/*-
 * ============LICENSE_START=======================================================
 * ONAP - SO
 * ================================================================================
 * Copyright (C) 2018 AT&T Intellectual Property. All rights reserved.
 * ================================================================================
 * 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
 * 
 *      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.
 * ============LICENSE_END=========================================================
 */

package org.openecomp.mso.openpojo.rules;

import static org.hamcrest.CoreMatchers.anyOf;
import static org.hamcrest.CoreMatchers.anything;

import java.lang.reflect.Method;
import java.lang.reflect.Parameter;

import org.hamcrest.Matcher;

import com.openpojo.reflection.PojoClass;
import com.openpojo.validation.affirm.Affirm;
import com.openpojo.validation.rule.Rule;

/**
 * This rule ensures that classes have overriden the default equals and hashCode methods from Object
 */
public class HasEqualsAndHashCodeRule implements Rule {

	private final Matcher m;
	public HasEqualsAndHashCodeRule() {
		m = anything();
	}
	
	public HasEqualsAndHashCodeRule(Matcher m) {
		this.m = m;
	}
	@Override
	public void evaluate(PojoClass pojoClass) {
		Class<?> clazz = pojoClass.getClazz();
		if (anyOf(m).matches(clazz)) { 
			boolean hasEquals = false;
			boolean hasHashCode = false;
			final String name = clazz.getSimpleName();
			final Method[] methods;
			if (clazz.getSuperclass().equals(Object.class)) {
				methods = clazz.getDeclaredMethods();
			} else {
				methods = clazz.getMethods();
			}
			for (Method method : methods) {
				Parameter[] parameters = method.getParameters();
				if ("equals".equals(method.getName()) && boolean.class.equals(method.getReturnType()) && parameters.length == 1 && Object.class.equals(parameters[0].getType())) {
					hasEquals = true;
				} else if ("hashCode".equals(method.getName()) && int.class.equals(method.getReturnType())) {
					hasHashCode = true;
				}
			}
			
			if (!hasEquals) {
				Affirm.fail(String.format(
						"[%s] does not override equals", name));
			}
			if (!hasHashCode) {
				Affirm.fail(String.format(
						"[%s] does not override hashCode", name));
			}
		}
	}

}