using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using System.Text.RegularExpressions;
using SLSFramework.General;
using UMod;
using UMod.Scripting;
using UnityEngine;
using Object = UnityEngine.Object;

namespace SLSFramework.UModAssistance
{
    public static partial class ModManager
    {
        public static ModHost LoadMod(IModInfo modInfo)
        {
            string modName = modInfo.NameInfo.ModName;
            ModHost host = Mod.Load(Mod.DefaultDirectory.GetModPath(modName));
            LoadedMods.Add(modName, host);
            Debug.Log($"Mod '{modName}' loaded successfully.");
            return host;
        }
    }
    
    public static partial class ModManager
    {
        public static readonly SerializableDictionary<string, ModHost> LoadedMods = new SerializableDictionary<string, ModHost>();
        public static readonly Dictionary<Type, Dictionary<string, ScriptableObject>> Database = new Dictionary<Type, Dictionary<string, ScriptableObject>>();
        public static bool IsValidAssetName(string assetName) => Regex.IsMatch(assetName, @"^\w+_\w+_.+$");
        
        /// <summary>
        /// Get asset by its name, automatically determining which mod it belongs to.
        /// </summary>
        /// <param name="assetName">Name of the asset <b>MUST</b> in the format "Type_ModName_AssetName"</param>
        public static T GetAsset<T>(string assetName) where T : Object
        {
            //命名符合“Type_ModName_AssetName”格式规范
            if (IsValidAssetName(assetName))
            {
                string assumeModName = assetName.Split('_')[1];

                if (LoadedMods.TryGetValue(assumeModName, out ModHost host))
                {
                    T asset = host.Assets.Load<T>(assetName);
                    if (asset != null)
                    {
                        return asset;
                    }
                }
                
                Debug.LogWarning($"Mod '{assumeModName}' is not loaded, or cannot get asset '{assetName}'.");
            }
            else
            {
                Debug.LogError($"Please check the name format (Type_ModName_AssetName) of this asset, '{assetName}'.");
            }
            
            return null;
        }
        
        /// <summary>
        /// Get asset from specified mod.
        /// </summary>
        /// <param name="modName">Name of the mod</param>
        /// <param name="assetName">Name of the asset, recommend name format "Type_ModName_AssetName"</param>
        public static T GetAsset<T>(string modName, string assetName) where T : Object
        {
            if (!IsValidAssetName(assetName))
            {
                Debug.LogWarning($"Asset name '{assetName}' does not follow the 'Type_ModName_AssetName' format.");
            }
            
            if (LoadedMods.TryGetValue(modName, out ModHost host))
            {
                return host.Assets.Load<T>(assetName);
            }
            
            Debug.LogWarning($"Mod '{modName}' is not loaded, or cannot get asset '{assetName}'.");
            return null;
        }

        public static bool TryGetData<T>(string assetName, out T data) where T : ScriptableObject
        {
            return (data = GetData<T>(assetName)) != null;
        }
        
        /// <summary>
        /// Get data (Scriptable Objects, loaded by data manifest) from the database by its name and type.
        /// </summary>
        /// <param name="assetName">Name of the asset</param>
        public static T GetData<T>(string assetName) where T : ScriptableObject
        {
            if (!IsValidAssetName(assetName))
            {
                Debug.LogWarning($"Asset name '{assetName}' does not follow the 'Type_ModName_AssetName' format.");
            }
            
            Type assetType = typeof(T);
            if (Database.TryGetValue(assetType, out Dictionary<string, ScriptableObject> assets))
            {
                if (assets.TryGetValue(assetName, out ScriptableObject asset))
                {
                    return asset as T;
                }
                else
                {
                    Debug.LogWarning($"Data Asset '{assetName}' of type '{assetType}' not found in database.");
                    return null;
                }
            }
            else
            {
                Debug.LogWarning($"No assets of type '{assetType}' found in database.");
                return null;
            }
        }
    }
    
    public partial class ModManager
    {
        public static readonly Dictionary<string, Type> TypeRegistry = new Dictionary<string, Type>();
        
        /// <summary>
        /// 从一个已加载的Mod中，查找所有指定基类的子类，并将其注册到全局字典中。
        /// </summary>
        /// <param name="host">已加载的ModHost对象</param>
        /// <param name="baseType">要查找的基类，例如 typeof(CardLogicBase)</param>
        public static void RegisterTypesFromMod(ModHost host, Type baseType)
        {
            if (host?.ScriptDomain == null)
            {
                return;
            }

            int countBefore = TypeRegistry.Count;

            // 遍历Mod包含的所有程序集(DLLs)
            foreach (ScriptAssembly assembly in host.ScriptDomain.Assemblies)
            {
                // assembly.RawAssembly 是 uMod 封装的真实 System.Reflection.Assembly 对象
                var typesInAssembly = assembly.RawAssembly.GetTypes()
                    .Where(t => baseType.IsAssignableFrom(t) && !t.IsAbstract && !t.IsInterface);

                foreach (var type in typesInAssembly)
                {
                    if (!TypeRegistry.ContainsKey(type.Name))
                    {
                        TypeRegistry.Add(type.Name, type);
                        Debug.Log($"Registered script type '{type.FullName}' from mod '{host.CurrentMod.NameInfo.ModName}'.");
                    }
                    else
                    {
                        // 处理命名冲突：如果不同Mod中存在同名的类，后加载的会被忽略
                        Debug.LogWarning($"Duplicate script type name found: '{type.Name}'. The existing type from assembly '{TypeRegistry[type.Name].Assembly.FullName}' will be kept.");
                    }
                }
            }
        
            int countAfter = TypeRegistry.Count;
            if (countAfter > countBefore)
            {
                Debug.Log($"Registered {countAfter - countBefore} new script types deriving from '{baseType.Name}' from mod '{host.CurrentMod.NameInfo.ModName}'.");
            }
        }
        
        public static Type GetType(string typeName)
        {
            if (TypeRegistry.TryGetValue(typeName, out Type type))
            {
                return type;
            }
            Debug.LogWarning($"Type '{typeName}' not found in TypeRegistry.");
            return null;
        }
        
        public static T CreateInstance<T>(string typeName) where T : class
        {
            Type type = GetType(typeName);
            if (type != null && typeof(T).IsAssignableFrom(type))
            {
                return Activator.CreateInstance(type) as T;
            }
            Debug.LogWarning($"Cannot create instance of type '{typeName}' as it is not found or not assignable to '{typeof(T).Name}'.");
            return null;
        }
        
        public static T CreateInstance<T>(string typeName, params object[] parameters) where T : class
        {
            Type type = GetType(typeName);
            if (type != null && typeof(T).IsAssignableFrom(type))
            {
                return Activator.CreateInstance(type, parameters) as T;
            }
            Debug.LogWarning($"Cannot create instance of type '{typeName}' as it is not found or not assignable to '{typeof(T).Name}'.");
            return null;
        }
    }
}