using System;
using System.Collections.Generic;
using System.IO;
using System.Reflection;
using AlicizaX.Fsm.Runtime;
using AlicizaX.Procedure.Runtime;
using AlicizaX.Runtime;
using HybridCLR;
using UnityEngine;
using YooAsset;

namespace Unity.Startup.Procedure
{
    public sealed class ProcedureLoadAssembly : ProcedureBase
    {
        // private bool m_enableAddressable = true;
        private int m_LoadAssetCount;
        private int m_LoadMetadataAssetCount;
        private int m_FailureAssetCount;
        private int m_FailureMetadataAssetCount;
        private bool m_LoadAssemblyComplete;
        private bool m_LoadMetadataAssemblyComplete;
        private bool m_LoadAssemblyWait;
#pragma warning disable CS0414
        private bool m_LoadMetadataAssemblyWait;
#pragma warning restore CS0414
        private Assembly m_MainLogicAssembly;
        private List<Assembly> m_HotfixAssemblys;

        protected override void OnEnter(IFsm<IProcedureManager> procedureOwner)
        {
            base.OnEnter(procedureOwner);
            Log.Info(" ProcedureLoadAssembly OnEnter");
            m_LoadAssemblyComplete = false;
            m_HotfixAssemblys = new List<Assembly>();

            //AOT Assembly加载原始metadata
            if (AssemblyLoadData.Enable)
            {
#if !UNITY_EDITOR
                m_LoadMetadataAssemblyComplete = false;
                LoadMetadataForAOTAssembly();
#else
                m_LoadMetadataAssemblyComplete = true;
#endif
            }
            else
            {
                m_LoadMetadataAssemblyComplete = true;
            }

            if (!AssemblyLoadData.Enable ||
                GameApp.Resource.GamePlayMode == EPlayMode.EditorSimulateMode)
            {
                m_MainLogicAssembly = GetMainLogicAssembly();
            }
            else
            {
                if (AssemblyLoadData.Enable)
                {
                    foreach (string hotUpdateDllName in AssemblyLoadData.Instance
                                 .HotUpdateAssemblies)
                    {
                        var assetLocation = hotUpdateDllName;
                        // if (!m_enableAddressable)
                        // {
                        //     assetLocation = Utility.Path.GetRegularPath(
                        //         Path.Combine(
                        //             "Assets",
                        //             FrameworkHotUpdateSettings.Instance.AssemblyTextAssetPath,
                        //             $"{hotUpdateDllName}{FrameworkHotUpdateSettings.Instance.AssemblyTextAssetExtension}"));
                        // }

                        Log.Info($"LoadAsset: [ {assetLocation} ]");
                        m_LoadAssetCount++;
                        GameApp.Resource.LoadAsset<TextAsset>(assetLocation, LoadAssetSuccess);
                    }

                    m_LoadAssemblyWait = true;
                }
                else
                {
                    m_MainLogicAssembly = GetMainLogicAssembly();
                }
            }


            if (m_LoadAssetCount == 0)
            {
                m_LoadAssemblyComplete = true;
            }
        }


        protected override void OnUpdate(IFsm<IProcedureManager> procedureOwner, float elapseSeconds,
            float realElapseSeconds)
        {
            if (!m_LoadAssemblyComplete)
            {
                return;
            }

            if (!m_LoadMetadataAssemblyComplete)
            {
                return;
            }

            AllAssemblyLoadComplete(procedureOwner);
        }

        private void AllAssemblyLoadComplete(IFsm<IProcedureManager> procedureOwner)
        {
            ChangeState<ProcedureGameLauncherState>(procedureOwner);
#if UNITY_EDITOR
            m_MainLogicAssembly = GetMainLogicAssembly();
#endif
            if (m_MainLogicAssembly == null)
            {
                Log.Warning($"Main logic assembly missing.");
                return;
            }

            var appType = m_MainLogicAssembly.GetType(GlobalSetting.EntranceClass);
            if (appType == null)
            {
                Log.Warning($"Main logic type '{GlobalSetting.EntranceClass}' missing.");
                return;
            }

            var entryMethod = appType.GetMethod(GlobalSetting.EntranceMethod);
            if (entryMethod == null)
            {
                Log.Warning($"Main logic entry method '{GlobalSetting.EntranceMethod}' missing.");
                return;
            }

            object[] objects = new object[] { new object[] { m_HotfixAssemblys } };
            entryMethod.Invoke(appType, objects);
        }

        private Assembly GetMainLogicAssembly()
        {
            m_HotfixAssemblys.Clear();
            Assembly mainLogicAssembly = null;
            foreach (var assembly in AppDomain.CurrentDomain.GetAssemblies())
            {
                if (string.Compare(GlobalSetting.EntranceDll, $"{assembly.GetName().Name}.dll",
                        StringComparison.Ordinal) == 0)
                {
                    mainLogicAssembly = assembly;
                }

                foreach (var hotUpdateDllName in AssemblyLoadData.Instance.HotUpdateAssemblies)
                {
                    if (hotUpdateDllName == $"{assembly.GetName().Name}.dll")
                    {
                        m_HotfixAssemblys.Add(assembly);
                    }
                }

                if (mainLogicAssembly != null && m_HotfixAssemblys.Count ==
                    AssemblyLoadData.Instance.HotUpdateAssemblies.Count)
                {
                    break;
                }
            }

            return mainLogicAssembly;
        }

        /// <summary>
        /// 加载代码资源成功回调。
        /// </summary>
        /// <param name="textAsset">代码资产。</param>
        private void LoadAssetSuccess(TextAsset textAsset)
        {
            m_LoadAssetCount--;
            if (textAsset == null)
            {
                Log.Warning($"Load Assembly failed.");
                return;
            }

            var assetName = textAsset.name;
            Log.Info($"LoadAssetSuccess, assetName: [ {assetName} ]");

            try
            {
                var assembly = Assembly.Load(textAsset.bytes);
                if (string.Compare(GlobalSetting.EntranceDll, assetName, StringComparison.Ordinal) == 0)
                {
                    m_MainLogicAssembly = assembly;
                }

                m_HotfixAssemblys.Add(assembly);
                Log.Info($"Assembly [ {assembly.GetName().Name} ] loaded");
            }
            catch (Exception e)
            {
                m_FailureAssetCount++;
                Log.Error(e.Message);
                throw;
            }
            finally
            {
                m_LoadAssemblyComplete = m_LoadAssemblyWait && 0 == m_LoadAssetCount;
            }

            GameApp.Resource.UnloadAsset(textAsset);
        }

        /// <summary>
        /// 为Aot Assembly加载原始metadata， 这个代码放Aot或者热更新都行。
        /// 一旦加载后，如果AOT泛型函数对应native实现不存在，则自动替换为解释模式执行。
        /// </summary>
        public void LoadMetadataForAOTAssembly()
        {
            // 可以加载任意aot assembly的对应的dll。但要求dll必须与unity build过程中生成的裁剪后的dll一致，而不能直接使用原始dll。
            // 我们在BuildProcessor_xxx里添加了处理代码，这些裁剪后的dll在打包时自动被复制到 {项目目录}/HybridCLRData/AssembliesPostIl2CppStrip/{Target} 目录。

            // 注意，补充元数据是给AOT dll补充元数据，而不是给热更新dll补充元数据。
            // 热更新dll不缺元数据，不需要补充，如果调用LoadMetadataForAOTAssembly会返回错误
            if (AssemblyLoadData.Instance.AOTMetaAssemblies.Count == 0)
            {
                m_LoadMetadataAssemblyComplete = true;
                return;
            }

            foreach (string aotDllName in AssemblyLoadData.Instance.AOTMetaAssemblies)
            {
                var assetLocation = aotDllName;
                // if (!m_enableAddressable)
                // {
                //     assetLocation = Utility.Path.GetRegularPath(
                //         Path.Combine(
                //             "Assets",
                //             FrameworkHotUpdateSettings.Instance.AssemblyTextAssetPath,
                //             $"{aotDllName}{FrameworkHotUpdateSettings.Instance.AssemblyTextAssetExtension}"));
                // }


                Log.Info($"LoadMetadataAsset: [ {assetLocation} ]");
                m_LoadMetadataAssetCount++;
                GameApp.Resource.LoadAsset<TextAsset>(assetLocation, LoadMetadataAssetSuccess);
            }

            m_LoadMetadataAssemblyWait = true;
        }

        /// <summary>
        /// 加载元数据资源成功回调。
        /// </summary>
        /// <param name="textAsset">代码资产。</param>
        private unsafe void LoadMetadataAssetSuccess(TextAsset textAsset)
        {
            m_LoadMetadataAssetCount--;
            if (null == textAsset)
            {
                Log.Info($"LoadMetadataAssetSuccess:Load Metadata failed.");
                return;
            }

            string assetName = textAsset.name;
            Log.Info($"LoadMetadataAssetSuccess, assetName: [ {assetName} ]");
            try
            {
                byte[] dllBytes = textAsset.bytes;
                fixed (byte* ptr = dllBytes)
                {
#if ENABLE_HYBRIDCLR
                    // 加载assembly对应的dll，会自动为它hook。一旦Aot泛型函数的native函数不存在，用解释器版本代码
                    HomologousImageMode mode = HomologousImageMode.SuperSet;
                    LoadImageErrorCode err =
                        (LoadImageErrorCode)HybridCLR.RuntimeApi.LoadMetadataForAOTAssembly(dllBytes, mode);
                    Log.Warning($"LoadMetadataForAOTAssembly:{assetName}. mode:{mode} ret:{err}");
#endif
                }
            }
            catch (Exception e)
            {
                m_FailureMetadataAssetCount++;
                Log.Error(e.Message);
                throw;
            }
            finally
            {
                m_LoadMetadataAssemblyComplete = m_LoadMetadataAssemblyWait && 0 == m_LoadMetadataAssetCount;
            }

            GameApp.Resource.UnloadAsset(textAsset);
        }
    }
}