//Load Modules
phantom.casperPath = 'C:\\Development\\PhantomJS\\casper';
phantom.injectJs(phantom.casperPath + '\\bin\\bootstrap.js');
var system = require('system');
var casper = require('casper').create({ 
	loadImages: true,
    loadPlugins: true,
    verbose: true,
	clientScripts: ['C:\\Development\\PhantomJS\\jquery.js'],
	viewportSize: {
        width: 1366,
        height: 768,
    },
    pageSettings: {
        javascriptEnabled: true,
		localToRemoteUrlAccessEnabled: true,
        userAgent: 'Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/536.5 (KHTML, like Gecko) Chrome/19.0.1084.56 Safari/536.5',
		XSSAuditingEnabled: false
    }
});

//Check Params
if (system.args.length < 4 || system.args.length > 4) {
    console.log('Usage: downloadimages.js Start_URL Image_Selector NextButton_Selector');
    phantom.exit(1);
}

//Setup 
var i = 0;

//Function to zero pad the image filenames
function pad(number, length) {
    var str = '' + number;
    while (str.length < length) { str = '0' + str; }
    return str;
}

//Load each page
casper.on('load.finished', function(status) {
    this.echo(this.getTitle() + ' (' + this.getCurrentUrl() + ') loaded');
	
	//Attempt to download based on selector (img src)
	var srcurl = this.evaluate(function(selector) {
		return $(selector).attr('src');
	},{selector: system.args[2]});
	if (srcurl == null) {
		this.echo('   No img src found');
		
		//Attempt to download based on selector (background-image)
		var bgurl = this.evaluate(function(selector) {
			return $(selector).css('background-image').replace(/^url|[\(\)]/g, '');
		},{selector: system.args[2]});
		if (bgurl == null || bgurl == 'none') {
			this.echo('   No background-image found');
		}
		else {
			var filename = pad(i,3) + bgurl.substr(bgurl.length - 4);
			this.echo('   Found img src URL: ' + bgurl + ' , downloading as: ' + filename);
			this.download(bgurl, filename);	
			i = i + 1;
		}
	}
	else {
		var filename = pad(i,3) + srcurl.substr(srcurl.length - 4);
		this.echo('   Found img src URL: ' + srcurl + ' , downloading as: ' + filename);
		this.download(srcurl, filename);	
		i = i + 1;
	}
	
	//Attempt to find next button based on selector
	if (this.exists(system.args[3])) {
		this.echo('   Clicking next button (30 second timeout)');
		this.click(system.args[3]);	
		//this.wait(30000);
	}
	else {
		this.echo('   No next button found');
		this.exit();
	};
});

//Load initial page
console.log('Loading - ' + system.args[1]);
casper.start(system.args[1]);

//GO GO GO
casper.run();