module-navigation-tool/Editor/Favorites/Utilities/FavoritesGUIUtility.cs

using UnityEditor;
using UnityEditorInternal;
using UnityEngine;

namespace Game.NavigationTool.Editor.Favorite
{
    internal static class FavoritesGUIUtility
    {
        private static readonly int ENTRY_HASH = "DrawFavoriteEntry".GetHashCode();
        
        public static Favorites.Entry manipulatingEntry;
        public static EManipulatingState manipulatingState;
        public static Vector2 manipulatingMouseOffset;
        public static Rect manipulatingRect;
        
        public static Favorites.Entry hoverEntry;

        public static void DrawEntry(Rect rect, Favorites.Entry entry, Styles styles, bool ignoreIndentLevel = false)
        {
            int id = GUIUtility.GetControlID(ENTRY_HASH, FocusType.Passive, rect);
            bool on = manipulatingEntry == entry;
            bool intersects = rect.Contains(Event.current.mousePosition);

            if (intersects)
                hoverEntry = entry;

            switch (Event.current.type)
            {
                case EventType.MouseDown:
                    if (intersects)
                    {
                        SetManipulating(rect, entry, Event.current.button == 0 ? EManipulatingState.BeginClick : EManipulatingState.BeginContextClick);
                        manipulatingMouseOffset = Event.current.mousePosition - rect.position;
                        Event.current.Use();
                    }
                    break;
                case EventType.MouseUp:
                    if (manipulatingEntry == entry)
                    {
                        if (manipulatingState == EManipulatingState.BeginClick)
                        {
                            if (intersects && Event.current.button == 0)
                                SetManipulating(rect, entry, EManipulatingState.PerformedClick);
                            else
                                SetManipulating(rect, entry, EManipulatingState.EndClick);
                        }
                        else if (manipulatingState == EManipulatingState.BeginContextClick)
                        {
                            if (intersects && Event.current.button == 1)
                                SetManipulating(rect, entry, EManipulatingState.PerformedContextClick);
                            else
                                SetManipulating(rect, entry, EManipulatingState.EndContextClick);
                        }
                        else if (manipulatingState == EManipulatingState.BeginDrag)
                        {
                            if (intersects)
                                SetManipulating(rect, entry, EManipulatingState.EndDrag);
                            else
                                SetManipulating(rect, entry, EManipulatingState.PerformedDrag);
                        }
                        
                        Event.current.Use();
                    }
                    break;
                case EventType.MouseDrag:
                    if (manipulatingEntry == entry)
                    {
                        SetManipulating(rect, entry, EManipulatingState.BeginDrag);
                        Event.current.Use();
                    }
                    break;
                case EventType.Repaint:
                    if (!ignoreIndentLevel)
                    {
                        rect.x += entry.indentLevel * 15.0f;
                        rect.width -= entry.indentLevel * 15.0f;
                    }
                    
                    if (!entry.isAsset)
                        entry.content.image = entry.expanded ? styles.foldoutOut : styles.foldoutIn;
                    
                    Vector2 oldSize = EditorGUIUtility.GetIconSize();
                    EditorGUIUtility.SetIconSize(new Vector2(rect.height, rect.height));
                    GUIStyle style = entry.valid ? styles.entry : styles.invalidEntry;
                    style.Draw(rect, entry.content, id, on, intersects);
                    EditorGUIUtility.SetIconSize(oldSize);
                    break;
            }
        }
        
        public static void DrawShadowEntry(Rect rect, Favorites.Entry entry, Styles styles)
        {
            if (Event.current.type != EventType.Repaint)
                return;

            if (!entry.isAsset)
                entry.content.image = entry.expanded ? styles.foldoutOut : styles.foldoutIn;

            int id = GUIUtility.GetControlID(ENTRY_HASH, FocusType.Passive, rect);
            GUIStyle style = entry.valid ? styles.entry : styles.invalidEntry;

            GUI.enabled = false;
            style.Draw(rect, entry.content, id, false, false);
            GUI.enabled = true;
        }

        public static void EndDraw()
        {
            hoverEntry = null;
        }

        public static Texture2D GetIcon(string path)
        {
            var texture = AssetDatabase.GetCachedIcon(path) as Texture2D;
            
            if (texture == null)
                texture = InternalEditorUtility.GetIconForFile(path);

            return texture;
        }

        public static Texture2D GetFolderIcon()
        {
            return AssetDatabase.GetCachedIcon("Assets") as Texture2D;
        }

        private static void SetManipulating(Rect rect, Favorites.Entry entry, EManipulatingState state)
        {
            manipulatingRect = rect;
            manipulatingEntry = entry;
            manipulatingState = state;
        }
        
        public static void ClearManipulating()
        {
            SetManipulating(Rect.zero, null, EManipulatingState.None);
            hoverEntry = null;
        }
    }
}