var lib_paths = ['/vendor/d3.min.js',
				'/vendor/jquery-3.1.1.min.js',
				'/vendor/Chart.min.js',
				'/vendor/Chart.bundle.min.js']

var fs = require('fs'),
	sys  = require('system'),
	page = require('webpage').create();

if (sys.args.length < 1) { 
	console.log("Missing arguments.");
	phantom.exit(1);
}
else {
	var gem_dir, id, scripts, styles, include_js, options, style;
 
	try {
	    gem_dir    =            sys.args[1];
      scripts    = JSON.parse(sys.args[2]);
     	styles     = JSON.parse(sys.args[3]);
     	include_js = JSON.parse(sys.args[4]);
     	options    = JSON.parse(sys.args[5]);
     	id         = options['id']
	} catch(err) {
		console.log("Error parsing arguments.");
		console.log(sys.args);
		console.log(err)
		page.close();
		phantom.exit(1);
	}

	lib_paths.map(function(path) {
		loadJSfile(gem_dir + path);
	});

	var file_dest = options['file_dest'];
	var file_name = options['file_name'];
	var save      = options['save'];

  style  = "<style>"
	for (i in styles) {
    	style += fs.read(styles[i]);
    }
  style += "</style>"
  
	include_js.forEach(function(d) {phantom.injectJs(d)});
	scripts.forEach(function(d) {loadJSfile(d)});

  try{
    eval(window.onload());
	}
	catch(err){
		console.log(err);
		page.close();
		phantom.exit(1);
	}

  var svg      = new XMLSerializer().serializeToString(d3.select(id).node());  
	page.content = style + svg;

	if(save == "local") {
    if (!fs.changeWorkingDirectory(fs.workingDirectory + file_dest)) {
    	console.log("Unable to access: " + fs.workingDirectory + file_dest);	
			page.close();
			phantom.exit(1);
    }
	}
	else {
		 if (!fs.changeWorkingDirectory(file_dest)) {
    	console.log("Unable to access: " +  file_dest);	
			page.close();
			phantom.exit(1);
    }
	}

	if (page.render(file_name)){
		console.log(file_name + " created!");
	} else {
		console.log("An error occured rendering the image.");
		phantom.exit(1);
	};    	

	page.close();
	phantom.exit(0);
	
};


function loadJSfile(file_path){
	if (!phantom.injectJs(file_path)) {
		console.log('Error loading: ' + file_path);
	}
}	

function readFile(file_path){
	try {fs.read(file_path);}
	catch(err) {
		console.log('Unable to load ' + file_path);
		console.log(err);
		phantom.exit(1);
	}
}