/*
 * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
 * or more contributor license agreements. Licensed under the "Elastic License
 * 2.0", the "GNU Affero General Public License v3.0 only", and the "Server Side
 * Public License v 1"; you may not use this file except in compliance with, at
 * your election, the "Elastic License 2.0", the "GNU Affero General Public
 * License v3.0 only", or the "Server Side Public License, v 1".
 */

package org.elasticsearch.action.support.single.instance;

import org.elasticsearch.action.ActionRequestValidationException;
import org.elasticsearch.action.IndicesRequest;
import org.elasticsearch.action.LegacyActionRequest;
import org.elasticsearch.action.ValidateActions;
import org.elasticsearch.action.support.IndicesOptions;
import org.elasticsearch.common.io.stream.StreamInput;
import org.elasticsearch.common.io.stream.StreamOutput;
import org.elasticsearch.core.Nullable;
import org.elasticsearch.core.TimeValue;
import org.elasticsearch.index.shard.ShardId;

import java.io.IOException;

// TODO: This request and its associated transport action can be folded into UpdateRequest which is its only concrete production code
//       implementation
public abstract class InstanceShardOperationRequest<Request extends InstanceShardOperationRequest<Request>> extends LegacyActionRequest
    implements
        IndicesRequest {

    public static final TimeValue DEFAULT_TIMEOUT = TimeValue.timeValueMinutes(1);

    protected TimeValue timeout = DEFAULT_TIMEOUT;

    protected String index;
    // null means its not set, allows to explicitly direct a request to a specific shard
    protected ShardId shardId = null;

    private String concreteIndex;

    protected InstanceShardOperationRequest() {}

    protected InstanceShardOperationRequest(@Nullable ShardId shardId, StreamInput in) throws IOException {
        super(in);
        // Do a full read if no shard id is given (indicating that this instance isn't read as part of a BulkShardRequest or that `in` is of
        // an older version) and is in the format used by #writeTo.
        if (shardId == null) {
            index = in.readString();
            this.shardId = in.readOptionalWriteable(ShardId::new);
        } else {
            // We know a shard id so we read the format given by #writeThin
            this.shardId = shardId;
            if (in.readBoolean()) {
                index = in.readString();
            } else {
                index = shardId.getIndexName();
            }
        }
        timeout = in.readTimeValue();
        concreteIndex = in.readOptionalString();
    }

    public InstanceShardOperationRequest(String index) {
        this.index = index;
    }

    @Override
    public ActionRequestValidationException validate() {
        ActionRequestValidationException validationException = null;
        if (index == null) {
            validationException = ValidateActions.addValidationError("index is missing", validationException);
        }
        return validationException;
    }

    public String index() {
        return index;
    }

    @Override
    public String[] indices() {
        return new String[] { index };
    }

    @Override
    public IndicesOptions indicesOptions() {
        return IndicesOptions.strictSingleIndexNoExpandForbidClosed();
    }

    @SuppressWarnings("unchecked")
    public final Request index(String index) {
        this.index = index;
        return (Request) this;
    }

    public TimeValue timeout() {
        return timeout;
    }

    /**
     * A timeout to wait if the index operation can't be performed immediately. Defaults to {@code 1m}.
     */
    @SuppressWarnings("unchecked")
    public final Request timeout(TimeValue timeout) {
        this.timeout = timeout;
        return (Request) this;
    }

    public String concreteIndex() {
        return concreteIndex;
    }

    void concreteIndex(String concreteIndex) {
        this.concreteIndex = concreteIndex;
    }

    @Override
    public void writeTo(StreamOutput out) throws IOException {
        super.writeTo(out);
        out.writeString(index);
        out.writeOptionalWriteable(shardId);
        out.writeTimeValue(timeout);
        out.writeOptionalString(concreteIndex);
    }

    public void writeThin(StreamOutput out) throws IOException {
        super.writeTo(out);
        if (shardId != null && index.equals(shardId.getIndexName())) {
            out.writeBoolean(false);
        } else {
            out.writeBoolean(true);
            out.writeString(index);
        }
        out.writeTimeValue(timeout);
        out.writeOptionalString(concreteIndex);
    }
}