', function() {
		EPUBJS.user_fontSize = $('#fontSize').val() + '%';
		$('#font_example').css('font-size', EPUBJS.user_fontSize);
		reader.book.setStyle('font-size', EPUBJS.user_fontSize);
	});
	$('#fontFamily').on('change', function() {
		EPUBJS.user_fontFamily = $('#fontFamily').val();
		$('#font_example').css('font-family', EPUBJS.user_fontFamily);
		reader.book.setStyle('font-family', EPUBJS.user_fontFamily);
	});
}

function renderCbr(file) {
	CBRJS.filePath = "vendor/cbrjs/";

	var reader = cbReader(file, { contained: true });

	if (parent !== window) {
		$('.close').removeClass('hide');
		$('.close').on('click', function() { parent.OCA.Files_Reader.Plugin.hide(); });
	}

}

document.onreadystatechange = function () {  
	if (document.readyState == "complete") {
		var type=decodeURIComponent(getUrlParameter('type'));
		var file=decodeURIComponent(getUrlParameter('file'));

		switch (type) {
			case 'application/epub+zip':
				renderEpub(file);
				break;
			case 'application/x-cbr':
				renderCbr(file);
				break;
			default:
				console.log(type + ' is not supported by Reader');
		}
	}
};