namespace SpeckStudio.Avalonia.Controls.Views;

public partial class ScottSignalPlotView : UserControl
{
    public ScottSignalPlotView()
    {
        InitializeComponent();
        plot.Plot.Add.Signal(ScottPlot.Generate.Sin());
        plot.Plot.Add.Signal(ScottPlot.Generate.Cos());
        plot.PointerPressed += Plot_PointerPressed;
        plot.PointerMoved += Plot_PointerMoved;
        plot.PointerReleased += Plot_PointerReleased;

        var verticalLine = plot.Plot.Add.VerticalLine(0.5, 3);
        verticalLine.IsDraggable = true;
        verticalLine.Text = "Marker1";
        
        var horizontalLine = plot.Plot.Add.HorizontalLine(0.5, 3);
        horizontalLine.IsDraggable = true;
        horizontalLine.Text = "Marker2";
        horizontalLine.LabelAlignment = Alignment.MiddleRight;
        
    }
    AxisLine? PlottableBeingDragged = null;
    private void Plot_PointerReleased(object sender, PointerReleasedEventArgs e)
    {
        PlottableBeingDragged = null;
        plot.UserInputProcessor.Enable(); // enable panning again
    }

    private void Plot_PointerMoved(object sender, PointerEventArgs e)
    {
        // this rectangle is the area around the mouse in coordinate units
        var position = e.GetCurrentPoint(this);
        CoordinateRect rect = plot.Plot.GetCoordinateRect((float)position.Position.X, (float)position.Position.Y, radius: 10);

        if (PlottableBeingDragged is null)
        {
            //set cursor based on what's beneath the plottable
            var lineUnderMouse = GetLineUnderMouse(e);
            if (lineUnderMouse is null) Cursor = new Cursor(StandardCursorType.Arrow);
            else if (lineUnderMouse.IsDraggable && lineUnderMouse is VerticalLine) Cursor = new Cursor(StandardCursorType.SizeWestEast);
            else if (lineUnderMouse.IsDraggable && lineUnderMouse is HorizontalLine) Cursor = new Cursor(StandardCursorType.SizeNorthSouth);
        }
        else
        {
            // update the position of the plottable being dragged
            if (PlottableBeingDragged is HorizontalLine hl)
            {
                hl.Y = rect.VerticalCenter;
                hl.Text = $"{hl.Y:0.00}";
            }
            else if (PlottableBeingDragged is VerticalLine vl)
            {
                vl.X = rect.HorizontalCenter;
                vl.Text = $"{vl.X:0.00}";
            }
            plot.Refresh();
        }
    }

    MouseDragPanEx dragPan = null;
    private void Plot_PointerPressed(object sender, PointerPressedEventArgs e)
    {
        PlottableBeingDragged = GetLineUnderMouse(e);
        if (PlottableBeingDragged != null)
        {
            plot.UserInputProcessor.Disable();
        }
    }
    
    private AxisLine? GetLineUnderMouse(PointerEventArgs e)
    {
        var position = e.GetCurrentPoint(this);
        CoordinateRect rect = plot.Plot.GetCoordinateRect((float)position.Position.X, (float)position.Position.Y, radius: 10);

        foreach (AxisLine axLine in plot.Plot.GetPlottables<AxisLine>())
        {
            if (axLine.IsUnderMouse(rect))
                return axLine;
        }

        return null;
    }
}