AppExperiments

using Leap.Unity.Attributes;
using Leap.Unity.Interaction;
using Leap.Unity.Query;
using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;

namespace Leap.Unity.UI {

  public class RadioToggleGroup : MonoBehaviour {

    [EditTimeOnly]
    public List<InteractionToggle> toggles;
    
    private int _activeToggleIdx = 0;
    public int activeToggleIdx { get { return _activeToggleIdx; } }
    public InteractionToggle activeToggle { get { return toggles[activeToggleIdx]; } }

    /// <summary>
    /// Gets whether any of the toggles in the RadioToggleGroup are enabled, or sets
    /// the controlEnabled state for all of the toggles in the group simultaneously.
    /// </summary>
    public bool controlsEnabled {
      get {
        return toggles.Query().Any(t => t.controlEnabled);
      }
      set {
        foreach (var toggle in toggles) {
          toggle.controlEnabled = value;
        }
      }
    }

    public void UntoggleAll() {
      foreach (var toggle in toggles) {
        toggle.Untoggle();
      }
    }

    public Action<int> OnIndexToggled = (idx) => { };

    void Awake() {
      for (int i = 0; i < toggles.Count; i++) {
        var toggle = toggles[i];

        int toggleIndex = i;
        toggle.OnToggle += () => {
          toggle.controlEnabled = false;
          onIndexToggled(toggleIndex);
        };

        for (int j = 0; j < toggles.Count; j++) {
          if (j == i) continue;

          var otherToggle = toggles[j];
          toggle.OnToggle += () => {
            otherToggle.controlEnabled = true;
            otherToggle.isToggled = false;
          };
        }
      }
    }

    private bool _sawWasToggled = false;
    private bool _wasToggled = false;

    public bool wasToggled {
      get { return _wasToggled && _sawWasToggled; }
    }

    private void Update() {
      // This guarantees that "wasToggled" will return true for a full Update cycle of
      // the RadioToggleGroup, regardless of when or how many onIndexToggled callbacks
      // there are. (It may also introduce a frame of latency, but that's fine.)
      if (_wasToggled && !_sawWasToggled) {
        _sawWasToggled = true;
      }
      else if (_sawWasToggled) {
        _wasToggled = false;
        _sawWasToggled = false;
      }
    }

    private void onIndexToggled(int idx) {
      _activeToggleIdx = idx;
      _wasToggled = true;

      OnIndexToggled(idx);
    }

  }

}