package yaokong;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;

public class ControlCommandSender extends WaitForAck {

    public ControlCommandSender(InputStream inputStream, OutputStream outputStream) {
        super(inputStream, outputStream);
    }

    // 下发设备控制动作与紧急等级指令
    public boolean sendControlCommand(byte action, byte emergencyLevel) throws IOException {
        ByteBuffer buffer = ByteBuffer.allocate(2 + 1 + 2 + 2 + 2 + 2 + 1);
        buffer.order(ByteOrder.LITTLE_ENDIAN);
        
        // 帧头
        buffer.put(BluetoothProtocol.FRAME_HEADER);
        // 指令类型
        buffer.put(BluetoothProtocol.CMD_CONTROL);
        // 数据长度
        buffer.putShort((short) 2);
        // 序列号
        buffer.putShort((short) BluetoothProtocol.getNextSequence());
        // 控制动作
        buffer.put(action);
        // 紧急等级
        buffer.put(emergencyLevel);
        
        // 计算CRC16
        byte[] dataForCRC = new byte[1 + 2 + 2 + 2];
        System.arraycopy(buffer.array(), 2, dataForCRC, 0, dataForCRC.length);
        int crc = CRC16.calculateCRC16(dataForCRC, 0, dataForCRC.length);
        buffer.putShort((short) crc);
        
        // 帧尾
        buffer.put(BluetoothProtocol.FRAME_FOOTER);
        
        outputStream.write(buffer.array());
        outputStream.flush();
        
        return waitForAck(BluetoothProtocol.CMD_CONTROL);
    }
}