/*
 * 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.nifi.registry.flow;

import io.swagger.annotations.ApiModel;
import io.swagger.annotations.ApiModelProperty;
import org.apache.nifi.registry.bucket.Bucket;

import javax.validation.Valid;
import javax.validation.constraints.NotNull;
import javax.xml.bind.annotation.XmlRootElement;
import javax.xml.bind.annotation.XmlTransient;
import java.util.Objects;

/**
 * <p>
 * Represents a snapshot of a versioned flow. A versioned flow may change many times
 * over the course of its life. Each of these versions that is saved to the registry
 * is saved as a snapshot, representing information such as the name of the flow, the
 * version of the flow, the timestamp when it was saved, the contents of the flow, etc.
 * </p>
 */
@ApiModel
@XmlRootElement
public class VersionedFlowSnapshot {

    @Valid
    @NotNull
    private VersionedFlowSnapshotMetadata snapshotMetadata;

    @Valid
    @NotNull
    private VersionedProcessGroup flowContents;

    // read-only, only populated from retrieval of a snapshot
    private VersionedFlow flow;

    // read-only, only populated from retrieval of a snapshot
    private Bucket bucket;


    @ApiModelProperty(value = "The metadata for this snapshot", required = true)
    public VersionedFlowSnapshotMetadata getSnapshotMetadata() {
        return snapshotMetadata;
    }

    public void setSnapshotMetadata(VersionedFlowSnapshotMetadata snapshotMetadata) {
        this.snapshotMetadata = snapshotMetadata;
    }

    @ApiModelProperty(value = "The contents of the versioned flow", required = true)
    public VersionedProcessGroup getFlowContents() {
        return flowContents;
    }

    public void setFlowContents(VersionedProcessGroup flowContents) {
        this.flowContents = flowContents;
    }

    @ApiModelProperty(value = "The flow this snapshot is for", readOnly = true)
    public VersionedFlow getFlow() {
        return flow;
    }

    public void setFlow(VersionedFlow flow) {
        this.flow = flow;
    }

    @ApiModelProperty(value = "The bucket where the flow is located", readOnly = true)
    public Bucket getBucket() {
        return bucket;
    }

    public void setBucket(Bucket bucket) {
        this.bucket = bucket;
    }

    /**
     * This is a convenience method that will return true when flow is populated and when the flow's versionCount
     * is equal to the version of this snapshot.
     *
     * @return true if flow is populated and if this snapshot is the latest version for the flow at the time of retrieval
     */
    @XmlTransient
    public boolean isLatest() {
        return flow != null && snapshotMetadata != null && flow.getVersionCount() == getSnapshotMetadata().getVersion();
    }

    @Override
    public int hashCode() {
        return Objects.hash(this.snapshotMetadata);
    }

    @Override
    public boolean equals(final Object obj) {
        if (obj == null) {
            return false;
        }
        if (getClass() != obj.getClass()) {
            return false;
        }

        final VersionedFlowSnapshot other = (VersionedFlowSnapshot) obj;
        return Objects.equals(this.snapshotMetadata, other.snapshotMetadata);
    }

    @Override
    public String toString() {
        final String flowName = (flow == null ? "null" : flow.getName());
        return "VersionedFlowSnapshot[flowId=" + snapshotMetadata.getFlowIdentifier() + ", flowName=" + flowName
            + ", version=" + snapshotMetadata.getVersion() + ", comments=" + snapshotMetadata.getComments() + "]";
    }
}