import { useMemo } from 'react'
import { Link } from 'react-router-dom'
import PublicLayout from '../../components/PublicLayout.jsx'
import HeroElement from '../../components/HeroElement.jsx'
import { useSite } from '../../contexts/SiteContext.jsx'

const DEFAULT_HERO_IMAGE = '/assets/img/uomysticmoon-main-hero.png'
const HERO_BG =
  "linear-gradient(90deg,rgba(11,15,20,0.34) 0%,rgba(11,15,20,0.5) 36%,rgba(11,15,20,0.78) 62%,rgba(11,15,20,0.66) 100%),linear-gradient(180deg,rgba(11,15,20,0.08) 0%,rgba(11,15,20,0.72) 100%),url('" +
  DEFAULT_HERO_IMAGE +
  "')"

// Single-stop dark overlay driven by the editor's opacity slider.
function buildOverlay(opacity) {
  return `linear-gradient(180deg,rgba(11,15,20,${opacity * 0.15}) 0%,rgba(11,15,20,${opacity}) 100%)`
}

// The current hardcoded hero, expressed as a HeroLayout so the page is unchanged
// until staff publish their own. Font sizes use the existing clamp() strings so
// the default stays responsive (editor-created text uses px).
function defaultLayout(teaser) {
  return {
    version: 1,
    background: { image_url: null, position_x: 'left', position_y: 'center', size: 'cover' },
    overlay: { opacity: 0.72 },
    elements: [
      {
        id: 'default-text',
        type: 'text_block',
        x: 50,
        y: 42,
        z: 1,
        anchor: 'center',
        props: {
          align: 'center',
          width: 760,
          lines: [
            { text: 'Private shard project', tag: 'span', fontSize: '0.74rem', color: '#c2d2e6', weight: 700, letterSpacing: '0.22em', transform: 'uppercase', font: 'sans' },
            { text: 'UOMysticmoon', tag: 'h1', fontSize: 'clamp(3rem,8.5vw,5.75rem)', color: 'var(--head)', weight: 600, letterSpacing: '0.02em', lineHeight: 1, font: 'display', marginTop: 14 },
            { text: 'A private Ultima Online world in progress', tag: 'p', fontSize: '1.32rem', color: '#dbe2ea', italic: true, marginTop: 22 },
            { text: teaser, tag: 'p', fontSize: '1.06rem', color: '#c4cdd8', maxWidth: 600, marginTop: 22 },
          ],
        },
      },
      {
        id: 'default-buttons',
        type: 'buttons',
        x: 50,
        y: 72,
        z: 2,
        anchor: 'center',
        props: {
          align: 'center',
          gap: 12,
          items: [
            { label: 'Enter the Website', to: '/site', variant: 'primary' },
            { label: 'Open the Wiki', to: '/wiki', variant: 'ghost' },
          ],
        },
      },
    ],
  }
}

const QUICK = [
  { label: 'News', to: '/site/news' },
  { label: 'Screenshots', to: '/site/screenshots' },
  { label: 'Five on Friday', to: '/site/five-on-friday' },
  { label: 'Monthly Newsletter', to: '/site/newsletter' },
  { label: 'About', to: '/site/about' },
]

const DESTINATIONS = [
  {
    kicker: 'Public portal',
    title: 'Mysticmoon Website',
    body: 'Updates, screenshots, newsletters, and weekly community posts from the shard.',
    to: '/site',
  },
  {
    kicker: 'Knowledge base',
    title: 'Mysticmoon Wiki',
    body: 'Guides, maps, systems, items, monsters, crafting, lore, and rules.',
    to: '/wiki',
  },
]

export default function Portal() {
  const { settings } = useSite()
  const teaser =
    settings.homepage_teaser ||
    'Mysticmoon is still being shaped beneath a midnight sky — a quiet preview for the news, screenshots, guides, and community notes to come as the world wakes.'

  // Parse the published layout; fall back to the pre-populated default if missing,
  // malformed, the wrong version, or empty — so the hero is never blank.
  const parsed = useMemo(() => {
    try {
      const l = settings.hero_layout ? JSON.parse(settings.hero_layout) : null
      return l && l.version === 1 && Array.isArray(l.elements) && l.elements.length ? l : null
    } catch {
      return null
    }
  }, [settings.hero_layout])

  const layout = parsed || defaultLayout(teaser)
  const isDefault = !parsed
  const bg = layout.background || {}
  // Keep the exact multi-gradient look for the untouched default; otherwise build
  // from the editor's overlay opacity over the chosen (or default) image.
  const backgroundImage =
    isDefault && !bg.image_url
      ? HERO_BG
      : `${buildOverlay(layout.overlay?.opacity ?? 0.72)}, url('${bg.image_url || DEFAULT_HERO_IMAGE}')`
  const elements = [...layout.elements].sort((a, b) => (a.z || 0) - (b.z || 0))

  return (
    <PublicLayout header={false}>
      <main style={{ minHeight: '100vh', display: 'flex', flexDirection: 'column' }}>
        <section
          style={{
            position: 'relative',
            minHeight: 'clamp(600px,72vh,860px)',
            overflow: 'hidden',
            backgroundColor: 'var(--bg-deep)',
            backgroundImage,
            backgroundPosition: `${bg.position_x || 'left'} ${bg.position_y || 'center'}`,
            backgroundRepeat: 'no-repeat',
            backgroundSize: bg.size || 'cover',
          }}
        >
          <div style={{ position: 'absolute', inset: 0, padding: '0 max(18px,calc((100% - 1080px)/2))' }}>
            {elements.map((el) => (
              <HeroElement key={el.id} element={el} />
            ))}
          </div>
        </section>

        <div className="shell" style={{ padding: '56px 0 12px' }}>
          <nav className="grid-2" aria-label="Main destinations">
            {DESTINATIONS.map((d) => (
              <Link key={d.to} to={d.to} className="card" style={{ padding: 30 }}>
                <span className="card-kicker" style={{ letterSpacing: '0.16em', marginBottom: 14 }}>
                  {d.kicker}
                </span>
                <strong
                  className="display"
                  style={{ fontSize: '1.7rem', color: 'var(--head)', marginBottom: 10, fontWeight: 600 }}
                >
                  {d.title}
                </strong>
                <span className="muted">{d.body}</span>
              </Link>
            ))}
          </nav>
        </div>

        <div className="shell" style={{ padding: '24px 0 64px' }}>
          <nav style={{ display: 'flex', flexWrap: 'wrap', justifyContent: 'center', gap: 10 }} aria-label="Quick links">
            {QUICK.map((q) => (
              <Link key={q.to} to={q.to} className="pill">
                {q.label}
              </Link>
            ))}
          </nav>
        </div>
      </main>
    </PublicLayout>
  )
}
