/// Credit dakka
/// Sourced from - http://forum.unity3d.com/threads/scripts-useful-4-6-scripts-collection.264161/#post-1752415
/// Notes - Mod from Yilmaz Kiymaz's editor scripts presentation at Unite 2013

using UnityEngine;
using UnityEditor;
using System.Collections;
using System.Collections.Generic;
using System.Linq;

public class CanvasGroupActivator : EditorWindow {
	
	[MenuItem ("Window/Tools/Canvas Groups Activator")]
	public static void InitWindow()
	{
        EditorWindow.GetWindow<CanvasGroupActivator>();
	}
	
	List<CanvasGroup> canvasGroups;
	
	void OnEnable()
	{
		ObtainCanvasGroups();
	}
	
	void OnFocus()
	{
		ObtainCanvasGroups();
	}

    void ObtainCanvasGroups()
	{
        canvasGroups = new List<CanvasGroup>();
        canvasGroups = GameObject.FindObjectsOfType<CanvasGroup>().ToList();
	}
	
	void OnGUI()
	{
        if (canvasGroups == null)
		{
			return;
		}
		
		GUILayout.Space(10f);
		GUILayout.Label("Canvas Groups");

        for (int i = 0; i < canvasGroups.Count; i++)
		{
            if (canvasGroups[i] == null) { continue; }

            bool initialActive = false;
            if (canvasGroups[i].alpha == 1.0f)
                initialActive = true;

            bool active = EditorGUILayout.Toggle(canvasGroups[i].name, initialActive);
            if (active != initialActive)
			{
				//If deactivated and initially active
				if(!active && initialActive)
				{
					//Deactivate this
                    canvasGroups[i].alpha = 0f;
                    canvasGroups[i].interactable = false;
                    canvasGroups[i].blocksRaycasts = false;
				}
				//If activated and initially deactive
				else if(active && !initialActive)
				{
					//Deactivate all others and activate this
                    HideAllGroups();

                    canvasGroups[i].alpha = 1.0f;
                    canvasGroups[i].interactable = true;
                    canvasGroups[i].blocksRaycasts = true;
				}
			}
		}
		
		GUILayout.Space(5f);
		
		if(GUILayout.Button("Show All"))
		{
            ShowAllGroups();
		}
		
		if(GUILayout.Button ("Hide All"))
		{
            HideAllGroups();
		}
	}

    void ShowAllGroups()
    {
        canvasGroups.ForEach(x =>
        {
            if (x != null)
            {
                x.alpha = 1.0f;
                x.interactable = true;
                x.blocksRaycasts = true;
            }
        });
    }

    void HideAllGroups()
    {
        canvasGroups.ForEach(x =>
        {
            if (x != null)
            {
                x.alpha = 0f;
                x.interactable = false;
                x.blocksRaycasts = false;
            }
        });
    }	
}