/**
 * Runtime Entity
 * @param apiEntity GameLib.D3.API.Entity
 * @constructor
 */
GameLib.Entity = function (
    apiEntity
) {
    if (GameLib.Utils.UndefinedOrNull(apiEntity)) {
        apiEntity = {};
    }

	GameLib.API.Entity.call(
        this,
        apiEntity.id,
        apiEntity.name,
        apiEntity.components,
        apiEntity.parentEntity
    );

    GameLib.Component.call(
        this,
        {
            'components' : [GameLib.Component]
        }
    );
};

GameLib.Entity.prototype = Object.create(GameLib.Component.prototype);
GameLib.Entity.prototype.constructor = GameLib.Entity;

/**
 * Creates an entity instance
 */
GameLib.Entity.prototype.createInstance = function() {
    /**
     * FUCK ecsjs and tiny-ecs - no client-side support and shitty code (only takes constructors as args)
     */
    this.instance = true;
    GameLib.Component.prototype.createInstance.call(this);
};

/**
 * Adds a component to this entity through the instance (should notify the entity manager instance)
 * @param component
 */
GameLib.Entity.prototype.addComponent = function(component) {



    // if (component instanceof GameLib.D3.Mesh) {
    //
    //     /**
    //      * For meshes, simply get the children components
    //      * @type {Array}
    //      */
    //     component.getChildrenComponents().map(function(childComponent){
    //         GameLib.Utils.PushUnique(this.components, childComponent);
    //         childComponent.parentEntity = this;
    //     }.bind(this))
    //
    // } else {

    if (component instanceof GameLib.Component) {

        /**
         * Here we will dig into this component - find all its 'parentEntity' members - and update them accordingly
         */
        component.buildIdToObject();

        /**
         * Also add the child components of this component as components of this entity
         */
        Object.keys(component.idToObject).map(
            function(componentId) {
                GameLib.Utils.PushUnique(this.components, component.idToObject[componentId]);
                component.idToObject[componentId].parentEntity = this;
            }.bind(this)
        );

        GameLib.Utils.PushUnique(this.components, component);
    }
    // }


	/**
     * Finally, we are the boss component - update my parent entity
	 * @type {GameLib.Entity}
	 */
	component.parentEntity = this;

};

/**
 * Returns all components of type 'constructor'
 * @param constructor
 */
GameLib.Entity.prototype.getComponents = function(constructor) {

    var components = this.components.reduce(
        function(result, component) {
            if (component instanceof constructor) {
                result.push(component);
            }
			return result;
        },
        []
    );

    return components;
};

/**
 * Returns the first component or null
 * @param constructor
 */
GameLib.Entity.prototype.getFirstComponent = function(constructor) {

    var components = this.getComponents(constructor);

    if (components.length > 0) {
        return components[0];
    }

    return null;
};

/**
 * Returns true when this entity has a certain component, false otherwise
 * @param constructor
 */
GameLib.Entity.prototype.hasComponent = function(constructor) {

    var has = this.components.reduce(
        function(result, component) {
            if (component instanceof constructor) {
                result = true;
            }
            return result;
        },
        false
    );

    return has;
};

/**
 *
 * @param component
 */
GameLib.Entity.prototype.removeComponent = function(component) {

	if (GameLib.Utils.UndefinedOrNull(component)) {
		component = this.activeComponent;
	}

    var childIndex = this.components.indexOf(component);
    if (childIndex !== -1) {
        this.components.splice(childIndex, 1);
    } else {
        console.error('component not found');
    }

    /**
     * Break the dependency to the parent
     */
    component.parentEntity = null;

    return true;
};

/**
 * Updates an entity instance
 */
GameLib.Entity.prototype.updateInstance = function() {
    console.log('entity update instance called');
};

/**
 * Converts a GameLib.Entity to GameLib.API.Entity
 * @returns {GameLib.API.Entity}
 */
GameLib.Entity.prototype.toApiObject = function() {

    var apiComponents = this.components.map(
        function(component) {
            return GameLib.Utils.IdOrNull(component);
        }
    );

    return new GameLib.API.Entity(
        this.id,
        this.name,
        apiComponents,
        GameLib.Utils.IdOrNull(this.parentEntity)
    );

};

/**
 * Entity from Object
 * @param objectEntity Object
 * @returns {GameLib.Entity}
 * @constructor
 */
GameLib.Entity.FromObject = function(objectEntity) {

    var apiEntity = GameLib.API.Entity.FromObject(objectEntity);

    var entity = new GameLib.Entity(
        apiEntity
    );

    GameLib.EntityManager.Instance.addEntity(entity);

    return entity;
};