using System.Text.Json;

namespace MiaoYu.Core.CodeGenerator.Services;

/// <summary>
/// 表元信息配置服务实现
/// </summary>
[Component]
public class TableMetaConfigService : ITableMetaConfigService, IScopedDependency
{
    private readonly IWebHostEnvironment _environment;
    private readonly ILogger<TableMetaConfigService> _logger;

    // JSON 序列化选项
    private static readonly JsonSerializerOptions _jsonOptions = new()
    {
        WriteIndented = true,
        PropertyNamingPolicy = JsonNamingPolicy.CamelCase,
        DefaultIgnoreCondition = System.Text.Json.Serialization.JsonIgnoreCondition.WhenWritingNull,
        Encoder = System.Text.Encodings.Web.JavaScriptEncoder.UnsafeRelaxedJsonEscaping
    };

    public TableMetaConfigService(IWebHostEnvironment environment, ILogger<TableMetaConfigService> logger)
    {
        _environment = environment;
        _logger = logger;
    }

    /// <summary>
    /// 获取配置文件路径
    /// </summary>
    private string GetConfigFilePath(string databaseKey, string tableName)
    {
        var baseDir = AppDomain.CurrentDomain.BaseDirectory;
        var configDir = Path.Combine(baseDir, "CodeGenConfig", databaseKey);
        
        // 确保目录存在
        if (!Directory.Exists(configDir))
        {
            Directory.CreateDirectory(configDir);
        }

        return Path.Combine(configDir, $"{tableName}.json");
    }

    /// <summary>
    /// 加载表元信息配置
    /// </summary>
    public TableMetaConfig? LoadConfig(string databaseKey, string tableName)
    {
        try
        {
            var filePath = GetConfigFilePath(databaseKey, tableName);
            
            if (!File.Exists(filePath))
            {
                return null;
            }

            var json = File.ReadAllText(filePath);
            var config = JsonSerializer.Deserialize<TableMetaConfig>(json, _jsonOptions);
            
            _logger.LogDebug("成功加载配置: {DatabaseKey}/{TableName}", databaseKey, tableName);
            
            return config;
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "加载配置文件失败: {DatabaseKey}/{TableName}", databaseKey, tableName);
            return null;
        }
    }

    /// <summary>
    /// 保存表元信息配置
    /// </summary>
    public async Task SaveConfigAsync(string databaseKey, string tableName, TableMetaConfig config)
    {
        try
        {
            var filePath = GetConfigFilePath(databaseKey, tableName);
            var json = JsonSerializer.Serialize(config, _jsonOptions);
            
            await File.WriteAllTextAsync(filePath, json);
            
            _logger.LogInformation("成功保存配置: {DatabaseKey}/{TableName}", databaseKey, tableName);
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "保存配置文件失败: {DatabaseKey}/{TableName}", databaseKey, tableName);
            throw;
        }
    }

    /// <summary>
    /// 检查配置文件是否存在
    /// </summary>
    public bool ExistsConfig(string databaseKey, string tableName)
    {
        var filePath = GetConfigFilePath(databaseKey, tableName);
        return File.Exists(filePath);
    }

    /// <summary>
    /// 删除配置文件
    /// </summary>
    public async Task DeleteConfigAsync(string databaseKey, string tableName)
    {
        try
        {
            var filePath = GetConfigFilePath(databaseKey, tableName);
            
            if (File.Exists(filePath))
            {
                await Task.Run(() => File.Delete(filePath));
                _logger.LogInformation("成功删除配置: {DatabaseKey}/{TableName}", databaseKey, tableName);
            }
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "删除配置文件失败: {DatabaseKey}/{TableName}", databaseKey, tableName);
            throw;
        }
    }
}