using System;
using System.Text;

namespace CSFramework.DB
{
    /// <summary>
    /// 数据库对象工厂
    /// </summary>
    public static class DatabaseFactory
    {
        /// <summary>
        /// 执行SQL命令超时时间，单位：秒。当未设置此参数（默认0），DbCommand默认TimeOut值，30秒。
        /// </summary>
        public static int CommandTimeOut { get; set; } = 30;

        /// <summary>
        /// 连接数据库服务器超时时间，单位：秒。当未设置此参数（默认0），DbConnection默认TimeOut值，15秒。
        /// </summary>
        public static int ConnectionTimeOut { get; set; } = 15;

        /// <summary>
        /// 创建数据库（使用DataProviderFactory创建数据存取基础组件，通用版）
        /// </summary>
        /// <param name="providerType">数据库类型</param>
        /// <param name="connectionString">数据库连接字符串</param>
        /// <returns></returns>
        public static IDatabase CreateMDB(DatabaseType providerType,
            string connectionString)
        {
            SetTimeOut(ref connectionString, ConnectionTimeOut);
            return new DatabaseMDB(providerType, connectionString);
        }

        /// <summary>
        /// 创建SQL Server数据库
        /// </summary>
        /// <param name="connectionString">数据库连接字符串</param>
        /// <returns></returns>
        public static IDatabase CreateSqlDatabase(string connectionString)
        {
            SetTimeOut(ref connectionString, ConnectionTimeOut);
            return new DatabaseMSSQL(connectionString);
        }

        /// <summary>
        /// 创建MySQL数据库
        /// </summary>
        /// <param name="connectionString">数据库连接字符串</param>
        /// <returns></returns>
        public static IDatabase CreateMySqlDatabase(string connectionString)
        {
            SetTimeOut(ref connectionString, ConnectionTimeOut);
            return new DatabaseMySQL(connectionString);
        }

        /// <summary>
        /// 创建Oracle数据库
        /// </summary>
        /// <param name="connectionString">数据库连接字符串</param>
        /// <returns></returns>
        public static IDatabase CreateOracleDatabase(string connectionString)
        {
            return new DatabaseOracle(connectionString);
        }

        /// <summary>
        /// 创建数据库
        /// </summary>
        /// <param name="dbType">数据库类型</param>
        /// <param name="connectionString">数据库连接字符串</param>
        /// <returns></returns>
        public static IDatabase CreateDatabase(DatabaseType dbType,
            string connectionString)
        {
            if (dbType == DatabaseType.SqlServer)
            {
                SetTimeOut(ref connectionString, ConnectionTimeOut);
                return new DatabaseMSSQL(connectionString);
            }

            if (dbType == DatabaseType.MySQL)
            {
                SetTimeOut(ref connectionString, ConnectionTimeOut);
                return new DatabaseMySQL(connectionString);
            }

            if (dbType == DatabaseType.Oracle)
                return new DatabaseOracle(connectionString);

            throw new Exception("未支持的数据库类型！");
        }

        /// <summary>
        /// 创建数据库
        /// </summary>
        /// <param name="dbType">数据库类型</param>
        /// <param name="connectionString">数据库连接字符串</param>
        /// <returns></returns>
        public static IDatabase CreateDatabase(string dbType,
            string connectionString)
        {
            SetTimeOut(ref connectionString, ConnectionTimeOut);
            DatabaseType databaseType;
            if (!Enum.TryParse<DatabaseType>(dbType, true, out databaseType))
                throw new Exception("不支持的数据库类型！");

            if (databaseType == DatabaseType.SqlServer)
                return new DatabaseMSSQL(connectionString);
            if (databaseType == DatabaseType.MySQL)
                return new DatabaseMySQL(connectionString);
            if (databaseType == DatabaseType.Oracle)
                return new DatabaseOracle(connectionString);
            throw new Exception("未支持的数据库类型！");
        }

        /// <summary>
        /// ADO组件工厂
        /// </summary>
        /// <param name="dbType">数据库类型</param>
        /// <param name="connectionString">数据连接字符串</param>
        /// <returns></returns>
        public static IAdoFactory GetADOFactory(DatabaseType dbType,
            string connectionString)
        {
            SetTimeOut(ref connectionString, ConnectionTimeOut);
            return CreateDatabase(dbType, connectionString);
        }

        /// <summary> 
        /// 更改连接字符串的超时时间(适用MsSQL,MySQL) 
        /// </summary> 
        /// <param name="sConn">连接字符串</param> 
        /// <param name="TIME_OUT">超时时间,秒</param> 
        internal static void SetTimeOut(ref string sConn, int TIME_OUT)
        {
            //连接字符串没有定义Connection TimeOut
            if (sConn.ToLower().IndexOf("Connection TimeOut".ToLower(), 0) <= 0)
            {
                sConn = sConn + ";Connection TimeOut=" + TIME_OUT.ToString() +
                        ";";
            }
            else
            {
                //分隔
                var items = sConn.Split(new char[] { ';' },
                    StringSplitOptions.RemoveEmptyEntries);
                //string item = items.Where(e => e.ToLower().IndexOf("Connection TimeOut".ToLower(), 0) >= 0).FirstOrDefault();

                for (var i = 0; i <= items.Length - 1; i++)
                {
                    var s = items[i];
                    //;Connection TimeOut={4}; 
                    if (s.ToLower()
                            .IndexOf("Connection TimeOut".ToLower(), 0) >= 0)
                    {
                        var t = s.Split('=');
                        items[i] = "Connection TimeOut=" + TIME_OUT.ToString();
                    }
                }

                var sb = new StringBuilder();
                foreach (var s in items) sb.Append(s + ";");
                sConn = sb.ToString();
            }
        }
    }
}