const SETTINGS_URL = process.env.SETTINGS_URL || 'http://10.10.10.106:3080'
const SETTINGS_SECRET = process.env.SETTINGS_SECRET || ''

let _credsCache = null  // { creds, expires_at }

async function getWorkforceCreds() {
  if (_credsCache && Date.now() < _credsCache.expires_at) return _credsCache.creds
  const res = await fetch(`${SETTINGS_URL}/settings/api/internal/integration/workforce`, {
    headers: { Authorization: `Bearer ${SETTINGS_SECRET}` },
    signal: AbortSignal.timeout(5000),
  })
  if (!res.ok) throw new Error(`Failed to fetch Workforce credentials from settings: ${res.status}`)
  const creds = await res.json()
  if (!creds.bearer_token) throw new Error('Workforce bearer token not configured in settings')
  _credsCache = { creds, expires_at: Date.now() + 5 * 60_000 }
  return creds
}

async function wfFetch(path) {
  const creds = await getWorkforceCreds()
  const baseUrl = creds.base_url || 'https://my.workforce.com'
  const res = await fetch(`${baseUrl}${path}`, {
    headers: { Authorization: `Bearer ${creds.bearer_token}` },
    signal: AbortSignal.timeout(10000),
  })
  if (!res.ok) {
    const body = await res.text().catch(() => '')
    throw new Error(`Workforce API error ${res.status} at ${path}${body ? ': ' + body.slice(0, 200) : ''}`)
  }
  return res.json()
}

async function wfFetchPaged(path) {
  const results = []
  let page = 1
  while (true) {
    const sep = path.includes('?') ? '&' : '?'
    const data = await wfFetch(`${path}${sep}page=${page}&page_size=100`)
    const items = Array.isArray(data) ? data : (data.users ?? data.departments ?? data.teams ?? data.locations ?? [])
    results.push(...items)
    if (items.length < 100) break
    page++
  }
  return results
}

export async function findEmployeeByEmail(email) {
  const data = await wfFetch(`/api/v2/users?email=${encodeURIComponent(email)}`)
  const users = Array.isArray(data) ? data : (data.users ?? [])
  return users.length > 0 ? users[0] : null
}

export async function findEmployeeById(wfUserId) {
  try {
    const data = await wfFetch(`/api/v2/users/${wfUserId}`)
    return data?.id ? data : (data?.user ?? null)
  } catch {
    return null
  }
}

export async function getLocationsByIds(ids) {
  const results = await Promise.all(ids.map(async id => {
    try {
      const data = await wfFetch(`/api/v2/locations/${id}`)
      return { id: String(id), name: data.name ?? `Location ${id}`, short_name: data.short_name ?? null }
    } catch {
      return { id: String(id), name: `Location ${id}`, short_name: null }
    }
  }))
  return results
}

export async function getAllDepartments() {
  return wfFetchPaged('/api/v2/departments')
}

export async function getEmployeeDepartments(wfUserId) {
  const depts = await getAllDepartments()
  const id = String(wfUserId)
  return depts.filter(d => {
    const staff    = (d.staff    ?? []).map(String)
    const managers = (d.managers ?? []).map(String)
    return staff.includes(id) || managers.includes(id)
  })
}

export async function getSyncConfig() {
  const creds = await getWorkforceCreds()
  return {
    syncHours: parseFloat(creds.sync_hours ?? '6'),
    locationId: creds.location_id ? String(creds.location_id) : null,
  }
}

export function invalidateCache() {
  _credsCache = null
}