<?php

/**
 * Copyright 2016 LINE Corporation
 *
 * LINE Corporation 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:
 *
 *   https://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.
 */

namespace LINE\LINEBot\MessageBuilder;

use LINE\LINEBot\MessageBuilder;

class MultiMessageBuilder implements MessageBuilder
{
    /** @var MessageBuilder[] */
    private $messageBuilders = [];

    /**
     * Add a message builder.
     *
     * @param MessageBuilder $messageBuilder
     * @return MultiMessageBuilder $this
     */
    public function add(MessageBuilder $messageBuilder)
    {
        $this->messageBuilders[] = $messageBuilder;
        return $this;
    }

    /**
     * Builds message structure.
     *
     * @return array Built message structure.
     */
    public function buildMessage()
    {
        $messages = [];
        foreach ($this->messageBuilders as $messageBuilder) {
            foreach ($messageBuilder->buildMessage() as $message) {
                $messages[] = $message;
            }
        }

        return $messages;
    }
}