/GenericConnector/GenConnection.cs

/*

* Copyright (c) 2010 Dennis Mackay-Fisher

*

* This file is part of PV Scheduler

* 

* PV Scheduler is free software: you can redistribute it and/or 

* modify it under the terms of the GNU General Public License version 3 or later 

* as published by the Free Software Foundation.

* 

* PV Scheduler is distributed in the hope that it will be useful,

* but WITHOUT ANY WARRANTY; without even the implied warranty of

* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

* GNU General Public License for more details.

* 

* You should have received a copy of the GNU General Public License

* along with PV Scheduler.

* If not, see <http://www.gnu.org/licenses/>.

*/



using System;

using System.Data;

using System.Data.Common;

using System.Data.OleDb;

using System.Collections.Generic;

using System.Linq;

using System.Text;



namespace GenericConnector

{

    public class GenConnection : DbConnection

    {

        private static int NextId = 0;



        public int Id

        {

            get;

            private set;

        }



        public int CreationThread

        {

            get;

            private set;

        }



        public DateTime CreationTime

        {

            get;

            private set;

        }



        protected DbConnection DbConnection;



        // SQLite works best when all SQL uses the same connection

        // This avoids Database is Locked error messages

        // GenDatabase creates a single Global connection for SQLite use

        private bool IsGlobal;



        public GenDatabase GenDatabase

        {

            get;

            private set;

        }



        internal GenConnection(GenDatabase db, bool isGlobal = false)

        {

            DbConnection = db.DbProviderFactory.CreateConnection();

            DbConnection.ConnectionString = db.ConnectionString;

            GenDatabase = db;

            IsGlobal = isGlobal;

            Id = NextId++;

            CreationThread = System.Threading.Thread.CurrentThread.ManagedThreadId;

            CreationTime = DateTime.Now;

        }



        protected override bool CanRaiseEvents

        {

            get

            {

                // the following is a guess as I cannot find any info on the MySql 

                // implementation of this protected member

                return true;

            }

        }



        public GenDBType DBType

        {

            get

            {

                return GenDatabase.GenDBType;

            }

        }



        public override int ConnectionTimeout

        {

            get

            {

                return DbConnection.ConnectionTimeout;

            }

        }



        public override string ConnectionString

        {

            get

            {

                throw new NotImplementedException();

            }

            set

            {

                throw new NotImplementedException();

            }

        }



        public override string Database

        {

            get { throw new NotImplementedException(); }

        }



        public override string DataSource

        {

            get { throw new NotImplementedException(); }

        }



        protected override DbProviderFactory DbProviderFactory

        {

            get

            {

                return base.DbProviderFactory;

            }

        }



        public DbConnection InnerConnection

        {

            get

            {

                return DbConnection;

            }

        }



        public override string ServerVersion

        {

            get { throw new NotImplementedException(); }

        }



        public override System.Data.ConnectionState State

        {

            get { throw new NotImplementedException(); }

        }



        protected override DbTransaction BeginDbTransaction(System.Data.IsolationLevel isolationLevel)

        {

            return DbConnection.BeginTransaction(isolationLevel);

        }



        public new DbTransaction BeginTransaction(System.Data.IsolationLevel isolationLevel)

        {

            return DbConnection.BeginTransaction(isolationLevel);

        }



        public new DbTransaction BeginTransaction()

        {

            return DbConnection.BeginTransaction();

        }



        public override void ChangeDatabase(string databaseName)

        {

            DbConnection.ChangeDatabase(databaseName);

        }



        public override void Close()

        {

            if (!IsGlobal)

            {

                DbConnection.Close();

                GenDatabase.ConnectionClosed(this);

            }

        }



        public new void Dispose()

        {

            if (!IsGlobal)

            {

                DbConnection.Dispose();

                base.Dispose();

            }

        }



        protected override DbCommand CreateDbCommand()

        {

            return DbConnection.CreateCommand();

        }



        public override void Open()

        {

            try

            {

                DbConnection.Open();

            }

            catch (Exception e)

            {

                throw new GenException(GenExceptionType.CannotConnectToDatabase, "GenConnection.Open: Error connecting to the database: " + e.Message, e);

            }

        }



        public override DataTable GetSchema()

        {

            return DbConnection.GetSchema();

        }



        public override DataTable GetSchema(String collectionName)

        {

            return DbConnection.GetSchema(collectionName);

        }



        public override DataTable GetSchema(String collectionName, String[] restrictionValues)

        {

            return DbConnection.GetSchema(collectionName, restrictionValues);

        }



        public DataRow GetSchemaTable(String tableName)

        {

            DataTable tableList;

            tableList = GetSchema();

            tableList = GetSchema("Tables");



            foreach (DataRow table in tableList.Rows)

            {

                if (table.ToString() == tableName)

                    return table;

            }

            return null;

        }



        /*

        private DataRow GetSchemaColumn(String tableName)

        {

            DataRow table = GetSchemaTable(tableName);

            if (table == null)

                return null;



            foreach (DataRow column in table.Columns)

            {

                if (table.ToString() == tableName)

                    return table;

            }

            return null;

        }

        */

        public bool SchemaHasTable(String tableName)

        {

            DataRow table = GetSchemaTable(tableName);

            return table != null;

        }

    }

}