/*
 * The contents of this file are subject to the terms
 * of the Common Development and Distribution License
 * (the "License").  You may not use this file except
 * in compliance with the License.
 *
 * You can obtain a copy of the license at
 * glassfish/bootstrap/legal/CDDLv1.0.txt or
 * https://glassfish.dev.java.net/public/CDDLv1.0.html .
 * See the License for the specific language governing
 * permissions and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL
 * HEADER in each file and include the License file at
 * glassfish/bootstrap/legal/CDDLv1.0.txt.  If applicable,
 * add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your
 * own identifying information: Portions Copyright [yyyy]
 * [name of copyright owner]
 */
// Copyright (c) 1998, 2006, Oracle. All rights reserved.
package oracle.toplink.essentials.platform.database;

import java.io.IOException;
import java.io.Writer;
import java.util.Hashtable;

import oracle.toplink.essentials.exceptions.ValidationException;
import oracle.toplink.essentials.expressions.ExpressionOperator;
import oracle.toplink.essentials.internal.databaseaccess.FieldTypeDefinition;
import oracle.toplink.essentials.queryframework.ValueReadQuery;

/**
 * This platform provides H2 specific behaviour.
 * To enable this platform change the following setting in persistence.xml:
 * <pre>
 * &lt;property
 *   name="toplink.target-database"
 *   value="oracle.toplink.essentials.platform.database.H2Platform"/>
 * </pre>
 * In old versions of Glassfish, the property name is
 * <code>toplink.platform.class.name</code>.
 * See also: https://glassfish.dev.java.net/issues/show_bug.cgi?id=4042
 *
 * @author Thomas Mueller
 * @author Marcio Borges (http://www.marciowb.net/blog/2008_08_01_)
 */
public class H2Platform extends DatabasePlatform {

    protected Hashtable buildFieldTypes() {
        Hashtable fieldTypeMapping;
        fieldTypeMapping = super.buildFieldTypes();
        fieldTypeMapping.put(Boolean.class, new FieldTypeDefinition("TINYINT", false));
        fieldTypeMapping.put(Integer.class, new FieldTypeDefinition("INTEGER", false));
        fieldTypeMapping.put(Long.class, new FieldTypeDefinition("NUMERIC", 19));
        fieldTypeMapping.put(Float.class, new FieldTypeDefinition("REAL", false));
        fieldTypeMapping.put(Double.class, new FieldTypeDefinition("REAL", false));
        fieldTypeMapping.put(Short.class, new FieldTypeDefinition("SMALLINT", false));
        fieldTypeMapping.put(Byte.class, new FieldTypeDefinition("SMALLINT", false));
        fieldTypeMapping.put(java.math.BigInteger.class, new FieldTypeDefinition("NUMERIC", 38));
        fieldTypeMapping.put(java.math.BigDecimal.class, new FieldTypeDefinition("NUMERIC", 38).setLimits(38, -19, 19));
        fieldTypeMapping.put(Number.class, new FieldTypeDefinition("NUMERIC", 38).setLimits(38, -19, 19));
        fieldTypeMapping.put(Byte[].class, new FieldTypeDefinition("BINARY", false));
        fieldTypeMapping.put(Character[].class, new FieldTypeDefinition("LONGVARCHAR", false));
        fieldTypeMapping.put(byte[].class, new FieldTypeDefinition("BINARY", false));
        fieldTypeMapping.put(char[].class, new FieldTypeDefinition("LONGVARCHAR", false));
        fieldTypeMapping.put(java.sql.Blob.class, new FieldTypeDefinition("BINARY", false));
        fieldTypeMapping.put(java.sql.Clob.class, new FieldTypeDefinition("LONGVARCHAR", false));
        fieldTypeMapping.put(java.sql.Date.class, new FieldTypeDefinition("DATE", false));
        fieldTypeMapping.put(java.sql.Time.class, new FieldTypeDefinition("TIME", false));
        fieldTypeMapping.put(java.sql.Timestamp.class, new FieldTypeDefinition("TIMESTAMP", false));
        return fieldTypeMapping;
    }

    public boolean isH2() {
        return true;
    }

    public boolean supportsForeignKeyConstraints() {
        return true;
    }

    public ValueReadQuery buildSelectQueryForNativeSequence(String seqName, Integer size) {
        StringBuffer buff = new StringBuffer();
        buff.append("SELECT MAX(NEXT VALUE FOR ");
        buff.append(getQualifiedSequenceName(seqName));
        buff.append(") FROM SYSTEM_RANGE(1, ");
        buff.append(size);
        buff.append(")");
        String sql = buff.toString();
        return new ValueReadQuery(sql);
    }

    public boolean supportsNativeSequenceNumbers() {
        return true;
    }

    protected String getQualifiedSequenceName(String seqName) {
        if (getTableQualifier().equals("")) {
            return seqName;
        }
        return getTableQualifier() + "." + seqName;
    }

    public boolean supportsSelectForUpdateNoWait() {
        return true;
    }

    protected ExpressionOperator todayOperator() {
        return ExpressionOperator.simpleFunctionNoParentheses(ExpressionOperator.Today, "SYSDATE");
    }

    protected void initializePlatformOperators() {
        super.initializePlatformOperators();
        addOperator(ExpressionOperator.simpleMath(ExpressionOperator.Concat, "||"));
    }

    public boolean shouldUseJDBCOuterJoinSyntax() {
        return false;
    }

    public boolean supportsSequenceObjects() {
        return true;
    }

    public boolean supportsIdentity() {
        return true;
    }

    public ValueReadQuery buildSelectQueryForIdentity() {
        return new ValueReadQuery("SELECT IDENTITY()");
    }

    public void printFieldIdentityClause(Writer writer) throws ValidationException {
        try {
            writer.write(" IDENTITY");
        } catch (final IOException ioException) {
            throw ValidationException.fileError(ioException);
        }
    }

}
