#if UNITY_IOS
using UnityEditor;
using UnityEditor.Build;
using UnityEditor.Build.Reporting;
using System.IO;
using System.Text;
using System.Collections.Generic;
using UnityEngine;

/// <summary>
/// iOS 出包后自动替换高清 App 图标，解决 Unity 压缩导致图标模糊的问题。
/// 使用 IPostprocessBuildWithReport 确保在所有 PostProcessBuild 之后执行。
/// 使用方式：将精确尺寸的 PNG 图标放入 Assets/Icons/iOS/ 目录下，打包时自动生效。
/// 命名规则：iPhone-App-180.png（设备-用途-像素尺寸）可被 Xcode Asset Catalog 自动识别。
/// </summary>
public class iOSIconPostProcessor : IPostprocessBuildWithReport
{
    public int callbackOrder => int.MaxValue;

    private const string SOURCE_ICON_DIR = "Assets/Icons/iOS/";

    // 图标配置: (idiom, scale, 点尺寸, 源文件名, 目标文件名)
    // 源文件在 Assets/Icons/iOS/ 下，目标文件写入 Xcode 的 AppIcon.appiconset
    private static readonly (string idiom, string scale, string size, string src, string dst)[] ICON_CONFIGS =
    {
        // --- iPhone ---
        ("iphone", "2x", "20x20",   "iPhone-Notification-40.png",  "Icon-iPhone-Notification-40.png"),
        ("iphone", "3x", "20x20",   "iPhone-Notification-60.png",  "Icon-iPhone-Notification-60.png"),
        ("iphone", "2x", "29x29",   "iPhone-Settings-58.png",      "Icon-iPhone-Settings-58.png"),
        ("iphone", "3x", "29x29",   "iPhone-Settings-87.png",      "Icon-iPhone-Settings-87.png"),
        ("iphone", "2x", "40x40",   "iPhone-Spotlight-80.png",     "Icon-iPhone-Spotlight-80.png"),
        ("iphone", "3x", "40x40",   "iPhone-Spotlight-120.png",    "Icon-iPhone-Spotlight-120.png"),
        ("iphone", "2x", "60x60",   "iPhone-App-120.png",          "Icon-iPhone-App-120.png"),
        ("iphone", "3x", "60x60",   "iPhone-App-180.png",          "Icon-iPhone-App-180.png"),

        // --- iPad（复用 iPhone 同名图标作为回退） ---
        ("ipad", "2x", "20x20",     "iPhone-Notification-40.png",  "Icon-iPad-Notification-40.png"),
        ("ipad", "2x", "29x29",     "iPhone-Settings-58.png",      "Icon-iPad-Settings-58.png"),
        ("ipad", "2x", "40x40",     "iPhone-Spotlight-80.png",     "Icon-iPad-Spotlight-80.png"),
        ("ipad", "2x", "76x76",     "iPhone-Spotlight-80.png",     "Icon-iPad-App-76.png"),
        ("ipad", "2x", "83.5x83.5", "iPhone-App-120.png",          "Icon-iPad-Pro-App-167.png"),

        // --- App Store ---
        ("ios-marketing", "1x", "1024x1024", "AppStore-1024.png", "Icon-AppStore-1024.png"),
    };

    public void OnPostprocessBuild(BuildReport report)
    {
        if (report.summary.platform != BuildTarget.iOS) return;

        string pathToBuiltProject = report.summary.outputPath;
        string iconSetPath = FindAppIconPath(pathToBuiltProject);
        if (string.IsNullOrEmpty(iconSetPath))
        {
            Debug.LogWarning($"[iOSIconPostProcessor] 未找到 AppIcon.appiconset 目录，跳过图标替换");
            return;
        }

        EditorApplication.delayCall += () => ReplaceIcons(iconSetPath);
    }

    private static void ReplaceIcons(string iconSetPath)
    {
        if (!Directory.Exists(iconSetPath))
        {
            Debug.LogWarning($"[iOSIconPostProcessor] AppIcon.appiconset 目录已不存在: {iconSetPath}");
            return;
        }

        string projectRoot = Path.GetDirectoryName(Application.dataPath);
        string sourceDir = Path.Combine(projectRoot, SOURCE_ICON_DIR);

        // 清空旧图标
        foreach (string oldFile in Directory.GetFiles(iconSetPath, "*.png"))
        {
            File.Delete(oldFile);
        }
        Debug.Log($"[iOSIconPostProcessor] 已清空旧图标");

        // 复制新图标（源文件 → 目标 Xcode 标准名称）
        var copiedDstFiles = new HashSet<string>();
        foreach (var cfg in ICON_CONFIGS)
        {
            string src = Path.Combine(sourceDir, cfg.src);
            if (File.Exists(src))
            {
                string dst = Path.Combine(iconSetPath, cfg.dst);
                File.Copy(src, dst, overwrite: true);
                copiedDstFiles.Add(cfg.dst);
            }
            else
            {
                Debug.LogWarning($"[iOSIconPostProcessor] 缺少源图标: {cfg.src}");
            }
        }

        if (copiedDstFiles.Count > 0)
        {
            WriteContentsJson(iconSetPath, copiedDstFiles);
            Debug.Log($"[iOSIconPostProcessor] 已替换 {copiedDstFiles.Count} 个 App 图标");
        }
        else
        {
            Debug.LogError("[iOSIconPostProcessor] 未找到任何可用图标");
        }
    }

    private static string FindAppIconPath(string buildPath)
    {
        string[] candidates =
        {
            Path.Combine(buildPath, "Unity-iPhone/Images.xcassets/AppIcon.appiconset"),
            Path.Combine(buildPath, "Images.xcassets/AppIcon.appiconset"),
            Path.Combine(buildPath, "Unity-iPhone/Unity-iPhone/Images.xcassets/AppIcon.appiconset"),
        };

        foreach (string path in candidates)
        {
            if (Directory.Exists(path))
            {
                Debug.Log($"[iOSIconPostProcessor] 找到 AppIcon 目录: {path}");
                return path;
            }
        }

        string searchRoot = Path.Combine(buildPath, "Unity-iPhone");
        if (!Directory.Exists(searchRoot)) searchRoot = buildPath;
        foreach (string dir in Directory.GetDirectories(searchRoot, "AppIcon.appiconset", SearchOption.AllDirectories))
        {
            Debug.Log($"[iOSIconPostProcessor] 搜索找到 AppIcon 目录: {dir}");
            return dir;
        }

        return null;
    }

    private static void WriteContentsJson(string iconSetPath, HashSet<string> dstFiles)
    {
        var sb = new StringBuilder();
        sb.AppendLine("{");
        sb.AppendLine("  \"images\" : [");

        bool first = true;
        foreach (var cfg in ICON_CONFIGS)
        {
            if (!dstFiles.Contains(cfg.dst))
                continue;

            if (!first) sb.AppendLine(",");
            else sb.AppendLine();
            first = false;

            sb.Append($"    {{\"idiom\" : \"{cfg.idiom}\", ");
            sb.Append($"\"scale\" : \"{cfg.scale}\", ");
            sb.Append($"\"size\" : \"{cfg.size}\", ");
            sb.Append($"\"filename\" : \"{cfg.dst}\"}}");
        }

        sb.AppendLine();
        sb.AppendLine("  ],");
        sb.AppendLine("  \"info\" : {");
        sb.AppendLine("    \"version\" : 1,");
        sb.AppendLine("    \"author\" : \"xcode\"");
        sb.AppendLine("  }");
        sb.AppendLine("}");

        string jsonPath = Path.Combine(iconSetPath, "Contents.json");
        File.WriteAllText(jsonPath, sb.ToString());
    }
}
#endif