import { authFetch } from '../../../utils/authFetch'

export type SubscribeAboItem = { coffeeId: string | number; quantity?: number }
export type SubscribeAboInput = {
  coffeeId?: string | number // optional when items provided
  items?: SubscribeAboItem[] // NEW: whole order in one call
  billing_interval?: string
  interval_count?: number
  is_auto_renew?: boolean
  target_user_id?: number
  recipient_name?: string
  recipient_email?: string
  recipient_notes?: string
  // NEW: customer fields
  firstName?: string
  lastName?: string
  email?: string
  street?: string
  postalCode?: string
  city?: string
  country?: string
  frequency?: string
  startDate?: string
  // NEW: logged-in user id
  referred_by?: number
}

type Abonement = any
type HistoryEvent = any

const apiBase = (process.env.NEXT_PUBLIC_API_BASE_URL || '').replace(/\/+$/, '')

const parseJson = async (res: Response) => {
  const ct = res.headers.get('content-type') || ''
  const isJson = ct.includes('application/json')
  const json = isJson ? await res.json().catch(() => ({})) : null
  return { json, isJson }
}

export async function subscribeAbo(input: SubscribeAboInput) {
  const hasItems = Array.isArray(input.items) && input.items.length > 0
  if (!hasItems && !input.coffeeId) throw new Error('coffeeId is required')

  const hasRecipientFields = !!(input.recipient_name || input.recipient_email || input.recipient_notes)
  if (hasRecipientFields && !input.recipient_name) {
    throw new Error('recipient_name is required when gifting to a non-account recipient.')
  }

  // NEW: validate customer fields (required in UI)
  const requiredFields = ['firstName','lastName','email','street','postalCode','city','country','frequency','startDate'] as const
  const missing = requiredFields.filter(k => {
    const v = (input as any)[k]
    return typeof v !== 'string' || v.trim() === ''
  })
  if (missing.length) {
    throw new Error(`Missing required fields: ${missing.join(', ')}`)
  }

  const body: any = {
    billing_interval: input.billing_interval ?? 'month',
    interval_count: input.interval_count ?? 1,
    is_auto_renew: input.is_auto_renew ?? true,
    // NEW: include customer fields
    firstName: input.firstName,
    lastName: input.lastName,
    email: input.email,
    street: input.street,
    postalCode: input.postalCode,
    city: input.city,
    country: input.country?.toUpperCase?.() ?? input.country,
    frequency: input.frequency,
    startDate: input.startDate,
  }
  if (hasItems) {
    body.items = input.items!.map(i => ({
      coffeeId: i.coffeeId,
      quantity: i.quantity != null ? i.quantity : 1,
    }))
    // NEW: enforce exactly 12 packs
    const sumPacks = body.items.reduce((s: number, it: any) => s + Number(it.quantity || 0), 0)
    if (sumPacks !== 12) {
      console.warn('[subscribeAbo] Invalid pack total:', sumPacks, 'expected 12')
      throw new Error('Order must contain exactly 12 packs (120 capsules).')
    }
  } else {
    body.coffeeId = input.coffeeId
    // single-item legacy path — backend expects bundle, prefer items usage
  }
  // NEW: always include available recipient fields and target_user_id when provided
  if (input.target_user_id != null) body.target_user_id = input.target_user_id
  if (input.recipient_name) body.recipient_name = input.recipient_name
  if (input.recipient_email) body.recipient_email = input.recipient_email
  if (input.recipient_notes) body.recipient_notes = input.recipient_notes
  // NEW: always include referred_by if provided
  if (input.referred_by != null) body.referred_by = input.referred_by

  const url = `${apiBase}/api/abonements/subscribe`
  console.info('[subscribeAbo] POST', url, { body })
  // NEW: explicit JSON preview that matches the actual request body
  console.info('[subscribeAbo] Body JSON:', JSON.stringify(body))
  const res = await authFetch(url, {
    method: 'POST',
    headers: { 'Content-Type': 'application/json', Accept: 'application/json' },
    body: JSON.stringify(body),
    credentials: 'include',
  })
  const { json } = await parseJson(res)
  console.info('[subscribeAbo] Response', res.status, json)
  if (!res.ok || !json?.success) throw new Error(json?.message || `Subscribe failed: ${res.status}`)
  return json.data as Abonement
}

async function postAction(url: string) {
  const res = await authFetch(url, { method: 'POST', headers: { Accept: 'application/json' }, credentials: 'include' })
  const { json } = await parseJson(res)
  if (!res.ok || !json?.success) throw new Error(json?.message || `Request failed: ${res.status}`)
  return json.data as Abonement
}

export const pauseAbo = (id: string | number) => postAction(`${apiBase}/abonements/${id}/pause`)
export const resumeAbo = (id: string | number) => postAction(`${apiBase}/abonements/${id}/resume`)
export const cancelAbo = (id: string | number) => postAction(`${apiBase}/abonements/${id}/cancel`)
export const renewAbo = (id: string | number) => postAction(`${apiBase}/admin/abonements/${id}/renew`)

export async function getMyAbonements(status?: string) {
  const qs = status ? `?status=${encodeURIComponent(status)}` : ''
  const res = await authFetch(`${apiBase}/abonements/mine${qs}`, { method: 'GET', headers: { Accept: 'application/json' }, credentials: 'include' })
  const { json } = await parseJson(res)
  if (!res.ok || !json?.success) throw new Error(json?.message || `Fetch failed: ${res.status}`)
  return (json.data || []) as Abonement[]
}

export async function getAboHistory(id: string | number) {
  const res = await authFetch(`${apiBase}/abonements/${id}/history`, { method: 'GET', headers: { Accept: 'application/json' }, credentials: 'include' })
  const { json } = await parseJson(res)
  if (!res.ok || !json?.success) throw new Error(json?.message || `History failed: ${res.status}`)
  return (json.data || []) as HistoryEvent[]
}