/*
 * 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.
 */

package org.elasticsearch.action.admin.cluster.snapshots.create;

import org.elasticsearch.ElasticsearchException;
import org.elasticsearch.action.ActionListener;
import org.elasticsearch.action.support.ActionFilters;
import org.elasticsearch.action.support.master.TransportMasterNodeOperationAction;
import org.elasticsearch.cluster.ClusterService;
import org.elasticsearch.cluster.ClusterState;
import org.elasticsearch.cluster.block.ClusterBlockException;
import org.elasticsearch.cluster.block.ClusterBlockLevel;
import org.elasticsearch.cluster.metadata.SnapshotId;
import org.elasticsearch.common.inject.Inject;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.snapshots.SnapshotInfo;
import org.elasticsearch.snapshots.SnapshotsService;
import org.elasticsearch.threadpool.ThreadPool;
import org.elasticsearch.transport.TransportService;

/**
 * Transport action for create snapshot operation
 */
public class TransportCreateSnapshotAction extends TransportMasterNodeOperationAction<CreateSnapshotRequest, CreateSnapshotResponse> {
    private final SnapshotsService snapshotsService;

    @Inject
    public TransportCreateSnapshotAction(Settings settings, TransportService transportService, ClusterService clusterService,
                                         ThreadPool threadPool, SnapshotsService snapshotsService, ActionFilters actionFilters) {
        super(settings, CreateSnapshotAction.NAME, transportService, clusterService, threadPool, actionFilters);
        this.snapshotsService = snapshotsService;
    }

    @Override
    protected String executor() {
        return ThreadPool.Names.SNAPSHOT;
    }

    @Override
    protected CreateSnapshotRequest newRequest() {
        return new CreateSnapshotRequest();
    }

    @Override
    protected CreateSnapshotResponse newResponse() {
        return new CreateSnapshotResponse();
    }

    @Override
    protected ClusterBlockException checkBlock(CreateSnapshotRequest request, ClusterState state) {
        // We are writing to the cluster metadata and reading from indices - so we need to check both blocks
        ClusterBlockException clusterBlockException = state.blocks().globalBlockedException(ClusterBlockLevel.METADATA_WRITE);
        if (clusterBlockException != null) {
            return clusterBlockException;
        }
        return state.blocks().indicesBlockedException(ClusterBlockLevel.READ, state.metaData().concreteIndices(request.indicesOptions(), request.indices()));
    }

    @Override
    protected void masterOperation(final CreateSnapshotRequest request, ClusterState state, final ActionListener<CreateSnapshotResponse> listener) throws ElasticsearchException {
        SnapshotsService.SnapshotRequest snapshotRequest =
                new SnapshotsService.SnapshotRequest("create_snapshot[" + request.snapshot() + "]", request.snapshot(), request.repository())
                        .indices(request.indices())
                        .indicesOptions(request.indicesOptions())
                        .partial(request.partial())
                        .settings(request.settings())
                        .includeGlobalState(request.includeGlobalState())
                        .masterNodeTimeout(request.masterNodeTimeout());
        snapshotsService.createSnapshot(snapshotRequest, new SnapshotsService.CreateSnapshotListener() {
            @Override
            public void onResponse() {
                if (request.waitForCompletion()) {
                    snapshotsService.addListener(new SnapshotsService.SnapshotCompletionListener() {
                        SnapshotId snapshotId = new SnapshotId(request.repository(), request.snapshot());

                        @Override
                        public void onSnapshotCompletion(SnapshotId snapshotId, SnapshotInfo snapshot) {
                            if (this.snapshotId.equals(snapshotId)) {
                                listener.onResponse(new CreateSnapshotResponse(snapshot));
                                snapshotsService.removeListener(this);
                            }
                        }

                        @Override
                        public void onSnapshotFailure(SnapshotId snapshotId, Throwable t) {
                            if (this.snapshotId.equals(snapshotId)) {
                                listener.onFailure(t);
                                snapshotsService.removeListener(this);
                            }
                        }
                    });
                } else {
                    listener.onResponse(new CreateSnapshotResponse());
                }
            }

            @Override
            public void onFailure(Throwable t) {
                listener.onFailure(t);
            }
        });
    }
}
