import type { MetadataRoute } from 'next'

const siteUrl = process.env.NEXT_PUBLIC_SITE_URL

// In production, warn loudly but don't crash — the sitemap will use the
// fallback URL. Set NEXT_PUBLIC_SITE_URL in your deployment env to get the
// correct absolute URLs in sitemap.xml.
if (!siteUrl && process.env.NODE_ENV === 'production') {
  console.warn(
    '[sitemap] NEXT_PUBLIC_SITE_URL is not set — sitemap will use https://trumpsignal.com as fallback. ' +
    'Set this env var in your deployment to avoid incorrect sitemap URLs.',
  )
}

const base = (siteUrl || 'https://trumpsignal.com').replace(/\/$/, '')

const routes: Array<{
  path: string
  priority: number
  freq: MetadataRoute.Sitemap[number]['changeFrequency']
}> = [
  { path: '',              priority: 1.0, freq: 'hourly'  },
  { path: '/trump',        priority: 0.9, freq: 'hourly'  },
  { path: '/macro',          priority: 0.9, freq: 'daily'   },
  { path: '/kol',          priority: 0.9, freq: 'daily'   },
  { path: '/trades',       priority: 0.8, freq: 'daily'   },
  { path: '/analytics',    priority: 0.7, freq: 'daily'   },
  { path: '/methodology',  priority: 0.8, freq: 'monthly' },
  { path: '/glossary',     priority: 0.8, freq: 'monthly' },
  { path: '/case-studies', priority: 0.8, freq: 'monthly' },
  { path: '/settings',     priority: 0.5, freq: 'monthly' },
  { path: '/privacy',      priority: 0.3, freq: 'yearly'  },
  { path: '/terms',        priority: 0.3, freq: 'yearly'  },
  { path: '/contact',      priority: 0.4, freq: 'monthly' },
]

// i18n shelved — only emit English routes. Add 'zh' back when content is
// actually translated (otherwise Google flags duplicate content under hreflang).
const locales = ['en']

export default function sitemap(): MetadataRoute.Sitemap {
  const now = new Date()
  const entries: MetadataRoute.Sitemap = []

  // Root landing (not locale-scoped)
  entries.push({
    url: base,
    lastModified: now,
    changeFrequency: 'hourly',
    priority: 1.0,
  })

  for (const locale of locales) {
    for (const r of routes) {
      entries.push({
        url: `${base}/${locale}${r.path}`,
        lastModified: now,
        changeFrequency: r.freq,
        priority: r.priority,
      })
    }
  }

  return entries
}