/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF 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.
 */
package org.apache.tinkerpop.gremlin.server;

import org.apache.tinkerpop.gremlin.server.channel.UnifiedChannelizer;
import org.apache.tinkerpop.gremlin.server.channel.UnifiedChannelizerIntegrateTest;
import org.apache.tinkerpop.gremlin.server.op.OpLoader;
import org.apache.tinkerpop.gremlin.server.util.ServerGremlinExecutor;
import org.apache.tinkerpop.gremlin.tinkergraph.structure.TinkerGraph;
import org.junit.After;
import org.junit.Before;
import org.junit.Rule;
import org.junit.rules.TestName;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.File;
import java.io.InputStream;
import java.util.concurrent.CompletableFuture;

import static org.hamcrest.CoreMatchers.is;
import static org.junit.Assume.assumeThat;

/**
 * Starts and stops an instance for each executed test.
 *
 * @author Stephen Mallette (http://stephen.genoprime.com)
 */
public abstract class AbstractGremlinServerIntegrationTest {
    
    public static final String KEY_PASS = "changeit";
    public static final String JKS_SERVER_KEY = "src/test/resources/server-key.jks";
    public static final String JKS_SERVER_TRUST = "src/test/resources/server-trust.jks";
    public static final String JKS_CLIENT_KEY = "src/test/resources/client-key.jks";
    public static final String JKS_CLIENT_TRUST = "src/test/resources/client-trust.jks";
    public static final String P12_SERVER_KEY = "src/test/resources/server-key.p12";
    public static final String P12_SERVER_TRUST = "src/test/resources/server-trust.p12";
    public static final String P12_CLIENT_KEY = "src/test/resources/client-key.p12";
    public static final String P12_CLIENT_TRUST = "src/test/resources/client-trust.p12";
    public static final String KEYSTORE_TYPE_JKS = "jks";
    public static final String KEYSTORE_TYPE_PKCS12 = "pkcs12";
    public static final String TRUSTSTORE_TYPE_JKS = "jks";
    public static final String TRUSTSTORE_TYPE_PKCS12 = "pkcs12";

    protected GremlinServer server;
    private Settings overriddenSettings;
    private final static String epollOption = "gremlin.server.epoll";
    private static final boolean GREMLIN_SERVER_EPOLL = "true".equalsIgnoreCase(System.getProperty(epollOption));
    private static final Logger logger = LoggerFactory.getLogger(AbstractGremlinServerIntegrationTest.class);

    @Rule
    public TestName name = new TestName();

    public Settings overrideSettings(final Settings settings) {
        return settings;
    }

    /**
     * This method may be called after {@link #startServer()} to (re-)set the evaluation timeout in
     * the running server.
     * @param timeoutInMillis new evaluation timeout
     */
    protected void overrideEvaluationTimeout(final long timeoutInMillis) {
        // Note: overriding settings in a running server is not guaranteed to work for all settings.
        // It works for the evaluation timeout, though, because GremlinExecutor is re-created for each evaluation.
        overriddenSettings.evaluationTimeout = timeoutInMillis;
    }

    public InputStream getSettingsInputStream() {
        return AbstractGremlinServerIntegrationTest.class.getResourceAsStream("gremlin-server-integration.yaml");
    }

    @Before
    public void setUp() throws Exception {
        logger.info("Starting: " + name.getMethodName());

        startServer();
    }

    public void setUp(final Settings settings) throws Exception {
        logger.info("Starting: " + name.getMethodName());

        startServer(settings);
    }

    public void startServer(final Settings settings) throws Exception {
        if (null == settings) {
            startServer();
        } else {
            final Settings oSettings = overrideSettings(settings);

            if (shouldTestUnified()) {
                oSettings.channelizer = UnifiedChannelizer.class.getName();
            }

            ServerTestHelper.rewritePathsInGremlinServerSettings(oSettings);
            if (GREMLIN_SERVER_EPOLL) {
                oSettings.useEpollEventLoop = true;
            }
            this.server = new GremlinServer(oSettings);
            server.start().join();
        }
    }

    public void startServer() throws Exception {
        startServerAsync().join();
    }

    public CompletableFuture<ServerGremlinExecutor> startServerAsync() throws Exception {
        final InputStream stream = getSettingsInputStream();
        final Settings settings = Settings.read(stream);
        overriddenSettings = overrideSettings(settings);
        ServerTestHelper.rewritePathsInGremlinServerSettings(overriddenSettings);
        if (GREMLIN_SERVER_EPOLL) {
            overriddenSettings.useEpollEventLoop = true;
        }

        if (shouldTestUnified()) {
            overriddenSettings.channelizer = UnifiedChannelizer.class.getName();
        }

        this.server = new GremlinServer(overriddenSettings);

        return server.start();
    }

    @After
    public void tearDown() throws Exception {
        stopServer();
        logger.info("Ending: " + name.getMethodName());
    }

    public void stopServer() throws Exception {
        // calling close() on TinkerGraph does not free resources quickly enough. adding a clear() call let's gc
        // cleanup earlier
        server.getServerGremlinExecutor().getGraphManager().getAsBindings().values().stream()
                .filter(g -> g instanceof TinkerGraph).forEach(g -> ((TinkerGraph) g).clear());

        if (server != null) {
            server.stop().join();
        }

        // reset the OpLoader processors so that they can get reconfigured on startup - Settings may have changed
        // between tests
        OpLoader.reset();
    }

    protected boolean isUsingUnifiedChannelizer() {
        return server.getServerGremlinExecutor().
                getSettings().channelizer.equals(UnifiedChannelizer.class.getName());
    }

    public static boolean deleteDirectory(final File directory) {
        if (directory.exists()) {
            final File[] files = directory.listFiles();
            if (null != files) {
                for (int i = 0; i < files.length; i++) {
                    if (files[i].isDirectory()) {
                        deleteDirectory(files[i]);
                    } else {
                        files[i].delete();
                    }
                }
            }
        }

        return (directory.delete());
    }

    protected static void tryIncludeNeo4jGraph(final Settings settings) {
        if (isNeo4jPresent()) {
            deleteDirectory(new File("/tmp/neo4j"));
            settings.graphs.put("graph", "conf/neo4j-empty.properties");
        }
    }

    protected static boolean isNeo4jPresent() {
        try {
            Class.forName("org.neo4j.tinkerpop.api.impl.Neo4jGraphAPIImpl");
            return true;
        } catch (Throwable ex) {
            return false;
        }
    }

    protected static void assumeNeo4jIsPresent() {
        boolean neo4jIncludedForTesting = isNeo4jPresent();
        assumeThat("Neo4j implementation was not included for testing - run with -DincludeNeo4j", neo4jIncludedForTesting, is(true));
    }

    private boolean shouldTestUnified() {
        // ignore all tests in the UnifiedChannelizerIntegrateTest package as they are already rigged to test
        // over the various channelizer implementations
        return Boolean.parseBoolean(System.getProperty("testUnified", "false")) &&
                !this.getClass().getPackage().equals(UnifiedChannelizerIntegrateTest.class.getPackage());
    }
}
