better-auth/demo/nextjs/components/ui/button.tsx

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

import { cn } from "@/lib/utils";

const buttonVariants = cva(
	"inline-flex items-center justify-center whitespace-nowrap rounded-md text-sm font-medium transition-colors focus-visible:outline-none focus-visible:ring-1 focus-visible:ring-ring disabled:pointer-events-none disabled:opacity-50",
	{
		variants: {
			variant: {
				default:
					"bg-primary text-primary-foreground shadow hover:bg-primary/90",
				destructive:
					"bg-destructive text-destructive-foreground shadow-sm hover:bg-destructive/90",
				outline:
					"border border-input bg-background shadow-sm hover:bg-accent hover:text-accent-foreground",
				secondary:
					"bg-secondary text-secondary-foreground shadow-sm hover:bg-secondary/80",
				ghost: "hover:bg-accent hover:text-accent-foreground",
				link: "text-primary underline-offset-4 hover:underline",
			},
			size: {
				default: "h-9 px-4 py-2",
				sm: "h-8 rounded-md px-3 text-xs",
				lg: "h-10 rounded-md px-8",
				icon: "h-9 w-9",
			},
		},
		defaultVariants: {
			variant: "default",
			size: "default",
		},
	},
);

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

const Button = (
    {
        ref,
        className,
        variant,
        size,
        asChild = false,
        ...props
    }: ButtonProps & {
        ref: React.RefObject<HTMLButtonElement>;
    }
) => {
    const Comp = asChild ? Slot : "button";
    return (
        <Comp
            className={cn(buttonVariants({ variant, size, className }))}
            ref={ref}
            {...props}
        />
    );
};
Button.displayName = "Button";

export { Button, buttonVariants };