/**
 * Runtime color for updating instance objects
 * @param graphics GameLib.D3.Graphics
 * @param parentObject GameLib.D3.*
 * @param apiColor GameLib.API.Color
 * @param grain Number
 * @constructor
 */
GameLib.Color = function (
    graphics,
    apiColor,
    parentObject,
    grain
) {

    this.graphics = graphics;
    this.graphics.isNotThreeThrow();

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

    GameLib.API.Color.call(
        this,
        apiColor.r,
        apiColor.g,
        apiColor.b,
        apiColor.a
    );

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

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

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

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

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

    var instance = null;

    if (update) {
        instance = this.instance;
        instance.r = this.r;
        instance.g = this.g;
        instance.b = this.b;
    } else {
        instance = new THREE.Color(this.r, this.g, this.b);
    }

    return instance;
};

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

    this.createInstance(true);

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

/**
 * Converts runtime color to API Color
 * @returns {GameLib.API.Color}
 */
GameLib.Color.prototype.toApiColor = function() {
    return new GameLib.API.Color(
        this.r,
        this.g,
        this.b,
        this.a
    );
};