using Godot;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text.Json;

namespace TheGame
{
    public class SaveData
    {
        public GameSeed GameSeed { get; set; }
        public List<SaveInstance> Instances { get; set; } = new List<SaveInstance>();
        
        // Backward compatibility
        public float GameTime { get; set; }
        public DateTime SaveDate { get; set; }
        public string SaveName { get; set; }
        public string DisplayName { get; set; } = "";
        
        public SaveData()
        {
            GameSeed = new GameSeed();
        }
        
        public SaveData(GameSeed gameSeed)
        {
            GameSeed = gameSeed;
        }
        
        public SaveInstance GetLatestInstance()
        {
            if (Instances.Count == 0) return null;
            return Instances.OrderByDescending(i => i.SaveDate).First();
        }
        
        public SaveInstance GetInstanceWithHighestGameTime()
        {
            if (Instances.Count == 0) return null;
            return Instances.OrderByDescending(i => i.GameTime).First();
        }
    }
    
    public class SaveManager
    {
        private readonly string _saveDirectory;
        
        public SaveManager()
        {
            // Använd user data directory istället för executable directory
            string userDataDir = OS.GetUserDataDir();
            _saveDirectory = Path.Combine(userDataDir, "saves");
            
            // Skapa saves mapp om den inte finns
            if (!Directory.Exists(_saveDirectory))
            {
                Directory.CreateDirectory(_saveDirectory);
                GD.Print($"Created saves directory: {_saveDirectory}");
            }
            else
            {
                GD.Print($"Using saves directory: {_saveDirectory}");
            }
        }
        
        public bool SaveGame(float gameTime, string displayName = "", GameSeed gameSeed = null, bool overwriteLatest = true)
        {
            try
            {
                // Om ingen seed angiven, använd nuvarande eller skapa ny
                if (gameSeed == null)
                {
                    gameSeed = GameState.CurrentGameSeed ?? new GameSeed();
                    GameState.CurrentGameSeed = gameSeed;
                }
                
                // Sök efter befintlig SaveData för denna seed
                var existingSaveData = FindSaveDataBySeed(gameSeed);
                
                if (existingSaveData == null)
                {
                    // Skapa ny SaveData för denna seed
                    existingSaveData = new SaveData(gameSeed);
                }
                
                // Skapa ny instans
                var newInstance = new SaveInstance(gameTime, displayName);
                
                if (overwriteLatest && existingSaveData.Instances.Count > 0)
                {
                    // Skriv över den senaste instansen
                    var latestInstance = existingSaveData.GetLatestInstance();
                    existingSaveData.Instances.Remove(latestInstance);
                }
                
                existingSaveData.Instances.Add(newInstance);
                
                // Spara till fil
                bool saveSuccess = SaveSeedToFile(existingSaveData);
                
                if (saveSuccess)
                {
                    GD.Print($"Game saved - Seed: {gameSeed.SeedValue}, Instance: {newInstance.DisplayName}");
                    return true;
                }
                else
                {
                    GD.PrintErr($"Failed to save game - Seed: {gameSeed.SeedValue}");
                    return false;
                }
            }
            catch (Exception ex)
            {
                GD.PrintErr($"Error saving game: {ex.Message}");
                return false;
            }
        }
        
        public SaveData FindSaveDataBySeed(GameSeed gameSeed)
        {
            string fileName = $"seed_{gameSeed.SeedValue}.json";
            string filePath = Path.Combine(_saveDirectory, fileName);
            
            if (File.Exists(filePath))
            {
                try
                {
                    string jsonString = File.ReadAllText(filePath);
                    var saveData = JsonSerializer.Deserialize<SaveData>(jsonString);
                    return saveData;
                }
                catch (Exception ex)
                {
                    GD.PrintErr($"Failed to load seed file {filePath}: {ex.Message}");
                }
            }
            
            return null;
        }
        
        private bool SaveSeedToFile(SaveData saveData)
        {
            string fileName = $"seed_{saveData.GameSeed.SeedValue}.json";
            string filePath = Path.Combine(_saveDirectory, fileName);
            
            try
            {
                string jsonString = JsonSerializer.Serialize(saveData, new JsonSerializerOptions 
                { 
                    WriteIndented = true 
                });
                File.WriteAllText(filePath, jsonString);
                GD.Print($"Seed saved to: {filePath}");
                return true;
            }
            catch (Exception ex)
            {
                GD.PrintErr($"Failed to save seed file: {ex.Message}");
                return false;
            }
        }
        
        public List<SaveData> GetSavedGames()
        {
            var savedGames = new List<SaveData>();
            
            GD.Print($"Looking for saves in: {_saveDirectory}");
            
            if (!Directory.Exists(_saveDirectory))
            {
                GD.Print("Save directory does not exist");
                return savedGames;
            }
            
            try
            {
                // Ladda både nya seed-filer och gamla format för backward compatibility
                var allFiles = Directory.GetFiles(_saveDirectory, "*.json");
                GD.Print($"Found {allFiles.Length} save files");
                
                foreach (string filePath in allFiles)
                {
                    GD.Print($"Processing save file: {filePath}");
                    try
                    {
                        string jsonString = File.ReadAllText(filePath);
                        
                        if (Path.GetFileName(filePath).StartsWith("seed_"))
                        {
                            // Ny seed-baserad fil
                            var saveData = JsonSerializer.Deserialize<SaveData>(jsonString);
                            if (saveData != null && saveData.Instances.Count > 0)
                            {
                                savedGames.Add(saveData);
                                GD.Print($"Successfully loaded seed: {saveData.GameSeed.SeedValue} with {saveData.Instances.Count} instances");
                            }
                        }
                        else
                        {
                            // Gammal fil - konvertera till nytt format
                            var oldSaveData = JsonSerializer.Deserialize<Dictionary<string, object>>(jsonString);
                            if (oldSaveData != null)
                            {
                                var convertedSave = ConvertOldSaveFormat(oldSaveData);
                                if (convertedSave != null)
                                {
                                    savedGames.Add(convertedSave);
                                    GD.Print($"Converted old save format");
                                }
                            }
                        }
                    }
                    catch (Exception ex)
                    {
                        GD.PrintErr($"Failed to load save file {filePath}: {ex.Message}");
                    }
                }
                
                // Sortera efter senaste aktivitet
                savedGames = savedGames.OrderByDescending(s => s.GetLatestInstance()?.SaveDate ?? DateTime.MinValue).ToList();
                GD.Print($"Total loaded saves: {savedGames.Count}");
            }
            catch (Exception ex)
            {
                GD.PrintErr($"Failed to read saves directory: {ex.Message}");
            }
            
            return savedGames;
        }
        
        private SaveData ConvertOldSaveFormat(Dictionary<string, object> oldData)
        {
            try
            {
                // Extrahera värden från gammal format
                var gameTime = Convert.ToSingle(oldData.GetValueOrDefault("GameTime", 0f));
                var saveDateStr = oldData.GetValueOrDefault("SaveDate", "")?.ToString();
                var displayName = oldData.GetValueOrDefault("DisplayName", "")?.ToString();
                
                if (DateTime.TryParse(saveDateStr, out DateTime saveDate))
                {
                    var gameSeed = new GameSeed($"OLD_{DateTime.Now.Ticks % 100000000:X}", "Converted Save");
                    var saveData = new SaveData(gameSeed);
                    
                    var instance = new SaveInstance(gameTime, displayName ?? "Converted Save");
                    instance.SaveDate = saveDate;
                    saveData.Instances.Add(instance);
                    
                    return saveData;
                }
            }
            catch (Exception ex)
            {
                GD.PrintErr($"Failed to convert old save format: {ex.Message}");
            }
            
            return null;
        }
        
        public bool LoadGame(SaveData saveData, SaveInstance instance = null)
        {
            try
            {
                // Om ingen specifik instans angiven, ta den med högst speltid
                if (instance == null)
                {
                    instance = saveData.GetInstanceWithHighestGameTime();
                }
                
                if (instance == null)
                {
                    GD.PrintErr("No valid instance found to load");
                    return false;
                }
                
                GameState.LoadedGameTime = instance.GameTime;
                GameState.CurrentGameSeed = saveData.GameSeed;
                GameState.LoadedInstance = instance;
                
                GD.Print($"Loaded game - Seed: {saveData.GameSeed.SeedValue}, Instance: {instance.DisplayName}, Time: {instance.GetFormattedGameTime()}");
                return true;
            }
            catch (Exception ex)
            {
                GD.PrintErr($"Failed to load game: {ex.Message}");
                return false;
            }
        }
    }
}