import * as React from "react";
import { Slot } from "@radix-ui/react-slot";
import { cva, type VariantProps } from "class-variance-authority";
import { Loader2 } from "lucide-react";
import { cn } from "@/lib/utils";

const buttonVariants = cva(
  "inline-flex items-center justify-center gap-2 whitespace-nowrap rounded-md text-sm font-medium transition-[background-color,border-color,color,box-shadow,transform] duration-150 select-none disabled:pointer-events-none disabled:opacity-50 active:translate-y-px [&_svg]:pointer-events-none [&_svg]:shrink-0 [&_svg:not([class*='size-'])]:size-4",
  {
    variants: {
      variant: {
        default: "bg-fg text-bg hover:bg-fg/90 shadow-xs",
        primary: "bg-accent text-accent-fg hover:brightness-110 shadow-xs",
        secondary: "bg-bg-muted text-fg hover:bg-border",
        outline: "border border-border bg-bg hover:bg-bg-subtle text-fg shadow-xs",
        ghost: "hover:bg-bg-muted text-fg-muted hover:text-fg",
        danger: "bg-danger text-white hover:brightness-110 shadow-xs",
        link: "text-accent underline-offset-4 hover:underline h-auto p-0",
      },
      size: {
        default: "h-9 px-3.5",
        sm: "h-8 px-3 text-[13px] rounded-md",
        xs: "h-7 px-2.5 text-xs rounded-sm",
        lg: "h-10 px-5 text-[15px] rounded-lg",
        icon: "size-9",
        "icon-sm": "size-8",
      },
    },
    defaultVariants: { variant: "default", size: "default" },
  },
);

export interface ButtonProps extends React.ButtonHTMLAttributes<HTMLButtonElement>, VariantProps<typeof buttonVariants> {
  asChild?: boolean;
  loading?: boolean;
}

export const Button = React.forwardRef<HTMLButtonElement, ButtonProps>(({ className, variant, size, asChild = false, loading, children, disabled, ...props }, ref) => {
  if (asChild) {
    // Slot requires exactly one child element; the loader is not rendered in asChild mode.
    return (
      <Slot className={cn(buttonVariants({ variant, size, className }))} ref={ref} {...props}>
        {children}
      </Slot>
    );
  }
  return (
    <button className={cn(buttonVariants({ variant, size, className }))} ref={ref} disabled={disabled || loading} {...props}>
      {loading ? <Loader2 className="animate-spin" aria-hidden /> : null}
      {children}
    </button>
  );
});
Button.displayName = "Button";

export { buttonVariants };