namespace Htmx.ApiDemo.Templates.Components;

/// <summary>
/// shadcn-style Button component.
/// Variant: default | destructive | outline | secondary | ghost | link
/// Size:    default | sm | lg | icon
/// </summary>
public sealed class Button : ButtonBase
{
    private static readonly Dictionary<string, string> VariantClasses = new()
    {
        ["default"]     = "bg-primary text-primary-foreground hover:bg-primary/90",
        ["destructive"] = "bg-destructive text-destructive-foreground hover:bg-destructive/90",
        ["outline"]     = "border border-input bg-transparent hover:bg-accent hover:text-accent-foreground",
        ["secondary"]   = "bg-secondary text-secondary-foreground hover:bg-secondary/80",
        ["ghost"]       = "hover:bg-accent hover:text-accent-foreground",
        ["link"]        = "text-primary underline-offset-4 hover:underline",
    };

    private static readonly Dictionary<string, string> SizeClasses = new()
    {
        ["default"] = "h-10 px-4 py-2 text-sm",
        ["sm"]      = "h-9 rounded-md px-3 text-xs",
        ["lg"]      = "h-11 rounded-md px-8 text-base",
        ["icon"]    = "h-10 w-10",
    };

    private const string BaseClasses =
        "inline-flex items-center justify-center gap-2 whitespace-nowrap rounded-md font-medium " +
        "ring-offset-background transition-colors " +
        "focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-ring focus-visible:ring-offset-2 " +
        "disabled:pointer-events-none disabled:opacity-50";

    private readonly byte[] _labelData;
    private readonly byte[] _classesData;
    private readonly byte[] _typeData;
    private readonly byte[] _hxAttrsData;

    public Button(
        string label,
        string variant = "default",
        string size    = "default",
        string type    = "button",
        string hxAttrs = "")
    {
        _labelData   = label.ToUtf8Bytes();
        _typeData    = type.ToUtf8Bytes();
        _hxAttrsData = hxAttrs.ToUtf8Bytes();

        var v = VariantClasses.GetValueOrDefault(variant, VariantClasses["default"]);
        var s = SizeClasses.GetValueOrDefault(size, SizeClasses["default"]);
        _classesData = $"{BaseClasses} {s} {v}".ToUtf8Bytes();
    }

    protected override void RenderLabel(HtmxRenderContext ctx)   => ctx.Writer.WriteUtf8(_labelData);
    protected override void RenderClasses(HtmxRenderContext ctx) => ctx.Writer.WriteUtf8(_classesData);
    protected override void RenderType(HtmxRenderContext ctx)    => ctx.Writer.WriteUtf8(_typeData);
    protected override void RenderHxAttrs(HtmxRenderContext ctx) => ctx.Writer.WriteUtf8(_hxAttrsData);
}