using System.Windows.Media;

namespace ytLive.Services.Compositor;

/// <summary>The colours and typefaces the ON-STREAM graphics paint with.
///
/// <para>Why this exists rather than reading <c>Themes/Tokens.xaml</c>: the renderers run on the
/// frame-pump thread and must never touch application resources or a dispatcher. They need frozen
/// values they can read from any thread.</para>
///
/// <para>Two groups live here, deliberately separated:</para>
/// <list type="bullet">
/// <item><b>Brand tokens</b> — a mirror of DESIGN.md. <c>OutputPaletteTests</c> parses the design
/// document and fails if any of these drifts from the theme, so the duplication cannot rot.</item>
/// <item><b>Event accents</b> — the alert box's own six-event colour language (gold for Super
/// Chats, violet for members, …). These are content, not chrome: the design standard has no
/// purple and should not grow one, but they still belong in ONE place instead of 57 scattered
/// literals.</item>
/// </list></summary>
public static class OutputPalette
{
    // ─── Brand tokens (must equal Themes/Tokens.xaml; guarded) ────────────────
    public static readonly Color Live = Color.FromRgb(0xff, 0x54, 0x51);        // primary
    public static readonly Color LiveDark = Color.FromRgb(0xb9, 0x1a, 0x24);    // primary-container
    public static readonly Color Amber = Color.FromRgb(0xff, 0xb9, 0x5f);       // secondary
    public static readonly Color Attention = Color.FromRgb(0xff, 0x8c, 0x3a);
    public static readonly Color Positive = Color.FromRgb(0x22, 0xc5, 0x5e);
    public static readonly Color Error = Color.FromRgb(0xef, 0x44, 0x44);
    public static readonly Color ErrorSurface = Color.FromRgb(0x93, 0x00, 0x0a);
    public static readonly Color Tertiary = Color.FromRgb(0x38, 0xbd, 0xf8);
    public static readonly Color TextPrimary = Color.FromRgb(0xda, 0xe2, 0xfd);
    public static readonly Color TextMuted = Color.FromRgb(0x94, 0xa3, 0xb8);
    public static readonly Color Background = Color.FromRgb(0x0b, 0x13, 0x26);
    public static readonly Color Surface = Color.FromRgb(0x17, 0x1f, 0x33);
    public static readonly Color SurfaceHigh = Color.FromRgb(0x22, 0x2a, 0x3d);
    public static readonly Color Outline = Color.FromRgb(0x33, 0x41, 0x55);

    // ─── Alert event accents (content language, not chrome) ───────────────────
    public static readonly Color Gold = Color.FromRgb(0xff, 0xd1, 0x66);
    public static readonly Color GoldBright = Color.FromRgb(0xff, 0xdd, 0x66);
    public static readonly Color GoldPale = Color.FromRgb(0xff, 0xf3, 0xc4);
    public static readonly Color WarmCream = Color.FromRgb(0xff, 0xe8, 0xd0);
    public static readonly Color Pink = Color.FromRgb(0xff, 0xb3, 0xd9);
    public static readonly Color Lilac = Color.FromRgb(0xf5, 0xd0, 0xfe);
    public static readonly Color Crimson = Color.FromRgb(0xf4, 0x2f, 0x5f);
    public static readonly Color MintText = Color.FromRgb(0xdb, 0xff, 0xf0);
    public static readonly Color Violet = Color.FromRgb(0xa7, 0x8b, 0xfa);

    /// <summary>The branding flash's halo channels. Red is the standard live red — one red in the
    /// product, including the credit — and the blue is lifted for luminance against a video feed.</summary>
    public static readonly Color NeonRed = Live;
    public static readonly Color NeonBlue = Color.FromRgb(0x4d, 0x8b, 0xff);

    // ─── Typefaces ───────────────────────────────────────────────────────────
    /// <summary>Bundled families (OFL). Resolved from the pack folder so on-stream graphics wear
    /// the same faces as the UI; a failure falls back to the system face rather than throwing
    /// inside a render tick.</summary>
    private static readonly System.Lazy<FontFamily> SansFamily = new(() => Family("Inter"));
    private static readonly System.Lazy<FontFamily> MonoFamily = new(() => Family("JetBrains Mono"));

    public static FontFamily Sans => SansFamily.Value;
    public static FontFamily Mono => MonoFamily.Value;

    /// <summary>The pack scheme only exists once WPF has registered it, so a static initializer
    /// must not build a pack URI: it throws a TypeInitializationException in any host without an
    /// Application (exactly what the first version did in the test process). Fall back to the
    /// family name, which resolves from the bundled resource or the system face.</summary>
    private static FontFamily Family(string name)
    {
        try { return new FontFamily(new System.Uri("pack://application:,,,/"), "/Assets/Fonts/#" + name); }
        catch (System.Exception) { return new FontFamily(name); }
    }

    public static SolidColorBrush Brush(Color colour)
    {
        var brush = new SolidColorBrush(colour);
        brush.Freeze();
        return brush;
    }
}