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 *  regarding copyright ownership.  The ASF licenses this file
 *  to you under the Apache License, Version 2.0 (the
 *  "License"); you may not use this file except in compliance
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 *  Unless required by applicable law or agreed to in writing,
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package org.apache.cayenne.dba.frontbase;

import java.sql.Types;
import java.util.Collection;
import java.util.Collections;
import java.util.Iterator;

import org.apache.cayenne.CayenneRuntimeException;
import org.apache.cayenne.access.DataNode;
import org.apache.cayenne.access.types.ExtendedTypeMap;
import org.apache.cayenne.dba.JdbcAdapter;
import org.apache.cayenne.dba.PkGenerator;
import org.apache.cayenne.dba.TypesMapping;
import org.apache.cayenne.map.DbAttribute;
import org.apache.cayenne.map.DbEntity;
import org.apache.cayenne.query.Query;
import org.apache.cayenne.query.SQLAction;

/**
 * DbAdapter implementation for <a href="http://www.frontbase.com/">FrontBase RDBMS</a>.
 * Sample connection settings to use with FrontBase are shown below:
 * 
 * <pre>
 *          fb.cayenne.adapter = org.apache.cayenne.dba.frontbase.FrontBaseAdapter
 *          fb.jdbc.username = _system
 *          fb.jdbc.password = secret
 *          fb.jdbc.url = jdbc:FrontBase://localhost/cayenne/
 *          fb.jdbc.driver = jdbc.FrontBase.FBJDriver
 * </pre>
 * 
 * @since 1.2
 */
// TODO, Andrus 11/8/2005:
// Limitations (also see FrontBaseStackAdapter in unit tests):
//
// 1. Case insensitive ordering (i.e. UPPER in the ORDER BY clause) is supported by
// FrontBase, however aliases don't work ( ORDER BY UPPER(t0.ARTIST_NAME)) ... not sure
// what to do about it.
public class FrontBaseAdapter extends JdbcAdapter {

    public FrontBaseAdapter() {
        setSupportsBatchUpdates(true);
    }

    /**
     * Uses special action builder to create the right action.
     */
    @Override
    public SQLAction getAction(Query query, DataNode node) {
        return query.createSQLAction(new FrontBaseActionBuilder(this, node
                .getEntityResolver()));
    }

    @Override
    public String tableTypeForTable() {
        return "BASE TABLE";
    }

    @Override
    protected void configureExtendedTypes(ExtendedTypeMap map) {
        super.configureExtendedTypes(map);

        map.registerType(new FrontBaseByteArrayType());
        map.registerType(new FrontBaseBooleanType());
        map.registerType(new FrontBaseCharType());
    }

    /**
     * Customizes table creating procedure for FrontBase.
     */
    @Override
    public String createTable(DbEntity ent) {

        StringBuilder buf = new StringBuilder();
        buf.append("CREATE TABLE ").append(ent.getFullyQualifiedName()).append(" (");

        // columns
        Iterator<DbAttribute> it = ent.getAttributes().iterator();
        boolean first = true;
        while (it.hasNext()) {
            if (first)
                first = false;
            else
                buf.append(", ");

            DbAttribute at = it.next();

            // attribute may not be fully valid, do a simple check
            if (at.getType() == TypesMapping.NOT_DEFINED) {
                throw new CayenneRuntimeException("Undefined type for attribute '"
                        + ent.getFullyQualifiedName()
                        + "."
                        + at.getName()
                        + "'.");
            }

            String[] types = externalTypesForJdbcType(at.getType());
            if (types == null || types.length == 0) {
                throw new CayenneRuntimeException("Undefined type for attribute '"
                        + ent.getFullyQualifiedName()
                        + "."
                        + at.getName()
                        + "': "
                        + at.getType());
            }

            String type = types[0];
            buf.append(at.getName()).append(' ').append(type);

            // Mapping LONGVARCHAR without length creates a column with lenght "1" which
            // is defintely not what we want...so just use something very large (1Gb seems
            // to be the limit for FB)
            if (at.getType() == Types.LONGVARCHAR) {

                int len = at.getMaxLength() > 0 ? at.getMaxLength() : 1073741824;
                buf.append("(").append(len).append(")");
            }
            else if (at.getType() == Types.VARBINARY || at.getType() == Types.BINARY) {

                // use a BIT column with size * 8
                int len = at.getMaxLength() > 0 ? at.getMaxLength() : 1073741824;
                len *= 8;
                buf.append("(").append(len).append(")");
            }
            else if (TypesMapping.supportsLength(at.getType())) {
                int len = at.getMaxLength();
                int scale = TypesMapping.isDecimal(at.getType()) ? at.getScale() : -1;

                // sanity check
                if (scale > len) {
                    scale = -1;
                }

                if (len > 0) {
                    buf.append('(').append(len);

                    if (scale >= 0) {
                        buf.append(", ").append(scale);
                    }

                    buf.append(')');
                }
            }

            if (at.isMandatory()) {
                buf.append(" NOT NULL");
            }
            // else: don't appen NULL for FrontBase:
        }

        // primary key clause
        Iterator<DbAttribute> pkit = ent.getPrimaryKeys().iterator();
        if (pkit.hasNext()) {
            if (first)
                first = false;
            else
                buf.append(", ");

            buf.append("PRIMARY KEY (");
            boolean firstPk = true;
            while (pkit.hasNext()) {
                if (firstPk)
                    firstPk = false;
                else
                    buf.append(", ");

                DbAttribute at = pkit.next();
                buf.append(at.getName());
            }
            buf.append(')');
        }
        buf.append(')');
        return buf.toString();
    }

    /**
     * Adds the CASCADE option to the DROP TABLE clause.
     */
    @Override
    public Collection<String> dropTableStatements(DbEntity table) {
        return Collections.singleton("DROP TABLE "
                + table.getFullyQualifiedName()
                + " CASCADE");
    }

    @Override
    protected PkGenerator createPkGenerator() {
        return new FrontBasePkGenerator();
    }
}
