using System;
using RGB.NET.Core;

namespace RGB.NET.Devices.PicoPi;

/// <inheritdoc />
/// <summary>
/// Represents the update-queue performing updates for Pico-Pi HID-devices.
///  </summary>
public sealed class PicoPiHIDUpdateQueue : UpdateQueue
{
    #region Properties & Fields

    private readonly PicoPiSDK _sdk;
    private readonly int _channel;

    private readonly byte[] _dataBuffer;

    #endregion

    #region Constructors

    /// <summary>
    /// Initializes a new instance of the <see cref="PicoPiHIDUpdateQueue"/> class.
    /// </summary>
    /// <param name="updateTrigger">The update trigger used by this queue.</param>
    /// <param name="sdk">The sdk used to access the device.</param>
    /// <param name="channel">The channel to update.</param>
    /// <param name="ledCount">The maximum amount of leds to update.</param>
    public PicoPiHIDUpdateQueue(IDeviceUpdateTrigger updateTrigger, PicoPiSDK sdk, int channel, int ledCount)
        : base(updateTrigger)
    {
        this._sdk = sdk;
        this._channel = channel;

        _dataBuffer = new byte[ledCount * 3];
    }

    #endregion

    #region Methods

    /// <inheritdoc />
    protected override bool Update(ReadOnlySpan<(object key, Color color)> dataSet)
    {
        try
        {
            Span<byte> buffer = _dataBuffer;
            foreach ((object key, Color color) in dataSet)
            {
                int index = key as int? ?? -1;
                if (index < 0) continue;

                (byte _, byte r, byte g, byte b) = color.GetRGBBytes();
                int offset = index * 3;
                buffer[offset] = r;
                buffer[offset + 1] = g;
                buffer[offset + 2] = b;
            }

            _sdk.SendHidUpdate(buffer, _channel);

            return true;
        }
        catch (Exception ex)
        {
            PicoPiDeviceProvider.Instance.Throw(ex);
        }

        return false;
    }

    #endregion
}