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 *   Licensed to the Apache Software Foundation (ASF) under one
 *  or more contributor license agreements.  See the NOTICE file
 *  distributed with this work for additional information
 *  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
 *  with the License.  You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing,
 *  software distributed under the License is distributed on an
 *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 *  KIND, either express or implied.  See the License for the
 *  specific language governing permissions and limitations
 *  under the License.
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package org.apache.cayenne.tools;

import org.apache.cayenne.access.DbGenerator;
import org.apache.cayenne.datasource.DriverDataSource;
import org.apache.cayenne.dba.DbAdapter;
import org.apache.cayenne.dbsync.DbSyncModule;
import org.apache.cayenne.di.DIBootstrap;
import org.apache.cayenne.di.Injector;
import org.apache.cayenne.log.NoopJdbcEventLogger;
import org.apache.cayenne.map.DataMap;
import org.apache.cayenne.map.DbEntity;
import org.apache.cayenne.dbsync.reverse.configuration.ToolsModule;
import org.apache.cayenne.util.Util;
import org.slf4j.Logger;
import org.apache.tools.ant.BuildException;
import org.apache.tools.ant.Project;

import java.sql.Driver;
import java.util.Collections;

/**
 * An Ant Task that is a frontend to Cayenne DbGenerator allowing schema
 * generation from DataMap using Ant.
 * 
 * @since 1.2
 */
// TODO: support classpath attribute for loading the driver
public class DbGeneratorTask extends CayenneTask {

	// DbGenerator options... setup defaults similar to DbGenerator itself:
	// all DROP set to false, all CREATE - to true
	protected boolean dropTables;
	protected boolean dropPK;
	protected boolean createTables = true;
	protected boolean createPK = true;
	protected boolean createFK = true;

	@Override
	public void execute() {

		Logger logger = new AntLogger(this);

		log(String.format("connection settings - [driver: %s, url: %s, username: %s]", driver, url, userName),
				Project.MSG_VERBOSE);

		log(String.format(
				"generator options - [dropTables: %s, dropPK: %s, createTables: %s, createPK: %s, createFK: %s]",
				dropTables, dropPK, createTables, createPK, createFK), Project.MSG_VERBOSE);

		validateAttributes();

		ClassLoader loader = null;
		Injector injector = DIBootstrap.createInjector(new DbSyncModule(), new ToolsModule(logger));
		try {
			loader = Thread.currentThread().getContextClassLoader();
			Thread.currentThread().setContextClassLoader(DbGeneratorTask.class.getClassLoader());

			// Load the data map and run the db generator.
			DataMap dataMap = loadDataMap();

			// load driver taking custom CLASSPATH into account...
			DriverDataSource dataSource = new DriverDataSource((Driver) Class.forName(driver).newInstance(), url,
					userName, password);

			DbAdapter adapter = getAdapter(injector, dataSource);

			DbGenerator generator = new DbGenerator(adapter, dataMap, Collections.<DbEntity> emptyList(), null,
					NoopJdbcEventLogger.getInstance());
			generator.setShouldCreateFKConstraints(createFK);
			generator.setShouldCreatePKSupport(createPK);
			generator.setShouldCreateTables(createTables);
			generator.setShouldDropPKSupport(dropPK);
			generator.setShouldDropTables(dropTables);

			generator.runGenerator(dataSource);
		} catch (Exception ex) {
			Throwable th = Util.unwindException(ex);

			String message = "Error generating database";

			if (th.getLocalizedMessage() != null) {
				message += ": " + th.getLocalizedMessage();
			}

			log(message, Project.MSG_ERR);
			throw new BuildException(message, th);
		} finally {
			Thread.currentThread().setContextClassLoader(loader);
			injector.shutdown();
		}
	}

	/**
	 * Validates attributes that are not related to internal
	 * DefaultClassGenerator. Throws BuildException if attributes are invalid.
	 */
	protected void validateAttributes() throws BuildException {
		StringBuilder error = new StringBuilder("");

		if (map == null) {
			error.append("The 'map' attribute must be set.\n");
		}

		if (driver == null) {
			error.append("The 'driver' attribute must be set.\n");
		}

		if (url == null) {
			error.append("The 'adapter' attribute must be set.\n");
		}

		if (error.length() > 0) {
			throw new BuildException(error.toString());
		}
	}

	public void setCreateFK(boolean createFK) {
		this.createFK = createFK;
	}

	public void setCreatePK(boolean createPK) {
		this.createPK = createPK;
	}

	public void setCreateTables(boolean createTables) {
		this.createTables = createTables;
	}

	public void setDropPK(boolean dropPK) {
		this.dropPK = dropPK;
	}

	public void setDropTables(boolean dropTables) {
		this.dropTables = dropTables;
	}
}