// Copyright (c) 2003-present, Jodd Team (http://jodd.org)
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice,
// this list of conditions and the following disclaimer.
//
// 2. Redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.

package jodd.db.oom;

import jodd.db.oom.meta.DbTable;
import jodd.io.findfile.ClassScanner;
import jodd.util.Consumers;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.util.function.Consumer;

/**
 * Auto-magically scans classpath for domain objects annotated with DbOom annotations.
 */
public class AutomagicDbOomConfigurator {

	private static final Logger log = LoggerFactory.getLogger(AutomagicDbOomConfigurator.class);

	protected final static byte[] DB_TABLE_ANNOTATION_BYTES = ClassScanner.bytecodeSignatureOfType(DbTable.class);
	protected final boolean registerAsEntities;
	protected final DbEntityManager dbEntityManager;
	private final Consumers<ClassScanner> classScannerConsumers = new Consumers<>();

	public AutomagicDbOomConfigurator(final DbEntityManager dbEntityManager, final boolean registerAsEntities) {
		this.dbEntityManager = dbEntityManager;
		this.registerAsEntities = registerAsEntities;
	}

	public AutomagicDbOomConfigurator withScanner(final Consumer<ClassScanner> scannerConsumer) {
		classScannerConsumers.add(scannerConsumer);
		return this;
	}


	/**
	 * Configures {@link DbEntityManager} with specified class path.
	 */
	public void configure() {
		long elapsed = System.currentTimeMillis();

		final ClassScanner classScanner = new ClassScanner();

		classScanner.detectEntriesMode(true);
		classScanner.scanDefaultClasspath();

		classScannerConsumers.accept(classScanner);

		registerAsConsumer(classScanner);

		try {
			classScanner.start();
		} catch (final Exception ex) {
			throw new DbOomException("Scan classpath error", ex);
		}
		elapsed = System.currentTimeMillis() - elapsed;
		if (log.isInfoEnabled()) {
			log.info("DbEntityManager configured in " + elapsed + "ms. Total entities: " + dbEntityManager.getTotalNames());
		}
	}

	/**
	 * Registers a class consumer that registers only those annotated with {@link DbTable}.
	 * Because of performance purposes, classes are not dynamically loaded; instead, their
	 * file content is examined.
	 */
	public void registerAsConsumer(final ClassScanner classScanner) {
		classScanner.registerEntryConsumer(classPathEntry -> {
			if (!classPathEntry.isTypeSignatureInUse(DB_TABLE_ANNOTATION_BYTES)) {
				return;
			}

			final Class<?> beanClass;
			try {
				beanClass = classPathEntry.loadClass();
			} catch (final ClassNotFoundException cnfex) {
				throw new DbOomException("Entry class not found: " + classPathEntry.name(), cnfex);
			}

			if (beanClass == null) {
				return;
			}

			final DbTable dbTable = beanClass.getAnnotation(DbTable.class);

			if (dbTable == null) {
				return;
			}

			if (registerAsEntities) {
				dbEntityManager.registerEntity(beanClass);
			} else {
				dbEntityManager.registerType(beanClass);
			}
		});
	}

}
