/*
 * 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.zookeeper.server.admin;

import java.util.LinkedHashMap;
import java.util.Map;

/**
 * A response from running a {@link Command}.
 */
public class CommandResponse {

    /**
     * The key in the map returned by {@link #toMap()} for the command name.
     */
    public static final String KEY_COMMAND = "command";
    /**
     * The key in the map returned by {@link #toMap()} for the error string.
     */
    public static final String KEY_ERROR = "error";

    private final String command;
    private final String error;
    private final Map<String, Object> data;

    /**
     * Creates a new response with no error string.
     *
     * @param command command name
     */
    public CommandResponse(String command) {
        this(command, null);
    }
    /**
     * Creates a new response.
     *
     * @param command command name
     * @param error error string (may be null)
     */
    public CommandResponse(String command, String error) {
        this.command = command;
        this.error = error;
        data = new LinkedHashMap<String, Object>();
    }

    /**
     * Gets the command name.
     *
     * @return command name
     */
    public String getCommand() {
        return command;
    }

    /**
     * Gets the error string (may be null).
     *
     * @return error string
     */
    public String getError() {
        return error;
    }

    /**
     * Adds a key/value pair to this response.
     *
     * @param key key
     * @param value value
     * @return prior value for key, or null if none
     */
    public Object put(String key, Object value) {
        return data.put(key, value);
    }

    /**
     * Adds all key/value pairs in the given map to this response.
     *
     * @param m map of key/value pairs
     */
    public void putAll(Map<? extends String,?> m) {
        data.putAll(m);
    }

    /**
     * Converts this response to a map. The returned map is mutable, and
     * changes to it do not reflect back into this response.
     *
     * @return map representation of response
     */
    public Map<String, Object> toMap() {
        Map<String, Object> m = new LinkedHashMap<String, Object>(data);
        m.put(KEY_COMMAND, command);
        m.put(KEY_ERROR, error);
        m.putAll(data);
        return m;
    }
}