using System;
using System.Collections;
using System.Collections.Generic;
using System.IO;
using UnityEngine;

namespace RR.Common.Settings
{
    [Serializable]
    public class SettingsSaveData
    {
        public int version = 1;
        public List<Entry> entries = new();

        [Serializable]
        public class Entry
        {
            public string key;
            public SettingValue value;
        }
    }

    [DefaultExecutionOrder(-900)]
    public class SettingsManager : MonoBehaviour
    {
        [SerializeField] private SettingsDatabase database;

        public static SettingsManager Instance { get; private set; }

        private readonly Dictionary<string, SettingValue> map = new();
        private string path;
        private Coroutine saveRoutine;
        
        // События для совместимости со старым кодом
        public event Action OnSettingsLoaded;
        public event Action OnSettingsSaved;
        public event Action<string, SettingValue> OnSettingChanged;

        private void Awake()
        {
            Debug.Log($"[SettingsManager] Awake called. Instance = {(Instance != null ? Instance.name : "null")}");
            
            if (Instance)
            {
                Debug.Log("[SettingsManager] Instance already exists, destroying this one.");
                Destroy(gameObject);
                return;
            }

            Instance = this;
            Debug.Log($"[SettingsManager] Instance set to {name}");
            DontDestroyOnLoad(gameObject);

            path = Path.Combine(Application.persistentDataPath, "settings.json");

            if (!database)
            {
                Debug.LogError("[SettingsManager] Database is not assigned! Settings will not work.");
            }
            else
            {
                Debug.Log($"[SettingsManager] Initialized with database containing {database.entries.Count} entries.");
            }

            LoadOrDefaults();
            ApplyAll();
        }
        
        /// <summary>
        /// Инициализация из GameManager (альтернатива Awake)
        /// </summary>
        public void Initialize()
        {
            if (Instance != null && Instance != this)
            {
                Destroy(gameObject);
                return;
            }

            Instance = this;
            DontDestroyOnLoad(gameObject);
            
            // Если database не назначена - пытаемся загрузить из Resources
            if (!database)
            {
                database = Resources.Load<SettingsDatabase>("SettingsDatabase");
                if (!database)
                {
                    // Пытаемся найти л��бую SettingsDatabase в проекте
                    var databases = Resources.FindObjectsOfTypeAll<SettingsDatabase>();
                    if (databases.Length > 0)
                    {
                        database = databases[0];
                    }
                }
            }
            
            if (!database)
            {
                Debug.LogError("[SettingsManager] Database is not assigned and not found in Resources! Settings will not work.");
            }
            else
            {
                Debug.Log($"[SettingsManager] Initialized with database containing {database.entries.Count} entries.");
            }

            path = Path.Combine(Application.persistentDataPath, "settings.json");

            LoadOrDefaults();
            ApplyAll();
        }

        public SettingEntry Define(string key)
        {
            if (!database)
            {
                Debug.LogWarning($"[SettingsManager] Database is null, cannot define key '{key}'");
                return null;
            }
            return database.Find(key);
        }

        public SettingValue Get(string key)
        {
            if (map.TryGetValue(key, out SettingValue v)) return v;
            SettingEntry def = Define(key);
            return def?.DefaultValue ?? default;
        }
        
        // Удобные типизированные геттеры
        public bool GetBool(string key) => Get(key).b;
        public int GetInt(string key) => Get(key).i;
        public float GetFloat(string key) => Get(key).f;
        public string GetString(string key) => Get(key).s;

        public void Set(string key, SettingValue value)
        {
            // Проверяем, что объект не уничтожен
            if (this == null) return;
            
            SettingEntry def = Define(key);
            if (def == null)
            {
                Debug.LogWarning($"[SettingsManager] No definition found for key '{key}'. Check that SettingsDatabase has this entry.");
                return;
            }

            SettingValue clean = def.Sanitize(value);
            map[key] = clean;
            
            Debug.Log($"[SettingsManager] Set '{key}' = {value.type}: b={value.b}, i={value.i}, f={value.f}, s={value.s}");

            // применяем СРАЗУ
            SettingsApplier.Apply(def, clean);
            
            // оповещаем подписчиков
            OnSettingChanged?.Invoke(key, clean);

            // сохраняем с небольшой задержкой (удобно для слайдеров)
            ScheduleSave(0.25f);
        }
        
        // Удобные типизированные сеттеры
        public void SetBool(string key, bool value) => Set(key, SettingValue.Bool(value));
        public void SetInt(string key, int value) => Set(key, SettingValue.Int(value));
        public void SetFloat(string key, float value) => Set(key, SettingValue.Float(value));
        public void SetString(string key, string value) => Set(key, SettingValue.String(value));
        
        /// <summary>
        /// Изменяет настройку извне (с проверкой флага exposed)
        /// </summary>
        public bool SetExternal(string key, SettingValue value)
        {
            if (this == null) return false;
            
            SettingEntry def = Define(key);
            if (def == null)
            {
                Debug.LogWarning($"[SettingsManager] No definition found for key '{key}'.");
                return false;
            }
            
            if (!def.exposed)
            {
                Debug.LogWarning($"[SettingsManager] Setting '{key}' is not exposed for external changes. Set 'exposed' flag to true in SettingsDatabase.");
                return false;
            }
            
            Set(key, value);
            return true;
        }
        
        // Удобные типизированные сеттеры для внешних изменений
        public bool SetExternalBool(string key, bool value) => SetExternal(key, SettingValue.Bool(value));
        public bool SetExternalInt(string key, int value) => SetExternal(key, SettingValue.Int(value));
        public bool SetExternalFloat(string key, float value) => SetExternal(key, SettingValue.Float(value));
        public bool SetExternalString(string key, string value) => SetExternal(key, SettingValue.String(value));
        
        /// <summary>
        /// Немедленное сохранение настроек
        /// </summary>
        public void SaveSettings()
        {
            SaveNow();
        }
        
        /// <summary>
        /// Перезагружает настройки из файла (только exposed настройки)
        /// Полезно для hot-reload при изменении файла извне
        /// </summary>
        public void ReloadFromFile()
        {
            if (!File.Exists(path))
            {
                Debug.LogWarning($"[SettingsManager] Settings file not found: {path}");
                return;
            }

            try
            {
                string json = File.ReadAllText(path);
                SettingsSaveData data = JsonUtility.FromJson<SettingsSaveData>(json);
                if (data != null)
                {
                    foreach (SettingsSaveData.Entry e in data.entries)
                    {
                        if (string.IsNullOrWhiteSpace(e.key)) continue;
                        
                        SettingEntry def = Define(e.key);
                        if (def == null)
                        {
                            Debug.LogWarning($"[SettingsManager] Unknown setting key '{e.key}' in file.");
                            continue;
                        }
                        
                        // Проверяем флаг exposed
                        if (!def.exposed)
                        {
                            Debug.LogWarning($"[SettingsManager] Skipping '{e.key}' - not exposed for external changes.");
                            continue;
                        }
                        
                        // Применяем настройку
                        SettingValue clean = def.Sanitize(e.value);
                        map[e.key] = clean;
                        SettingsApplier.Apply(def, clean);
                        OnSettingChanged?.Invoke(e.key, clean);
                    }
                    
                    Debug.Log($"[SettingsManager] Reloaded settings from {path}");
                }
            }
            catch (Exception ex)
            {
                Debug.LogError($"[SettingsManager] Failed to reload settings: {ex.Message}");
            }
        }

        public void ApplyAll()
        {
            if (!database) return;
            foreach (SettingEntry def in database.entries)
            {
                if (def == null || string.IsNullOrWhiteSpace(def.key)) continue;
                SettingsApplier.Apply(def, Get(def.key));
            }
        }

        public void ResetAllToDefaults()
        {
            if (!database) return;

            foreach (SettingEntry def in database.entries)
            {
                if (def == null || string.IsNullOrWhiteSpace(def.key)) continue;
                map[def.key] = def.DefaultValue;
                SettingsApplier.Apply(def, def.DefaultValue);
            }

            ScheduleSave(0.05f);
        }
        
        /// <summary>
        /// Сбрасывает настройки указанной группы к значениям по умолчанию
        /// </summary>
        /// <param name="groupName">Имя группы настроек</param>
        public void ResetGroupToDefaults(string groupName)
        {
            if (!database || string.IsNullOrWhiteSpace(groupName)) return;

            foreach (SettingEntry def in database.entries)
            {
                if (def == null || string.IsNullOrWhiteSpace(def.key)) continue;
                if (!string.Equals(def.group, groupName, System.StringComparison.OrdinalIgnoreCase)) continue;
                
                map[def.key] = def.DefaultValue;
                SettingsApplier.Apply(def, def.DefaultValue);
            }

            ScheduleSave(0.05f);
        }

        private void LoadOrDefaults()
        {
            LoadOrDefaults(checkExposed: false);
        }
        
        private void LoadOrDefaults(bool checkExposed)
        {
            map.Clear();

            if (File.Exists(path))
            {
                try
                {
                    string json = File.ReadAllText(path);
                    SettingsSaveData data = JsonUtility.FromJson<SettingsSaveData>(json);
                    if (data != null)
                    {
                        foreach (SettingsSaveData.Entry e in data.entries)
                        {
                            if (string.IsNullOrWhiteSpace(e.key)) continue;
                            
                            // Если checkExposed = true, проверяем флаг exposed
                            if (checkExposed)
                            {
                                SettingEntry def = Define(e.key);
                                if (def != null && !def.exposed)
                                {
                                    Debug.LogWarning($"[SettingsManager] Skipping '{e.key}' from file - not exposed.");
                                    continue;
                                }
                            }
                            
                            map[e.key] = e.value;
                        }
                    }
                }
                catch
                {
                    // если файл битый — просто упадём на дефолты ниже
                }
            }

            if (!database) return;

            foreach (SettingEntry def in database.entries)
            {
                if (def == null || string.IsNullOrWhiteSpace(def.key)) continue;

                if (!map.ContainsKey(def.key))
                    map[def.key] = def.DefaultValue;
                else
                    map[def.key] = def.Sanitize(map[def.key]);
            }
            
            OnSettingsLoaded?.Invoke();
        }

        private void ScheduleSave(float delay)
        {
            // Проверяем, что объект не уничтожен
            if (this == null || !gameObject) return;
            
            if (saveRoutine != null) StopCoroutine(saveRoutine);
            saveRoutine = StartCoroutine(SaveDelayed(delay));
        }

        private IEnumerator SaveDelayed(float delay)
        {
            yield return new WaitForSecondsRealtime(delay);
            SaveNow();
            saveRoutine = null;
        }

        private void SaveNow()
        {
            SettingsSaveData data = new();

            foreach (var kv in map)
                data.entries.Add(new SettingsSaveData.Entry { key = kv.Key, value = kv.Value });

            try
            {
                File.WriteAllText(path, JsonUtility.ToJson(data, true));
                OnSettingsSaved?.Invoke();
            }
            catch (Exception e)
            {
                Debug.LogWarning($"[SettingsManager] Save failed: {e.Message}");
            }
        }

        private void OnApplicationQuit() => SaveNow();
    }
}