/**
 * Runtime quaternion for updating instance objects
 * @param graphics GameLib.D3.Graphics
 * @param parentObject GameLib.D3.*
 * @param apiQuaternion GameLib.API.Quaternion
 * @param grain Number
 * @constructor
 */
GameLib.Quaternion = function (
    graphics,
    apiQuaternion,
    parentObject,
    grain
) {
    this.graphics = graphics;
    this.graphics.isNotThreeThrow();

    if (GameLib.Utils.UndefinedOrNull(apiQuaternion)) {
        apiQuaternion = {};
    }

    GameLib.API.Quaternion.call(
        this,
        apiQuaternion.x,
        apiQuaternion.y,
        apiQuaternion.z,
        apiQuaternion.w,
        apiQuaternion.axis,
        apiQuaternion.angle
    );

    if (GameLib.Utils.UndefinedOrNull(parentObject)) {
        parentObject = null;
    }
    this.parentObject = parentObject;

    this.axis = new GameLib.Vector3(
        this.graphics,
        this.axis,
        this,
        this.grain
    );

    if (GameLib.Utils.UndefinedOrNull(grain)) {
        grain = 0.001;
    }
    this.grain = grain;

    this.instance = this.createInstance();
};

GameLib.Quaternion.prototype = Object.create(GameLib.API.Quaternion.prototype);
GameLib.Quaternion.prototype.constructor = GameLib.Quaternion;

/**
 * Creates an instance quaternion
 * @param update
 * @returns {*}
 */
GameLib.Quaternion.prototype.createInstance = function(update) {

    var instance = null;

    if (update) {
        instance = this.instance;
        instance.x = this.x;
        instance.y = this.y;
        instance.z = this.z;
        instance.w = this.w;
    } else {
        instance = new THREE.Quaternion(
            this.x,
            this.y,
            this.z,
            this.w
        );
    }

    return instance;
};

/**
 * Updates the instance vector, calls updateInstance on the parent object
 */
GameLib.Quaternion.prototype.updateInstance = function() {

    this.createInstance(true);

    if (this.parentObject &&
        this.parentObject.updateInstance) {
        this.parentObject.updateInstance();
    }
};

/**
 * Converts runtime quaternion to API quaternion
 * @returns {*}
 */
GameLib.Quaternion.prototype.toApiQuaternion = function() {
    return new GameLib.API.Quaternion(
        this.x,
        this.y,
        this.z,
        this.w,
        this.axis.toApiVector(),
        this.angle
    );
};