/*
 * Hibernate, Relational Persistence for Idiomatic Java
 *
 * Copyright (c) 2010, Red Hat Inc. or third-party contributors as
 * indicated by the @author tags or express copyright attribution
 * statements applied by the authors.  All third-party contributions are
 * distributed under license by Red Hat Inc.
 *
 * This copyrighted material is made available to anyone wishing to use, modify,
 * copy, or redistribute it subject to the terms and conditions of the GNU
 * Lesser General Public License, as published by the Free Software Foundation.
 *
 * This program 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 Lesser General Public License
 * for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this distribution; if not, write to:
 * Free Software Foundation, Inc.
 * 51 Franklin Street, Fifth Floor
 * Boston, MA  02110-1301  USA
 */
package org.hibernate.dialect;

import java.sql.CallableStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Types;

import org.hibernate.LockMode;
import org.hibernate.LockOptions;
//import org.hibernate.cfg.Environment;
//import org.hibernate.type.StandardBasicTypes;

/**
 * An abstract base class for Sybase and MS SQL Server dialects.
 *
 * @author Gavin King
 */
abstract class AbstractTransactSQLDialect extends Dialect {
	public AbstractTransactSQLDialect() {
		super();
		registerColumnType( Types.BINARY, "binary($l)" );
		registerColumnType( Types.BIT, "tinyint" );
		registerColumnType( Types.BIGINT, "numeric(19,0)" );
		registerColumnType( Types.SMALLINT, "smallint" );
		registerColumnType( Types.TINYINT, "smallint" );
		registerColumnType( Types.INTEGER, "int" );
		registerColumnType( Types.CHAR, "char(1)" );
		registerColumnType( Types.VARCHAR, "varchar($l)" );
		registerColumnType( Types.FLOAT, "float" );
		registerColumnType( Types.DOUBLE, "double precision" );
		registerColumnType( Types.DATE, "datetime" );
		registerColumnType( Types.TIME, "datetime" );
		registerColumnType( Types.TIMESTAMP, "datetime" );
		registerColumnType( Types.VARBINARY, "varbinary($l)" );
		registerColumnType( Types.NUMERIC, "numeric($p,$s)" );
		registerColumnType( Types.BLOB, "image" );
		registerColumnType( Types.CLOB, "text" );

//		getDefaultProperties().setProperty( Environment.STATEMENT_BATCH_SIZE, NO_BATCH );
	}

	@Override
	public String getAddColumnString() {
		return "add";
	}

	@Override
	public String getNullColumnString() {
		return "";
	}

	@Override
	public boolean qualifyIndexName() {
		return false;
	}

	@Override
	public String getForUpdateString() {
		return "";
	}

	@Override
	public boolean supportsIdentityColumns() {
		return true;
	}

	@Override
	public String getIdentitySelectString() {
		return "select @@identity";
	}

	@Override
	public String getIdentityColumnString() {
		//starts with 1, implicitly
		return "identity not null";
	}

	@Override
	public boolean supportsInsertSelectIdentity() {
		return true;
	}

	@Override
	public String appendIdentitySelectToInsert(String insertSQL) {
		return insertSQL + "\nselect @@identity";
	}

	@Override
	public String appendLockHint(LockOptions lockOptions, String tableName) {
		return lockOptions.getLockMode().greaterThan( LockMode.READ ) ? tableName + " holdlock" : tableName;
	}
//
//	@Override
//	public String applyLocksToSql(String sql, LockOptions aliasedLockOptions, Map<String, String[]> keyColumnNames) {
//		// TODO:  merge additional lockoptions support in Dialect.applyLocksToSql
//		final Iterator itr = aliasedLockOptions.getAliasLockIterator();
//		final StringBuilder buffer = new StringBuilder( sql );
//		int correction = 0;
//		while ( itr.hasNext() ) {
//			final Map.Entry entry = (Map.Entry) itr.next();
//			final LockMode lockMode = (LockMode) entry.getValue();
//			if ( lockMode.greaterThan( LockMode.READ ) ) {
//				final String alias = (String) entry.getKey();
//				int start = -1;
//				int end = -1;
//				if ( sql.endsWith( " " + alias ) ) {
//					start = ( sql.length() - alias.length() ) + correction;
//					end = start + alias.length();
//				}
//				else {
//					int position = sql.indexOf( " " + alias + " " );
//					if ( position <= -1 ) {
//						position = sql.indexOf( " " + alias + "," );
//					}
//					if ( position > -1 ) {
//						start = position + correction + 1;
//						end = start + alias.length();
//					}
//				}
//
//				if ( start > -1 ) {
//					final String lockHint = appendLockHint( lockMode, alias );
//					buffer.replace( start, end, lockHint );
//					correction += ( lockHint.length() - alias.length() );
//				}
//			}
//		}
//		return buffer.toString();
//	}

	@Override
	public int registerResultSetOutParameter(CallableStatement statement, int col) throws SQLException {
		// sql server just returns automatically
		return col;
	}

	@Override
	public ResultSet getResultSet(CallableStatement ps) throws SQLException {
		boolean isResultSet = ps.execute();
		// This assumes you will want to ignore any update counts
		while ( !isResultSet && ps.getUpdateCount() != -1 ) {
			isResultSet = ps.getMoreResults();
		}

		// You may still have other ResultSets or update counts left to process here
		// but you can't do it now or the ResultSet you just got will be closed
		return ps.getResultSet();
	}

	@Override
	public boolean supportsCurrentTimestampSelection() {
		return true;
	}

	@Override
	public boolean isCurrentTimestampSelectStringCallable() {
		return false;
	}

	@Override
	public String getCurrentTimestampSelectString() {
		return "select getdate()";
	}

	@Override
	public boolean supportsTemporaryTables() {
		return true;
	}

	@Override
	public String generateTemporaryTableName(String baseTableName) {
		return "#" + baseTableName;
	}

	@Override
	public boolean dropTemporaryTableAfterUse() {
		// sql-server, at least needed this dropped after use; strange!
		return true;
	}

	@Override
	public String getSelectGUIDString() {
		return "select newid()";
	}

	// Overridden informational metadata ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

	@Override
	public boolean supportsEmptyInList() {
		return false;
	}

	@Override
	public boolean supportsUnionAll() {
		return true;
	}

	@Override
	public boolean supportsExistsInSelect() {
		return false;
	}

	@Override
	public boolean doesReadCommittedCauseWritersToBlockReaders() {
		return true;
	}

	@Override
	public boolean doesRepeatableReadCauseReadersToBlockWriters() {
		return true;
	}

	@Override
	public boolean supportsTupleDistinctCounts() {
		return false;
	}
	
	@Override
	public boolean supportsTuplesInSubqueries() {
		return false;
	}
}