namespace JiLinApp.Docking.Ptz;

/// <summary>
/// dot.NET Implementation of Pelco P Protocol
/// </summary>
public class PelcoP
{
    private const byte STX = 0xA0;
    private const byte ETX = 0xAF;

    #region Pan and Tilt Commands

    #region Data1

    private const byte FocusFar = 0x01;
    private const byte FocusNear = 0x02;
    private const byte IrisOpen = 0x04;
    private const byte IrisClose = 0x08;
    private const byte CameraOnOff = 0x10;
    private const byte AutoscanOn = 0x20;
    private const byte CameraOn = 0x40;

    #endregion Data1

    #region Data2

    private const byte PanRight = 0x02;
    private const byte PanLeft = 0x04;
    private const byte TiltUp = 0x08;
    private const byte TiltDown = 0x10;
    private const byte ZoomTele = 0x20;
    private const byte ZoomWide = 0x40;

    #endregion Data2

    #region Data3

    public static byte PanSpeedMin = 0x00;
    public static byte PanSpeedMax = 0x3F;

    #endregion Data3

    #region Data4

    public static byte TiltSpeedMin = 0x00;
    public static byte TiltSpeedMax = 0x3F;

    #endregion Data4

    #endregion Pan and Tilt Commands

    #region Enums

    public enum PatternAction
    {
        Start,
        Stop,
        Run
    }

    public enum Action
    {
        Start,
        Stop
    }

    public enum LensSpeed
    {
        Low = 0x00,
        Medium = 0x01,
        High = 0x02,
        Turbo = 0x03
    }

    public enum Pan
    {
        Left = PanLeft,
        Right = PanRight
    }

    public enum Tilt
    {
        Up = TiltUp,
        Down = TiltDown
    }

    public enum Iris
    {
        Open = IrisOpen,
        Close = IrisClose
    }

    public enum Zoom
    {
        Wide = ZoomWide,
        Tele = ZoomTele
    }

    public enum Switch
    {
        On,
        Off
    }

    public enum Focus
    {
        Near = FocusNear,
        Far = FocusFar
    }

    public enum PresetAction
    {
        Set = 0x03,
        Clear = 0x05,
        Goto = 0x07
    }

    #endregion Enums

    #region Extended Command Set

    public static byte[] Preset(uint deviceAddress, PresetAction action, byte presetId)
    {
        return Message.GetMessage(deviceAddress, 0x00, (byte)action, 0x00, presetId);
    }

    public static byte[] Flip(uint deviceAddress)
    {
        return Message.GetMessage(deviceAddress, 0x00, 0x07, 0x00, 0x21);
    }

    public static byte[] ZeroPanPosition(uint deviceAddress)
    {
        return Message.GetMessage(deviceAddress, 0x00, 0x07, 0x00, 0x22);
    }

    public static byte[] AutoScan(uint deviceAddress, Action action)
    {
        byte m_action;
        if (action == Action.Start)
            m_action = 0x09;
        else
            m_action = 0x0B;
        return Message.GetMessage(deviceAddress, 0x00, m_action, 0x00, 0x00);
    }

    public static byte[] RemoteReset(uint deviceAddress)
    {
        return Message.GetMessage(deviceAddress, 0x00, 0x0F, 0x00, 0x00);
    }

    public static byte[] Zone(uint deviceAddress, byte zone, Action action)
    {
        if (zone < 0x01 & zone > 0x08)
            throw new Exception("Zone value should be between 0x01 and 0x08 include");
        byte m_action;
        if (action == Action.Start)
            m_action = 0x11;
        else
            m_action = 0x13;

        return Message.GetMessage(deviceAddress, 0x00, m_action, 0x00, zone);
    }

    public static byte[] WriteToScreen(uint deviceAddress, string text)
    {
        if (text.Length > 40)
            text = text.Remove(40, text.Length - 40);
        System.Text.Encoding encoding = System.Text.Encoding.ASCII;
        byte[] m_bytes = new byte[encoding.GetByteCount(text) * 8];
        int i = 0;
        byte m_scrPosition;
        byte m_ASCIIchr;

        foreach (char ch in text)
        {
            m_scrPosition = Convert.ToByte(i / 8);
            m_ASCIIchr = Convert.ToByte(ch);
            Array.Copy(
                Message.GetMessage(deviceAddress, 0x00, 0x15, m_scrPosition, m_ASCIIchr),
                0,
                m_bytes,
                i,
                8
            );
            i += 8;
        }

        return m_bytes;
    }

    public static byte[] ClearScreen(uint deviceAddress)
    {
        return Message.GetMessage(deviceAddress, 0x00, 0x17, 0x00, 0x00);
    }

    public static byte[] AlarmAcknowledge(uint deviceAddress, uint alarmID)
    {
        if (alarmID < 1 & alarmID > 8)
            throw new Exception("Only 8 alarms allowed for Pelco P implementation");
        return Message.GetMessage(deviceAddress, 0x00, 0x19, 0x00, Convert.ToByte(alarmID));
    }

    public static byte[] ZoneScan(uint deviceAddress, Action action)
    {
        byte m_action;
        if (action == Action.Start)
            m_action = 0x1B;
        else
            m_action = 0x1D;
        return Message.GetMessage(deviceAddress, 0x00, m_action, 0x00, 0x00);
    }

    public static byte[] Pattern(uint deviceAddress, PatternAction action)
    {
        byte m_action = action switch
        {
            PatternAction.Start => 0x1F,
            PatternAction.Stop => 0x21,
            PatternAction.Run => 0x23,
            _ => 0x23,
        };
        return Message.GetMessage(deviceAddress, 0x00, m_action, 0x00, 0x00);
    }

    public static byte[] SetZoomLensSpeed(uint deviceAddress, LensSpeed speed)
    {
        return Message.GetMessage(deviceAddress, 0x00, 0x25, 0x00, (byte)speed);
    }

    public static byte[] SetFocusLensSpeed(uint deviceAddress, LensSpeed speed)
    {
        return Message.GetMessage(deviceAddress, 0x00, 0x27, 0x00, (byte)speed);
    }

    #endregion Extended Command Set

    #region Base Command Set

    public static byte[] CameraSwitch(uint deviceAddress, Switch action)
    {
        byte m_action = CameraOnOff;
        if (action == Switch.On)
            m_action += CameraOnOff; //Maybe wrong !!!
        return Message.GetMessage(deviceAddress, m_action, 0x00, 0x00, 0x00);
    }

    public static byte[] CameraIrisSwitch(uint deviceAddress, Iris action)
    {
        return Message.GetMessage(deviceAddress, (byte)action, 0x00, 0x00, 0x00);
    }

    public static byte[] CameraFocus(uint deviceAddress, Focus action)
    {
        return Message.GetMessage(deviceAddress, (byte)action, 0x00, 0x00, 0x00);
    }

    public static byte[] CameraZoom(uint deviceAddress, Zoom action)
    {
        return Message.GetMessage(deviceAddress, 0x00, (byte)action, 0x00, 0x00);
    }

    public static byte[] CameraTilt(uint deviceAddress, Tilt action, uint speed)
    {
        if (speed < TiltSpeedMin)
            speed = TiltSpeedMin;
        if (speed > TiltSpeedMax)
            speed = TiltSpeedMax;
        return Message.GetMessage(deviceAddress, 0x00, (byte)action, 0x00, (byte)speed);
    }

    public static byte[] CameraPan(uint deviceAddress, Pan action, uint speed)
    {
        if (speed < PanSpeedMin)
            speed = PanSpeedMin;
        if (speed > PanSpeedMax)
            speed = PanSpeedMax;
        return Message.GetMessage(deviceAddress, 0x00, (byte)action, (byte)speed, 0x00);
    }

    public static byte[] CameraPanTilt(
        uint deviceAddress,
        Pan panAction,
        uint panSpeed,
        Tilt tiltAction,
        uint tiltSpeed
    )
    {
        byte[] m_tiltMessage = CameraTilt(deviceAddress, tiltAction, tiltSpeed);
        byte[] m_panMessage = CameraPan(deviceAddress, panAction, panSpeed);
        byte[] m_bytes = Message.GetMessage(
            deviceAddress,
            0x00,
            (byte)(m_tiltMessage[3] + m_panMessage[3]),
            m_panMessage[4],
            m_tiltMessage[5]
        );
        return m_bytes;
    }

    public static byte[] CameraStop(uint deviceAddress)
    {
        return Message.GetMessage(deviceAddress, 0x00, 0x00, 0x00, 0x00);
    }

    #endregion Base Command Set

    public struct Message
    {
        public static byte Address;
        public static byte CheckSum;

        public static byte Data1,
            Data2,
            Data3,
            Data4;

        public static byte[] GetMessage(
            uint address,
            byte data1,
            byte data2,
            byte data3,
            byte data4
        )
        {
            if (address < 0 & address > 32)
                throw new Exception("Protocol Pelco P support 32 devices only");
            Address = byte.Parse((address - 1).ToString());
            Data1 = data1;
            Data2 = data2;
            Data3 = data3;
            Data4 = data4;
            CheckSum = (byte)(STX ^ Address ^ Data1 ^ Data2 ^ Data3 ^ Data4 ^ ETX);
            return new byte[] { STX, Address, Data1, Data2, Data3, Data4, ETX, CheckSum };
        }
    }
}