package yaokong;

import java.nio.ByteBuffer;
import java.nio.ByteOrder;

import publicway.Gpstoxuzuobiao;

public class Control02 {
    
    /**
     * 构建基准站坐标指令（指令类型0x02）的HEX格式字符串
     * 
     * @param baseStationCoords 基准站坐标字符串，格式："纬度值,纬度方向,经度值,经度方向"
     *                          例如："3949.90238860,N,11616.75692000,E"
     * @return 基准站坐标指令的HEX格式字符串
     */
    public static String buildBaseStationCommandHex(String baseStationCoords) {
        // 解析坐标字符串
        String[] parts = baseStationCoords.split(",");
        if (parts.length != 4) {
            throw new IllegalArgumentException("基准站坐标格式错误，应为：纬度,纬度方向,经度,经度方向");
        }
        
        double latitude = parseDMToDecimal(parts[0].trim(), parts[1].trim());
        double longitude = parseDMToDecimal(parts[2].trim(), parts[3].trim());
        char latDirection = parts[1].trim().charAt(0);
        char lonDirection = parts[3].trim().charAt(0);
        
        byte[] commandBytes = buildBaseStationCommandBytes(latitude, longitude, latDirection, lonDirection);
        return bytesToHex(commandBytes);
    }
    
    /**
     * 构建基准站坐标指令的字节数组
     */
    public static byte[] buildBaseStationCommandBytes(double latitude, double longitude, 
                                                      char latDirection, char lonDirection) {
        // 验证参数
        if (latitude < -90.0 || latitude > 90.0) {
            throw new IllegalArgumentException("纬度值必须在-90.0到90.0之间");
        }
        if (longitude < -180.0 || longitude > 180.0) {
            throw new IllegalArgumentException("经度值必须在-180.0到180.0之间");
        }
        if (!(latDirection == 'N' || latDirection == 'S')) {
            throw new IllegalArgumentException("纬度方向必须是'N'或'S'");
        }
        if (!(lonDirection == 'E' || lonDirection == 'W')) {
            throw new IllegalArgumentException("经度方向必须是'E'或'W'");
        }
        
        int dataLength = 32; // 固定长度32字节
        
        ByteBuffer buffer = ByteBuffer.allocate(2 + 1 + 2 + 2 + dataLength + 2 + 1);
        buffer.order(ByteOrder.LITTLE_ENDIAN);
        
        // 帧头
        buffer.put(BluetoothProtocol.FRAME_HEADER);
        
        // 指令类型
        buffer.put((byte) 0x02);
        
        // 数据长度
        buffer.putShort((short) dataLength);
        
        // 序列号
        buffer.putShort((short) BluetoothProtocol.getNextSequence());
        
        // 纬度值 (double, 8字节)
        buffer.putDouble(latitude);
        
        // 经度值 (double, 8字节)
        buffer.putDouble(longitude);
        
        // 纬度方向 (char, 1字节)
        buffer.put((byte) latDirection);
        
        // 经度方向 (char, 1字节)
        buffer.put((byte) lonDirection);
        
        // 保留字段 (14字节，全部填0)
        for (int i = 0; i < 14; i++) {
            buffer.put((byte) 0x00);
        }
        
        // 计算CRC16
        byte[] dataForCRC = new byte[1 + 2 + 2 + dataLength];
        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((byte) 0x0D);
        
        return buffer.array();
    }
    
    /**
     * 将度分格式转换为十进制格式
     * 例如：3949.90238860 -> 39.83170647666667
     */
    private static double parseDMToDecimal(String dmm, String direction) {
        return Gpstoxuzuobiao.parseDMToDecimal(dmm, direction);
    }
    
    private static String bytesToHex(byte[] bytes) {
        StringBuilder hexString = new StringBuilder();
        for (int i = 0; i < bytes.length; i++) {
            String hex = Integer.toHexString(bytes[i] & 0xFF);
            if (hex.length() == 1) {
                hexString.append('0');
            }
            hexString.append(hex);
            if (i < bytes.length - 1) {
                hexString.append(' ');
            }
        }
        return hexString.toString().toUpperCase();
    }    
   
}