import { authenticate } from '../../plugins/auth.js'
import { getCustomerById } from '../../services/customer.service.js'
import {
  requestPayment,
  confirmPaymentForCustomer,
  cancelPayment,
  getPayment,
  getCustomerPendingPayments,
} from '../../services/payment.service.js'
import {
  isCustomerEligibleForFirstSessionDiscount,
  isValidTier,
  findTier,
  readFirstSessionDiscountConfig,
} from '../../services/pricing.service.js'
import { getXenditConfig } from '../../services/config.service.js'
import { findActiveMethodByCode } from '../../services/payment-catalog.service.js'
import { UserType, SessionMode } from '../../constants.js'

const resolveCustomer = async (request, reply) => {
  if (request.auth?.userType !== UserType.CUSTOMER) {
    return reply.code(403).send({
      success: false,
      error: { code: 'FORBIDDEN', message: 'Customer account required' },
    })
  }
  const customer = await getCustomerById(request.auth.userId)
  if (!customer) {
    return reply.code(404).send({
      success: false,
      error: { code: 'ACCOUNT_NOT_FOUND', message: 'Customer account not found' },
    })
  }
  request.customer = customer
}

/**
 * Payment session lifecycle (mocked — no Xendit yet).
 *
 *   POST   /api/client/payment-requests
 *   POST   /api/client/payment-requests/:id/confirm
 *   POST   /api/client/payment-requests/:id/cancel
 *   GET    /api/client/payment-requests/:id
 */
export const clientPaymentRoutes = async (app) => {
  // Create a payment session (status = pending). First-session-discount is server-authoritative:
  // if the customer is eligible AND this is NOT an extension AND mode is in the configured
  // modes list, amount is forced to the configured discount price.
  app.post('/', { preHandler: [authenticate, resolveCustomer] }, async (request, reply) => {
    const {
      duration_minutes,
      mode = SessionMode.CHAT,
      targeted_mitra_id = null,
      is_extension = false,
      method = null,
    } = request.body ?? {}

    // Catalog validation — the customer's pre-pick (set in payment_method_screen.dart)
    // must reference an active row in `payment_methods`. Casing-tolerant; older app
    // versions sending lower-case (`qris`) are normalised inside the service.
    // `method` is optional for backwards compat with pre-Phase-5.x callers.
    // Amount-bound enforcement happens AFTER amount is computed below; we
    // capture `methodEntry` here to avoid a second lookup.
    let methodEntry = null
    if (method !== null && method !== undefined) {
      if (typeof method !== 'string' || method.trim().length === 0) {
        return reply.code(422).send({
          success: false,
          error: { code: 'VALIDATION_ERROR', message: 'method must be a non-empty string when provided' },
        })
      }
      methodEntry = await findActiveMethodByCode(method)
      if (!methodEntry) {
        return reply.code(422).send({
          success: false,
          error: {
            code: 'INVALID_PAYMENT_METHOD',
            message: 'Selected payment method is not available',
          },
        })
      }
    }

    if (typeof duration_minutes !== 'number' || duration_minutes <= 0) {
      return reply.code(422).send({
        success: false,
        error: { code: 'VALIDATION_ERROR', message: 'duration_minutes must be a positive number' },
      })
    }
    if (mode !== SessionMode.CHAT && mode !== SessionMode.CALL) {
      return reply.code(422).send({
        success: false,
        error: { code: 'VALIDATION_ERROR', message: 'mode must be chat or call' },
      })
    }

    let isFirstSessionDiscount = false
    let amount

    if (!is_extension) {
      const eligible = await isCustomerEligibleForFirstSessionDiscount(request.customer.id)
      if (eligible) {
        const discount = await readFirstSessionDiscountConfig()
        // Discount is mode-gated. With default config (modes: ['chat']) call-mode never
        // gets the discount even if the user is eligible.
        if (
          discount.enabled
          && discount.modes.includes(mode)
          && duration_minutes === discount.duration_minutes
        ) {
          isFirstSessionDiscount = true
          amount = discount.actual_price_idr
        }
      }
    }

    if (!isFirstSessionDiscount) {
      // Resolve amount from the configured tier list for the requested mode.
      const tier = await findTier({ mode, durationMinutes: duration_minutes })
      if (!tier) {
        return reply.code(400).send({
          success: false,
          error: { code: 'INVALID_TIER', message: 'No price tier matches the requested mode/duration' },
        })
      }
      amount = tier.price_idr
      if (!(await isValidTier({ mode, durationMinutes: duration_minutes, priceIdr: amount }))) {
        return reply.code(400).send({
          success: false,
          error: { code: 'INVALID_TIER', message: 'Invalid price tier selection' },
        })
      }
    }

    // Per-method amount bounds — defense in depth alongside the client's own
    // disabled-tile UX. A stale catalog cache on the client could let a request
    // through that the picker should have blocked. Bounds are inclusive.
    if (methodEntry) {
      if (methodEntry.min_amount != null && amount < methodEntry.min_amount) {
        return reply.code(422).send({
          success: false,
          error: {
            code: 'INVALID_PAYMENT_AMOUNT',
            message: 'Amount below the minimum for the selected payment method',
            details: { amount, min_amount: methodEntry.min_amount, max_amount: methodEntry.max_amount },
          },
        })
      }
      if (methodEntry.max_amount != null && amount > methodEntry.max_amount) {
        return reply.code(422).send({
          success: false,
          error: {
            code: 'INVALID_PAYMENT_AMOUNT',
            message: 'Amount above the maximum for the selected payment method',
            details: { amount, min_amount: methodEntry.min_amount, max_amount: methodEntry.max_amount },
          },
        })
      }
    }

    // Phase 5: payment.service.js handles the Xendit invoice creation internally
    // when XENDIT_ENABLED=true. The row comes back with xendit_invoice_url populated;
    // when off, invoice_url is null and the dev/Maestro stub plays the webhook role.
    const session = await requestPayment({
      productType: 'chat_session',
      customerId: request.customer.id,
      durationMinutes: duration_minutes,
      amount,
      isFirstSessionDiscount,
      isExtension: Boolean(is_extension),
      targetedMitraId: targeted_mitra_id || null,
      mode,
      preferredPaymentCode: method ? String(method).toUpperCase() : null,
    })

    return reply.code(201).send({
      success: true,
      data: {
        id: session.id,
        amount: session.amount,
        duration_minutes: session.duration_minutes,
        is_first_session_discount: session.is_first_session_discount,
        is_extension: session.is_extension,
        mode: session.mode,
        targeted_mitra_id: session.targeted_mitra_id,
        expires_at: session.expires_at,
        status: session.status,
        invoice_url: session.xendit_invoice_url ?? null,
      },
    })
  })

  app.post('/:id/confirm', { preHandler: [authenticate, resolveCustomer] }, async (request, reply) => {
    // Phase 5 D9: when Xendit is live, only the webhook can confirm. The dev/Maestro
    // stub at /internal/_test/force-confirm-payment bypasses this gate (internal listener).
    if (getXenditConfig().enabled) {
      return reply.code(403).send({
        success: false,
        error: { code: 'FORBIDDEN', message: 'Confirmation must come from Xendit webhook' },
      })
    }
    const session = await confirmPaymentForCustomer(request.params.id, request.customer.id)
    return reply.send({
      success: true,
      data: {
        id: session.id,
        status: session.status,
        confirmed_at: session.confirmed_at,
      },
    })
  })

  app.post('/:id/cancel', { preHandler: [authenticate, resolveCustomer] }, async (request, reply) => {
    const session = await cancelPayment(request.params.id, request.customer.id)
    return reply.send({
      success: true,
      data: {
        id: session.id,
        status: session.status,
      },
    })
  })

  // Phase 4 Stage 10 — Chat Tab Pembayaran feed. Static path; registered
  // before `/:id` so find-my-way matches this and not the wildcard.
  app.get('/pending', { preHandler: [authenticate, resolveCustomer] }, async (request, reply) => {
    const data = await getCustomerPendingPayments(request.customer.id)
    return reply.send({ success: true, data })
  })

  app.get('/:id', { preHandler: [authenticate, resolveCustomer] }, async (request, reply) => {
    const session = await getPayment(request.params.id)
    if (!session) {
      return reply.code(404).send({
        success: false,
        error: { code: 'NOT_FOUND', message: 'Payment request not found' },
      })
    }
    if (session.customer_id !== request.customer.id) {
      return reply.code(403).send({
        success: false,
        error: { code: 'FORBIDDEN', message: 'Payment request does not belong to this customer' },
      })
    }
    // Phase 5: surface chat_session_id (and status) when the server-driven pairing
    // subscriber has already started pairing for this confirmed payment. Lets the
    // app skip its legacy POST /chat/request call and just move to the searching state.
    const { getDb } = await import('../../db/client.js')
    const sqlClient = getDb()
    const [chat] = await sqlClient`
      SELECT id, status FROM chat_sessions WHERE payment_request_id = ${session.id} LIMIT 1
    `
    return reply.send({
      success: true,
      data: {
        ...session,
        chat_session_id: chat?.id ?? null,
        chat_session_status: chat?.status ?? null,
      },
    })
  })
}