/*
 * Copyright 2021 Anton Tananaev (anton@traccar.org)
 *
 * 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 org.traccar.protocol;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelHandler;
import io.netty.channel.ChannelHandlerContext;
import io.netty.handler.codec.MessageToMessageEncoder;
import org.traccar.Context;
import org.traccar.Protocol;
import org.traccar.config.Keys;

import java.util.List;

@ChannelHandler.Sharable
public class TaipPrefixEncoder extends MessageToMessageEncoder<ByteBuf> {

    private final Protocol protocol;

    public TaipPrefixEncoder(Protocol protocol) {
        this.protocol = protocol;
    }

    @Override
    protected void encode(ChannelHandlerContext ctx, ByteBuf msg, List<Object> out) throws Exception {
        if (Context.getConfig().getBoolean(Keys.PROTOCOL_PREFIX.withPrefix(protocol.getName()))) {
            out.add(Unpooled.wrappedBuffer(Unpooled.wrappedBuffer(new byte[] {0x20, 0x20, 0x06, 0x00}), msg.retain()));
        } else {
            out.add(msg.retain());
        }
    }

}