// 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 System.Collections;

  public class MenuHandler : MonoBehaviour {
    public GameObject[] menuObjects;

    public void HideMenu() {
      foreach (GameObject m in menuObjects) {
        Renderer r = m.GetComponent<Renderer>();
        if (r != null) {
          r.enabled = false;
        } else {
          m.SetActive(false);
        }
        StartCoroutine(DoFade());
      }
    }

    public void ShowMenu() {
      foreach (GameObject m in menuObjects) {
        Renderer r = m.GetComponent<Renderer>();
        if (r != null) {
          r.enabled = true;
        } else {
          m.SetActive(true);
        }
      }
      StartCoroutine(DoAppear());
    }

    IEnumerator DoAppear() {
      CanvasGroup cg = GetComponent<CanvasGroup>();
      while (cg.alpha < 1.0) {
        cg.alpha += Time.deltaTime * 2;
        yield return null;
      }
      cg.interactable = true;
      yield break;
    }

    IEnumerator DoFade() {
      CanvasGroup cg = GetComponent<CanvasGroup>();
      while (cg.alpha > 0) {
        cg.alpha -= Time.deltaTime;
        yield return null;
      }
      cg.interactable = false;
      yield break;
    }
  }
}