#if UNITY_IOS
using UnityEditor;
using UnityEditor.Callbacks;
using System.IO;
using System.Text;

/// <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。
/// </summary>
public class iOSIconPostProcessor
{
    private const string SOURCE_ICON_DIR = "Assets/Icons/iOS/";

    // 各尺寸图标配置 (idiom, scale, size, 文件名)
    private static readonly (string idiom, string scale, string size, string file)[] ICON_CONFIGS =
    {
        ("iphone", "2x", "20x20",       "icon-20@2x.png"),
        ("iphone", "3x", "20x20",       "icon-20@3x.png"),
        ("iphone", "2x", "29x29",       "icon-29@2x.png"),
        ("iphone", "3x", "29x29",       "icon-29@3x.png"),
        ("iphone", "2x", "40x40",       "icon-40@2x.png"),
        ("iphone", "3x", "40x40",       "icon-40@3x.png"),
        ("iphone", "2x", "60x60",       "icon-60@2x.png"),
        ("iphone", "3x", "60x60",       "icon-60@3x.png"),
        ("ipad",   "2x", "20x20",       "icon-20@2x.png"),
        ("ipad",   "2x", "29x29",       "icon-29@2x.png"),
        ("ipad",   "2x", "40x40",       "icon-40@2x.png"),
        ("ipad",   "2x", "76x76",       "icon-76@2x.png"),
        ("ipad",   "2x", "83.5x83.5",   "icon-83.5@2x.png"),
        ("ios-marketing", "1x", "1024x1024", "icon-1024.png"),
    };

    [PostProcessBuild(int.MaxValue)]
    public static void OnPostProcessBuild(BuildTarget target, string pathToBuiltProject)
    {
        if (target != BuildTarget.iOS) return;

        string iconSetPath = Path.Combine(pathToBuiltProject, "Unity-iPhone/Images.xcassets/AppIcon.appiconset");
        if (!Directory.Exists(iconSetPath))
        {
            UnityEngine.Debug.LogWarning($"[iOSIconPostProcessor] 未找到 AppIcon.appiconset 目录: {iconSetPath}");
            return;
        }

        int copied = 0;
        foreach (var cfg in ICON_CONFIGS)
        {
            string src = Path.GetFullPath(Path.Combine(SOURCE_ICON_DIR, cfg.file));
            string dst = Path.Combine(iconSetPath, cfg.file);
            if (File.Exists(src))
            {
                File.Copy(src, dst, overwrite: true);
                copied++;
            }
            else
            {
                UnityEngine.Debug.LogWarning($"[iOSIconPostProcessor] 缺少图标文件: {src}");
            }
        }

        if (copied > 0)
        {
            WriteContentsJson(iconSetPath);
            UnityEngine.Debug.Log($"[iOSIconPostProcessor] 已替换 {copied} 个 App 图标到 Xcode 项目");
        }
    }

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

        for (int i = 0; i < ICON_CONFIGS.Length; i++)
        {
            var cfg = ICON_CONFIGS[i];
            sb.Append("    {");
            sb.Append($"\"idiom\" : \"{cfg.idiom}\", ");
            sb.Append($"\"scale\" : \"{cfg.scale}\", ");
            sb.Append($"\"size\" : \"{cfg.size}\"");
            if (!string.IsNullOrEmpty(cfg.file))
                sb.Append($", \"filename\" : \"{cfg.file}\"");
            sb.Append("}");
            if (i < ICON_CONFIGS.Length - 1) sb.Append(",");
            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