/*
 * ********************************************************************
 *  Copyright (c) 2019 Contributors to the Eclipse Foundation
 *
 *  See the NOTICES file(s) distributed with this work for additional
 *  information regarding copyright ownership.
 *
 *  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.
 *
 *  SPDX-License-Identifier: Apache-2.0
 * ********************************************************************
 *
 */
package org.eclipse.microprofile.metrics.tck.metrics;

import static org.hamcrest.Matchers.equalTo;
import static org.hamcrest.Matchers.everyItem;
import static org.hamcrest.Matchers.is;
import static org.junit.Assert.assertThat;

import java.util.HashSet;
import java.util.Set;
import java.util.concurrent.atomic.AtomicLong;

import javax.inject.Inject;

import org.eclipse.microprofile.metrics.Metric;
import org.eclipse.microprofile.metrics.MetricID;
import org.eclipse.microprofile.metrics.MetricFilter;
import org.eclipse.microprofile.metrics.MetricRegistry;
import org.eclipse.microprofile.metrics.SimpleTimer;
import org.eclipse.microprofile.metrics.tck.util.MetricsUtil;
import org.hamcrest.Matchers;
import org.jboss.arquillian.container.test.api.Deployment;
import org.jboss.arquillian.junit.Arquillian;
import org.jboss.arquillian.junit.InSequence;
import org.jboss.shrinkwrap.api.Archive;
import org.jboss.shrinkwrap.api.ShrinkWrap;
import org.jboss.shrinkwrap.api.asset.EmptyAsset;
import org.jboss.shrinkwrap.api.spec.WebArchive;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;

@RunWith(Arquillian.class)
public class SimplyTimedClassBeanTest {

    private static final String CONSTRUCTOR_NAME = "SimplyTimedClassBean";

    private static final String CONSTRUCTOR_SIMPLE_TIMER_NAME = MetricsUtil.absoluteMetricName(SimplyTimedClassBean.class,
            "simplyTimedClass", CONSTRUCTOR_NAME);

    private static MetricID constructorMID;

    private static final String[] METHOD_NAMES = { "simplyTimedMethodOne", "simplyTimedMethodTwo", "simplyTimedMethodProtected",
            "simplyTimedMethodPackagedPrivate" };

    private static final Set<String> METHOD_SIMPLE_TIMER_NAMES = MetricsUtil.absoluteMetricNames(SimplyTimedClassBean.class,
            "simplyTimedClass", METHOD_NAMES);

    private static final MetricFilter METHOD_SIMPLE_TIMERS = new MetricFilter() {
        @Override
        public boolean matches(MetricID metricID, Metric metric) {
            return METHOD_SIMPLE_TIMER_NAMES.contains(metricID.getName());
        }
    };

    private static final Set<String> SIMPLE_TIMER_NAMES = MetricsUtil.absoluteMetricNames(SimplyTimedClassBean.class,
            "simplyTimedClass", METHOD_NAMES, CONSTRUCTOR_NAME);
            
    private static Set<MetricID> simpleTimerMIDs;

    // toString is overridden just to be able to trigger instantiation of the bean by calling it
    // it's otherwise irrelevant to the test, but it will also get a metric for itself
    private static Set<MetricID> simpleTimerMIDsIncludingToString;

    private static final AtomicLong METHOD_COUNT = new AtomicLong();

    @Deployment
    static Archive<?> createTestArchive() {
        return ShrinkWrap.create(WebArchive.class)
                // Test bean
                .addClasses(SimplyTimedClassBean.class, MetricsUtil.class)
                // Bean archive deployment descriptor
                .addAsWebInfResource(EmptyAsset.INSTANCE, "beans.xml");
    }

    @Inject
    private MetricRegistry registry;

    @Inject
    private SimplyTimedClassBean bean;

    @Before
    public void instantiateApplicationScopedBean() {
        // Let's trigger the instantiation of the application scoped bean
        // explicitly
        // as only a proxy gets injected otherwise
        bean.toString();
        /*
         * The MetricID relies on the MicroProfile Config API.
         * Running a managed arquillian container will result
         * with the MetricID being created in a client process
         * that does not contain the MPConfig impl.
         * 
         * This will cause client instantiated MetricIDs to 
         * throw an exception. (i.e the global MetricIDs)
         */
        constructorMID = new MetricID(CONSTRUCTOR_SIMPLE_TIMER_NAME);
        simpleTimerMIDs = MetricsUtil.createMetricIDs(SIMPLE_TIMER_NAMES);

        simpleTimerMIDsIncludingToString = new HashSet<>();
        simpleTimerMIDsIncludingToString.addAll(simpleTimerMIDs);
        simpleTimerMIDsIncludingToString.addAll(MetricsUtil.createMetricIDs(
            MetricsUtil.absoluteMetricNames(SimplyTimedClassBean.class, "simplyTimedClass", new String[] {"toString"})));
    }

    @Test
    @InSequence(1)
    public void simplyTimedMethodsNotCalledYet() {
        assertThat("SimpleTimers are not registered correctly", registry.getSimpleTimers().keySet(), is(equalTo(simpleTimerMIDsIncludingToString)));
        
        assertThat("Constructor timer count is incorrect", registry.getSimpleTimer(constructorMID).getCount(), is(equalTo(1L)));

        // Make sure that the method timers haven't been simplyTimed yet
        assertThat("Method simple timer counts are incorrect", registry.getSimpleTimers(METHOD_SIMPLE_TIMERS).values(),
                everyItem(Matchers.<SimpleTimer> hasProperty("count", equalTo(METHOD_COUNT.get()))));
    }

    @Test
    @InSequence(2)
    public void callSimplyTimedMethodsOnce() {
        assertThat("SimpleTimers are not registered correctly", registry.getSimpleTimers().keySet(), is(equalTo(simpleTimerMIDsIncludingToString)));
        
        assertThat("Constructor simple timer count is incorrect", registry.getSimpleTimer(constructorMID).getCount(), is(equalTo(1L)));

        // Call the simplyTimed methods and assert they've been simplyTimed
        bean.simplyTimedMethodOne();
        bean.simplyTimedMethodTwo();
        // Let's call the non-public methods as well
        bean.simplyTimedMethodProtected();
        bean.simplyTimedMethodPackagedPrivate();

        // Make sure that the method timers have been simplyTimed
        assertThat("Method simple timer counts are incorrect", registry.getSimpleTimers(METHOD_SIMPLE_TIMERS).values(),
                everyItem(Matchers.<SimpleTimer> hasProperty("count", equalTo(METHOD_COUNT.incrementAndGet()))));
    }
}