/*
 * SPDX-License-Identifier: Apache-2.0
 *
 * The OpenSearch Contributors require contributions made to
 * this file be licensed under the Apache-2.0 license or a
 * compatible open source license.
 */

/*
 * Licensed to Elasticsearch under one or more contributor
 * license agreements. See the NOTICE file distributed with
 * this work for additional information regarding copyright
 * ownership. Elasticsearch 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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/*
 * Modifications Copyright OpenSearch Contributors. See
 * GitHub history for details.
 */

package org.opensearch.watcher;

import org.opensearch.common.settings.Settings;
import org.opensearch.test.OpenSearchTestCase;
import org.opensearch.threadpool.TestThreadPool;
import org.opensearch.threadpool.ThreadPool;

import static org.opensearch.common.unit.TimeValue.timeValueSeconds;
import static org.hamcrest.Matchers.equalTo;
import static org.hamcrest.Matchers.is;
import static org.hamcrest.Matchers.notNullValue;

public class ResourceWatcherServiceTests extends OpenSearchTestCase {
    public void testSettings() throws Exception {
        ThreadPool threadPool = new TestThreadPool("test");

        // checking the defaults
        Settings settings = Settings.builder().build();
        ResourceWatcherService service = new ResourceWatcherService(settings, threadPool);
        assertThat(service.highMonitor.interval, is(ResourceWatcherService.Frequency.HIGH.interval));
        assertThat(service.mediumMonitor.interval, is(ResourceWatcherService.Frequency.MEDIUM.interval));
        assertThat(service.lowMonitor.interval, is(ResourceWatcherService.Frequency.LOW.interval));

        // checking bwc
        settings = Settings.builder()
            .put("resource.reload.interval", "40s") // only applies to medium
            .build();
        service = new ResourceWatcherService(settings, threadPool);
        assertThat(service.highMonitor.interval.millis(), is(timeValueSeconds(5).millis()));
        assertThat(service.mediumMonitor.interval.millis(), is(timeValueSeconds(40).millis()));
        assertThat(service.lowMonitor.interval.millis(), is(timeValueSeconds(60).millis()));

        // checking custom
        settings = Settings.builder()
            .put("resource.reload.interval.high", "10s")
            .put("resource.reload.interval.medium", "20s")
            .put("resource.reload.interval.low", "30s")
            .build();
        service = new ResourceWatcherService(settings, threadPool);
        assertThat(service.highMonitor.interval.millis(), is(timeValueSeconds(10).millis()));
        assertThat(service.mediumMonitor.interval.millis(), is(timeValueSeconds(20).millis()));
        assertThat(service.lowMonitor.interval.millis(), is(timeValueSeconds(30).millis()));
        terminate(threadPool);
    }

    public void testHandle() throws Exception {
        ThreadPool threadPool = new TestThreadPool("test");
        Settings settings = Settings.builder().build();
        ResourceWatcherService service = new ResourceWatcherService(settings, threadPool);
        ResourceWatcher watcher = new ResourceWatcher() {
            @Override
            public void init() {}

            @Override
            public void checkAndNotify() {}
        };

        // checking default freq
        WatcherHandle handle = service.add(watcher);
        assertThat(handle, notNullValue());
        assertThat(handle.frequency(), equalTo(ResourceWatcherService.Frequency.MEDIUM));
        assertThat(service.lowMonitor.watchers.size(), is(0));
        assertThat(service.highMonitor.watchers.size(), is(0));
        assertThat(service.mediumMonitor.watchers.size(), is(1));
        handle.stop();
        assertThat(service.mediumMonitor.watchers.size(), is(0));
        handle.resume();
        assertThat(service.mediumMonitor.watchers.size(), is(1));
        handle.stop();

        // checking custom freq
        handle = service.add(watcher, ResourceWatcherService.Frequency.HIGH);
        assertThat(handle, notNullValue());
        assertThat(handle.frequency(), equalTo(ResourceWatcherService.Frequency.HIGH));
        assertThat(service.lowMonitor.watchers.size(), is(0));
        assertThat(service.mediumMonitor.watchers.size(), is(0));
        assertThat(service.highMonitor.watchers.size(), is(1));
        handle.stop();
        assertThat(service.highMonitor.watchers.size(), is(0));
        handle.resume();
        assertThat(service.highMonitor.watchers.size(), is(1));
        terminate(threadPool);
    }
}
