using DeviceCommand.Base;

public class Others : ModbusTcp
{
    private readonly byte _slaveId;

    /// <summary>
    /// 通道1PV
    /// </summary>
    private const ushort CH1_PV = 100;

    /// <summary>
    /// 通道2PV
    /// </summary>
    private const ushort CH2_PV = 102;

    /// <summary>
    /// 通道3PV
    /// </summary>
    private const ushort CH3_PV = 104;

    /// <summary>
    /// 通道4PV
    /// </summary>
    private const ushort CH4_PV = 106;

    public Others(
        byte slaveId,
        string ip,
        int port = 508,
        int sendTimeoutMs = 3000,
        int receiveTimeoutMs = 3000)
        : base()
    {
        _slaveId = slaveId;
        ConfigureDevice(ip, port, sendTimeoutMs, receiveTimeoutMs);
    }

    /// <summary>
    /// 读取通道1PV
    /// </summary>
    public async Task<float> ReadCH1Async(CancellationToken ct = default)
    {
        return await ReadRealAsync(CH1_PV, ct);
    }

    /// <summary>
    /// 读取通道2PV
    /// </summary>
    public async Task<float> ReadCH2Async(CancellationToken ct = default)
    {
        return await ReadRealAsync(CH2_PV, ct);
    }

    /// <summary>
    /// 读取通道3PV
    /// </summary>
    public async Task<float> ReadCH3Async(CancellationToken ct = default)
    {
        return await ReadRealAsync(CH3_PV, ct);
    }

    /// <summary>
    /// 读取通道4PV
    /// </summary>
    public async Task<float> ReadCH4Async(CancellationToken ct = default)
    {
        return await ReadRealAsync(CH4_PV, ct);
    }

    /// <summary>
    /// 一次读取4个通道PV
    /// </summary>
    public async Task<(float ch1, float ch2, float ch3, float ch4)> ReadAllAsync(CancellationToken ct = default)
    {
        ushort[] raw = await ReadHoldingRegistersAsync(_slaveId, 100, 8, ct);

        return
        (
            ToFloat(raw[0], raw[1]),
            ToFloat(raw[2], raw[3]),
            ToFloat(raw[4], raw[5]),
            ToFloat(raw[6], raw[7])
        );
    }

    private async Task<float> ReadRealAsync(ushort address, CancellationToken ct)
    {
        ushort[] raw = await ReadHoldingRegistersAsync(_slaveId, address, 2, ct);
        return ToFloat(raw[0], raw[1]);
    }

    private static float ToFloat(ushort high, ushort low)
    {
        byte[] bytes =
        {
            (byte)(high >> 8),
            (byte)high,
            (byte)(low >> 8),
            (byte)low
        };

        if (BitConverter.IsLittleEndian)
            Array.Reverse(bytes);

        return BitConverter.ToSingle(bytes, 0);
    }
}