/*
 * Copyright (c) 2016 Couchbase, Inc.
 *
 * Licensed 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 com.couchbase.client.core.message.kv.subdoc.simple;

import com.couchbase.client.core.annotations.InterfaceAudience;
import com.couchbase.client.core.annotations.InterfaceStability;
import com.couchbase.client.core.endpoint.kv.KeyValueHandler;
import io.netty.buffer.ByteBuf;

/**
 * A request covering all sub-document array operations (see {@link ArrayOperation}).
 *
 * @author Simon Baslé
 * @since 1.2
 */
@InterfaceStability.Experimental
@InterfaceAudience.Public
public class SubArrayRequest extends AbstractSubdocMutationRequest {

    private final ArrayOperation arrayOp;

    /**
     * Creates a new {@link SubArrayRequest} of type <i>arrayOp</i>.
     *
     * @param key        the key of the document.
     * @param path       the subdocument path to consider inside the document.
     * @param arrayOp    the specific {@link ArrayOperation} to perform.
     * @param fragment   the fragment of valid JSON to mutate into at the site denoted by the path.
     * @param bucket     the bucket of the document.
     * @param expiration the TTL of the whole enclosing document.
     * @param cas        the cas value for the operation
     * @throws NullPointerException if the path is null (see {@link #EXCEPTION_NULL_PATH})
     * @throws IllegalArgumentException if the operation is {@link ArrayOperation#INSERT} and path is empty (see {@link #EXCEPTION_EMPTY_PATH})
     */
    public SubArrayRequest(String key, String path, ArrayOperation arrayOp, ByteBuf fragment, String bucket, int expiration, long cas) {
        super(key, path, fragment, bucket, expiration, cas);
        this.arrayOp = arrayOp;
        if (path.isEmpty() && arrayOp == ArrayOperation.INSERT) {
            cleanUpAndThrow(EXCEPTION_EMPTY_PATH);
        }
    }

    /**
     * Creates a new {@link SubArrayRequest} of type <i>arrayOp</i>.
     *
     * @param key        the key of the document.
     * @param path       the subdocument path to consider inside the document.
     * @param arrayOp    the specific {@link ArrayOperation} to perform.
     * @param fragment   the fragment of valid JSON to mutate into at the site denoted by the path.
     * @param bucket     the bucket of the document.
     * @throws NullPointerException if the path is null (see {@link #EXCEPTION_NULL_PATH})
     * @throws IllegalArgumentException if the operation is {@link ArrayOperation#INSERT} and path is empty (see {@link #EXCEPTION_EMPTY_PATH})
     */
    public SubArrayRequest(String key, String path, ArrayOperation arrayOp, ByteBuf fragment, String bucket) {
        this(key, path, arrayOp, fragment, bucket, 0, 0L);
    }

    @Override
    public byte opcode() {
        return arrayOp.opCode();
    }

    /**
     * @return the more specific {@link ArrayOperation} this request describes.
     */
    public ArrayOperation arrayOperation() {
        return arrayOp;
    }

    public enum ArrayOperation {
        /**
         * Prepend an existing array with a value.
         */
        PUSH_FIRST(KeyValueHandler.OP_SUB_ARRAY_PUSH_FIRST),
        /**
         * Append a value to an existing array.
         */
        PUSH_LAST(KeyValueHandler.OP_SUB_ARRAY_PUSH_LAST),
        /**
         * Insert a value at a specific index into an existing array, shifting values at and after the given index.
         */
        INSERT(KeyValueHandler.OP_SUB_ARRAY_INSERT),
        /**
         * Add a value in an existing array unless the value already is present in the array.
         *
         * Existence of the value is tested via String comparison, and the array can only be containing primitive values.
         */
        ADD_UNIQUE(KeyValueHandler.OP_SUB_ARRAY_ADD_UNIQUE);

        private byte opCode;

        ArrayOperation(byte opCode) {
            this.opCode = opCode;
        }

        public byte opCode() {
            return this.opCode;
        }
    }
}