using System.Diagnostics;
using InnovEnergy.Lib.Protocols.Modbus.Channels;
using InnovEnergy.Lib.Protocols.Modbus.Protocol.Frames.Accessors;
using InnovEnergy.Lib.Protocols.Modbus.Protocol.Frames.Commands;
using InnovEnergy.Lib.Protocols.Modbus.Protocol.Frames.Replies;
using InnovEnergy.Lib.Protocols.Modbus.Tcp;
using InnovEnergy.Lib.Utils;


namespace InnovEnergy.Lib.Protocols.Modbus.Clients;

using UInt16s = IReadOnlyCollection<UInt16>;
using Booleans = IReadOnlyCollection<Boolean>;

public class ModbusTcpClient : ModbusClient
{
    public const UInt16 DefaultPort = 502;
    private UInt16 _Id;
    
    [DebuggerStepThrough]
    private UInt16 NextId() => unchecked(++_Id);


    public ModbusTcpClient(Channel channel, Byte slaveId) : base(channel, slaveId)
    {
    }

    public override MbData ReadCoils(UInt16 readAddress, UInt16 nValues)
    {
        var id  = NextId(); // TODO: check response id
        
        var cmd = new ReadCoilsCommandFrame(SlaveId, readAddress, nValues);
        var hdr = new MbapHeader(id, cmd.Data.Count);  
        var frm = new ModbusTcpFrame(hdr, cmd);         

        Channel.Write(frm.Data);

        var hData = Channel.Read(MbapHeader.Size).ToArray();  
        var rxHdr = new MbapHeader(hData);

        var rxFrm = Channel
                   .Read(rxHdr.FrameLength)
                   .ToArray() // TODO: optimize .ToArray() ?
                   .Apply(ReadCoilsResponseFrame.Parse) 
                   .Apply(cmd.VerifyResponse);
        
        return new MbData(rxFrm.Coils.RawData, readAddress, Endian);
    }


    public override MbData ReadDiscreteInputs(UInt16 readAddress, UInt16 nValues)
    {
        var id  = NextId(); // TODO: check response id
        
        var cmd = new ReadDiscreteInputsCommandFrame(SlaveId, readAddress, nValues);
        var hdr = new MbapHeader(id, cmd.Data.Count);  
        var frm = new ModbusTcpFrame(hdr, cmd);         

        Channel.Write(frm.Data);

        var hData = Channel.Read(MbapHeader.Size).ToArray();  // TODO: optimize .ToArray() ?
        var rxHdr = new MbapHeader(hData);

        var rxFrm = Channel
                   .Read(rxHdr.FrameLength)
                   .ToArray()                          // TODO: optimize .ToArray() ?
                   .Apply(ReadDiscreteInputsResponseFrame.Parse)
                   .Apply(cmd.VerifyResponse);
        
        return new MbData(rxFrm.Inputs.RawData, readAddress, Endian);
    }

    public override MbData ReadInputRegisters(UInt16 readAddress, UInt16 nValues)
    {
        var id  = NextId(); // TODO: check response id

        var cmd = new ReadInputRegistersCommandFrame(SlaveId, readAddress, nValues);
        var hdr = new MbapHeader(id, cmd.Data.Count);
        var frm = new ModbusTcpFrame(hdr, cmd);

        Channel.Write(frm.Data);

        var hData = Channel.Read(MbapHeader.Size).ToArray();
        var rxHdr = new MbapHeader(hData);

        var rxFrm = Channel
                   .Read(rxHdr.FrameLength)
                   .ToArray()
                   .Apply(ReadInputRegistersResponseFrame.Parse)
                   .Apply(cmd.VerifyResponse);

        return new MbData(rxFrm.RegistersRead.RawData, readAddress, Endian);
    }


    public override MbData ReadHoldingRegisters(UInt16 readAddress, UInt16 nValues)
    {
        var id  = NextId(); // TODO: check response id
        
        var cmd = new ReadHoldingRegistersCommandFrame(SlaveId, readAddress, nValues);
        var hdr = new MbapHeader(id, cmd.Data.Count);
        var frm = new ModbusTcpFrame(hdr, cmd);

        Channel.Write(frm.Data);

        var hData = Channel.Read(MbapHeader.Size).ToArray();
        var rxHdr = new MbapHeader(hData);

        var rxFrm = Channel
                   .Read(rxHdr.FrameLength)
                   .ToArray()
                   .Apply(ReadHoldingRegistersResponseFrame.Parse)
                   .Apply(cmd.VerifyResponse);

        return new MbData(rxFrm.RegistersRead.RawData, readAddress, Endian);
    }

    public override UInt16 WriteCoils(UInt16 writeAddress, Booleans coils)
    {
        var id  = NextId(); // TODO: check response id
        var cmd = new WriteCoilsCommandFrame(SlaveId, writeAddress, coils);
        var hdr = new MbapHeader(id, cmd.Data.Count);
        var frm = new ModbusTcpFrame(hdr, cmd);

        Channel.Write(frm.Data);

        var hData = Channel.Read(MbapHeader.Size).ToArray();
        var rxHdr = new MbapHeader(hData);

        var rxFrm = Channel
                   .Read(rxHdr.FrameLength)
                   .ToArray()
                   .Apply(WriteCoilsResponseFrame.Parse)
                   .Apply(cmd.VerifyResponse);

        return rxFrm.NbWritten;
    }


    public override UInt16 WriteRegisters(UInt16 writeAddress, UInt16s values)
    {
        var id  = NextId(); // TODO: check response id
        var cmd = new WriteRegistersCommandFrame(SlaveId, writeAddress, values);
        var hdr = new MbapHeader(id, cmd.Data.Count);
        var frm = new ModbusTcpFrame(hdr, cmd);

        Channel.Write(frm.Data);

        var hData = Channel.Read(MbapHeader.Size).ToArray();
        var rxHdr = new MbapHeader(hData);

        var rxFrm = Channel
                   .Read(rxHdr.FrameLength)
                   .ToArray()
                   .Apply(WriteRegistersResponseFrame.Parse)
                   .Apply(cmd.VerifyResponse);

        return rxFrm.NbWritten;
    }

    public override MbData ReadWriteRegisters(UInt16 readAddress, UInt16 nbToRead, UInt16 writeAddress, UInt16s registersToWrite)
    {
        var id  = NextId(); // TODO: check response id
        
        var cmd = new ReadWriteRegistersCommandFrame(SlaveId, 
                                                     readAddress, 
                                                     nbToRead, 
                                                     writeAddress, 
                                                     registersToWrite);
        
        var hdr = new MbapHeader(id, cmd.Data.Count);
        var frm = new ModbusTcpFrame(hdr, cmd);

        Channel.Write(frm.Data);

        var hData = Enumerable.ToArray(Channel.Read(MbapHeader.Size));
        var rxHdr = new MbapHeader(hData);

        var fData = Enumerable.ToArray(Channel.Read(rxHdr.FrameLength));
        var rxFrm = fData
                   .Apply(ReadWriteRegistersResponseFrame.Parse)
                   .Apply(cmd.VerifyResponse);

        return new MbData(rxFrm.RegistersRead.RawData, readAddress, Endian);
    }

}