using System;
using System.Collections.Generic;
using System.IO;
using System.Text;
using System.Data.SqlClient;
using Mesnac.Codd.Session;
using System.Data.SQLite;

namespace Mesnac.Equip.FictitiousPlc
{
    public class DbHelperFactory
    {
        #region 单例模式
        private static DbHelperFactory _this;
        public static DbHelperFactory Instance
        {
            get
            {
                if (null == _this)
                    _this = new DbHelperFactory();
                return _this;
            }
        }
        private DbHelperFactory()
        {
        }
        #endregion
        private void CreatNullFile(string fileName)
        {
            FileInfo fi = new FileInfo(fileName);
            if (fi.Exists)
            {
                return;
            }
            FileStream fs = File.Create(fileName);
            fs.Close();
        }
        public DbHelper NewDbHelper(string fileName)
        {
            if (string.IsNullOrWhiteSpace(fileName))
            {
                string path = System.Diagnostics.Process.GetCurrentProcess().MainModule.FileName;
                path = new System.IO.FileInfo(path).Directory.FullName;
                fileName = System.IO.Path.Combine(path, "Plc.db");
            }
            CreatNullFile(fileName);
            string constr = "Data Source=" + fileName;
            DbSession dbsession = new DbSession(SQLiteFactory.Instance, constr);
            return new DbHelper(dbsession);
        }
        public DbHelper NewDbHelper()
        {
            return NewDbHelper(string.Empty);
        }
    }
}