/**
 * Looks from currentPosition to targetPosition (default up is 0,1,0)
 * @param id
 * @param name
 * @param currentComponent R3.Component
 * @param targetComponent R3.Component
 * @param targetPositionOffset R3.API.Vector3
 * @param rotationSpeed Number
 * @param parentEntity
 * @constructor
 */
R3.D3.API.LookAt = function (
    id,
    name,
    currentComponent,
    targetComponent,
    targetPositionOffset,
    rotationSpeed,
    parentEntity
) {

    if (R3.Utils.UndefinedOrNull(id)) {
        id = R3.Utils.RandomId();
    }
    this.id = id;

    if (R3.Utils.UndefinedOrNull(name)) {
        name = this.constructor.name;
    }
    this.name = name;

    if(R3.Utils.UndefinedOrNull(currentComponent)) {
        currentComponent = null;
    }
    this.currentComponent = currentComponent;

    if(R3.Utils.UndefinedOrNull(targetComponent)) {
        targetComponent = null;
    }
    this.targetComponent = targetComponent;

    if(R3.Utils.UndefinedOrNull(targetPositionOffset)) {
        targetPositionOffset = new R3.API.Vector3(0, 0, 0);
    }
    this.targetPositionOffset = targetPositionOffset;

    if (R3.Utils.UndefinedOrNull(rotationSpeed)) {
        rotationSpeed = 22.0;
    }
    this.rotationSpeed = rotationSpeed;

    this.lookAtMatrix = new R3.API.Matrix4();

    this.up = new R3.API.Vector3(0, 1, 0);

    this.currentRotation = new R3.API.Quaternion();

    this.targetPosition = new R3.API.Vector3();

    if(R3.Utils.UndefinedOrNull(parentEntity)) {
        parentEntity = null;
    }
    this.parentEntity = parentEntity;
};

R3.D3.API.LookAt.prototype = Object.create(R3.Component.prototype);
R3.D3.API.LookAt.prototype.constructor = R3.D3.API.LookAt;

/**
 * Object to R3.D3.API.LookAt
 * @param objectComponent
 * @returns {R3.D3.API.LookAt}
 * @constructor
 */
R3.D3.API.LookAt.FromObject = function(objectComponent) {
    return new R3.D3.API.LookAt(
        objectComponent.id,
        objectComponent.name,
        objectComponent.currentComponent,
        objectComponent.targetComponent,
        R3.API.Vector3.FromObject(objectComponent.targetPositionOffset),
        objectComponent.rotationSpeed,
        objectComponent.parentEntity
    );
};