/**
 * @author dmarcos / https://github.com/dmarcos
 * @author mrdoob / http://mrdoob.com
 */

THREE.VRControls = function ( object, callback ) {

	var scope = this;

	// Allow for multiple VR input devices.
	var vrInputs = [];

	var onVRDevices = function ( devices ) {

		for ( var i = 0; i < devices.length; i ++ ) {

			var device = devices[ i ];

			if ( device instanceof PositionSensorVRDevice ) {

				vrInputs.push( devices[ i ] );

			}

		}

		if ( callback !== undefined ) {

			callback( 'HMD not available' );

		}

	};

	if ( navigator.getVRDevices !== undefined ) {

		navigator.getVRDevices().then( onVRDevices );

	} else if ( callback !== undefined ) {

		callback( 'Your browser is not VR Ready' );

	}

	// the Rift SDK returns the position in meters
	// this scale factor allows the user to define how meters
	// are converted to scene units.
	this.scale = 1;

	this.update = function () {

	  for ( var i = 0; i < vrInputs.length; i++ ) {

	    var vrInput = vrInputs[ i ];

	    var state = vrInput.getState();

	    if ( state.orientation !== null ) {

	      object.quaternion.copy( state.orientation );

	    }

	    if ( state.position !== null ) {

	      object.position.copy( state.position ).multiplyScalar( scope.scale );

	    }

	  }

	};

	this.zeroSensor = function () {

	  for ( var i = 0; i < vrInputs.length; i++ ) {

	    var vrInput = vrInputs[ i ];

	    vrInput.zeroSensor();

	  }

	};

};