using System.Data;
using Microsoft.Data.Sqlite;
using Milimoe.FunGame.Core.Api.Transmittal;
using Milimoe.FunGame.Core.Library.Constant;
using Milimoe.FunGame.Core.Model;

namespace Milimoe.FunGame.Server.Utility.DataUtility
{
    public class SQLiteHelper : SQLHelper
    {
        public override FunGameInfo.FunGame FunGameType { get; } = FunGameInfo.FunGame.FunGame_Server;
        public override SQLMode Mode { get; } = SQLMode.SQLite;
        public override string Script { get; set; } = "";
        public override CommandType CommandType { get; set; } = CommandType.Text;
        public override SQLResult Result => _result;
        public override SQLServerInfo ServerInfo => _serverInfo ?? SQLServerInfo.Create();
        public override int UpdateRows => _updateRows;
        public override DataSet DataSet => _dataSet;

        private readonly SqliteConnection _connection;
        private SqliteTransaction? _transaction;
        private DataSet _dataSet = new();
        private SQLResult _result = SQLResult.NotFound;
        private readonly SQLServerInfo? _serverInfo;
        private int _updateRows = 0;
        private readonly string _connectionString = "";

        public SQLiteHelper(string script = "", CommandType type = CommandType.Text)
        {
            Script = script;
            CommandType = type;
            _connectionString = ConnectProperties.GetConnectPropertiesForSQLite();
            string[] strings = _connectionString.Split("=");
            if (strings.Length > 1)
            {
                ServerHelper.WriteLine("Connect -> SQLite://" + strings[1]);
                _serverInfo = SQLServerInfo.Create(database: strings[1]);
            }
            _connection = new SqliteConnection(_connectionString);
        }

        /// <summary>
        /// 打开数据库连接
        /// </summary>
        private void OpenConnection()
        {
            if (_connection.State != ConnectionState.Open)
            {
                _connection.Open();
            }
        }

        /// <summary>
        /// 关闭数据库连接
        /// </summary>
        public override void Close()
        {
            _transaction?.Dispose();
            if (_connection.State != ConnectionState.Closed)
            {
                _connection.Close();
            }
        }

        /// <summary>
        /// 执行一个命令
        /// </summary>
        /// <returns></returns>
        public override int Execute()
        {
            return Execute(Script);
        }

        /// <summary>
        /// 执行一个指定的命令
        /// </summary>
        /// <param name="script"></param>
        /// <returns></returns>
        /// <exception cref="Exception"></exception>
        public override int Execute(string script)
        {
            try
            {
                OpenConnection();
                ServerHelper.WriteLine("SQLQuery -> " + script, InvokeMessageType.Api);
                using SqliteCommand command = new(script, _connection);
                command.CommandType = CommandType;
                if (_transaction != null)
                {
                    command.Transaction = _transaction;
                }

                _updateRows = command.ExecuteNonQuery();
                _result = SQLResult.Success;
                Close();
                return UpdateRows;
            }
            catch (Exception ex)
            {
                _result = SQLResult.Fail;
                throw new Exception($"SQL execution failed: {ex.Message}", ex);
            }
        }

        /// <summary>
        /// 查询DataSet
        /// </summary>
        /// <returns></returns>
        public override DataSet ExecuteDataSet()
        {
            return ExecuteDataSet(Script);
        }

        /// <summary>
        /// 执行指定的命令查询DataSet
        /// </summary>
        /// <param name="script"></param>
        /// <returns></returns>
        /// <exception cref="Exception"></exception>
        public override DataSet ExecuteDataSet(string script)
        {
            try
            {
                OpenConnection();
                ServerHelper.WriteLine("SQLQuery -> " + script, InvokeMessageType.Api);
                using SqliteCommand command = new(script, _connection)
                {
                    CommandType = CommandType
                };
                using SqliteDataReader reader = command.ExecuteReader();
                _dataSet = new();
                DataTable table = new();
                table.Load(reader);
                _dataSet.Tables.Add(table);
                Close();
                return _dataSet;
            }
            catch (Exception ex)
            {
                _result = SQLResult.Fail;
                throw new Exception($"SQL execution failed: {ex.Message}", ex);
            }
        }

        /// <summary>
        /// 执行指定的命令查询DataRow
        /// </summary>
        /// <returns></returns>
        public override DataRow? ExecuteDataRow()
        {
            return ExecuteDataRow(Script);
        }

        /// <summary>
        /// 执行指定的命令查询DataRow
        /// </summary>
        /// <param name="script"></param>
        /// <returns></returns>
        public override DataRow? ExecuteDataRow(string script)
        {
            OpenConnection();
            ServerHelper.WriteLine("SQLQuery -> " + script, InvokeMessageType.Api);
            DataSet dataSet = ExecuteDataSet(script);
            if (dataSet.Tables.Count > 0 && dataSet.Tables[0].Rows.Count > 0)
            {
                Close();
                return dataSet.Tables[0].Rows[0];
            }
            Close();
            return null;
        }

        /// <summary>
        /// 创建一个SQL事务
        /// </summary>
        public override void NewTransaction()
        {
            OpenConnection();
            _transaction = _connection.BeginTransaction();
        }

        /// <summary>
        /// 提交事务
        /// </summary>
        /// <exception cref="Exception"></exception>
        public override void Commit()
        {
            try
            {
                _transaction?.Commit();
                Close();
                _result = SQLResult.Success;
            }
            catch (Exception ex)
            {
                _result = SQLResult.Fail;
                throw new Exception($"Transaction commit failed: {ex.Message}", ex);
            }
        }

        /// <summary>
        /// 回滚事务
        /// </summary>
        /// <exception cref="Exception"></exception>
        public override void Rollback()
        {
            try
            {
                _transaction?.Rollback();
                Close();
                _result = SQLResult.Success;
            }
            catch (Exception ex)
            {
                _result = SQLResult.Fail;
                throw new Exception($"Transaction rollback failed: {ex.Message}", ex);
            }
        }

        /// <summary>
        /// 资源清理
        /// </summary>
        public void Dispose()
        {
            _transaction?.Dispose();
            _connection.Dispose();
        }
    }
}