/*
 * 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.flink.runtime.executiongraph;

import org.apache.flink.api.common.JobID;
import org.apache.flink.api.common.time.Time;
import org.apache.flink.configuration.Configuration;
import org.apache.flink.configuration.IllegalConfigurationException;
import org.apache.flink.configuration.JobManagerOptions;
import org.apache.flink.metrics.MetricGroup;
import org.apache.flink.runtime.JobException;
import org.apache.flink.runtime.blob.BlobWriter;
import org.apache.flink.runtime.checkpoint.CheckpointIDCounter;
import org.apache.flink.runtime.checkpoint.CheckpointStatsTracker;
import org.apache.flink.runtime.checkpoint.CheckpointsCleaner;
import org.apache.flink.runtime.checkpoint.CompletedCheckpointStore;
import org.apache.flink.runtime.checkpoint.MasterTriggerRestoreHook;
import org.apache.flink.runtime.checkpoint.hooks.MasterHooks;
import org.apache.flink.runtime.client.JobExecutionException;
import org.apache.flink.runtime.client.JobSubmissionException;
import org.apache.flink.runtime.deployment.TaskDeploymentDescriptorFactory;
import org.apache.flink.runtime.executiongraph.failover.flip1.partitionrelease.PartitionGroupReleaseStrategy;
import org.apache.flink.runtime.executiongraph.failover.flip1.partitionrelease.PartitionGroupReleaseStrategyFactoryLoader;
import org.apache.flink.runtime.executiongraph.metrics.DownTimeGauge;
import org.apache.flink.runtime.executiongraph.metrics.RestartTimeGauge;
import org.apache.flink.runtime.executiongraph.metrics.UpTimeGauge;
import org.apache.flink.runtime.io.network.partition.JobMasterPartitionTracker;
import org.apache.flink.runtime.jobgraph.JobGraph;
import org.apache.flink.runtime.jobgraph.JobVertex;
import org.apache.flink.runtime.jobgraph.jsonplan.JsonPlanGenerator;
import org.apache.flink.runtime.jobgraph.tasks.CheckpointCoordinatorConfiguration;
import org.apache.flink.runtime.jobgraph.tasks.JobCheckpointingSettings;
import org.apache.flink.runtime.scheduler.VertexParallelismStore;
import org.apache.flink.runtime.shuffle.ShuffleMaster;
import org.apache.flink.runtime.state.CheckpointStorage;
import org.apache.flink.runtime.state.CheckpointStorageLoader;
import org.apache.flink.runtime.state.StateBackend;
import org.apache.flink.runtime.state.StateBackendLoader;
import org.apache.flink.util.DynamicCodeLoadingException;
import org.apache.flink.util.SerializedValue;

import org.slf4j.Logger;

import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.concurrent.Executor;
import java.util.concurrent.ScheduledExecutorService;
import java.util.function.Supplier;

import static org.apache.flink.util.Preconditions.checkNotNull;

/**
 * Utility class to encapsulate the logic of building an {@link DefaultExecutionGraph} from a {@link
 * JobGraph}.
 */
public class DefaultExecutionGraphBuilder {

    public static DefaultExecutionGraph buildGraph(
            JobGraph jobGraph,
            Configuration jobManagerConfig,
            ScheduledExecutorService futureExecutor,
            Executor ioExecutor,
            ClassLoader classLoader,
            CompletedCheckpointStore completedCheckpointStore,
            CheckpointsCleaner checkpointsCleaner,
            CheckpointIDCounter checkpointIdCounter,
            Time rpcTimeout,
            MetricGroup metrics,
            BlobWriter blobWriter,
            Logger log,
            ShuffleMaster<?> shuffleMaster,
            JobMasterPartitionTracker partitionTracker,
            TaskDeploymentDescriptorFactory.PartitionLocationConstraint partitionLocationConstraint,
            ExecutionDeploymentListener executionDeploymentListener,
            ExecutionStateUpdateListener executionStateUpdateListener,
            long initializationTimestamp,
            VertexAttemptNumberStore vertexAttemptNumberStore,
            VertexParallelismStore vertexParallelismStore,
            Supplier<CheckpointStatsTracker> checkpointStatsTrackerFactory)
            throws JobExecutionException, JobException {

        checkNotNull(jobGraph, "job graph cannot be null");

        final String jobName = jobGraph.getName();
        final JobID jobId = jobGraph.getJobID();

        final JobInformation jobInformation =
                new JobInformation(
                        jobId,
                        jobName,
                        jobGraph.getSerializedExecutionConfig(),
                        jobGraph.getJobConfiguration(),
                        jobGraph.getUserJarBlobKeys(),
                        jobGraph.getClasspaths());

        final int maxPriorAttemptsHistoryLength =
                jobManagerConfig.getInteger(JobManagerOptions.MAX_ATTEMPTS_HISTORY_SIZE);

        final PartitionGroupReleaseStrategy.Factory partitionGroupReleaseStrategyFactory =
                PartitionGroupReleaseStrategyFactoryLoader.loadPartitionGroupReleaseStrategyFactory(
                        jobManagerConfig);

        // create a new execution graph, if none exists so far
        final DefaultExecutionGraph executionGraph;
        try {
            executionGraph =
                    new DefaultExecutionGraph(
                            jobInformation,
                            futureExecutor,
                            ioExecutor,
                            rpcTimeout,
                            maxPriorAttemptsHistoryLength,
                            classLoader,
                            blobWriter,
                            partitionGroupReleaseStrategyFactory,
                            shuffleMaster,
                            partitionTracker,
                            partitionLocationConstraint,
                            executionDeploymentListener,
                            executionStateUpdateListener,
                            initializationTimestamp,
                            vertexAttemptNumberStore,
                            vertexParallelismStore);
        } catch (IOException e) {
            throw new JobException("Could not create the ExecutionGraph.", e);
        }

        // set the basic properties

        try {
            executionGraph.setJsonPlan(JsonPlanGenerator.generatePlan(jobGraph));
        } catch (Throwable t) {
            log.warn("Cannot create JSON plan for job", t);
            // give the graph an empty plan
            executionGraph.setJsonPlan("{}");
        }

        // initialize the vertices that have a master initialization hook
        // file output formats create directories here, input formats create splits

        final long initMasterStart = System.nanoTime();
        log.info("Running initialization on master for job {} ({}).", jobName, jobId);

        for (JobVertex vertex : jobGraph.getVertices()) {
            String executableClass = vertex.getInvokableClassName();
            if (executableClass == null || executableClass.isEmpty()) {
                throw new JobSubmissionException(
                        jobId,
                        "The vertex "
                                + vertex.getID()
                                + " ("
                                + vertex.getName()
                                + ") has no invokable class.");
            }

            try {
                vertex.initializeOnMaster(classLoader);
            } catch (Throwable t) {
                throw new JobExecutionException(
                        jobId,
                        "Cannot initialize task '" + vertex.getName() + "': " + t.getMessage(),
                        t);
            }
        }

        log.info(
                "Successfully ran initialization on master in {} ms.",
                (System.nanoTime() - initMasterStart) / 1_000_000);

        // topologically sort the job vertices and attach the graph to the existing one
        List<JobVertex> sortedTopology = jobGraph.getVerticesSortedTopologicallyFromSources();
        if (log.isDebugEnabled()) {
            log.debug(
                    "Adding {} vertices from job graph {} ({}).",
                    sortedTopology.size(),
                    jobName,
                    jobId);
        }
        executionGraph.attachJobGraph(sortedTopology);

        if (log.isDebugEnabled()) {
            log.debug(
                    "Successfully created execution graph from job graph {} ({}).", jobName, jobId);
        }

        // configure the state checkpointing
        if (isCheckpointingEnabled(jobGraph)) {
            JobCheckpointingSettings snapshotSettings = jobGraph.getCheckpointingSettings();

            // load the state backend from the application settings
            final StateBackend applicationConfiguredBackend;
            final SerializedValue<StateBackend> serializedAppConfigured =
                    snapshotSettings.getDefaultStateBackend();

            if (serializedAppConfigured == null) {
                applicationConfiguredBackend = null;
            } else {
                try {
                    applicationConfiguredBackend =
                            serializedAppConfigured.deserializeValue(classLoader);
                } catch (IOException | ClassNotFoundException e) {
                    throw new JobExecutionException(
                            jobId, "Could not deserialize application-defined state backend.", e);
                }
            }

            final StateBackend rootBackend;
            try {
                rootBackend =
                        StateBackendLoader.fromApplicationOrConfigOrDefault(
                                applicationConfiguredBackend,
                                snapshotSettings.isChangelogStateBackendEnabled(),
                                jobManagerConfig,
                                classLoader,
                                log);
            } catch (IllegalConfigurationException | IOException | DynamicCodeLoadingException e) {
                throw new JobExecutionException(
                        jobId, "Could not instantiate configured state backend", e);
            }

            // load the checkpoint storage from the application settings
            final CheckpointStorage applicationConfiguredStorage;
            final SerializedValue<CheckpointStorage> serializedAppConfiguredStorage =
                    snapshotSettings.getDefaultCheckpointStorage();

            if (serializedAppConfiguredStorage == null) {
                applicationConfiguredStorage = null;
            } else {
                try {
                    applicationConfiguredStorage =
                            serializedAppConfiguredStorage.deserializeValue(classLoader);
                } catch (IOException | ClassNotFoundException e) {
                    throw new JobExecutionException(
                            jobId,
                            "Could not deserialize application-defined checkpoint storage.",
                            e);
                }
            }

            final CheckpointStorage rootStorage;
            try {
                rootStorage =
                        CheckpointStorageLoader.load(
                                applicationConfiguredStorage,
                                null,
                                rootBackend,
                                jobManagerConfig,
                                classLoader,
                                log);
            } catch (IllegalConfigurationException | DynamicCodeLoadingException e) {
                throw new JobExecutionException(
                        jobId, "Could not instantiate configured checkpoint storage", e);
            }

            // instantiate the user-defined checkpoint hooks

            final SerializedValue<MasterTriggerRestoreHook.Factory[]> serializedHooks =
                    snapshotSettings.getMasterHooks();
            final List<MasterTriggerRestoreHook<?>> hooks;

            if (serializedHooks == null) {
                hooks = Collections.emptyList();
            } else {
                final MasterTriggerRestoreHook.Factory[] hookFactories;
                try {
                    hookFactories = serializedHooks.deserializeValue(classLoader);
                } catch (IOException | ClassNotFoundException e) {
                    throw new JobExecutionException(
                            jobId, "Could not instantiate user-defined checkpoint hooks", e);
                }

                final Thread thread = Thread.currentThread();
                final ClassLoader originalClassLoader = thread.getContextClassLoader();
                thread.setContextClassLoader(classLoader);

                try {
                    hooks = new ArrayList<>(hookFactories.length);
                    for (MasterTriggerRestoreHook.Factory factory : hookFactories) {
                        hooks.add(MasterHooks.wrapHook(factory.create(), classLoader));
                    }
                } finally {
                    thread.setContextClassLoader(originalClassLoader);
                }
            }

            final CheckpointCoordinatorConfiguration chkConfig =
                    snapshotSettings.getCheckpointCoordinatorConfiguration();

            executionGraph.enableCheckpointing(
                    chkConfig,
                    hooks,
                    checkpointIdCounter,
                    completedCheckpointStore,
                    rootBackend,
                    rootStorage,
                    checkpointStatsTrackerFactory.get(),
                    checkpointsCleaner);
        }

        // create all the metrics for the Execution Graph

        metrics.gauge(RestartTimeGauge.METRIC_NAME, new RestartTimeGauge(executionGraph));
        metrics.gauge(DownTimeGauge.METRIC_NAME, new DownTimeGauge(executionGraph));
        metrics.gauge(UpTimeGauge.METRIC_NAME, new UpTimeGauge(executionGraph));

        return executionGraph;
    }

    public static boolean isCheckpointingEnabled(JobGraph jobGraph) {
        return jobGraph.getCheckpointingSettings() != null;
    }

    // ------------------------------------------------------------------------

    /** This class is not supposed to be instantiated. */
    private DefaultExecutionGraphBuilder() {}
}
