using InnovEnergy.Lib.Protocols.Modbus.Protocol.Frames.Accessors;
using InnovEnergy.Lib.Protocols.Modbus.Protocol.Frames.Replies;
using InnovEnergy.Lib.Utils;
using static InnovEnergy.Lib.Protocols.Modbus.Protocol.FunctionCode;
using static InnovEnergy.Lib.Protocols.Modbus.Protocol.Frames.Constants;


namespace InnovEnergy.Lib.Protocols.Modbus.Protocol.Frames.Commands;

using MbFc = MbByte<FunctionCode>;

internal class ReadDiscreteInputsCommandFrame : ModbusFrame
{
    private const Int32 Size = 6;

    private MbAddress ReadAddress      => Data.AddressAt(2);
    private MbWord    QuantityOfInputs => Data.WordAt(4);
    

    public ReadDiscreteInputsCommandFrame(Byte slave, UInt16 readAddress, UInt16 nBits) : base(Size)
    {
        if (nBits > MaxDiscreteInputs)
            throw new ArgumentOutOfRangeException($"Maximum number of registers ({MaxDiscreteInputs}) exceeeded!", nameof(nBits));

        SlaveAddress    .Set(slave);
        FunctionCode    .Set(ReadDiscreteInputs);
        ReadAddress     .Set(readAddress); 
        QuantityOfInputs.Set(nBits);
    }


    private ReadDiscreteInputsCommandFrame(ArraySegment<Byte> data) : base(data)
    {
        if (data.Count != Size)
            throw new ArgumentException($"Expecting an array of size {Size}", nameof(data));

        AssertFunctionCode(ReadDiscreteInputs);
    }

    public ReadDiscreteInputResponseFrame VerifyResponse(ReadDiscreteInputResponseFrame response)
    {
        if (response.SlaveAddress != SlaveAddress)
            throw new UnexpectedResponseFieldException(nameof(response.SlaveAddress), SlaveAddress.ToString(), response.SlaveAddress);

        if (response.Inputs.Count != Math.Ceiling(QuantityOfInputs / 8.0).ConvertTo<Int32>() * 8)
            throw new UnexpectedResponseFieldException(nameof(response.Inputs), QuantityOfInputs.ToString(), response.Inputs.Count);

        return response;
    }

    public static ReadDiscreteInputsCommandFrame Parse(ArraySegment<Byte> data)
    {
        return new ReadDiscreteInputsCommandFrame(data);
    }
}