AppExperiments

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

namespace Leap.Unity.Apps.Galaxies {

  public class PanelTransitionController : MonoBehaviour {

    public RectTransform panel;
    public RectTransform outline;

    public float speed = 4f;

    [Header("Animation Curves")]
    public AnimationCurve panelWeightToXScale;
    public AnimationCurve panelWeightToYScale;
    public AnimationCurve panelWeightToZScale;

    private Vector3 _baseLocalScale = Vector3.one;

    private float _curPanelWeight    = 1f;
    private float _curOutlineWeight  = 0f;

    private float _targetPanelWeight   = 1f;
    private float _targetOutlineWeight = 0f;

    public bool isTransitionFinished {
      get {
        return _curPanelWeight == _targetPanelWeight
            && _curOutlineWeight == _targetOutlineWeight;
      }
    }

    protected virtual void Reset() {
      var panelStateController = GetComponent<PanelStateController>();
      if (panelStateController != null) {
        if (panelStateController.transitionController == null) {
          panelStateController.transitionController = this;
        }
      }
    }

    protected virtual void Start() {
      _baseLocalScale = panel.transform.localScale;
    }

    protected virtual void Update() {
      // Linearly move current to target weights, obeying constraints along the way.

      if (_curOutlineWeight < 0.80f) {
        if (_curPanelWeight > _targetPanelWeight) {
          _curPanelWeight -= speed * Time.deltaTime;
          if (_curPanelWeight < _targetPanelWeight) _curPanelWeight = _targetPanelWeight;
        }
        else if (_curPanelWeight < _targetPanelWeight) {
          _curPanelWeight += speed * Time.deltaTime;
          if (_curPanelWeight > _targetPanelWeight) _curPanelWeight = _targetPanelWeight;
        }
      }

      if (_curPanelWeight < 0.80f) {
        if (_curOutlineWeight > _targetOutlineWeight) {
          _curOutlineWeight -= speed * Time.deltaTime;
          if (_curOutlineWeight < _targetOutlineWeight) _curOutlineWeight = _targetOutlineWeight;
        }
        else if (_curOutlineWeight < _targetOutlineWeight) {
          _curOutlineWeight += speed * Time.deltaTime;
          if (_curOutlineWeight > _targetOutlineWeight) _curOutlineWeight = _targetOutlineWeight;
        }
      }

      updateAnimationState();
    }

    private void updateAnimationState() {
      panel.transform.localScale = new Vector3(_baseLocalScale.x * panelWeightToXScale.Evaluate(_curPanelWeight),
                                              _baseLocalScale.y * panelWeightToYScale.Evaluate(_curPanelWeight),
                                              _baseLocalScale.z * panelWeightToZScale.Evaluate(_curPanelWeight));

      outline.transform.localScale = new Vector3(_baseLocalScale.x * panelWeightToXScale.Evaluate(_curOutlineWeight),
                                                _baseLocalScale.y * panelWeightToYScale.Evaluate(_curOutlineWeight),
                                                _baseLocalScale.z * panelWeightToZScale.Evaluate(_curOutlineWeight));
    }

    private void updateActiveState() {
      bool targetPanelState = true;
      bool targetOutlineState = false;

      if (_curOutlineWeight > 0f) {
        targetOutlineState = true;
      }

      if (_curPanelWeight > 0f) {
        targetPanelState = true;
      }

      if (_curOutlineWeight < 0.01f
          && _curPanelWeight < 0.01f) {
        targetPanelState = false;
        targetOutlineState = false;
      }

      panel.gameObject.SetActive(targetPanelState);
      outline.gameObject.SetActive(targetOutlineState);
    }

    public bool UpdateTransitionToOpen() {
      _targetPanelWeight   = 1f;
      _targetOutlineWeight = 0f;

      updateActiveState();

      return isTransitionFinished;
    }

    public bool UpdateTransitionToClosed() {
      _targetPanelWeight   = 0f;
      _targetOutlineWeight = 0f;

      updateActiveState();

      return isTransitionFinished;
    }

    public bool UpdateTransitionToOutline() {
      _targetPanelWeight   = 0f;
      _targetOutlineWeight = 1f;

      updateActiveState();

      return isTransitionFinished;
    }

  }

}