/*
 * Copyright 2002-2020 the original author or authors.
 *
 * Licensed 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
 *
 *      https://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.
 */

package org.springframework.transaction.annotation;

import java.io.Serializable;
import java.lang.reflect.AnnotatedElement;
import java.util.ArrayList;
import java.util.List;
import java.util.Set;

import org.springframework.core.annotation.AnnotatedElementUtils;
import org.springframework.core.annotation.AnnotationAttributes;
import org.springframework.core.annotation.AnnotationUtils;
import org.springframework.lang.Nullable;
import org.springframework.transaction.interceptor.NoRollbackRuleAttribute;
import org.springframework.transaction.interceptor.RollbackRuleAttribute;
import org.springframework.transaction.interceptor.RuleBasedTransactionAttribute;
import org.springframework.transaction.interceptor.TransactionAttribute;
import org.springframework.util.Assert;
import org.springframework.util.StringUtils;

/**
 * Strategy implementation for parsing Spring's {@link Transactional} annotation.
 *
 * @author Juergen Hoeller
 * @author Mark Paluch
 * @since 2.5
 */
@SuppressWarnings("serial")
public class SpringTransactionAnnotationParser implements TransactionAnnotationParser, Serializable {

	@Override
	public boolean isCandidateClass(Class<?> targetClass) {
		return AnnotationUtils.isCandidateClass(targetClass, Transactional.class);
	}

	@Override
	@Nullable
	public TransactionAttribute parseTransactionAnnotation(AnnotatedElement element) {
		AnnotationAttributes attributes = AnnotatedElementUtils.findMergedAnnotationAttributes(
				element, Transactional.class, false, false);
		if (attributes != null) {
			return parseTransactionAnnotation(attributes);
		}
		else {
			return null;
		}
	}

	public TransactionAttribute parseTransactionAnnotation(Transactional ann) {
		return parseTransactionAnnotation(AnnotationUtils.getAnnotationAttributes(ann, false, false));
	}

	protected TransactionAttribute parseTransactionAnnotation(AnnotationAttributes attributes) {
		RuleBasedTransactionAttribute rbta = new RuleBasedTransactionAttribute();

		Propagation propagation = attributes.getEnum("propagation");
		rbta.setPropagationBehavior(propagation.value());
		Isolation isolation = attributes.getEnum("isolation");
		rbta.setIsolationLevel(isolation.value());

		rbta.setTimeout(attributes.getNumber("timeout").intValue());
		String timeoutString = attributes.getString("timeoutString");
		Assert.isTrue(!StringUtils.hasText(timeoutString) || rbta.getTimeout() < 0,
				"Specify 'timeout' or 'timeoutString', not both");
		rbta.setTimeoutString(timeoutString);

		rbta.setReadOnly(attributes.getBoolean("readOnly"));
		rbta.setQualifier(attributes.getString("value"));
		rbta.setLabels(Set.of(attributes.getStringArray("label")));

		List<RollbackRuleAttribute> rollbackRules = new ArrayList<>();
		for (Class<?> rbRule : attributes.getClassArray("rollbackFor")) {
			rollbackRules.add(new RollbackRuleAttribute(rbRule));
		}
		for (String rbRule : attributes.getStringArray("rollbackForClassName")) {
			rollbackRules.add(new RollbackRuleAttribute(rbRule));
		}
		for (Class<?> rbRule : attributes.getClassArray("noRollbackFor")) {
			rollbackRules.add(new NoRollbackRuleAttribute(rbRule));
		}
		for (String rbRule : attributes.getStringArray("noRollbackForClassName")) {
			rollbackRules.add(new NoRollbackRuleAttribute(rbRule));
		}
		rbta.setRollbackRules(rollbackRules);

		return rbta;
	}


	@Override
	public boolean equals(@Nullable Object other) {
		return (other instanceof SpringTransactionAnnotationParser);
	}

	@Override
	public int hashCode() {
		return SpringTransactionAnnotationParser.class.hashCode();
	}

}
