import { NOTIFICATION_EVENTS } from '../../../shared/constants/notification-events.js'
import { prisma } from '../lib/prisma.js'
import { createPayment, buildReceipt, getPayment } from '../lib/yookassa.js'

export async function registerUserPaymentRoutes(fastify) {
  fastify.post('/api/me/orders/:id/pay', { preHandler: [fastify.authenticate] }, async (request, reply) => {
    const userId = request.user.sub
    const userEmail = request.user.email

    if (!userEmail) {
      return reply.code(422).send({ error: 'Для онлайн-оплаты необходим email в профиле' })
    }

    const { id } = request.params

    const order = await prisma.order.findFirst({
      where: { id, userId },
      include: { items: true },
    })
    if (!order) return reply.code(404).send({ error: 'Заказ не найден' })

    if (order.paymentMethod === 'on_pickup') {
      return reply.code(409).send({
        error: 'Для этого заказа оплата при получении — онлайн-оплата недоступна',
      })
    }

    if (order.status !== 'PENDING_PAYMENT') {
      return reply.code(409).send({ error: 'Сейчас нельзя выполнить оплату для этого заказа' })
    }

    if (!order.deliveryFeeLocked) {
      return reply.code(409).send({
        error: 'Стоимость доставки ещё утверждается — оплата станет доступна позже',
      })
    }

    const existingPayment = await prisma.payment.findFirst({
      where: {
        orderId: id,
        status: { in: ['pending', 'waiting_for_capture'] },
        OR: [{ expiresAt: null }, { expiresAt: { gt: new Date() } }],
      },
      orderBy: { createdAt: 'desc' },
    })

    if (existingPayment && existingPayment.confirmationUrl) {
      return { confirmationUrl: existingPayment.confirmationUrl }
    }

    const idempotencyKey = `${id}-${Date.now()}`
    const returnUrl = `${process.env.CLIENT_PUBLIC_URL || 'http://127.0.0.1:5173'}/me/orders/${id}?paid=1`
    const clientIp = request.ip

    const amount = {
      value: (order.totalCents / 100).toFixed(2),
      currency: order.currency,
    }

    const receipt = buildReceipt({
      orderItems: order.items,
      deliveryFeeCents: order.deliveryFeeCents,
        userEmail: userEmail,
    })

    let result
    try {
      result = await createPayment({
        amount,
        description: `Оплата заказа №${order.id.slice(-6)}`,
        receipt,
        confirmation: { type: 'redirect', return_url: returnUrl },
        metadata: { orderId: order.id },
        idempotencyKey,
        clientIp,
      })
    } catch (err) {
      request.log.error({ err, orderId: id }, 'YooKassa createPayment failed')
      return reply.code(502).send({
        error: 'Не удалось создать платёж. Платёжный сервис временно недоступен.',
      })
    }

    await prisma.payment.create({
      data: {
        orderId: order.id,
        yookassaPaymentId: result.paymentId,
        status: result.status,
        amountCents: order.totalCents,
        currency: order.currency,
        confirmationUrl: result.confirmationUrl,
        expiresAt: result.expiresAt ? new Date(result.expiresAt) : null,
      },
    })

    return { confirmationUrl: result.confirmationUrl }
  })

  fastify.get('/api/me/orders/:orderId/payment', { preHandler: [fastify.authenticate] }, async (request, reply) => {
    const userId = request.user.sub
    const { orderId } = request.params

    const order = await prisma.order.findFirst({ where: { id: orderId, userId } })
    if (!order) return reply.code(404).send({ error: 'Заказ не найден' })

    const payment = await prisma.payment.findFirst({
      where: { orderId },
      orderBy: { createdAt: 'desc' },
    })
    if (!payment) {
      return { status: null, paid: false }
    }

    if (payment.status === 'succeeded' || payment.status === 'canceled') {
      return { status: payment.status, paid: payment.status === 'succeeded' }
    }

    try {
      const ykPayment = await getPayment(payment.yookassaPaymentId)

      if (ykPayment.status !== payment.status) {
        await prisma.payment.update({
          where: { id: payment.id },
          data: { status: ykPayment.status },
        })

        if (ykPayment.status === 'succeeded' && order.status === 'PENDING_PAYMENT') {
          const updated = await prisma.order.updateMany({
            where: { id: orderId, status: 'PENDING_PAYMENT' },
            data: { status: 'PAID' },
          })
          if (updated.count > 0) {
            request.server.eventBus.emit(NOTIFICATION_EVENTS.PAYMENT_STATUS_CHANGED, {
              orderId,
              userId: order.userId,
              paymentStatus: 'paid',
            })
          }
        }
      }

      return { status: ykPayment.status, paid: ykPayment.paid }
    } catch {
      return { status: payment.status, paid: payment.status === 'succeeded' }
    }
  })
}