/**
 * Packs de crédits IA (achat one-shot Stripe, mode payment).
 * Les crédits achetés s’ajoutent à `purchasedBalance` (reportables entre mois).
 */

import { getConfigValue } from '@/lib/config'
import { stripe } from '@/lib/stripe'

export type CreditPackId = 'S' | 'M' | 'L'

export type CreditPackDef = {
  id: CreditPackId
  credits: number
  /** Prix d’affichage par défaut (si Stripe non configuré) */
  defaultDisplay: string
  defaultAmount: number
  currency: string
  priceConfigKey: string
}

/** Catalogue fixe — crédits par pack (option M). */
export const CREDIT_PACKS: Record<CreditPackId, CreditPackDef> = {
  S: {
    id: 'S',
    credits: 100,
    defaultDisplay: '4,90 €',
    defaultAmount: 4.9,
    currency: 'EUR',
    priceConfigKey: 'STRIPE_PRICE_CREDITS_S',
  },
  M: {
    id: 'M',
    credits: 500,
    defaultDisplay: '19,90 €',
    defaultAmount: 19.9,
    currency: 'EUR',
    priceConfigKey: 'STRIPE_PRICE_CREDITS_M',
  },
  L: {
    id: 'L',
    credits: 2000,
    defaultDisplay: '49,90 €',
    defaultAmount: 49.9,
    currency: 'EUR',
    priceConfigKey: 'STRIPE_PRICE_CREDITS_L',
  },
}

export const CREDIT_PACK_IDS = Object.keys(CREDIT_PACKS) as CreditPackId[]

export function isCreditPackId(value: string): value is CreditPackId {
  return value === 'S' || value === 'M' || value === 'L'
}

export function getCreditPack(id: CreditPackId): CreditPackDef {
  return CREDIT_PACKS[id]
}

export async function resolvePackPriceId(packId: CreditPackId): Promise<string> {
  const pack = CREDIT_PACKS[packId]
  const fromDb = await getConfigValue(pack.priceConfigKey, '')
  const priceId = fromDb || process.env[pack.priceConfigKey] || ''
  if (priceId) return priceId

  const isMock =
    !process.env.STRIPE_SECRET_KEY || process.env.STRIPE_SECRET_KEY === 'sk_test_placeholder'
  if (isMock && process.env.NODE_ENV !== 'test') {
    return `price_mock_credits_${packId.toLowerCase()}`
  }
  throw new Error(`No Stripe price ID configured for credit pack ${packId}`)
}

export type PackPublicPrice = {
  id: CreditPackId
  credits: number
  display: string
  amount: number
  currency: string
  configured: boolean
}

function formatMoney(amount: number, currency: string): string {
  const cur = currency.toUpperCase()
  if (cur === 'EUR') {
    return `${amount.toLocaleString('fr-FR', { minimumFractionDigits: 0, maximumFractionDigits: 2 })} €`
  }
  if (cur === 'USD') {
    return `$${amount.toLocaleString('en-US', { minimumFractionDigits: 0, maximumFractionDigits: 2 })}`
  }
  if (cur === 'GBP') {
    return `£${amount.toLocaleString('en-GB', { minimumFractionDigits: 0, maximumFractionDigits: 2 })}`
  }
  return `${amount} ${cur}`
}

export async function getPackPublicPrices(): Promise<PackPublicPrice[]> {
  const isMock =
    !process.env.STRIPE_SECRET_KEY || process.env.STRIPE_SECRET_KEY === 'sk_test_placeholder'

  return Promise.all(
    CREDIT_PACK_IDS.map(async (id) => {
      const pack = CREDIT_PACKS[id]
      let display = pack.defaultDisplay
      let amount = pack.defaultAmount
      let currency = pack.currency
      let configured = false

      try {
        const priceId = await resolvePackPriceId(id)
        if (priceId && !priceId.startsWith('price_mock_')) {
          configured = true
          if (!isMock) {
            const price = await stripe.prices.retrieve(priceId)
            if (price.unit_amount != null) {
              amount = price.unit_amount / 100
              currency = price.currency.toUpperCase()
              display = formatMoney(amount, currency)
            }
          }
        }
      } catch {
        /* pack non configuré — on garde le prix catalogue */
      }

      return {
        id,
        credits: pack.credits,
        display,
        amount,
        currency,
        // true seulement si un vrai price_… est en admin/env (pas les mocks)
        configured,
      }
    }),
  )
}

/** Retrouve packId + crédits depuis un price ID Stripe (webhook). */
export async function resolvePackFromPriceId(
  priceId: string,
): Promise<{ packId: CreditPackId; credits: number } | null> {
  if (!priceId) return null
  if (priceId.startsWith('price_mock_credits_')) {
    const suffix = priceId.replace('price_mock_credits_', '').toUpperCase()
    if (isCreditPackId(suffix)) {
      return { packId: suffix, credits: CREDIT_PACKS[suffix].credits }
    }
  }

  for (const id of CREDIT_PACK_IDS) {
    const pack = CREDIT_PACKS[id]
    const fromDb = await getConfigValue(pack.priceConfigKey, '')
    const configured = fromDb || process.env[pack.priceConfigKey] || ''
    if (configured && configured === priceId) {
      return { packId: id, credits: pack.credits }
    }
  }
  return null
}