import Tone from "../core/Tone";
import "../signal/Add";
import "../signal/Subtract";
import "../signal/Signal";
import "../component/Split";
import "../core/AudioNode";

/**
 *  @class Mid/Side processing separates the the 'mid' signal
 *         (which comes out of both the left and the right channel)
 *         and the 'side' (which only comes out of the the side channels). <br><br>
 *         <code>
 *         Mid = (Left+Right)/sqrt(2);   // obtain mid-signal from left and right<br>
 *         Side = (Left-Right)/sqrt(2);   // obtain side-signal from left and righ<br>
 *         </code>
 *
 *  @extends {Tone.AudioNode}
 *  @constructor
 */
Tone.MidSideSplit = function(){

	Tone.AudioNode.call(this);
	this.createInsOuts(0, 2);

	/**
	 *  split the incoming signal into left and right channels
	 *  @type  {Tone.Split}
	 *  @private
	 */
	this._split = this.input = new Tone.Split();

	/**
	 *  The mid send. Connect to mid processing. Alias for
	 *  <code>output[0]</code>
	 *  @type {Tone.Add}
	 */
	this._midAdd = new Tone.Add();

	/**
	 * Multiply the _midAdd by sqrt(1/2)
	 * @type {Tone.Multiply}
	 */
	this.mid = this.output[0] = new Tone.Multiply(Math.SQRT1_2);

	/**
	 *  The side output. Connect to side processing. Also Output 1
	 *  @type {Tone.Subtract}
	 */
	this._sideSubtract = new Tone.Subtract();

	/**
	 * Multiply the _midAdd by sqrt(1/2)
	 * @type {Tone.Multiply}
	 */
	this.side = this.output[1] = new Tone.Multiply(Math.SQRT1_2);

	this._split.connect(this._midAdd, 0, 0);
	this._split.connect(this._midAdd, 1, 1);
	this._split.connect(this._sideSubtract, 0, 0);
	this._split.connect(this._sideSubtract, 1, 1);
	this._midAdd.connect(this.mid);
	this._sideSubtract.connect(this.side);
};

Tone.extend(Tone.MidSideSplit, Tone.AudioNode);

/**
 *  clean up
 *  @returns {Tone.MidSideSplit} this
 */
Tone.MidSideSplit.prototype.dispose = function(){
	Tone.AudioNode.prototype.dispose.call(this);
	this.mid.dispose();
	this.mid = null;
	this.side.dispose();
	this.side = null;
	this._midAdd.dispose();
	this._midAdd = null;
	this._sideSubtract.dispose();
	this._sideSubtract = null;
	this._split.dispose();
	this._split = null;
	return this;
};

export default Tone.MidSideSplit;