import Component, { ComponentEvent } from "@egjs/component";
import { vec3, glMatrix, quat } from "gl-matrix";

import FusionPoseSensor from "./input/FusionPoseSensor";

const Y_AXIS_VECTOR = vec3.fromValues(0, 1, 0);

export default class DeviceQuaternion extends Component<{
  change: {
    isTrusted: boolean;
  };
}> {
  private _fusionPoseSensor: FusionPoseSensor | null;
  private _quaternion: quat;

  public constructor() {
    super();

    this._fusionPoseSensor = new FusionPoseSensor();
    this._quaternion = quat.create();

    this._fusionPoseSensor.enable();
    this._fusionPoseSensor.on("change", e => {
      this._quaternion = e.quaternion;

      this.trigger(new ComponentEvent("change", { isTrusted: true }));
    });
  }

  public getCombinedQuaternion(yaw: number) {
    const yawQ = quat.setAxisAngle(quat.create(), Y_AXIS_VECTOR, glMatrix.toRadian(-yaw));
    const conj = quat.conjugate(quat.create(), this._quaternion);
    // Multiply pitch quaternion -> device quaternion -> yaw quaternion
    const outQ = quat.multiply(quat.create(), conj, yawQ);

    return outQ;
  }

  public destroy() {
    // detach all event handler
    this.off();

    if (this._fusionPoseSensor) {
      this._fusionPoseSensor.off();
      this._fusionPoseSensor.destroy();
      this._fusionPoseSensor = null;
    }
  }
}