// ==UserScript==
// @name        ebjhooker
// @description Grabs image data from the browser viewer to save locally. Still a bit buggy. Currently works when you click off one of the pages. Source has further comments. Updated by Cure (08/13/2017)
// @namespace   ebjhooker
// @include     https://br.ebookjapan.jp/br/reader/viewer/*
// @version     1.2
// @run-at		document-start
// @require     http://ajax.googleapis.com/ajax/libs/jquery/2.1.3/jquery.min.js
// @require     https://raw.githubusercontent.com/eligrey/FileSaver.js/master/FileSaver.js
// ==/UserScript==


// Here's some usage tips
// 1. Get the reader to go in single page mode, it'll make your crop job easier later.
//	1.1. Create a transparency mask in PS, set its treshold to 255, trim transparent pixels, easy cropping done in 5 seconds or less.
// 2. If you pressed cancel at the prompt or if it didn't show at all, press the 'up' key on your keyboard to turn on autoripping
// 3. Autoripping won't stop until it gets to the end or if you make it save the same page twice.
// 4. You can just manually rip using the left arrow key to scroll
// 5. If you want to start ripping at a certain spot, just use any method to get through the book that isn't the left arrow key and it won't rip anything.

var f = HTMLCanvasElement.prototype.toBlob;
var globPress;

this.$ = this.jQuery = jQuery.noConflict(true);
pad = function (n, width, z) {
  z = z || '0';
  n = n + '';
  return n.length >= width ? n : new Array(width - n.length + 1).join(z) + n;
}


 function triggerKey(){
	try{
		var eventObj = document.createEvent("Events");
        eventObj.initEvent("keydown", true, true);
        eventObj.which = 37;
		eventObj.keyCode = 37;
		eventObj.key = "ArrowLeft";
        document.dispatchEvent(eventObj);
	}
	catch(e){
		console.log(e);
	}
 }

// wait for page to load
$(document).ready(function(){
	var pages = [];
	var pagenumber = 0;  //cover has page number 0
	var pagedata = "";
	var interval;
	if(confirm("Dump automatically? (Press the up arrow key to turn it on later, or use the left arrow key to rip manually)")){
		interval = setInterval(triggerKey,4000);
	}
	$(document).keydown(function(e){
	 if(e.keyCode == 37){
		pagecanvas = $(".viewer > canvas:nth-of-type(1)");
		pagenumber = $(".slider__output").text();
		if(pages.includes(pagenumber)){
			console.log("Saving done");
			clearInterval(interval);
		}
		else{
			var tempCanvas = pagecanvas[0];
			tempCanvas.toBlob = f;
			tempCanvas.toBlob(function(blob) {
				var bookName = $('.header__title > h2').text().replace(' ????�???�_', ' ')
				var filename = bookName + pad(parseInt(pagenumber) + 1,4)+'.png';
				saveAs(blob, filename);
				//console.log("saved as "+filename);
			});
			pages.push(pagenumber);
		}
		//super();
	  }else if(e.keyCode == 38){
		  console.log("Manually turning on timer");
		  interval = setInterval(triggerKey,2200);
	  }
	})
});