/**
 * @author mrdoob / http://mrdoob.com/
 * @author WestLangley / http://github.com/WestLangley
 * @author bhouston / http://exocortex.com
 */

THREE.Euler = function ( x, y, z, order ) {

	this._x = x || 0;
	this._y = y || 0;
	this._z = z || 0;
	this._order = order || THREE.Euler.DefaultOrder;

};

THREE.Euler.RotationOrders = [ 'XYZ', 'YZX', 'ZXY', 'XZY', 'YXZ', 'ZYX' ];

THREE.Euler.DefaultOrder = 'XYZ';

THREE.Euler.prototype = {

	constructor: THREE.Euler,

	_x: 0, _y: 0, _z: 0, _order: THREE.Euler.DefaultOrder,

	get x () {

		return this._x;

	},

	set x ( value ) {

		this._x = value;
		this.onChangeCallback();

	},

	get y () {

		return this._y;

	},

	set y ( value ) {

		this._y = value;
		this.onChangeCallback();

	},

	get z () {

		return this._z;

	},

	set z ( value ) {

		this._z = value;
		this.onChangeCallback();

	},

	get order () {

		return this._order;

	},

	set order ( value ) {

		this._order = value;
		this.onChangeCallback();

	},

	set: function ( x, y, z, order ) {

		this._x = x;
		this._y = y;
		this._z = z;
		this._order = order || this._order;

		this.onChangeCallback();

		return this;

	},

	copy: function ( euler ) {

		this._x = euler._x;
		this._y = euler._y;
		this._z = euler._z;
		this._order = euler._order;

		this.onChangeCallback();

		return this;

	},

	setFromRotationMatrix: function ( m, order, update ) {

		var clamp = THREE.Math.clamp;

		// assumes the upper 3x3 of m is a pure rotation matrix (i.e, unscaled)

		var te = m.elements;
		var m11 = te[ 0 ], m12 = te[ 4 ], m13 = te[ 8 ];
		var m21 = te[ 1 ], m22 = te[ 5 ], m23 = te[ 9 ];
		var m31 = te[ 2 ], m32 = te[ 6 ], m33 = te[ 10 ];

		order = order || this._order;

		if ( order === 'XYZ' ) {

			this._y = Math.asin( clamp( m13, - 1, 1 ) );

			if ( Math.abs( m13 ) < 0.99999 ) {

				this._x = Math.atan2( - m23, m33 );
				this._z = Math.atan2( - m12, m11 );

			} else {

				this._x = Math.atan2( m32, m22 );
				this._z = 0;

			}

		} else if ( order === 'YXZ' ) {

			this._x = Math.asin( - clamp( m23, - 1, 1 ) );

			if ( Math.abs( m23 ) < 0.99999 ) {

				this._y = Math.atan2( m13, m33 );
				this._z = Math.atan2( m21, m22 );

			} else {

				this._y = Math.atan2( - m31, m11 );
				this._z = 0;

			}

		} else if ( order === 'ZXY' ) {

			this._x = Math.asin( clamp( m32, - 1, 1 ) );

			if ( Math.abs( m32 ) < 0.99999 ) {

				this._y = Math.atan2( - m31, m33 );
				this._z = Math.atan2( - m12, m22 );

			} else {

				this._y = 0;
				this._z = Math.atan2( m21, m11 );

			}

		} else if ( order === 'ZYX' ) {

			this._y = Math.asin( - clamp( m31, - 1, 1 ) );

			if ( Math.abs( m31 ) < 0.99999 ) {

				this._x = Math.atan2( m32, m33 );
				this._z = Math.atan2( m21, m11 );

			} else {

				this._x = 0;
				this._z = Math.atan2( - m12, m22 );

			}

		} else if ( order === 'YZX' ) {

			this._z = Math.asin( clamp( m21, - 1, 1 ) );

			if ( Math.abs( m21 ) < 0.99999 ) {

				this._x = Math.atan2( - m23, m22 );
				this._y = Math.atan2( - m31, m11 );

			} else {

				this._x = 0;
				this._y = Math.atan2( m13, m33 );

			}

		} else if ( order === 'XZY' ) {

			this._z = Math.asin( - clamp( m12, - 1, 1 ) );

			if ( Math.abs( m12 ) < 0.99999 ) {

				this._x = Math.atan2( m32, m22 );
				this._y = Math.atan2( m13, m11 );

			} else {

				this._x = Math.atan2( - m23, m33 );
				this._y = 0;

			}

		} else {

			THREE.warn( 'THREE.Euler: .setFromRotationMatrix() given unsupported order: ' + order )

		}

		this._order = order;

		if ( update !== false ) this.onChangeCallback();

		return this;

	},

	setFromQuaternion: function () {

		var matrix;

		return function ( q, order, update ) {

			if ( matrix === undefined ) matrix = new THREE.Matrix4();
			matrix.makeRotationFromQuaternion( q );
			this.setFromRotationMatrix( matrix, order, update );

			return this;

		};

	}(),

	setFromVector3: function ( v, order ) {

		return this.set( v.x, v.y, v.z, order || this._order );

	},

	reorder: function () {

		// WARNING: this discards revolution information -bhouston

		var q = new THREE.Quaternion();

		return function ( newOrder ) {

			q.setFromEuler( this );
			this.setFromQuaternion( q, newOrder );

		};

	}(),

	equals: function ( euler ) {

		return ( euler._x === this._x ) && ( euler._y === this._y ) && ( euler._z === this._z ) && ( euler._order === this._order );

	},

	fromArray: function ( array ) {

		this._x = array[ 0 ];
		this._y = array[ 1 ];
		this._z = array[ 2 ];
		if ( array[ 3 ] !== undefined ) this._order = array[ 3 ];

		this.onChangeCallback();

		return this;

	},

	toArray: function ( array, offset ) {

		if ( array === undefined ) array = [];
		if ( offset === undefined ) offset = 0;

		array[ offset ] = this._x;
		array[ offset + 1 ] = this._y;
		array[ offset + 2 ] = this._z;
		array[ offset + 3 ] = this._order;

		return array;
	},

	toVector3: function ( optionalResult ) {

		if ( optionalResult ) {

			return optionalResult.set( this._x, this._y, this._z );

		} else {

			return new THREE.Vector3( this._x, this._y, this._z );

		}

	},

	onChange: function ( callback ) {

		this.onChangeCallback = callback;

		return this;

	},

	onChangeCallback: function () {},

	clone: function () {

		return new THREE.Euler( this._x, this._y, this._z, this._order );

	}

};