/*
 * Copyright 2020 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 org.traccar.BaseProtocolEncoder;
import org.traccar.Protocol;
import org.traccar.helper.Checksum;
import org.traccar.model.Command;

public class PstProtocolEncoder extends BaseProtocolEncoder {

    public PstProtocolEncoder(Protocol protocol) {
        super(protocol);
    }

    private ByteBuf encodeContent(long deviceId, int type, int data1, int data2) {

        ByteBuf buf = Unpooled.buffer();

        buf.writeInt((int) Long.parseLong(getUniqueId(deviceId)));
        buf.writeByte(0x06); // version

        buf.writeInt(1); // index
        buf.writeByte(PstProtocolDecoder.MSG_COMMAND);
        buf.writeShort(type);
        buf.writeShort(data1);
        buf.writeShort(data2);

        buf.writeShort(Checksum.crc16(Checksum.CRC16_XMODEM, buf.nioBuffer()));

        return buf;
    }

    @Override
    protected Object encodeCommand(Command command) {

        switch (command.getType()) {
            case Command.TYPE_ENGINE_STOP:
                return encodeContent(command.getDeviceId(), 0x0002, 0xffff, 0xffff);
            case Command.TYPE_ENGINE_RESUME:
                return encodeContent(command.getDeviceId(), 0x0001, 0xffff, 0xffff);
            default:
                return null;
        }
    }

}