iTunes Playlist -> Ordered Folder Full of WAVs (for burning CDs on another machine)

CD.js

var options = {
	"outputDir": "${HOME}/Downloads",
	"numWorkers": 12,
};

var App = Application.currentApplication();
App.includeStandardAdditions = true;
var Finder = Application("Finder");
var iTunes = Application("iTunes");
var Terminal = Application("Terminal");

(function (options) {
	var failUnlessExists, sanitizeText, trackInfo, quoteArgs;
	var lamePath, afPath, playlist, outputDir, commands, i, tracks, workerNum, track, extension, destination;
	
	failUnlessExists = function (path) {
		if (Finder.exists(Path(path))) {
			return true;
		} else {
			throw "Couldn't find " + path.split('/').pop() + "!";
			return false;
		}
	};
	sanitizeText = function (text) {
		return text.replace(/[^A-Za-z0-9 ]/g, "").replace(/[ ]{2,}/g, " ");
	};
	trackInfo = function  (i, track) {
		var num;
		num = i + 1 + "";
		if (num.length < 3) {
			num = new Array(4 - num.length).join("0") + num;
		}
		
		return {
			num: num,
			artist: sanitizeText(track.artist()),
			title: sanitizeText(track.name()),
			path: track.location().toString().replace(/!/g, "\\!"),
		};
	};
	quoteArgs = function () {
		return "\"" + Array.prototype.slice.call(arguments).join("\" \"") + "\"";
	};
	
	lamePath = "/usr/local/bin/lame";
	failUnlessExists(lamePath);
	afPath = "/usr/bin/afconvert";
	failUnlessExists(afPath);

	playlist = App.displayDialog("Please enter the name of the playlist you would like to prepare for CD:", { withTitle: "Playlist", defaultAnswer: "" }).textReturned;
	outputDir = options.outputDir + "/" + sanitizeText(playlist);
	Terminal.doScript(quoteArgs("mkdir", "-p", outputDir));
	
	commands = [];
	for (i = 0; i < options.numWorkers; i++) { commands.push(""); }

	tracks = iTunes.sources.byName("Library").userPlaylists.byName(playlist).tracks;
	for (i = 0; i < tracks.length; i++) {
		workerNum = i % options.numWorkers;
		track = trackInfo(i, tracks[i]);
		extension = track.path.split(".").pop();
		destination = outputDir + "/" + track.num + " " + track.artist + " - " + track.title + "." + extension;

		commands[workerNum] += quoteArgs("cp", "-f", track.path, destination) + ";";
		if (extension === "mp3") {
			commands[workerNum] += quoteArgs(lamePath, "--decode", destination) + ";";
		} else if (extension === "m4a") {
			commands[workerNum] += quoteArgs(afPath, destination, "--verbose", "--data", "LEI16@44100", "--file", "WAVE", "--quality", "127") + ";";
		}
		if (extension === "mp3" || extension === "m4a") {
			commands[workerNum] += quoteArgs("rm", "-f", destination) + ";";
		}
	}

	for (i = 0; i < commands.length; i++) { Terminal.doScript(commands[i]); }
})(options);