Delta-v/Content.Client/NetworkConfigurator/NetworkConfiguratorLinkMenu.xaml.cs

using System.Linq;
using System.Numerics;
using Content.Client.UserInterface.Controls;
using Content.Shared.DeviceLinking;
using Content.Shared.DeviceNetwork;
using Robust.Client.AutoGenerated;
using Robust.Client.Graphics;
using Robust.Client.UserInterface;
using Robust.Client.UserInterface.Controls;
using Robust.Client.UserInterface.XAML;
using Robust.Shared.Prototypes;

namespace Content.Client.NetworkConfigurator;

[GenerateTypedNameReferences]
public sealed partial class NetworkConfiguratorLinkMenu : FancyWindow
{
    [Dependency] private readonly IPrototypeManager _prototypeManager = default!;

    private const string PanelBgColor = "#202023";

    private readonly LinksRender _links;

    private readonly List<SourcePortPrototype> _sources = new();

    private readonly List<SinkPortPrototype> _sinks = new();

    private (ButtonPosition position, string id, int index)? _selectedButton;

    private List<(string left, string right)>? _defaults;

    public event Action? OnClearLinks;
    public event Action<string, string>? OnToggleLink;
    public event Action<List<(string left, string right)>>? OnLinkDefaults;

    public NetworkConfiguratorLinkMenu()
    {
        RobustXamlLoader.Load(this);
        IoCManager.InjectDependencies(this);

        var footerStyleBox = new StyleBoxFlat()
        {
            BorderThickness = new Thickness(0, 2, 0, 0),
            BorderColor = Color.FromHex("#5A5A5A")
        };

        FooterPanel.PanelOverride = footerStyleBox;
        MainPanel.PanelOverride = new StyleBoxFlat(Color.FromHex(PanelBgColor));

        ButtonClear.AddStyleClass("ButtonColorRed");
        ButtonLinkDefault.Disabled = true;

        _links = new LinksRender(ButtonContainerLeft, ButtonContainerRight);
        _links.VerticalExpand = true;
        MiddleContainer.AddChild(_links);

        ButtonOk.OnPressed += _ => Close();
        ButtonLinkDefault.OnPressed += _ => LinkDefaults();
        ButtonClear.OnPressed += _ => OnClearLinks?.Invoke();
    }

    public void UpdateState(DeviceLinkUserInterfaceState linkState)
    {
        ButtonContainerLeft.RemoveAllChildren();
        ButtonContainerRight.RemoveAllChildren();

        _sources.Clear();
        _sources.AddRange(linkState.Sources.Select(s => _prototypeManager.Index(s)));
        _links.SourceButtons.Clear();
        var i = 0;
        foreach (var source in _sources)
        {
            var button = CreateButton(ButtonPosition.Left, source.Name, source.Description, source.ID, i);
            ButtonContainerLeft.AddChild(button);
            _links.SourceButtons.Add(source.ID, button);
            i++;
        }

        _sinks.Clear();
        _sinks.AddRange(linkState.Sinks.Select(s => _prototypeManager.Index(s)));
        _links.SinkButtons.Clear();
        i = 0;
        foreach (var sink in _sinks)
        {
            var button = CreateButton(ButtonPosition.Right, sink.Name, sink.Description, sink.ID, i);
            ButtonContainerRight.AddChild(button);
            _links.SinkButtons.Add(sink.ID, button);
            i++;
        }

        _links.Links.Clear();
        _links.Links.AddRange(linkState.Links);
        _defaults = linkState.Defaults;

        ButtonLinkDefault.Disabled = _defaults == default;
        FromAddressLabel.Text = linkState.SourceAddress;
        ToAddressLabel.Text = linkState.SinkAddress;
    }

    private void LinkDefaults()
    {
        if (_defaults == default)
            return;

        OnLinkDefaults?.Invoke(_defaults);
    }

    private Button CreateButton(ButtonPosition position, string name, string description, string id, int index)
    {
        var button = new Button();
        button.AddStyleClass("OpenBoth");
        button.Text = Loc.GetString(name);
        button.ToolTip = Loc.GetString(description);
        button.ToggleMode = true;
        button.OnPressed += args => OnButtonPressed(args, position, id, index);
        return button;
    }

    private void OnButtonPressed(BaseButton.ButtonEventArgs args, ButtonPosition position, string id, int index)
    {
        var key = (position, id, index);
        if (_selectedButton == key)
        {
            args.Button.Pressed = false;
            _selectedButton = null;
            return;
        }

        if (!_selectedButton.HasValue)
        {
            args.Button.Pressed = true;
            _selectedButton = key;
            return;
        }

        if (_selectedButton.Value.position == position)
        {
            args.Button.Pressed = false;
            return;
        }

        var left = _selectedButton.Value.position == ButtonPosition.Left ? _selectedButton.Value.id : id;
        var right = _selectedButton.Value.position == ButtonPosition.Left ? id : _selectedButton.Value.id;

        OnToggleLink?.Invoke(left, right);

        args.Button.Pressed = false;

        var container = _selectedButton.Value.position == ButtonPosition.Left ? ButtonContainerLeft : ButtonContainerRight;
        if (container.GetChild(_selectedButton.Value.index) is Button button)
            button.Pressed = false;

        _selectedButton = null;
    }

    private enum ButtonPosition
    {
        Left,
        Right
    }

    /// <summary>
    ///  Draws lines between linked ports using bezier curve calculated with polynomial coefficients
    ///  See: https://youtu.be/jvPPXbo87ds?t=351
    /// </summary>
    private sealed class LinksRender : Control
    {
        public readonly List<(ProtoId<SourcePortPrototype>, ProtoId<SinkPortPrototype>)> Links = new();
        public readonly Dictionary<string, Button> SourceButtons = new();
        public readonly Dictionary<string, Button> SinkButtons = new();
        private readonly BoxContainer _leftButtonContainer;
        private readonly BoxContainer _rightButtonContainer;

        public LinksRender(BoxContainer leftButtonContainer, BoxContainer rightButtonContainer)
        {
            _leftButtonContainer = leftButtonContainer;
            _rightButtonContainer = rightButtonContainer;
        }

        protected override void Draw(DrawingHandleScreen handle)
        {
            foreach (var (left, right) in Links)
            {
                if (!SourceButtons.TryGetValue(left, out var leftChild) || !SinkButtons.TryGetValue(right, out var rightChild))
                    continue;

                var leftOffset = _leftButtonContainer.PixelPosition.Y;
                var rightOffset = _rightButtonContainer.PixelPosition.Y;

                var y1 = leftChild.PixelPosition.Y + leftChild.PixelHeight / 2 + leftOffset;
                var y2 = rightChild.PixelPosition.Y + rightChild.PixelHeight / 2 + rightOffset;

                if (left == right)
                {
                    handle.DrawLine(new Vector2(0, y1), new Vector2(PixelWidth, y2), Color.Cyan);
                    continue;
                }

                var controls = new List<Vector2>
                {
                    new(0, y1),
                    new(30, y1),
                    new(PixelWidth - 30, y2),
                    new(PixelWidth, y2),
                };

                //Calculate coefficients
                var c0 = controls[0];
                var c1 = controls[0] * -3 + controls[1] * 3;
                var c2 = controls[0] * 3 + controls[1] * -6 + controls[2] * 3;
                var c3 = controls[0] * -1 + controls[1] * 3 + controls[2] * -3 + controls[3];

                var points = new List<Vector2>();

                //Calculate points using coefficients
                for (float t = 0; t <= 1; t += 0.0001f)
                {
                    var point = c0 + c1 * t + c2 * (t * t) + c3 * (t * t * t);
                    points.Add(point);
                }

                handle.DrawPrimitives(DrawPrimitiveTopology.LineStrip, points.ToArray(), Color.Cyan);
            }
        }
    }
}