import type { ComponentType, ReactNode } from 'react';
import { Link } from 'react-router-dom';
import { cn } from '@/lib/utils';

/**
 * Shared empty-state component.
 *
 * Before this existed the app had ~39 ad-hoc empty states, each free to drift
 * in spacing, tone and — crucially — whether they offered a way *out*. The
 * `action` slot is the valuable part: "No crews nearby → Create one" turns a
 * dead-end into a loop. Prefer this component over hand-rolling new ones.
 */

export interface EmptyStateAction {
  /** Button label. */
  label: string;
  /** Internal route to navigate to (renders a <Link>). */
  to?: string;
  /** Click handler (renders a <button>). Ignored if `to` is set. */
  onClick?: () => void;
  /** Optional leading icon for the action button. */
  icon?: ComponentType<{ className?: string }>;
  /** Visual emphasis. `primary` = filled brand button, `secondary` = outline. */
  variant?: 'primary' | 'secondary';
  /** Extra classes for bespoke accent colors (e.g. teal crews, lime spots). */
  className?: string;
}

export interface EmptyStateProps {
  /** Lucide-style icon component rendered in the header tile. */
  icon?: ComponentType<{ className?: string }>;
  /** Emoji alternative to `icon` (used by some sections, e.g. 🛹). */
  emoji?: string;
  /** Headline. Kept short and human. */
  title: string;
  /** One or two sentences of guidance. */
  hint?: ReactNode;
  /** Primary + optional secondary actions. First is the emphasized CTA. */
  actions?: EmptyStateAction[];
  /** Optional footer link (e.g. "Have questions? Check the FAQ →"). */
  footer?: { label: string; to: string };
  /** Extra classes on the outer wrapper. */
  className?: string;
}

function ActionButton({ action }: { action: EmptyStateAction }) {
  const Icon = action.icon;
  const isPrimary = action.variant !== 'secondary';

  const classes = cn(
    'inline-flex w-full items-center justify-center gap-2 rounded-xl px-5 py-2.5 text-sm font-black uppercase tracking-wide transition-all active:scale-95 sm:w-auto',
    isPrimary
      ? 'bg-primary text-primary-foreground hover:bg-primary/90'
      : 'border border-border bg-white/5 text-foreground hover:bg-white/10',
    action.className,
  );

  const inner = (
    <>
      {Icon && <Icon className="h-4 w-4" />}
      {action.label}
    </>
  );

  if (action.to) {
    // Single interactive element — a <button> nested in a <Link> was invalid
    // and double-focusable for assistive tech.
    return (
      <Link to={action.to} className={classes}>
        {inner}
      </Link>
    );
  }

  return (
    <button type="button" onClick={action.onClick} className={classes}>
      {inner}
    </button>
  );
}

export function EmptyState({
  icon: Icon,
  emoji,
  title,
  hint,
  actions,
  footer,
  className,
}: EmptyStateProps) {
  return (
    <div
      className={cn(
        'flex flex-col items-center justify-center px-4 py-16 text-center',
        className,
      )}
    >
      {(Icon || emoji) && (
        <div className="mb-4 flex h-16 w-16 items-center justify-center rounded-2xl bg-white/5 text-3xl">
          {emoji ? (
            <span aria-hidden="true">{emoji}</span>
          ) : (
            Icon && <Icon className="h-8 w-8 text-muted-foreground" />
          )}
        </div>
      )}

      <h3 className="mb-2 text-lg font-black text-foreground">{title}</h3>

      {hint && (
        <p className="mb-6 max-w-xs text-sm text-muted-foreground">{hint}</p>
      )}

      {actions && actions.length > 0 && (
        <div className="flex flex-col gap-2 sm:flex-row sm:justify-center">
          {actions.map((action) => (
            <ActionButton key={action.label} action={action} />
          ))}
        </div>
      )}

      {footer && (
        <Link
          to={footer.to}
          className="mt-5 text-xs text-muted-foreground underline underline-offset-2 transition-colors hover:text-foreground"
        >
          {footer.label}
        </Link>
      )}
    </div>
  );
}

export default EmptyState;