import { NextResponse } from 'next/server'
import { getServerSession } from 'next-auth'
import { authOptions } from '@/lib/auth'

export async function GET() {
  const session = await getServerSession(authOptions)
  if (!session) return NextResponse.json({ error: 'Non authentifié' }, { status: 401 })

  const apiKey = process.env.GOOGLE_API_KEY
  const sheetId = process.env.GOOGLE_SHEETS_ID
  if (!apiKey || !sheetId) {
    return NextResponse.json({ error: 'GOOGLE_API_KEY et GOOGLE_SHEETS_ID requis' }, { status: 500 })
  }

  try {
    const url = `https://sheets.googleapis.com/v4/spreadsheets/${sheetId}?key=${apiKey}&fields=sheets.properties.title`
    const res = await fetch(url, { cache: 'no-store' })
    if (!res.ok) {
      const err = await res.text()
      throw new Error(`Google Sheets API error: ${res.status} — ${err}`)
    }
    const data = await res.json()
    const tabs: string[] = (data.sheets as Array<{ properties: { title: string } }>).map(
      (s) => s.properties.title,
    )
    return NextResponse.json({ tabs })
  } catch (err) {
    const message = err instanceof Error ? err.message : 'Erreur inconnue'
    return NextResponse.json({ error: message }, { status: 500 })
  }
}