#if UNITY_EDITOR
using System;
using System.Collections.Generic;
using System.IO;
using UnityEditor;
using UnityEngine;

namespace AIGame.EditorTools
{
    /// <summary>Common 标准控件的九宫格导入规则，基于 Doc/UI_Normal_Set.md。</summary>
    public static class UiSpriteNineSliceRules
    {
        private const string CommonRoot = "Assets/Bundles/UI/Texture/Common/";
        // W,H,L,R,T,B：设计尺寸与边界；实际切图按尺寸换算，并包含 2px 透明留边。
        private static readonly Dictionary<string, int[]> Rules = new Dictionary<string, int[]>(StringComparer.OrdinalIgnoreCase)
        {
            { "ui_panel_main", new[] { 480, 256, 40, 40, 40, 40 } },
            { "ui_panel_popup", new[] { 360, 240, 36, 36, 36, 36 } },
            { "ui_panel_content", new[] { 320, 200, 28, 28, 28, 28 } },
            { "ui_panel_header", new[] { 400, 80, 32, 32, 24, 24 } },
            { "btn_primary_normal", new[] { 224, 88, 32, 32, 24, 24 } },
            { "btn_primary_pressed", new[] { 224, 88, 32, 32, 24, 24 } },
            { "btn_primary_disabled", new[] { 224, 88, 32, 32, 24, 24 } },
            { "btn_secondary_normal", new[] { 224, 88, 32, 32, 24, 24 } },
            { "btn_secondary_pressed", new[] { 224, 88, 32, 32, 24, 24 } },
            { "btn_small_normal", new[] { 160, 64, 24, 24, 18, 18 } },
            { "btn_small_pressed", new[] { 160, 64, 24, 24, 18, 18 } },
            { "scrollbar_track_v", new[] { 28, 160, 8, 8, 16, 16 } },
            { "scrollbar_thumb_v", new[] { 28, 80, 8, 8, 16, 16 } },
            { "input_bg_normal", new[] { 360, 72, 28, 28, 20, 20 } },
            { "input_bg_focus", new[] { 360, 72, 28, 28, 20, 20 } },
            { "ui_list_item_normal", new[] { 320, 72, 20, 20, 16, 16 } },
            { "ui_list_item_selected", new[] { 320, 72, 20, 20, 16, 16 } },
            { "tab_active", new[] { 200, 72, 28, 28, 20, 20 } },
            { "tab_inactive", new[] { 200, 72, 28, 28, 20, 20 } },
            { "progress_bg", new[] { 400, 32, 16, 16, 10, 10 } },
            { "progress_fill", new[] { 400, 32, 16, 16, 10, 10 } },
            { "slider_track", new[] { 320, 28, 14, 14, 8, 8 } },
            { "slider_fill", new[] { 320, 28, 14, 14, 8, 8 } },
            { "toast_bg", new[] { 280, 80, 28, 28, 20, 20 } },
            { "toggle_bg_off", new[] { 112, 56, 28, 28, 18, 18 } },
            { "toggle_bg_on", new[] { 112, 56, 28, 28, 18, 18 } }
        };

        public static bool IsStandardControl(string path)
        {
            if (string.IsNullOrEmpty(path)) return false;
            path = path.Replace('\\', '/');
            return path.StartsWith(CommonRoot, StringComparison.OrdinalIgnoreCase)
                && string.Equals(Path.GetDirectoryName(path)?.Replace('\\', '/'), CommonRoot.TrimEnd('/'), StringComparison.OrdinalIgnoreCase)
                && Rules.ContainsKey(Path.GetFileNameWithoutExtension(path));
        }

        public static Vector4 GetBorder(string path, int width, int height)
        {
            int[] rule = Rules[Path.GetFileNameWithoutExtension(path)];
            float sx = Mathf.Max(1, width - 4) / (float)rule[0];
            float sy = Mathf.Max(1, height - 4) / (float)rule[1];
            // Unity Vector4 顺序为 L,B,R,T，与文档 L,R,T,B 不同。
            float maxX = Mathf.Max(1, (width - 1) / 2);
            float maxY = Mathf.Max(1, (height - 1) / 2);
            return new Vector4(
                Mathf.Clamp(Mathf.Round(rule[2] * sx) + 2, 1, maxX),
                Mathf.Clamp(Mathf.Round(rule[5] * sy) + 2, 1, maxY),
                Mathf.Clamp(Mathf.Round(rule[3] * sx) + 2, 1, maxX),
                Mathf.Clamp(Mathf.Round(rule[4] * sy) + 2, 1, maxY));
        }

        public static bool Configure(TextureImporter importer)
        {
            if (!IsStandardControl(importer.assetPath)) return false;
            importer.GetSourceTextureWidthAndHeight(out int width, out int height);
            Vector4 border = GetBorder(importer.assetPath, width, height);
            var settings = new TextureImporterSettings();
            importer.ReadTextureSettings(settings);
            bool changed = importer.textureType != TextureImporterType.Sprite
                || importer.spriteImportMode != SpriteImportMode.Single
                || settings.spriteMeshType != SpriteMeshType.FullRect
                || importer.spriteBorder != border;
            if (!changed) return false;
            importer.textureType = TextureImporterType.Sprite;
            importer.spriteImportMode = SpriteImportMode.Single;
            importer.ReadTextureSettings(settings);
            settings.spriteMeshType = SpriteMeshType.FullRect;
            importer.SetTextureSettings(settings);
            importer.spriteBorder = border;
            return true;
        }

        [MenuItem("Tools/UI/Apply Standard Control Nine-Slice")]
        public static void ApplyFromMenu()
        {
            Debug.Log("[UIGen] 九宫格更新: " + ApplyExisting() + " 张标准控件图。");
        }

        public static int ApplyExisting()
        {
            if (EditorApplication.isPlayingOrWillChangePlaymode)
                throw new InvalidOperationException("Apply UI sprite borders in Edit Mode.");
            int changed = 0;
            foreach (string name in Rules.Keys)
            {
                string path = CommonRoot + name + ".png";
                var importer = AssetImporter.GetAtPath(path) as TextureImporter;
                if (importer == null || !Configure(importer)) continue;
                importer.SaveAndReimport();
                changed++;
            }
            return changed;
        }
    }

    public sealed class UiSpriteNineSlicePostprocessor : AssetPostprocessor
    {
        private void OnPreprocessTexture()
        {
            UiSpriteNineSliceRules.Configure((TextureImporter)assetImporter);
        }
    }
}
#endif