import React, { CSSProperties, useState } from 'react';
import { useNode, UserComponent } from '@craftjs/core';
import { cssPropsToString } from '../../utils/style-helpers';
import { escapeHtml, escapeAttr, safeUrl, scopeId, cssValue } from '../../utils/escape';
import { tokenRef } from '../../utils/tokens';
import { NavLink, DROPDOWN_TOGGLE_ONCLICK, hasDropdown } from '../../utils/nav-links';

/* ---------- Types ---------- */

type MenuLink = NavLink;

interface MenuProps {
  links?: MenuLink[];
  /** #53: links follow the site's pages (materialised by PageContext). */
  followPages?: boolean;
  alignment?: 'left' | 'center' | 'right';
  linkColor?: string;
  linkHoverColor?: string;
  ctaBgColor?: string;
  ctaTextColor?: string;
  gap?: string;
  orientation?: 'horizontal' | 'vertical';
  fontSize?: string;
  style?: CSSProperties;
  hideOnDesktop?: boolean;
  hideOnTablet?: boolean;
  hideOnMobile?: boolean;
  animation?: string;
  animationDelay?: string;
}

/* ---------- Defaults ---------- */

const defaultLinks: MenuLink[] = [
  { text: 'Home', href: '/' },
  { text: 'About', href: '#about' },
  { text: 'Services', href: '#services' },
  { text: 'Contact', href: '#contact', isCta: true },
];

/* ---------- Component ---------- */

export const Menu: UserComponent<MenuProps> = ({
  links = defaultLinks,
  alignment = 'right',
  linkColor = '#3f3f46',
  linkHoverColor = tokenRef('primary'),
  ctaBgColor = tokenRef('primary'),
  ctaTextColor = '#ffffff',
  gap = '24px',
  orientation = 'horizontal',
  fontSize = '14px',
  style = {},
}) => {
  const {
    connectors: { connect, drag },
  } = useNode();

  const [hoveredLink, setHoveredLink] = useState<number | null>(null);
  const [openDropdown, setOpenDropdown] = useState<number | null>(null);

  const justifyMap = { left: 'flex-start', center: 'center', right: 'flex-end' };

  return (
    <nav
      ref={(ref: HTMLElement | null): void => { if (ref) connect(drag(ref)); }}
      style={{
        display: 'flex',
        flexDirection: orientation === 'vertical' ? 'column' : 'row',
        alignItems: orientation === 'vertical' ? (alignment === 'center' ? 'center' : alignment === 'right' ? 'flex-end' : 'flex-start') : 'center',
        justifyContent: orientation === 'horizontal' ? justifyMap[alignment] : undefined,
        gap,
        flexWrap: 'wrap',
        ...style,
      }}
    >
      {links.map((link, i) => {
        const kids = !link.isCta && link.children?.length ? link.children : null;
        const anchor = (
        <a
          key={i}
          href={link.href}
          target={link.isExternal ? '_blank' : undefined}
          rel={link.isExternal ? 'noopener noreferrer' : undefined}
          download={link.download || undefined}
          onClick={(e) => e.preventDefault()}
          onMouseEnter={() => setHoveredLink(i)}
          onMouseLeave={() => setHoveredLink(null)}
          style={{
            textDecoration: 'none',
            fontSize,
            fontWeight: link.isCta ? '600' : '400',
            color: link.isCta
              ? ctaTextColor
              : (hoveredLink === i ? linkHoverColor : linkColor),
            backgroundColor: link.isCta ? ctaBgColor : 'transparent',
            padding: link.isCta ? '8px 20px' : '0',
            borderRadius: link.isCta ? '6px' : '0',
            transition: 'color 0.15s, background-color 0.15s',
            ...(link.isCta && hoveredLink === i ? { filter: 'brightness(1.1)' } : {}),
          }}
        >
          {link.text}
        </a>
        );
        if (!kids) return anchor;
        // #53: one-level dropdown, opened on hover in the editor (export: hover,
        // focus-within and a click toggle -- see toHtml).
        return (
          <span
            key={i}
            style={{ position: 'relative', display: 'inline-flex', alignItems: 'center', gap: 4 }}
            onMouseEnter={() => setOpenDropdown(i)}
            onMouseLeave={() => setOpenDropdown(null)}
          >
            {anchor}
            <span aria-hidden="true" style={{ fontSize, color: linkColor }}>▾</span>
            {(openDropdown === i || orientation === 'vertical') && (
              <ul style={orientation === 'vertical' ? SUB_STATIC_STYLE : SUB_STYLE}>
                {kids.map((child, j) => (
                  <li key={j}>
                    <a
                      href={child.href}
                      onClick={(e) => e.preventDefault()}
                      style={{ display: 'block', padding: '6px 16px', whiteSpace: 'nowrap', textDecoration: 'none', fontSize, color: linkColor }}
                    >
                      {child.text}
                    </a>
                  </li>
                ))}
              </ul>
            )}
          </span>
        );
      })}
    </nav>
  );
};

const SUB_STYLE: CSSProperties = {
  position: 'absolute', top: '100%', left: 0, zIndex: 1001, minWidth: 180, margin: 0, padding: '8px 0',
  listStyle: 'none', background: 'var(--wsb-bg, #ffffff)', borderRadius: 6, boxShadow: '0 8px 24px rgba(0,0,0,0.12)',
};
const SUB_STATIC_STYLE: CSSProperties = { margin: 0, padding: '4px 0 0 12px', listStyle: 'none' };

/* ---------- Craft config ---------- */

Menu.craft = {
  displayName: 'Menu',
  props: {
    links: defaultLinks,
    followPages: false,
    alignment: 'right',
    linkColor: '#3f3f46',
    linkHoverColor: tokenRef('primary'),
    ctaBgColor: tokenRef('primary'),
    ctaTextColor: '#ffffff',
    gap: '24px',
    orientation: 'horizontal',
    fontSize: '14px',
    style: {},
    hideOnDesktop: false,
    hideOnTablet: false,
    hideOnMobile: false,
    animation: 'none',
    animationDelay: '0',
  } as MenuProps,
  rules: {
    canDrag: () => true,
    canMoveIn: () => false,
    canMoveOut: () => true,
  },
};

/* ---------- HTML export ---------- */

(Menu as any).toHtml = (props: MenuProps, _childrenHtml: string, nodeId?: string) => {
  // Sanitized once here -- linkCol/hoverCol/ctaBg/ctaText/gap/fSize are raw
  // string-interpolation sinks below (hoverCol goes into a <style> block,
  // the worst case: </style> breakout -> arbitrary <script>), see
  // task-cssxss-brief.md.
  const linkCol = cssValue(props.linkColor) || '#3f3f46';
  const hoverCol = cssValue(props.linkHoverColor) || tokenRef('primary');
  const ctaBg = cssValue(props.ctaBgColor) || tokenRef('primary');
  const ctaText = cssValue(props.ctaTextColor) || '#ffffff';
  const gap = cssValue(props.gap) || '24px';
  const orientation = props.orientation || 'horizontal';
  const alignment = props.alignment || 'right';
  const fSize = cssValue(props.fontSize) || '14px';

  const justifyMap: Record<string, string> = { left: 'flex-start', center: 'center', right: 'flex-end' };

  const navStyle = cssPropsToString({
    display: 'flex',
    flexDirection: orientation === 'vertical' ? 'column' : 'row',
    alignItems: orientation === 'vertical'
      ? (alignment === 'center' ? 'center' : alignment === 'right' ? 'flex-end' : 'flex-start')
      : 'center',
    justifyContent: orientation === 'horizontal' ? justifyMap[alignment] : undefined,
    gap,
    flexWrap: 'wrap',
    ...props.style,
  });

  const links = props.links || defaultLinks;

  // Scope for the hover CSS classes below. Deterministic AND unique: scoped
  // on the Craft node id so two Menu instances with identical/default links
  // don't collide on the same `.menu-link`/`.menu-cta` class names (which
  // would let one instance's hover styling bleed into the other's).
  const scope = scopeId(nodeId, JSON.stringify(links) + orientation + alignment, 'menu');

  const anchorHtml = (link: MenuLink) => {
    const target = link.isExternal ? ' target="_blank" rel="noopener noreferrer"' : '';
    const downloadAttr = link.download ? ' download' : '';
    const cls = link.isCta ? `${scope}-cta` : `${scope}-link`;
    const linkStyle = cssPropsToString({
      textDecoration: 'none',
      fontSize: fSize,
      fontWeight: link.isCta ? '600' : '400',
      color: link.isCta ? ctaText : linkCol,
      backgroundColor: link.isCta ? ctaBg : 'transparent',
      padding: link.isCta ? '8px 20px' : '0',
      borderRadius: link.isCta ? '6px' : '0',
      transition: 'color 0.15s, background-color 0.15s',
    });
    return `<a href="${escapeAttr(safeUrl(link.href || '#'))}" class="${cls}"${target}${downloadAttr}${linkStyle ? ` style="${linkStyle}"` : ''}>${escapeHtml(link.text)}</a>`;
  };

  // #53: a (non-CTA) link with children becomes a dropdown: the parent link
  // still navigates; a separate toggle button opens the submenu on touch /
  // click (hover and focus-within open it on desktop, see dropdownCss).
  const linksHtml = links.map((link) => {
    if (link.isCta || !link.children?.length) return anchorHtml(link);
    const kids = link.children.map((child) => `<li>${anchorHtml({ ...child, isCta: false })}</li>`).join('');
    return `<div class="${scope}-dd">${anchorHtml(link)}<button type="button" class="${scope}-dd-toggle" aria-haspopup="true" aria-expanded="false" aria-label="${escapeAttr(`${link.text} submenu`)}" onclick="${DROPDOWN_TOGGLE_ONCLICK}">&#9662;</button><ul class="${scope}-sub">${kids}</ul></div>`;
  }).join('\n    ');

  const dropdownCss = hasDropdown(links) ? `
  .${scope}-dd { position: relative; display: inline-flex; align-items: center; gap: 2px; }
  .${scope}-dd-toggle { background: none; border: 0; margin: 0; padding: 2px 4px; cursor: pointer; color: ${linkCol}; font-size: ${fSize}; line-height: 1; }
  .${scope}-sub { display: none; position: absolute; top: 100%; left: 0; z-index: 1001; min-width: 180px; margin: 0; padding: 8px 0; list-style: none; background: ${tokenRef('bg')}; border-radius: 6px; box-shadow: 0 8px 24px rgba(0,0,0,0.12); }
  .${scope}-dd:hover > .${scope}-sub, .${scope}-dd:focus-within > .${scope}-sub, .${scope}-dd.is-open > .${scope}-sub { display: block; }
  .${scope}-sub a { display: block !important; padding: 6px 16px !important; white-space: nowrap; }${orientation === 'vertical' ? `
  .${scope}-dd { flex-wrap: wrap; }
  .${scope}-sub { display: block; position: static; box-shadow: none; background: transparent; min-width: 0; padding: 4px 0 0 12px; flex-basis: 100%; }
  .${scope}-dd-toggle { display: none; }` : ''}` : '';

  const hoverCss = `<style>
  .${scope}-link:hover { color: ${hoverCol} !important; }
  .${scope}-cta:hover { filter: brightness(1.1); }${dropdownCss}
</style>`;

  return {
    html: `${hoverCss}
<nav${navStyle ? ` style="${navStyle}"` : ''}>
    ${linksHtml}
</nav>`,
  };
};