/*
 * Hibernate, Relational Persistence for Idiomatic Java
 *
 * Copyright (c) 2010 by Red Hat Inc and/or its affiliates or by
 * third-party contributors as indicated by either @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.metamodel.relational;

import org.hibernate.dialect.Dialect;

/**
 * Models a table's primary key.
 * <p/>
 * NOTE : This need not be a physical primary key; we just mean a column or columns which uniquely identify rows in
 * the table.  Of course it is recommended to define proper integrity constraints, including primary keys.
 *
 * @author Gavin King
 * @author Steve Ebersole
 */
public class PrimaryKey extends AbstractConstraint implements Constraint, Exportable {
	// IMPL NOTE : I override the name behavior here because:
	//		(1) primary keys are not required to be named.
	//		(2) because a primary key is required for each table, it is easier to allow setting the constraint name
	// 			later in terms of building the metamodel
	//
	// todo : default name?  {TABLE_NAME}_PK maybe?
	private String name;

	protected PrimaryKey(TableSpecification table) {
		super( table, null );
	}

	@Override
	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

	@Override
	public String getExportIdentifier() {
		return getTable().getLoggableValueQualifier() + ".PK";
	}

	public String sqlConstraintStringInCreateTable(Dialect dialect) {
		StringBuilder buf = new StringBuilder("primary key (");
		boolean first = true;
		for ( Column column : getColumns() ) {
			if ( first ) {
				first = false;
			}
			else {
				buf.append(", ");
			}
			buf.append( column.getColumnName().encloseInQuotesIfQuoted( dialect ) );
		}
		return buf.append(')').toString();
	}

	public String sqlConstraintStringInAlterTable(Dialect dialect) {
		StringBuilder buf = new StringBuilder(
			dialect.getAddPrimaryKeyConstraintString( getName() )
		).append('(');
		boolean first = true;
		for ( Column column : getColumns() ) {
			if ( first ) {
				first = false;
			}
			else {
				buf.append(", ");
			}
			buf.append( column.getColumnName().encloseInQuotesIfQuoted( dialect ) );
		}
		return buf.append(')').toString();
	}

}