import type { AnchorHTMLAttributes, ButtonHTMLAttributes, ReactNode } from "react";
import { forwardRef } from "react";
import { cva, type VariantProps } from "class-variance-authority";
import { cn } from "@/shared/utils";
// Loading spinner removed - using inline spinner for buttons

const buttonVariants = cva(
  "inline-flex items-center justify-center rounded-md text-sm font-medium transition-colors focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-ring focus-visible:ring-offset-2 disabled:opacity-50 disabled:pointer-events-none ring-offset-background",
  {
    variants: {
      variant: {
        default: "bg-blue-600 text-white hover:bg-blue-700",
        destructive: "bg-red-600 text-white hover:bg-red-700",
        outline: "border border-gray-300 bg-white hover:bg-gray-50",
        secondary: "bg-gray-100 text-gray-900 hover:bg-gray-200",
        ghost: "hover:bg-gray-100",
        link: "underline-offset-4 hover:underline text-blue-600",
      },
      size: {
        default: "h-10 py-2 px-4",
        sm: "h-9 px-3 rounded-md",
        lg: "h-11 px-8 rounded-md",
      },
    },
    defaultVariants: {
      variant: "default",
      size: "default",
    },
  }
);

interface ButtonExtras {
  leftIcon?: ReactNode;
  rightIcon?: ReactNode;
  loading?: boolean;
  isLoading?: boolean;
  loadingText?: ReactNode;
}

type ButtonAsAnchorProps = {
  as: "a";
  href: string;
} & AnchorHTMLAttributes<HTMLAnchorElement> &
  VariantProps<typeof buttonVariants> &
  ButtonExtras;

type ButtonAsButtonProps = {
  as?: "button";
} & ButtonHTMLAttributes<HTMLButtonElement> &
  VariantProps<typeof buttonVariants> &
  ButtonExtras;

export type ButtonProps = ButtonAsAnchorProps | ButtonAsButtonProps;

const Button = forwardRef<HTMLButtonElement | HTMLAnchorElement, ButtonProps>((props, ref) => {
  const {
    leftIcon,
    rightIcon,
    loading: loadingProp,
    isLoading,
    loadingText,
    children,
    ...rest
  } = props;

  const loading = loadingProp ?? isLoading ?? false;

  if (props.as === "a") {
    const { className, variant, size, as: _as, href, ...anchorProps } = rest as ButtonAsAnchorProps;
    return (
      <a
        className={cn(buttonVariants({ variant, size, className }))}
        href={href}
        ref={ref as React.Ref<HTMLAnchorElement>}
        aria-busy={loading || undefined}
        {...anchorProps}
      >
        <span className="inline-flex items-center gap-2">
          {loading ? (
            <div className="animate-spin rounded-full h-4 w-4 border border-current border-t-transparent" />
          ) : leftIcon}
          <span>{loading ? loadingText ?? children : children}</span>
          {!loading && rightIcon ? <span className="ml-1">{rightIcon}</span> : null}
        </span>
      </a>
    );
  }

  const { className, variant, size, as: _as, disabled, ...buttonProps } = rest as ButtonAsButtonProps;
  return (
    <button
      className={cn(buttonVariants({ variant, size, className }))}
      ref={ref as React.Ref<HTMLButtonElement>}
      disabled={loading || disabled}
      aria-busy={loading || undefined}
      {...buttonProps}
    >
      <span className="inline-flex items-center gap-2">
        {loading ? (
          <div className="animate-spin rounded-full h-4 w-4 border border-current border-t-transparent" />
        ) : leftIcon}
        <span>{loading ? loadingText ?? children : children}</span>
        {!loading && rightIcon ? <span className="ml-1">{rightIcon}</span> : null}
      </span>
    </button>
  );
});
Button.displayName = "Button";

export { Button, buttonVariants };