import { auth } from '@/lib/auth'
import { supabaseAdmin } from '@/lib/supabaseAdmin'
import Link from 'next/link'

function timeAgo(iso: string) {
  const diffMs = Date.now() - new Date(iso).getTime()
  const mins = Math.floor(diffMs / 60000)
  if (mins < 1) return 'az önce'
  if (mins < 60) return `${mins} dk önce`
  const hours = Math.floor(mins / 60)
  if (hours < 24) return `${hours} sa önce`
  const days = Math.floor(hours / 24)
  return `${days} gün önce`
}

export default async function AdminDashboardPage() {
  const session = await auth()

  const now = new Date().toISOString()
  const sevenDaysAgo = new Date(Date.now() - 7 * 24 * 60 * 60 * 1000).toISOString()
  const oneDayAgo = new Date(Date.now() - 24 * 60 * 60 * 1000).toISOString()

  const [
    { count: totalUsers },
    { count: activeLicenses },
    { count: trialExpiringSoon },
    { count: crashes24h },
    { data: recentCrashes },
    { data: recentLicenseEvents },
  ] = await Promise.all([
    supabaseAdmin.from('profiles').select('id', { count: 'exact', head: true }),
    supabaseAdmin.from('licenses').select('id', { count: 'exact', head: true }).eq('status', 'active'),
    supabaseAdmin.from('profiles').select('id', { count: 'exact', head: true }).eq('license_status', 'trial').gte('trial_end_date', now).lte('trial_end_date', new Date(Date.now() + 3 * 24 * 60 * 60 * 1000).toISOString()),
    supabaseAdmin.from('crash_reports').select('id', { count: 'exact', head: true }).gte('created_at', oneDayAgo),
    supabaseAdmin.from('crash_reports').select('id, error_message, severity, app_version, created_at').order('created_at', { ascending: false }).limit(5),
    supabaseAdmin.from('license_events').select('id, event_type, license_id, created_at').order('created_at', { ascending: false }).limit(5),
  ])

  const activity = [
    ...(recentCrashes || []).map((c) => ({ id: c.id, text: `Hata: ${c.error_message || c.severity} (v${c.app_version})`, created_at: c.created_at, tone: 'danger' as const })),
    ...(recentLicenseEvents || []).map((e) => ({ id: e.id, text: `Lisans olayı: ${e.event_type}`, created_at: e.created_at, tone: 'neutral' as const })),
  ].sort((a, b) => new Date(b.created_at).getTime() - new Date(a.created_at).getTime()).slice(0, 8)

  const stats = [
    { name: 'Toplam Kullanıcı', stat: totalUsers ?? 0, href: '/admin/users' },
    { name: 'Aktif Lisans', stat: activeLicenses ?? 0, href: '/admin/licenses' },
    { name: 'Denemesi 3 Gün İçinde Bitecek', stat: trialExpiringSoon ?? 0, href: '/admin/users' },
    { name: 'Son 24 Saatte Hata', stat: crashes24h ?? 0, href: '/admin/logs' },
  ]

  return (
    <div className="space-y-6">
      <div>
        <h2 className="text-2xl font-bold tracking-tight text-gray-900 dark:text-white">Dashboard</h2>
        <p className="text-gray-500 dark:text-gray-400 mt-2">
          Hoş geldiniz, {session?.user?.name || session?.user?.email}. İşte AyrisLegal&apos;ın canlı durumu.
        </p>
      </div>

      <div className="grid grid-cols-1 gap-4 sm:grid-cols-2 lg:grid-cols-4">
        {stats.map((item) => (
          <Link
            key={item.name}
            href={item.href}
            className="overflow-hidden rounded-lg bg-white dark:bg-gray-950 border border-gray-200 dark:border-gray-800 px-4 py-5 shadow-sm sm:p-6 hover:border-gray-300 dark:hover:border-gray-700 transition-colors"
          >
            <dt className="truncate text-sm font-medium text-gray-500 dark:text-gray-400">{item.name}</dt>
            <dd className="mt-1 text-3xl font-semibold tracking-tight text-gray-900 dark:text-white">
              {item.stat}
            </dd>
          </Link>
        ))}
      </div>

      <div className="rounded-lg bg-white dark:bg-gray-950 border border-gray-200 dark:border-gray-800 shadow-sm">
        <div className="p-6">
          <h3 className="text-lg font-medium text-gray-900 dark:text-white">Son Aktiviteler</h3>
          <div className="mt-4 border-t border-gray-100 dark:border-gray-800">
            {activity.length === 0 ? (
              <div className="py-4 text-sm text-gray-500">Henüz aktivite kaydı bulunmuyor.</div>
            ) : (
              activity.map((a) => (
                <div key={a.id} className="py-3 border-b border-gray-100 dark:border-gray-800 last:border-0 flex items-center justify-between gap-4">
                  <span className={`text-sm ${a.tone === 'danger' ? 'text-red-600 dark:text-red-400' : 'text-gray-700 dark:text-gray-300'}`}>{a.text}</span>
                  <span className="text-xs text-gray-400 whitespace-nowrap">{timeAgo(a.created_at)}</span>
                </div>
              ))
            )}
          </div>
        </div>
      </div>
    </div>
  )
}