namespace FieldLogger.Resources.Styles;

public enum UlThemeMode
{
    Default,
    Sunlight,
}

/// <summary>Applies generated semantic colors. Call on the UI thread after app resources initialize.</summary>
public static class ThemeManager
{
    private static readonly string[] SemanticColors =
    [
        "Canvas", "Surface", "SurfaceRaised", "SurfaceStrong", "Text", "TextMuted",
        "Primary", "PrimaryPressed", "Accent", "Border", "Focus", "Map", "Success",
        "Warning", "Error", "Neutral", "Disabled", "OnStrong", "OnPrimary", "OnAccent",
    ];

    public static UlThemeMode Current { get; private set; } = UlThemeMode.Default;

    public static void Apply(UlThemeMode mode)
    {
        var resources = Application.Current?.Resources
            ?? throw new InvalidOperationException("Application resources are not initialized.");
        var prefix = mode == UlThemeMode.Sunlight ? "UlSunlightColor" : "UlDefaultColor";

        foreach (var name in SemanticColors)
        {
            if (!resources.TryGetValue($"{prefix}{name}", out var value) || value is not Color color)
            {
                throw new InvalidOperationException($"Generated theme token {prefix}{name} is missing.");
            }
            resources[$"UlColor{name}"] = color;
            resources[$"UlBrush{name}"] = new SolidColorBrush(color);
        }
        Current = mode;
    }
}