using NFine.Code;
using System;
using System.Configuration;
using System.Data;
using System.Data.Common;
using System.Data.SqlClient;

namespace NFine.Data.Extensions
{
    public class DbHelper
    {
        /// <summary>
        /// 调试日志
        /// </summary>
        //public static LogHelper log = LogFactory.GetLogger(typeof(DbHelper));

        /// <summary>
        /// 连接字符串
        /// </summary>
        public static string ConnectionString { get; set; }
        /// <summary>
        /// 数据库类型
        /// </summary>
        public static DatabaseType DbType { get; set; }
        /// <summary>
        /// 数据库命名参数符号
        /// </summary>
        public static string DbParmChar { get; set; }
        public DbHelper(string connstring)
        {
            string ConStringDESEncrypt = ConfigurationManager.ConnectionStrings["connstr"].ConnectionString;
            ConnectionString = ConfigurationManager.ConnectionStrings["connstr"].ConnectionString;
            if (ConStringDESEncrypt == "true")
            {
                ConnectionString = DESEncrypt.Decrypt(ConnectionString);
            }
            this.DatabaseTypeEnumParse(ConfigurationManager.ConnectionStrings["connstr"].ProviderName);
            DbParmChar = DbFactory.CreateDbParmCharacter();
        }
        /// <summary>
        /// 执行 SQL 语句，并返回受影响的行数。
        /// </summary>
        /// <param name="cmdType">执行命令的类型（存储过程或T-SQL，等等）</param>
        /// <param name="cmdText">存储过程名称或者T-SQL命令行</param>
        /// <param name="parameters">执行命令所需的sql语句对应参数</param>
        /// <returns></returns>
        public static int ExecuteNonQuery(CommandType cmdType, string cmdText, params DbParameter[] parameters)
        {
            int num = 0;
            try
            {
                DbCommand cmd = DbFactory.CreateDbCommand();
                using (DbConnection conn = DbFactory.CreateDbConnection(ConnectionString))
                {
                    PrepareCommand(cmd, conn, null, cmdType, cmdText, parameters);
                    num = cmd.ExecuteNonQuery();
                    cmd.Parameters.Clear();
                }
            }
            catch (Exception ex)
            {
                num = -1;
                //log.Error(ex.Message);
            }
            return num;
        }
        /// <summary>
        /// 执行 SQL 语句，并返回受影响的行数。
        /// </summary>
        /// <param name="cmdType">执行命令的类型（存储过程或T-SQL，等等）</param>
        /// <param name="cmdText">存储过程名称或者T-SQL命令行</param>
        /// <returns></returns>
        public static int ExecuteNonQuery(CommandType cmdType, string cmdText)
        {
            int num = 0;
            try
            {
                DbCommand cmd = DbFactory.CreateDbCommand();
                using (DbConnection conn = DbFactory.CreateDbConnection(ConnectionString))
                {
                    PrepareCommand(cmd, conn, null, cmdType, cmdText, null);
                    num = cmd.ExecuteNonQuery();
                    cmd.Parameters.Clear();
                }
            }
            catch (Exception ex)
            {
                num = -1;
                //log.Error(ex.Message);
            }
            return num;
        }
        /// <summary>
        /// 执行 SQL 语句，并返回受影响的行数。
        /// </summary>
        /// <param name="conn">数据库连接对象</param>
        /// <param name="cmdType">执行命令的类型（存储过程或T-SQL，等等）</param>
        /// <param name="cmdText">存储过程名称或者T-SQL命令行</param>
        /// <param name="parameters">执行命令所需的sql语句对应参数</param>
        /// <returns></returns>
        public static int ExecuteNonQuery(DbConnection connection, CommandType cmdType, string cmdText, params DbParameter[] parameters)
        {
            int num = 0;
            try
            {
                DbCommand cmd = DbFactory.CreateDbCommand();
                PrepareCommand(cmd, connection, null, cmdType, cmdText, parameters);
                num = cmd.ExecuteNonQuery();
                cmd.Parameters.Clear();
            }
            catch (Exception ex)
            {
                num = -1;
                //log.Error(ex.Message);
            }
            return num;
        }
        /// <summary>
        /// 执行 SQL 语句，并返回受影响的行数。
        /// </summary>
        /// <param name="conn">数据库连接对象</param>
        /// <param name="cmdType">执行命令的类型（存储过程或T-SQL，等等）</param>
        /// <param name="cmdText">存储过程名称或者T-SQL命令行</param>
        /// <returns></returns>
        public static int ExecuteNonQuery(DbConnection connection, CommandType cmdType, string cmdText)
        {
            int num = 0;
            try
            {
                DbCommand cmd = DbFactory.CreateDbCommand();
                PrepareCommand(cmd, connection, null, cmdType, cmdText, null);
                num = cmd.ExecuteNonQuery();
                cmd.Parameters.Clear();
            }
            catch (Exception ex)
            {
                num = -1;
                //log.Error(ex.Message);
            }
            return num;
        }
        /// <summary>
        /// 执行 SQL 语句，并返回受影响的行数。
        /// </summary>
        /// <param name="isOpenTrans">事务对象</param>
        /// <param name="cmdType">执行命令的类型（存储过程或T-SQL，等等）</param>
        /// <param name="cmdText">存储过程名称或者T-SQL命令行</param>
        /// <param name="parameters">执行命令所需的sql语句对应参数</param>
        /// <returns></returns>
        public static int ExecuteNonQuery(DbTransaction isOpenTrans, CommandType cmdType, string cmdText, params DbParameter[] parameters)
        {
            int num = 0;
            try
            {
                DbCommand cmd = DbFactory.CreateDbCommand();
                if (isOpenTrans == null || isOpenTrans.Connection == null)
                {
                    using (DbConnection conn = DbFactory.CreateDbConnection(ConnectionString))
                    {
                        PrepareCommand(cmd, conn, isOpenTrans, cmdType, cmdText, parameters);
                        num = cmd.ExecuteNonQuery();
                    }
                }
                else
                {
                    PrepareCommand(cmd, isOpenTrans.Connection, isOpenTrans, cmdType, cmdText, parameters);
                    num = cmd.ExecuteNonQuery();
                }
                cmd.Parameters.Clear();
            }
            catch (Exception ex)
            {
                num = -1;
                //log.Error(ex.Message);
            }
            return num;
        }
        /// <summary>
        /// 执行 SQL 语句，并返回受影响的行数。
        /// </summary>
        /// <param name="isOpenTrans">事务对象</param>
        /// <param name="cmdType">执行命令的类型（存储过程或T-SQL，等等）</param>
        /// <param name="cmdText">存储过程名称或者T-SQL命令行</param>
        /// <returns></returns>
        public static int ExecuteNonQuery(DbTransaction isOpenTrans, CommandType cmdType, string cmdText)
        {
            int num = 0;
            try
            {
                DbCommand cmd = DbFactory.CreateDbCommand();
                PrepareCommand(cmd, isOpenTrans.Connection, isOpenTrans, cmdType, cmdText, null);
                num = cmd.ExecuteNonQuery();
                cmd.Parameters.Clear();
            }
            catch (Exception ex)
            {
                num = -1;
                //log.Error(ex.Message);
            }
            return num;
        }
        /// <summary>
        /// 使用提供的参数，执行有结果集返回的数据库操作命令、并返回SqlDataReader对象
        /// </summary>
        /// <param name="isOpenTrans">事务对象</param>
        /// <param name="commandType">执行命令的类型（存储过程或T-SQL，等等）</param>
        /// <param name="commandText">存储过程名称或者T-SQL命令行<</param>
        /// <param name="parameters">执行命令所需的sql语句对应参数</param>
        /// <returns>返回SqlDataReader对象</returns>
        public static IDataReader ExecuteReader(DbTransaction isOpenTrans, CommandType cmdType, string cmdText, params DbParameter[] parameters)
        {
            DbCommand cmd = DbFactory.CreateDbCommand();
            DbConnection conn = DbFactory.CreateDbConnection(ConnectionString);
            try
            {
                PrepareCommand(cmd, conn, isOpenTrans, cmdType, cmdText, parameters);
                IDataReader rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
                cmd.Parameters.Clear();
                return rdr;
            }
            catch (Exception ex)
            {
                conn.Close();
                cmd.Dispose();
                //log.Error(ex.Message);
                throw;
            }
        }

        public static SqlDataReader ExecuteReader(string connectionString, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters)
        {
            SqlCommand cmd = new SqlCommand();
            SqlConnection conn = new SqlConnection(connectionString);

            // we use a try/catch here because if the method throws an exception we want to 
            // close the connection throw code, because no datareader will exist, hence the 
            // commandBehaviour.CloseConnection will not work
            try
            {
                PrepareCommand(cmd, conn, null, cmdType, cmdText, commandParameters);
                SqlDataReader rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
                cmd.Parameters.Clear();
                return rdr;
            }
            catch
            {
                conn.Close();
                throw;
            }
        }

        /// <summary>
        /// 返回一个数据表
        /// </summary>
        /// <param name="connectionString">数据库连接字符串</param>
        /// <param name="cmdType">命令类型</param>
        /// <param name="cmdText">SQL语句</param>
        /// <param name="commandParameters">参数</param>
        /// <param name="strTableName">数据表名</param>
        /// <param name="bIsLoadStru">是否加载数据表结构</param>
        /// <returns></returns>
        public static DataTable ExecuteTable(string connectionString, CommandType cmdType, string cmdText, bool bIsLoadStru, params SqlParameter[] commandParameters)
        {
            using (SqlConnection connection = new SqlConnection(connectionString))
            {
                DataTable dt = ExecuteTable(connection, cmdType, cmdText, bIsLoadStru, commandParameters);
                connection.Close();

                return dt;
            }
        }

        /// <summary>
        /// 返回一个数据表
        /// </summary>
        /// <param name="connection">数据库连接</param>
        /// <param name="cmdType">命令类型</param>
        /// <param name="cmdText">SQL语句</param>
        /// <param name="commandParameters">参数</param>
        /// <param name="strTableName">数据表名</param>
        /// <param name="bIsLoadStru">是否加载数据表结构</param>
        /// <returns></returns>
        public static DataTable ExecuteTable(SqlConnection connection, CommandType cmdType, string cmdText, bool bIsLoadStru, params SqlParameter[] commandParameters)
        {
            DataSet ds = new DataSet();
            SqlCommand cmd = new SqlCommand();
            PrepareCommand(cmd, connection, null, cmdType, cmdText, commandParameters);
            SqlDataAdapter da = new SqlDataAdapter(cmd);
            if (bIsLoadStru)
            {
                da.FillSchema(ds, SchemaType.Source);
            }
            da.Fill(ds);
            cmd.Parameters.Clear();

            return ds.Tables[0];
        }

        public static int ExecuteNonQuery(string connectionString, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters)
        {

            SqlCommand cmd = new SqlCommand();

            using (SqlConnection conn = new SqlConnection(connectionString))
            {
                PrepareCommand(cmd, conn, null, cmdType, cmdText, commandParameters);
                int val = cmd.ExecuteNonQuery();
                cmd.Parameters.Clear();
                return val;
            }
        }

        /// <summary>
        /// 使用提供的参数，执行有结果集返回的数据库操作命令、并返回SqlDataReader对象
        /// </summary>
        /// <param name="commandType">执行命令的类型（存储过程或T-SQL，等等）</param>
        /// <param name="commandText">存储过程名称或者T-SQL命令行<</param>
        /// <param name="parameters">执行命令所需的sql语句对应参数</param>
        /// <returns>返回SqlDataReader对象</returns>
        public static IDataReader ExecuteReader(CommandType cmdType, string cmdText, params DbParameter[] parameters)
        {
            DbCommand cmd = DbFactory.CreateDbCommand();
            DbConnection conn = DbFactory.CreateDbConnection(ConnectionString);
            try
            {
                PrepareCommand(cmd, conn, null, cmdType, cmdText, parameters);
                IDataReader rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
                cmd.Parameters.Clear();
                return rdr;
            }
            catch (Exception ex)
            {
                conn.Close();
                cmd.Dispose();
                //log.Error(ex.Message);
                throw;
            }
        }
        /// <summary>
        ///使用提供的参数，执行有结果集返回的数据库操作命令、并返回SqlDataReader对象
        /// </summary>
        /// <param name="commandType">执行命令的类型（存储过程或T-SQL，等等）</param>
        /// <param name="commandText">存储过程名称或者T-SQL命令行<</param>
        /// <returns>返回SqlDataReader对象</returns>
        public static IDataReader ExecuteReader(CommandType cmdType, string cmdText)
        {
            DbCommand cmd = DbFactory.CreateDbCommand();
            DbConnection conn = DbFactory.CreateDbConnection(ConnectionString);
            try
            {
                PrepareCommand(cmd, conn, null, cmdType, cmdText, null);
                IDataReader rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
                cmd.Parameters.Clear();
                return rdr;
            }
            catch (Exception ex)
            {
                conn.Close();
                cmd.Dispose();
                //log.Error(ex.Message);
                throw;
            }
        }
        /// <summary>
        /// 查询数据填充到数据集DataSet中
        /// </summary>
        /// <param name="cmdType">执行命令的类型（存储过程或T-SQL，等等）</param>
        /// <param name="cmdText">命令文本</param>
        /// <param name="parameters">sql语句对应参数</param>
        /// <returns>数据集DataSet对象</returns>
        public static DataSet GetDataSet(CommandType cmdType, string cmdText, params DbParameter[] parameters)
        {
            DataSet ds = new DataSet();
            DbCommand cmd = DbFactory.CreateDbCommand();
            DbConnection conn = DbFactory.CreateDbConnection(ConnectionString);
            try
            {
                PrepareCommand(cmd, conn, null, cmdType, cmdText, parameters);
                IDbDataAdapter sda = DbFactory.CreateDataAdapter(cmd);
                sda.Fill(ds);
                return ds;
            }
            catch (Exception ex)
            {
                conn.Close();
                cmd.Dispose();
                //log.Error(ex.Message);
                throw;
            }
        }
        /// <summary>
        /// 查询数据填充到数据集DataSet中
        /// </summary>
        /// <param name="cmdType">执行命令的类型（存储过程或T-SQL，等等）</param>
        /// <param name="cmdText">命令文本</param>
        /// <returns>数据集DataSet对象</returns>
        public static DataSet GetDataSet(CommandType cmdType, string cmdText)
        {
            DataSet ds = new DataSet();
            DbCommand cmd = DbFactory.CreateDbCommand();
            DbConnection conn = DbFactory.CreateDbConnection(ConnectionString);
            try
            {
                PrepareCommand(cmd, conn, null, cmdType, cmdText, null);
                IDbDataAdapter sda = DbFactory.CreateDataAdapter(cmd);
                sda.Fill(ds);
                return ds;
            }
            catch (Exception ex)
            {
                conn.Close();
                cmd.Dispose();
                //log.Error(ex.Message);
                throw;
            }
        }
        /// <summary>
        /// 依靠数据库连接字符串connectionString,
        /// 使用所提供参数，执行返回首行首列命令
        /// </summary>
        /// <param name="commandType">执行命令的类型（存储过程或T-SQL，等等）</param>
        /// <param name="commandText">存储过程名称或者T-SQL命令行</param>
        /// <param name="parameters">执行命令所需的sql语句对应参数</param>
        /// <returns>返回一个对象，使用Convert.To{Type}将该对象转换成想要的数据类型。</returns>
        public static object ExecuteScalar(CommandType cmdType, string cmdText, params DbParameter[] parameters)
        {
            try
            {
                DbCommand cmd = DbFactory.CreateDbCommand();
                using (DbConnection connection = DbFactory.CreateDbConnection(ConnectionString))
                {
                    PrepareCommand(cmd, connection, null, cmdType, cmdText, parameters);
                    object val = cmd.ExecuteScalar();
                    cmd.Parameters.Clear();
                    return val;
                }
            }
            catch (Exception ex)
            {
                //log.Error(ex.Message);
                throw;
            }
        }
        /// <summary>
        /// 依靠数据库连接字符串connectionString,
        /// 使用所提供参数，执行返回首行首列命令
        /// </summary>
        /// <param name="commandType">执行命令的类型（存储过程或T-SQL，等等）</param>
        /// <param name="commandText">存储过程名称或者T-SQL命令行</param>
        /// <returns>返回一个对象，使用Convert.To{Type}将该对象转换成想要的数据类型。</returns>
        public static object ExecuteScalar(CommandType cmdType, string cmdText)
        {
            try
            {
                DbCommand cmd = DbFactory.CreateDbCommand();
                using (DbConnection connection = DbFactory.CreateDbConnection(ConnectionString))
                {
                    PrepareCommand(cmd, connection, null, cmdType, cmdText, null);
                    object val = cmd.ExecuteScalar();
                    cmd.Parameters.Clear();
                    return val;
                }
            }
            catch (Exception ex)
            {
                //log.Error(ex.Message);
                throw;
            }
        }
        /// <summary>
        ///依靠数据库连接字符串connectionString,
        /// 使用所提供参数，执行返回首行首列命令
        /// </summary>
        /// <param name="connection">数据库连接对象</param>
        /// <param name="commandType">执行命令的类型（存储过程或T-SQL，等等）</param>
        /// <param name="commandText">存储过程名称或者T-SQL命令行</param>
        /// <param name="parameters">执行命令所需的sql语句对应参数</param>
        /// <returns>返回一个对象，使用Convert.To{Type}将该对象转换成想要的数据类型。</returns>
        public static object ExecuteScalar(DbConnection connection, CommandType cmdType, string cmdText, params DbParameter[] parameters)
        {
            try
            {
                DbCommand cmd = DbFactory.CreateDbCommand();
                PrepareCommand(cmd, connection, null, cmdType, cmdText, parameters);
                object val = cmd.ExecuteScalar();
                cmd.Parameters.Clear();
                return val;
            }
            catch (Exception ex)
            {
                //log.Error(ex.Message);
                throw;
            }
        }
        /// <summary>
        ///依靠数据库连接字符串connectionString,
        /// 使用所提供参数，执行返回首行首列命令
        /// </summary>
        /// <param name="connection">数据库连接对象</param>
        /// <param name="commandType">执行命令的类型（存储过程或T-SQL，等等）</param>
        /// <param name="commandText">存储过程名称或者T-SQL命令行</param>
        /// <param name="parameters">执行命令所需的sql语句对应参数</param>
        /// <returns>返回一个对象，使用Convert.To{Type}将该对象转换成想要的数据类型。</returns>
        public static object ExecuteScalar(DbConnection connection, CommandType cmdType, string cmdText)
        {
            try
            {
                DbCommand cmd = DbFactory.CreateDbCommand();
                PrepareCommand(cmd, connection, null, cmdType, cmdText, null);
                object val = cmd.ExecuteScalar();
                cmd.Parameters.Clear();
                return val;
            }
            catch (Exception ex)
            {
                //log.Error(ex.Message);
                throw;
            }
        }
        /// <summary>
        ///依靠数据库连接字符串connectionString,
        /// 使用所提供参数，执行返回首行首列命令
        /// </summary>
        /// <param name="connection">数据库连接对象</param>
        /// <param name="commandType">执行命令的类型（存储过程或T-SQL，等等）</param>
        /// <param name="commandText">存储过程名称或者T-SQL命令行</param>
        /// <param name="parameters">执行命令所需的sql语句对应参数</param>
        /// <returns>返回一个对象，使用Convert.To{Type}将该对象转换成想要的数据类型。</returns>
        public static object ExecuteScalar(DbConnection conn, DbTransaction isOpenTrans, CommandType cmdType, string cmdText)
        {
            try
            {
                DbCommand cmd = DbFactory.CreateDbCommand();
                PrepareCommand(cmd, conn, isOpenTrans, cmdType, cmdText, null);
                object val = cmd.ExecuteScalar();
                cmd.Parameters.Clear();
                return val;
            }
            catch (Exception ex)
            {
                //log.Error(ex.Message);
                throw;
            }
        }
        /// <summary>
        ///依靠数据库连接字符串connectionString,
        /// 使用所提供参数，执行返回首行首列命令
        /// </summary>
        /// <param name="isOpenTrans">事务</param>
        /// <param name="commandType">执行命令的类型（存储过程或T-SQL，等等）</param>
        /// <param name="commandText">存储过程名称或者T-SQL命令行</param>
        /// <param name="parameters">执行命令所需的sql语句对应参数</param>
        /// <returns>返回一个对象，使用Convert.To{Type}将该对象转换成想要的数据类型。</returns>
        public static object ExecuteScalar(DbTransaction isOpenTrans, CommandType cmdType, string cmdText, params DbParameter[] parameters)
        {
            try
            {
                DbCommand cmd = DbFactory.CreateDbCommand();
                PrepareCommand(cmd, isOpenTrans.Connection, isOpenTrans, cmdType, cmdText, parameters);
                object val = cmd.ExecuteScalar();
                cmd.Parameters.Clear();
                return val;
            }
            catch (Exception ex)
            {
                //log.Error(ex.Message);
                throw;
            }
        }
        /// <summary>
        /// 为即将执行准备一个命令
        /// </summary>
        /// <param name="cmd">SqlCommand对象</param>
        /// <param name="conn">SqlConnection对象</param>
        /// <param name="isOpenTrans">DbTransaction对象</param>
        /// <param name="cmdType">执行命令的类型（存储过程或T-SQL，等等）</param>
        /// <param name="cmdText">存储过程名称或者T-SQL命令行, e.g. Select * from Products</param>
        /// <param name="cmdParms">SqlParameters to use in the command</param>
        private static void PrepareCommand(DbCommand cmd, DbConnection conn, DbTransaction isOpenTrans, CommandType cmdType, string cmdText, DbParameter[] cmdParms)
        {
            if (conn.State != ConnectionState.Open)
                conn.Open();
            cmd.Connection = conn;
            cmd.CommandText = cmdText;
            if (isOpenTrans != null)
                cmd.Transaction = isOpenTrans;
            cmd.CommandType = cmdType;
            if (cmdParms != null)
            {
                cmd.Parameters.AddRange(cmdParms);
            }
        }
        /// <summary>
        /// 用于数据库类型的字符串枚举转换
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="value"></param>
        /// <returns></returns>
        public void DatabaseTypeEnumParse(string value)
        {
            try
            {
                switch (value)
                {
                    case "System.Data.SqlClient":
                        DbType = DatabaseType.SqlServer;
                        break;
                    case "System.Data.OracleClient":
                        DbType = DatabaseType.Oracle;
                        break;
                    case "MySql.Data.MySqlClient":
                        DbType = DatabaseType.MySql;
                        break;
                    case "System.Data.OleDb":
                        DbType = DatabaseType.Access;
                        break;
                    case "System.Data.SQLite":
                        DbType = DatabaseType.SQLite;
                        break;
                    default:
                        break;
                }
            }
            catch
            {
                throw new Exception("数据库类型\"" + value + "\"错误，请检查！");
            }
        }
    }
}