import { System } from '@serpentity/serpentity';

import DrawnGrabberNode from '../nodes/drawn_grabber';

/**
 * Shows a different graphic during the duration of lock
 *
 * @extends {external:Serpentity.System}
 * @class DrawGrabSystem
 * @param {object} config a configuration object to extend.
 */
export default class DrawGrabSystem extends System {

  constructor(config = {}) {

    super();

    /**
     * The node collection of grabbers
     *
     * @property {external:Serpentity.NodeCollection} drawnGrabbers
     * @instance
     * @memberof DrawGrabSystem
     */
    this.drawnGrabbers = null;
  }

  /**
   * Initializes system when added. Requests drawn grabber nodes
   *
   * @function added
   * @memberof DrawGrabSystem
   * @instance
   * @param {external:Serpentity.Engine} engine the serpentity engine to
   * which we are getting added
   */
  added(engine) {

    this.drawnGrabbers = engine.getNodes(DrawnGrabberNode);
  }

  /**
   * Clears system resources when removed.
   *
   * @function removed
   * @instance
   * @memberof DrawGrabSystem
   */
  removed() {

    this.drawnGrabbers = null;
  }

  /**
   * Runs on every update of the loop. Updates image depending on if
   * grab is locked and active
   *
   * @function update
   * @instance
   * @param {Number} currentFrameDuration the duration of the current
   * frame
   * @memberof DrawGrabSystem
   */
  update(currentFrameDuration) {

    for (const drawnGrabber of this.drawnGrabbers) {

      const grab = drawnGrabber.grab;
      const container = drawnGrabber.container.container;

      if (grab.locked && grab.constraint) {
        this._drawGrabFace(container);
        continue;
      }

      if (grab.locked) {
        this._drawGrabCooldownFace(container);
        continue;
      }

      this._removeGrabFace(container);
    }
  }

  // Draws the grab face

  _drawGrabFace(container) {

    const effort = container.getChildByName('effort');
    const shadow = container.getChildByName('shadow');
    effort.visible = true;
    shadow.visible = false;
  }

  // Draws the grab cooldown face

  _drawGrabCooldownFace(container) {

    const effort = container.getChildByName('effort');
    const shadow = container.getChildByName('shadow');
    effort.visible = false;
    shadow.visible = true;
  }

  // Removes the dash face

  _removeGrabFace(container) {

    const effort = container.getChildByName('effort');
    const shadow = container.getChildByName('shadow');
    effort.visible = false;
    shadow.visible = false;
  }
}