// ===============================================================================
// HierarchyEnhancer - Quick Toggle for GameObjects
//
// Creator: Scove
// Last Updated: 2024-05-08
// Version: 2.0
//
// Purpose:
// Adds a handy toggle checkbox to the right side of every item in the Hierarchy.
// This allows you to enable or disable GameObjects instantly without selecting them.
//
// Key Features:
// 1. One-click activation/deactivation directly in Hierarchy.
// 2. Full Undo/Redo support integrated with Unity's system.
// 3. Optimized UI placement to avoid overlapping with object names.
// 4. Visual clarity: Helps quickly identify inactive objects in a complex tree.
//
// How to Use:
// 1. Place this script in an 'Editor' folder.
// 2. Look at your Hierarchy window; a small checkbox will appear on the far right.
// 3. Click the checkbox to toggle the Active/Inactive state of any GameObject.
// ===============================================================================

using UnityEditor;
using UnityEngine;

namespace Editor
{
    [InitializeOnLoad]
    public class HierarchyEnhancer
    {
        // Define the width of the toggle area
        private const float TOGGLE_WIDTH = 16f;

        static HierarchyEnhancer()
        {
            // Subscribe to the hierarchy item GUI event
            EditorApplication.hierarchyWindowItemOnGUI += OnHierarchyItemGUI;
        }

        private static void OnHierarchyItemGUI(int instanceID, Rect selectionRect)
        {
            // Get the GameObject associated with this instance ID
            GameObject obj = EditorUtility.EntityIdToObject(instanceID) as GameObject;
            if (obj == null) return;

            // Calculate the position for the Toggle (Aligned to the far right)
            // selectionRect.xMax gives us the right boundary of the Hierarchy row
            Rect toggleRect = new Rect(selectionRect);
            toggleRect.x = selectionRect.xMax - TOGGLE_WIDTH;
            toggleRect.width = TOGGLE_WIDTH;

            // Check current active state
            bool isActive = obj.activeSelf;

            // Handle UI and changes
            EditorGUI.BeginChangeCheck();

            // Set the color based on active state (Optional polish)
            Color originalColor = GUI.color;
            if (!isActive) GUI.color = new Color(1f, 1f, 1f, 0.5f); // Dim the toggle if inactive

            bool newActive = EditorGUI.Toggle(toggleRect, isActive);

            GUI.color = originalColor; // Restore original color for other elements

            if (EditorGUI.EndChangeCheck())
            {
                // Record undo before applying the change
                Undo.RecordObject(obj, "Toggle GameObject Active State");
                obj.SetActive(newActive);
                
                // If it's a Prefab, mark the scene as dirty to ensure it saves
                if (!Application.isPlaying)
                {
                    EditorUtility.SetDirty(obj);
                }
            }
        }
    }
}