using KH.WMS.Core.Database.Repositories;
using KH.WMS.Core.DependencyInjection.ServiceLifetimes;
using Microsoft.AspNetCore.DataProtection.KeyManagement;
using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Options;
using SqlSugar;

namespace KH.WMS.Core.Database.SqlSugar;

/// <summary>
/// SQL Sugar 数据库上下文（支持事务嵌套）
/// </summary>
[RegisteredService(Lifetime = Microsoft.Extensions.DependencyInjection.ServiceLifetime.Scoped)]
public class SqlSugarDbContext : IDbContext
{
    private readonly ISqlSugarClient _sqlSugarClient;
    private readonly ILogger<SqlSugarDbContext> _logger;
    private readonly DatabaseOptions _options;

    // 事务栈，用于支持嵌套事务
    private readonly Stack<TransactionScope> _transactionScopes = new();

    public SqlSugarDbContext(
        ISqlSugarClient sqlSugarClient,
        ILogger<SqlSugarDbContext> logger,
        IOptions<DatabaseOptions> options)
    {
        _sqlSugarClient = sqlSugarClient;
        _logger = logger;
        _options = options.Value;
    }

    /// <summary>
    /// 获取当前事务隔离级别
    /// </summary>
    public System.Data.IsolationLevel? CurrentIsolationLevel =>
        _transactionScopes.Count > 0 ? _transactionScopes.Peek().IsolationLevel : null;

    public ISqlSugarClient Db => _sqlSugarClient;

    public async Task BeginTransactionAsync(System.Data.IsolationLevel isolationLevel = System.Data.IsolationLevel.ReadCommitted)
    {
        await _sqlSugarClient.Ado.BeginTranAsync(isolationLevel);
    }

    public async Task CommitTransactionAsync()
    {
        await _sqlSugarClient.Ado.CommitTranAsync();
        _logger.LogInformation("事务已提交");
    }

    public async Task RollbackTransactionAsync()
    {
        await _sqlSugarClient.Ado.RollbackTranAsync();
        _logger.LogInformation("事务已回滚");
    }

    public IRepository<T, TKey> GetRepository<T, TKey>() where T : class, new() where TKey : struct
    {
        return new RepositoryBase<T, TKey>(_sqlSugarClient, _logger);
    }

    public void Dispose()
    {
        // 如果有未提交的事务，自动回滚

        _sqlSugarClient?.Ado.RollbackTran();

        _sqlSugarClient?.Dispose();
    }

    IRepository<T, TKey> IDbContext.GetRepository<T, TKey>()
    {
        throw new NotImplementedException();
    }

    /// <summary>
    /// 事务作用域
    /// </summary>
    private class TransactionScope
    {
        public System.Data.IsolationLevel IsolationLevel { get; }
        public bool IsCompleted { get; set; }
        public bool RequiresRollback { get; set; }

        public TransactionScope(System.Data.IsolationLevel isolationLevel)
        {
            IsolationLevel = isolationLevel;
            IsCompleted = false;
            RequiresRollback = false;
        }
    }
}