using System;
using Goo;
using Sandbox;
using Sandbox.UI;
using static Sandbox.DemoTokens;

namespace Sandbox.RadialWheel;

// Center disc: idle = styled X dismiss button; hover = slot icon + title.
public static class Center
{
    public readonly record struct SlotContent( string Title, string IconSrc, bool IsSelected );

    const float XButtonSize        = 64f;
    const float XButtonBlur        = 6f;
    const float XButtonBgAlpha     = 0.85f;
    const float XButtonBorderAlpha = 0.08f;

    public static Container Build( SlotContent? hovered, float innerDiameterPx )
    {
        var iconColor  = (hovered is SlotContent s1 && s1.IsSelected) ? Hex( AccentYellow ) : Hex( FgPrimary );
        var titleColor = (hovered is SlotContent s2 && s2.IsSelected) ? AccentYellow : FgPrimary;

        var root = new Container
        {
            Key             = "center",
            Position        = PositionMode.Absolute,
            Top             = Length.Percent( 50 ),
            Left            = Length.Percent( 50 ),
            Width           = innerDiameterPx,
            Height          = innerDiameterPx,
            Transform       = Goo.PanelTransform.Translate( -innerDiameterPx * 0.5f, -innerDiameterPx * 0.5f ),
            FlexDirection   = FlexDirection.Column,
            JustifyContent  = Justify.Center,
            AlignItems      = Align.Center,
            PointerEvents   = PointerEvents.None,
        };

        if ( hovered is SlotContent slot )
        {
            root.Children.Add( new Goo.SvgPanel
            {
                Key    = "icon",
                Path   = slot.IconSrc,
                Color  = iconColor,
                Width  = 48f,
                Height = 48f,
            } );
            root.Children.Add( new Text( slot.Title )
            {
                Key       = "title",
                FontSize  = 18f,
                FontColor = titleColor,
            } );
        }
        else
        {
            var xButton = new Container
            {
                Key             = "x-button",
                Width           = XButtonSize,
                Height          = XButtonSize,
                BackgroundColor = Ink2.WithAlpha( XButtonBgAlpha ),
                BackdropFilterBlur = XButtonBlur,
                BorderColor     = FgPrimary.WithAlpha( XButtonBorderAlpha ),
                BorderWidth     = 1,
                BorderTopLeftRadius     = Length.Percent( 50 ),
                BorderTopRightRadius    = Length.Percent( 50 ),
                BorderBottomLeftRadius  = Length.Percent( 50 ),
                BorderBottomRightRadius = Length.Percent( 50 ),
                JustifyContent  = Justify.Center,
                AlignItems      = Align.Center,
                PointerEvents   = PointerEvents.None,
            };
            xButton.Children.Add( new Text( "×" )  // U+00D7 multiplication sign, heavier than lowercase x
            {
                Key       = "dismiss",
                FontSize  = 28f,
                FontColor = FgSecondary,
            } );
            root.Children.Add( xButton );
        }
        return root;
    }

    static string Hex( Color c )
    {
        int r = Math.Clamp( (int)( c.r * 255 ), 0, 255 );
        int g = Math.Clamp( (int)( c.g * 255 ), 0, 255 );
        int b = Math.Clamp( (int)( c.b * 255 ), 0, 255 );
        return $"#{r:X2}{g:X2}{b:X2}";
    }
}