import { useEffect, useRef, type ReactNode } from 'react';
import { cn } from '../lib/cn';

export interface ModalProps {
  open: boolean;
  onClose: () => void;
  title?: ReactNode;
  children?: ReactNode;
  footer?: ReactNode;
  size?: 'sm' | 'md' | 'lg' | 'xl';
  className?: string;
}

const sizeMap: Record<NonNullable<ModalProps['size']>, string> = {
  sm: 'max-w-sm',
  md: 'max-w-md',
  lg: 'max-w-2xl',
  xl: 'max-w-4xl',
};

export function Modal({
  open,
  onClose,
  title,
  children,
  footer,
  size = 'md',
  className,
}: ModalProps) {
  const dialogRef = useRef<HTMLDivElement>(null);

  useEffect(() => {
    if (!open) return;
    const onKey = (e: KeyboardEvent) => {
      if (e.key === 'Escape') onClose();
    };
    document.addEventListener('keydown', onKey);
    const prevOverflow = document.body.style.overflow;
    document.body.style.overflow = 'hidden';

    const node = dialogRef.current;
    const focusable = node?.querySelector<HTMLElement>(
      'button, [href], input, select, textarea, [tabindex]:not([tabindex="-1"])'
    );
    focusable?.focus();

    return () => {
      document.removeEventListener('keydown', onKey);
      document.body.style.overflow = prevOverflow;
    };
  }, [open, onClose]);

  if (!open) return null;

  return (
    <div
      className="fixed inset-0 z-50 flex items-center justify-center p-4"
      onClick={onClose}
      aria-hidden={false}
    >
      <div className="absolute inset-0 bg-text/40 backdrop-blur-sm" />
      <div
        ref={dialogRef}
        role="dialog"
        aria-modal="true"
        aria-labelledby={title ? 'modal-title' : undefined}
        onClick={(e) => e.stopPropagation()}
        className={cn(
          'relative w-full bg-surface border border-border rounded-2xl shadow-xl',
          sizeMap[size],
          className
        )}
      >
        {title && (
          <div className="flex items-center justify-between px-6 py-4 border-b border-border">
            <h2 id="modal-title" className="text-lg font-semibold text-text">{title}</h2>
            <button
              type="button"
              onClick={onClose}
              aria-label="Close"
              className="inline-flex h-8 w-8 items-center justify-center rounded-md text-text-3 hover:text-text hover:bg-surface-2 focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-primary-ring"
            >
              <svg width="16" height="16" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round">
                <line x1="18" y1="6" x2="6" y2="18" />
                <line x1="6" y1="6" x2="18" y2="18" />
              </svg>
            </button>
          </div>
        )}
        <div className="px-6 py-5 text-text-2">{children}</div>
        {footer && (
          <div className="flex items-center justify-end gap-2 px-6 py-4 border-t border-border bg-surface-2 rounded-b-2xl">
            {footer}
          </div>
        )}
      </div>
    </div>
  );
}