using UnityEditor;
using UnityEngine;
using System;
using System.Linq;
using System.Reflection;

[InitializeOnLoad]
public static class IAPDefineSymbolAdder
{
    private const string SYMBOL_IAP = "UNITY_IAP";
    private const string SYMBOL_PURCHASING = "UNITY_PURCHASING";

    static IAPDefineSymbolAdder()
    {
        CheckAndUpdateSymbols();
    }

    [MenuItem("Tools/IAP/检查并更新宏")]
    public static void CheckAndUpdateSymbols()
    {
        bool iapInstalled = IsIAPInstalled();

        foreach (BuildTargetGroup group in new[] { BuildTargetGroup.Android, BuildTargetGroup.iOS })
        {
            string defines = PlayerSettings.GetScriptingDefineSymbolsForGroup(group);
            var symbols = defines.Split(';').Where(s => !string.IsNullOrEmpty(s)).ToList();

            if (iapInstalled)
            {
                // 需要宏但宏不存在 → 添加
                bool changed = false;
                if (!symbols.Contains(SYMBOL_IAP)) { symbols.Add(SYMBOL_IAP); changed = true; }
                if (!symbols.Contains(SYMBOL_PURCHASING)) { symbols.Add(SYMBOL_PURCHASING); changed = true; }

                if (changed)
                {
                    PlayerSettings.SetScriptingDefineSymbolsForGroup(group, string.Join(";", symbols));
                    Debug.Log($"[IAP] 检测到 IAP 已安装，已为 {group} 添加宏。");
                }
            }
            else
            {
                // 不需要宏但宏存在 → 移除
                bool changed = symbols.Remove(SYMBOL_IAP) || symbols.Remove(SYMBOL_PURCHASING);

                if (changed)
                {
                    PlayerSettings.SetScriptingDefineSymbolsForGroup(group, string.Join(";", symbols));
                    Debug.Log($"[IAP] 检测到 IAP 未安装，已为 {group} 移除宏。");
                }
            }
        }
    }

    private static bool IsIAPInstalled()
    {
        if (TypeExists("UnityEngine.Purchasing.Product"))
            return true;

        var assemblies = AppDomain.CurrentDomain.GetAssemblies();
        if (assemblies.Any(a => a.GetName().Name.Contains("UnityEngine.Purchasing")))
            return true;

        try
        {
            Assembly.Load("UnityEngine.Purchasing");
            return true;
        }
        catch
        {
            return false;
        }
    }

    private static bool TypeExists(string typeName)
    {
        try
        {
            return AppDomain.CurrentDomain.GetAssemblies()
                .SelectMany(assembly =>
                {
                    try { return assembly.GetTypes(); }
                    catch (ReflectionTypeLoadException e) { return e.Types.Where(t => t != null); }
                })
                .Any(t => t.FullName == typeName);
        }
        catch
        {
            return false;
        }
    }
}