using System;
using System.Collections.Generic;
using System.IO;
using System.Globalization;
using System.Text;
using UnityEngine;
using LitJson;
using GeneralTools;

/// <summary>
/// 数据持久化服务实现
/// 使用JSON格式存储应用数据，INI格式存储系统配置
/// </summary>
public class DataPersistenceService : IDataPersistenceService
{
    private readonly string _settingsPath;
    private readonly string _userPrefsPath;
    private readonly string _appConfigPath;
    private readonly string _configIniPath;
    private readonly string _streamingConfigIniPath;
    
    public DataPersistenceService()
    {
        // 设置存储路径
        var dataPath = Application.persistentDataPath;
        _settingsPath = Path.Combine(dataPath, "settings.json");
        _userPrefsPath = Path.Combine(dataPath, "UserPrefs");
        _appConfigPath = Path.Combine(dataPath, "appconfig.json");
        _configIniPath = Path.Combine(dataPath, "config.ini");
        _streamingConfigIniPath = Path.Combine(Application.streamingAssetsPath, "config.ini");
        
        // 确保目录存在
        EnsureDirectoryExists(_userPrefsPath);
        TryCopyIniToPersistent();
    }
    
    public bool SaveSettings(SystemSettings settings)
    {
        bool jsonSaved = false;
        bool iniSaved = false;

        try
        {
            var json = JsonMapper.ToJson(settings);
            jsonSaved = WriteTextAtomically(_settingsPath, json);
        }
        catch (Exception ex)
        {
            Debug.LogError($"保存JSON设置失败: {ex.Message}");
        }

        iniSaved = SaveToIniFile(settings);

        if (jsonSaved || iniSaved)
        {
            Debug.Log($"设置已保存 - JSON: {jsonSaved}, INI: {iniSaved}");
            return true;
        }

        Debug.LogError("保存设置失败：JSON和INI都未成功写入");
        return false;
    }
    
    public SystemSettings LoadSettings()
    {
        if (TryLoadJsonSettings(out var settings, out var jsonSourcePath))
        {
            ApplyNewestIniOverrides(settings, jsonSourcePath);
            return settings;
        }

        if (TryLoadIniSettings(_configIniPath, "持久化INI配置", out settings))
        {
            return settings;
        }

        if (TryLoadIniSettings(_configIniPath + ".bak", "持久化INI备份配置", out settings))
        {
            return settings;
        }

        if (File.Exists(_streamingConfigIniPath))
        {
            settings = LoadFromIniFile(_streamingConfigIniPath);
            Debug.Log($"从默认INI配置加载设置成功: {_streamingConfigIniPath}");
            return settings;
        }

        Debug.Log("使用默认设置");
        return new SystemSettings();
    }
    
    public bool SaveUserPreferences(string userId, UserPreferences preferences)
    {
        try
        {
            var filePath = Path.Combine(_userPrefsPath, $"{userId}_prefs.json");
            var json = JsonMapper.ToJson(preferences);
            File.WriteAllText(filePath, json);
            
            Debug.Log($"用户偏好已保存: {userId}");
            return true;
        }
        catch (Exception ex)
        {
            Debug.LogError($"保存用户偏好失败: {ex.Message}");
            return false;
        }
    }
    
    public UserPreferences LoadUserPreferences(string userId)
    {
        try
        {
            var filePath = Path.Combine(_userPrefsPath, $"{userId}_prefs.json");
            if (File.Exists(filePath))
            {
                var json = File.ReadAllText(filePath);
                return JsonMapper.ToObject<UserPreferences>(json);
            }
        }
        catch (Exception ex)
        {
            Debug.LogError($"加载用户偏好失败: {ex.Message}");
        }
        
        return new UserPreferences { userId = userId };
    }
    
    public bool SaveAppConfig(AppConfig config)
    {
        try
        {
            var json = JsonMapper.ToJson(config);
            File.WriteAllText(_appConfigPath, json);
            return true;
        }
        catch (Exception ex)
        {
            Debug.LogError($"保存应用配置失败: {ex.Message}");
            return false;
        }
    }
    
    public AppConfig LoadAppConfig()
    {
        try
        {
            if (File.Exists(_appConfigPath))
            {
                var json = File.ReadAllText(_appConfigPath);
                return JsonMapper.ToObject<AppConfig>(json);
            }
        }
        catch (Exception ex)
        {
            Debug.LogError($"加载应用配置失败: {ex.Message}");
        }
        
        return new AppConfig();
    }
    
    public bool ExportData(string filePath, ExportDataType dataType)
    {
        try
        {
            var exportData = new
            {
                ExportTime = DateTime.Now,
                DataType = dataType.ToString(),
                Data = GetExportData(dataType)
            };
            
            var json = JsonMapper.ToJson(exportData);
            File.WriteAllText(filePath, json);
            
            Debug.Log($"数据导出成功: {filePath}");
            return true;
        }
        catch (Exception ex)
        {
            Debug.LogError($"导出数据失败: {ex.Message}");
            return false;
        }
    }
    
    public void ClearAllData()
    {
        try
        {
            if (File.Exists(_settingsPath))
                File.Delete(_settingsPath);
            if (File.Exists(_appConfigPath))
                File.Delete(_appConfigPath);
            if (Directory.Exists(_userPrefsPath))
                Directory.Delete(_userPrefsPath, true);
                
            Debug.Log("所有持久化数据已清除");
        }
        catch (Exception ex)
        {
            Debug.LogError($"清除数据失败: {ex.Message}");
        }
    }
    
    private bool SaveToIniFile(SystemSettings settings)
    {
        try
        {
            var sb = new StringBuilder();

            AppendIniSection(sb, "Display",
                ("brightness", settings.brightness.ToString("F1", CultureInfo.InvariantCulture)));

            AppendIniSection(sb, "Audio",
                ("volume", settings.volume.ToString(CultureInfo.InvariantCulture)),
                ("muteDurationMinutes", settings.muteDurationMinutes.ToString(CultureInfo.InvariantCulture)));

            AppendIniSection(sb, "SerialPort",
                ("serialPortName", settings.serialPortName ?? string.Empty),
                ("serialBaudRate", settings.serialBaudRate.ToString(CultureInfo.InvariantCulture)),
                ("enableSerialCommunication", settings.enableSerialCommunication.ToString()));

            AppendIniSection(sb, "BFI",
                ("bfiLowThreshold", settings.bfiLowThreshold.ToString("F1", CultureInfo.InvariantCulture)),
                ("bfiHighThreshold", settings.bfiHighThreshold.ToString("F1", CultureInfo.InvariantCulture)),
                ("bfiAlarmPriority", settings.bfiAlarmPriority.ToString(CultureInfo.InvariantCulture)),
                ("enableBFIAlarm", settings.enableBFIAlarm.ToString()));

            AppendIniSection(sb, "Time",
                ("useCustomSystemTime", settings.useCustomSystemTime.ToString()),
                ("customTimeOffsetTicks", settings.customTimeOffsetTicks.ToString(CultureInfo.InvariantCulture)),
                ("systemTime", settings.systemTime == DateTime.MinValue ? string.Empty : settings.systemTime.ToString("o", CultureInfo.InvariantCulture)));

            AppendIniSection(sb, "Network",
                ("mode", settings.network.Mode.ToString()),
                ("ipv4", settings.network.IPv4 ?? string.Empty),
                ("mask", settings.network.Mask ?? string.Empty),
                ("gateway", settings.network.Gateway ?? string.Empty),
                ("dns1", settings.network.Dns1 ?? string.Empty),
                ("dns2", settings.network.Dns2 ?? string.Empty));

            AppendIniSection(sb, "System",
                ("autoBackup", settings.autoBackup.ToString()),
                ("dataRetentionDays", settings.dataRetentionDays.ToString(CultureInfo.InvariantCulture)));

            bool saved = WriteTextAtomically(_configIniPath, sb.ToString());
            if (saved)
            {
                IniFile.ClearCache(_configIniPath);
            }

            return saved;
        }
        catch (Exception ex)
        {
            Debug.LogError($"保存到INI文件失败: {ex.Message}");
            return false;
        }
    }
    
    private SystemSettings LoadFromIniFile(string iniPath)
    {
        var settings = new SystemSettings();
        
        try
        {
            IniFile.ClearCache(iniPath);

            // 显示设置，使用公开的方法
            var brightness = IniFile.ReadIniData("Display", "brightness", "50", iniPath);
            if (float.TryParse(brightness, NumberStyles.Float, CultureInfo.InvariantCulture, out float b))
                settings.brightness = b;
                
            // 音频设置
            var volume = IniFile.ReadIniData("Audio", "volume", "50", iniPath);
            if (int.TryParse(volume, NumberStyles.Integer, CultureInfo.InvariantCulture, out int v))
                settings.volume = v;
                
            var muteDuration = IniFile.ReadIniData("Audio", "muteDurationMinutes", "3", iniPath);
            if (int.TryParse(muteDuration, NumberStyles.Integer, CultureInfo.InvariantCulture, out int md))
                settings.muteDurationMinutes = md;

            var serialPortName = IniFile.ReadIniData("SerialPort", "serialPortName", settings.serialPortName, iniPath);
            if (!string.IsNullOrWhiteSpace(serialPortName))
                settings.serialPortName = serialPortName;

            var serialBaudRate = IniFile.ReadIniData("SerialPort", "serialBaudRate", settings.serialBaudRate.ToString(), iniPath);
            if (int.TryParse(serialBaudRate, NumberStyles.Integer, CultureInfo.InvariantCulture, out int sbr))
                settings.serialBaudRate = sbr;

            var enableSerial = IniFile.ReadIniData("SerialPort", "enableSerialCommunication", settings.enableSerialCommunication.ToString(), iniPath);
            if (bool.TryParse(enableSerial, out bool esc))
                settings.enableSerialCommunication = esc;

            var bfiLowThreshold = IniFile.ReadIniData("BFI", "bfiLowThreshold", settings.bfiLowThreshold.ToString(CultureInfo.InvariantCulture), iniPath);
            if (float.TryParse(bfiLowThreshold, NumberStyles.Float, CultureInfo.InvariantCulture, out float bfiLow))
                settings.bfiLowThreshold = bfiLow;

            var bfiHighThreshold = IniFile.ReadIniData("BFI", "bfiHighThreshold", settings.bfiHighThreshold.ToString(CultureInfo.InvariantCulture), iniPath);
            if (float.TryParse(bfiHighThreshold, NumberStyles.Float, CultureInfo.InvariantCulture, out float bfiHigh))
                settings.bfiHighThreshold = bfiHigh;

            var bfiAlarmPriority = IniFile.ReadIniData("BFI", "bfiAlarmPriority", settings.bfiAlarmPriority.ToString(), iniPath);
            if (int.TryParse(bfiAlarmPriority, NumberStyles.Integer, CultureInfo.InvariantCulture, out int priority))
                settings.bfiAlarmPriority = priority;

            var enableBfiAlarm = IniFile.ReadIniData("BFI", "enableBFIAlarm", settings.enableBFIAlarm.ToString(), iniPath);
            if (bool.TryParse(enableBfiAlarm, out bool enableAlarm))
                settings.enableBFIAlarm = enableAlarm;

            var useCustomSystemTime = IniFile.ReadIniData("Time", "useCustomSystemTime", settings.useCustomSystemTime.ToString(), iniPath);
            if (bool.TryParse(useCustomSystemTime, out bool customTime))
                settings.useCustomSystemTime = customTime;

            var customTimeOffsetTicks = IniFile.ReadIniData("Time", "customTimeOffsetTicks", settings.customTimeOffsetTicks.ToString(), iniPath);
            if (long.TryParse(customTimeOffsetTicks, NumberStyles.Integer, CultureInfo.InvariantCulture, out long offsetTicks))
                settings.customTimeOffsetTicks = offsetTicks;

            var systemTime = IniFile.ReadIniData("Time", "systemTime", "", iniPath);
            if (!string.IsNullOrWhiteSpace(systemTime) &&
                DateTime.TryParse(systemTime, CultureInfo.InvariantCulture, DateTimeStyles.RoundtripKind, out DateTime parsedTime))
            {
                settings.systemTime = parsedTime;
            }
                
            // 网络设置
            var networkMode = IniFile.ReadIniData("Network", "mode", "Dhcp", iniPath);
            if (Enum.TryParse<NetworkMode>(networkMode, out NetworkMode nm))
                settings.network.Mode = nm;
                
            settings.network.IPv4 = IniFile.ReadIniData("Network", "ipv4", "", iniPath);
            settings.network.Mask = IniFile.ReadIniData("Network", "mask", "", iniPath);
            settings.network.Gateway = IniFile.ReadIniData("Network", "gateway", "", iniPath);
            settings.network.Dns1 = IniFile.ReadIniData("Network", "dns1", "", iniPath);
            settings.network.Dns2 = IniFile.ReadIniData("Network", "dns2", "", iniPath);
            
            // 系统设置
            var autoBackup = IniFile.ReadIniData("System", "autoBackup", "true", iniPath);
            if (bool.TryParse(autoBackup, out bool ab))
                settings.autoBackup = ab;
                
            var dataRetention = IniFile.ReadIniData("System", "dataRetentionDays", "30", iniPath);
            if (int.TryParse(dataRetention, NumberStyles.Integer, CultureInfo.InvariantCulture, out int dr))
                settings.dataRetentionDays = dr;
        }
        catch (Exception ex)
        {
            Debug.LogError($"从INI文件加载设置失败 ({iniPath}): {ex.Message}");
        }
        
        return settings;
    }

    private static void AppendIniSection(StringBuilder builder, string sectionName, params (string Key, string Value)[] values)
    {
        builder.Append('[').Append(sectionName).AppendLine("]");
        foreach (var pair in values)
        {
            builder.Append(pair.Key).Append('=').AppendLine(pair.Value ?? string.Empty);
        }

        builder.AppendLine();
    }

    private void ApplyIniOverrides(SystemSettings settings, string iniPath)
    {
        if (settings == null || string.IsNullOrWhiteSpace(iniPath) || !File.Exists(iniPath))
        {
            return;
        }

        IniFile.ClearCache(iniPath);

        const string missing = "__DCX_SETTING_MISSING__";

        string brightness = IniFile.ReadIniData("Display", "brightness", missing, iniPath);
        if (brightness != missing && float.TryParse(brightness, NumberStyles.Float, CultureInfo.InvariantCulture, out float b))
            settings.brightness = b;

        string volume = IniFile.ReadIniData("Audio", "volume", missing, iniPath);
        if (volume != missing && int.TryParse(volume, out int v))
            settings.volume = v;

        string muteDuration = IniFile.ReadIniData("Audio", "muteDurationMinutes", missing, iniPath);
        if (muteDuration != missing && int.TryParse(muteDuration, out int md))
            settings.muteDurationMinutes = md;

        string serialPortName = IniFile.ReadIniData("SerialPort", "serialPortName", missing, iniPath);
        if (serialPortName != missing && !string.IsNullOrWhiteSpace(serialPortName))
            settings.serialPortName = serialPortName;

        string serialBaudRate = IniFile.ReadIniData("SerialPort", "serialBaudRate", missing, iniPath);
        if (serialBaudRate != missing && int.TryParse(serialBaudRate, out int sbr))
            settings.serialBaudRate = sbr;

        string enableSerial = IniFile.ReadIniData("SerialPort", "enableSerialCommunication", missing, iniPath);
        if (enableSerial != missing && bool.TryParse(enableSerial, out bool esc))
            settings.enableSerialCommunication = esc;

        string bfiLowThreshold = IniFile.ReadIniData("BFI", "bfiLowThreshold", missing, iniPath);
        if (bfiLowThreshold != missing && float.TryParse(bfiLowThreshold, NumberStyles.Float, CultureInfo.InvariantCulture, out float bfiLow))
            settings.bfiLowThreshold = bfiLow;

        string bfiHighThreshold = IniFile.ReadIniData("BFI", "bfiHighThreshold", missing, iniPath);
        if (bfiHighThreshold != missing && float.TryParse(bfiHighThreshold, NumberStyles.Float, CultureInfo.InvariantCulture, out float bfiHigh))
            settings.bfiHighThreshold = bfiHigh;

        string bfiAlarmPriority = IniFile.ReadIniData("BFI", "bfiAlarmPriority", missing, iniPath);
        if (bfiAlarmPriority != missing && int.TryParse(bfiAlarmPriority, out int priority))
            settings.bfiAlarmPriority = priority;

        string enableBfiAlarm = IniFile.ReadIniData("BFI", "enableBFIAlarm", missing, iniPath);
        if (enableBfiAlarm != missing && bool.TryParse(enableBfiAlarm, out bool enableAlarm))
            settings.enableBFIAlarm = enableAlarm;

        string useCustomSystemTime = IniFile.ReadIniData("Time", "useCustomSystemTime", missing, iniPath);
        if (useCustomSystemTime != missing && bool.TryParse(useCustomSystemTime, out bool customTime))
            settings.useCustomSystemTime = customTime;

        string customTimeOffsetTicks = IniFile.ReadIniData("Time", "customTimeOffsetTicks", missing, iniPath);
        if (customTimeOffsetTicks != missing && long.TryParse(customTimeOffsetTicks, out long offsetTicks))
            settings.customTimeOffsetTicks = offsetTicks;

        string systemTime = IniFile.ReadIniData("Time", "systemTime", missing, iniPath);
        if (systemTime != missing && !string.IsNullOrWhiteSpace(systemTime) &&
            DateTime.TryParse(systemTime, CultureInfo.InvariantCulture, DateTimeStyles.RoundtripKind, out DateTime parsedTime))
        {
            settings.systemTime = parsedTime;
        }

        string networkMode = IniFile.ReadIniData("Network", "mode", missing, iniPath);
        if (networkMode != missing && Enum.TryParse<NetworkMode>(networkMode, out NetworkMode nm))
            settings.network.Mode = nm;

        string ipv4 = IniFile.ReadIniData("Network", "ipv4", missing, iniPath);
        if (ipv4 != missing)
            settings.network.IPv4 = ipv4;

        string mask = IniFile.ReadIniData("Network", "mask", missing, iniPath);
        if (mask != missing)
            settings.network.Mask = mask;

        string gateway = IniFile.ReadIniData("Network", "gateway", missing, iniPath);
        if (gateway != missing)
            settings.network.Gateway = gateway;

        string dns1 = IniFile.ReadIniData("Network", "dns1", missing, iniPath);
        if (dns1 != missing)
            settings.network.Dns1 = dns1;

        string dns2 = IniFile.ReadIniData("Network", "dns2", missing, iniPath);
        if (dns2 != missing)
            settings.network.Dns2 = dns2;

        string autoBackup = IniFile.ReadIniData("System", "autoBackup", missing, iniPath);
        if (autoBackup != missing && bool.TryParse(autoBackup, out bool ab))
            settings.autoBackup = ab;

        string dataRetention = IniFile.ReadIniData("System", "dataRetentionDays", missing, iniPath);
        if (dataRetention != missing && int.TryParse(dataRetention, out int dr))
            settings.dataRetentionDays = dr;
    }

    private bool WriteTextAtomically(string filePath, string content)
    {
        var tempPath = string.IsNullOrWhiteSpace(filePath) ? null : filePath + ".tmp";

        try
        {
            var directory = Path.GetDirectoryName(filePath);
            if (!string.IsNullOrWhiteSpace(directory))
            {
                Directory.CreateDirectory(directory);
            }

            var backupPath = filePath + ".bak";
            byte[] bytes = new UTF8Encoding(false).GetBytes(content ?? string.Empty);

            DeleteFileIfExists(tempPath);
            WriteBytesAndFlush(tempPath, bytes);

            if (File.Exists(filePath))
            {
                try
                {
                    CopyFileSynced(filePath, backupPath);
                }
                catch (Exception ex)
                {
                    Debug.LogWarning($"备份旧配置文件失败，将继续写入新配置: {filePath}, {ex.Message}");
                }

                DeleteFileIfExists(filePath);
            }

            File.Move(tempPath, filePath);

            var fileInfo = new FileInfo(filePath);
            if (!fileInfo.Exists || fileInfo.Length != bytes.Length)
            {
                throw new IOException($"写入校验失败，期望 {bytes.Length} 字节，实际 {(fileInfo.Exists ? fileInfo.Length : 0)} 字节");
            }

            return true;
        }
        catch (Exception ex)
        {
            Debug.LogError($"原子写入失败: {filePath}, {ex.Message}");
            return false;
        }
        finally
        {
            if (!string.IsNullOrWhiteSpace(tempPath))
            {
                DeleteFileIfExists(tempPath);
            }
        }
    }

    private void TryCopyIniToPersistent()
    {
        try
        {
            if (File.Exists(_configIniPath) || File.Exists(_settingsPath))
            {
                return;
            }

            if (File.Exists(_streamingConfigIniPath))
            {
                File.Copy(_streamingConfigIniPath, _configIniPath, true);
            }
        }
        catch (Exception ex)
        {
            Debug.LogWarning($"复制默认INI到持久化目录失败: {ex.Message}");
        }
    }

    private bool TryLoadJsonSettings(out SystemSettings settings, out string sourcePath)
    {
        settings = null;
        sourcePath = null;

        string[] candidates =
        {
            _settingsPath,
            _settingsPath + ".bak",
            _settingsPath + ".tmp"
        };

        foreach (string candidate in GetExistingPathsNewestFirst(candidates))
        {
            if (TryLoadJsonSettings(candidate, out settings))
            {
                sourcePath = candidate;
                return true;
            }
        }

        return false;
    }

    private IEnumerable<string> GetExistingPathsNewestFirst(IEnumerable<string> paths)
    {
        var existingPaths = new List<string>();
        foreach (string path in paths)
        {
            if (!string.IsNullOrWhiteSpace(path) && File.Exists(path))
            {
                existingPaths.Add(path);
            }
        }

        existingPaths.Sort((left, right) => GetLastWriteTimeUtcSafe(right).CompareTo(GetLastWriteTimeUtcSafe(left)));
        return existingPaths;
    }

    private bool TryLoadJsonSettings(string path, out SystemSettings settings)
    {
        settings = null;

        if (string.IsNullOrWhiteSpace(path) || !File.Exists(path))
        {
            return false;
        }

        try
        {
            var json = File.ReadAllText(path, Encoding.UTF8);
            if (string.IsNullOrWhiteSpace(json))
            {
                throw new InvalidDataException("文件为空");
            }

            settings = JsonMapper.ToObject<SystemSettings>(json);
            if (settings == null)
            {
                throw new InvalidDataException("反序列化结果为空");
            }

            Debug.Log($"从JSON配置加载设置成功: {path}");
            return true;
        }
        catch (Exception ex)
        {
            Debug.LogWarning($"从JSON配置加载设置失败: {path}, {ex.Message}");
            settings = null;
            return false;
        }
    }

    private void ApplyNewestIniOverrides(SystemSettings settings, string jsonSourcePath)
    {
        string iniPath = GetNewestExistingPath(_configIniPath, _configIniPath + ".bak");
        if (iniPath == null)
        {
            return;
        }

        if (GetLastWriteTimeUtcSafe(iniPath) >= GetLastWriteTimeUtcSafe(jsonSourcePath))
        {
            ApplyIniOverrides(settings, iniPath);
            Debug.Log($"已合并INI覆盖项: {iniPath}");
        }
    }

    private bool TryLoadIniSettings(string path, string sourceName, out SystemSettings settings)
    {
        settings = null;
        if (string.IsNullOrWhiteSpace(path) || !File.Exists(path))
        {
            return false;
        }

        settings = LoadFromIniFile(path);
        Debug.Log($"从{sourceName}加载设置成功: {path}");
        return settings != null;
    }

    private string GetNewestExistingPath(string firstPath, string secondPath)
    {
        bool firstExists = !string.IsNullOrWhiteSpace(firstPath) && File.Exists(firstPath);
        bool secondExists = !string.IsNullOrWhiteSpace(secondPath) && File.Exists(secondPath);

        if (firstExists && secondExists)
        {
            return GetLastWriteTimeUtcSafe(secondPath) > GetLastWriteTimeUtcSafe(firstPath) ? secondPath : firstPath;
        }

        if (firstExists)
        {
            return firstPath;
        }

        return secondExists ? secondPath : null;
    }

    private DateTime GetLastWriteTimeUtcSafe(string path)
    {
        try
        {
            return !string.IsNullOrWhiteSpace(path) && File.Exists(path)
                ? File.GetLastWriteTimeUtc(path)
                : DateTime.MinValue;
        }
        catch
        {
            return DateTime.MinValue;
        }
    }

    private void WriteBytesAndFlush(string filePath, byte[] bytes)
    {
        using (var stream = new FileStream(filePath, FileMode.Create, FileAccess.Write, FileShare.Read, 4096))
        {
            stream.Write(bytes, 0, bytes.Length);
            FlushFileStream(stream);
        }
    }

    private void CopyFileSynced(string sourcePath, string targetPath)
    {
        if (string.IsNullOrWhiteSpace(sourcePath) || !File.Exists(sourcePath))
        {
            return;
        }

        byte[] bytes = File.ReadAllBytes(sourcePath);
        WriteBytesAndFlush(targetPath, bytes);
    }

    private void FlushFileStream(FileStream stream)
    {
        try
        {
            stream.Flush(true);
        }
        catch
        {
            stream.Flush();
        }
    }

    private void DeleteFileIfExists(string path)
    {
        try
        {
            if (!string.IsNullOrWhiteSpace(path) && File.Exists(path))
            {
                File.Delete(path);
            }
        }
        catch (Exception ex)
        {
            Debug.LogWarning($"删除文件失败: {path}, {ex.Message}");
        }
    }
    
    private object GetExportData(ExportDataType dataType)
    {
        switch (dataType)
        {
            case ExportDataType.Settings:
                return LoadSettings();
            case ExportDataType.UserData:
                // 导出所有用户数据
                return "用户数据导出功能待实现";
            case ExportDataType.AlarmRecords:
                // 导出报警记录
                var records = DCSAlarmManager.Instance?.GetAlarmRecords(1000);
                return records != null ? records : "无报警记录";
            case ExportDataType.PatientInfo:
                // 导出病人信息
                var patient = ServiceLocator.Get<IPatientInfoService>()?.GetCurrentPatient();
                return patient != null ? patient : "无病人信息";
            case ExportDataType.SystemLogs:
                return "系统日志导出功能待实现";
            case ExportDataType.All:
                return new
                {
                    Settings = LoadSettings(),
                    AppConfig = LoadAppConfig(),
                    SystemInfo = new
                    {
                        UnityVersion = Application.unityVersion,
                        Platform = Application.platform.ToString(),
                        SystemTime = DateTime.Now
                    }
                };
            default:
                return null;
        }
    }
    
    private void EnsureDirectoryExists(string path)
    {
        if (!Directory.Exists(path))
        {
            Directory.CreateDirectory(path);
        }
    }
}