// Copyright 2016 Google Inc. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

namespace GoogleVR.VideoDemo {
  using UnityEngine;
  using UnityEngine.EventSystems;
  using UnityEngine.UI;

  public class ScrubberEvents : MonoBehaviour {
    private GameObject newPositionHandle;

    private Vector3[] corners;
    private Slider slider;

    private VideoControlsManager mgr;

    public VideoControlsManager ControlManager {
      set {
        mgr = value;
      }
    }

    void Start() {
      foreach (Image im in GetComponentsInChildren<Image>(true)) {
        if (im.gameObject.name == "newPositionHandle") {
          newPositionHandle = im.gameObject;
          break;
        }
      }

      corners = new Vector3[4];
      GetComponent<Image>().rectTransform.GetWorldCorners(corners);
      slider = GetComponentInParent<Slider>();
    }

    void Update() {
      bool setPos = false;
      if (GvrPointerInputModule.Pointer != null) {
        RaycastResult r = GvrPointerInputModule.Pointer.CurrentRaycastResult;
        if (r.gameObject != null) {
          newPositionHandle.transform.position = new Vector3(
              r.worldPosition.x,
              newPositionHandle.transform.position.y,
              newPositionHandle.transform.position.z);
          setPos = true;
        }
      }
      if (!setPos) {
        newPositionHandle.transform.position = slider.handleRect.transform.position;
      }
    }

    public void OnPointerEnter(BaseEventData data) {
      if (GvrPointerInputModule.Pointer != null) {
        RaycastResult r = GvrPointerInputModule.Pointer.CurrentRaycastResult;
        if (r.gameObject != null) {
          newPositionHandle.transform.position = new Vector3(
              r.worldPosition.x,
              newPositionHandle.transform.position.y,
              newPositionHandle.transform.position.z);
        }
      }
      newPositionHandle.SetActive(true);
    }

    public void OnPointerExit(BaseEventData data) {
      newPositionHandle.SetActive(false);
    }

    public void OnPointerClick(BaseEventData data) {
      float minX = corners[0].x;
      float maxX = corners[3].x;

      float pct = (newPositionHandle.transform.position.x - minX) / (maxX - minX);

      if (mgr != null) {
        long p = (long)(slider.maxValue * pct);
        mgr.Player.CurrentPosition = p;
      }
    }
  }
}