/**
 * Member Payment Management Composable
 * Handles payment setup and subscription creation for pending payment members
 */

export const useMemberPayment = () => {
  const { memberData, checkMemberStatus } = useAuth()
  const { initializeHelcimPay, verifyPayment, cleanup: cleanupHelcimPay } =
    useHelcimPay()

  const isProcessingPayment = ref(false)
  const paymentError = ref(null)
  const paymentSuccess = ref(false)

  const customerId = ref('')
  const customerCode = ref('')

  /**
   * Initiate payment setup for a member with pending_payment status
   * This is the main entry point called from "Complete Payment" buttons
   */
  const initiatePaymentSetup = async () => {
    isProcessingPayment.value = true
    paymentError.value = null
    paymentSuccess.value = false

    try {
      // Fast-path: when both Helcim ids are already cached on the member doc
      // AND a card's on file, we can skip the paid getOrCreateCustomer round
      // trip entirely and go straight to subscription creation.
      const hasCachedHelcimIds = Boolean(
        memberData.value?.helcimCustomerId && memberData.value?.helcimCustomerCode
      )

      let existing = null
      let probedExistingCard = false
      let cardToken = null

      if (hasCachedHelcimIds) {
        existing = await $fetch('/api/helcim/existing-card').catch((err) => {
          console.warn('[payment] existing-card lookup failed, falling back to verify flow:', err)
          return null
        })
        probedExistingCard = true
        if (existing?.cardToken) {
          customerId.value = memberData.value.helcimCustomerId
          customerCode.value = memberData.value.helcimCustomerCode
          cardToken = existing.cardToken
        }
      }

      if (!cardToken) {
        // Skip HelcimPay verify if a card's already on file — Helcim refuses
        // to re-save it, breaking retries after a partial-failed signup.
        const [, existingFromFull] = await Promise.all([
          getOrCreateCustomer(),
          probedExistingCard
            ? Promise.resolve(existing)
            : $fetch('/api/helcim/existing-card').catch((err) => {
                console.warn('[payment] existing-card lookup failed, falling back to verify flow:', err)
                return null
              }),
        ])

        cardToken = existingFromFull?.cardToken || null
      }

      if (!cardToken) {
        await initializeHelcimPay(
          customerId.value,
          customerCode.value,
          0,
        )

        const paymentResult = await verifyPayment()

        if (!paymentResult.success) {
          throw new Error('Payment verification failed')
        }

        const verifyResult = await $fetch('/api/helcim/verify-payment', {
          method: 'POST',
          body: {
            cardToken: paymentResult.cardToken,
            customerId: customerId.value,
          },
        })

        if (!verifyResult.success) {
          throw new Error('Payment verification failed on backend')
        }

        cardToken = paymentResult.cardToken
      }

      const subscriptionResponse = await $fetch('/api/helcim/subscription', {
        method: 'POST',
        body: {
          customerId: customerId.value,
          customerCode: customerCode.value,
          contributionAmount: memberData.value?.contributionAmount ?? 5,
          cardToken,
        },
      })

      if (!subscriptionResponse.success) {
        throw new Error('Subscription creation failed')
      }

      paymentSuccess.value = true
      await checkMemberStatus()

      // Clear success message after 3 seconds
      setTimeout(() => {
        paymentSuccess.value = false
      }, 3000)

      return {
        success: true,
        message: 'Payment completed successfully!',
      }
    } catch (error) {
      console.error('Payment setup error:', error)
      paymentError.value =
        error.message || 'Payment setup failed. Please try again.'
      throw error
    } finally {
      isProcessingPayment.value = false
      cleanupHelcimPay()
    }
  }

  /**
   * Get or create Helcim customer for member
   */
  const getOrCreateCustomer = async () => {
    try {
      if (!memberData.value?.helcimCustomerId) {
        // Create new customer
        const customerResponse = await $fetch(
          '/api/helcim/get-or-create-customer',
          {
            method: 'POST',
          },
        )

        customerId.value = customerResponse.customerId
        customerCode.value = customerResponse.customerCode

        console.log(
          'Created new Helcim customer:',
          customerId.value,
        )
      } else {
        // Get customer code from existing customer
        const customerResponse = await $fetch(
          '/api/helcim/customer-code',
        )
        customerId.value = customerResponse.customerId
        customerCode.value = customerResponse.customerCode

        console.log(
          'Using existing Helcim customer:',
          customerId.value,
        )
      }
    } catch (error) {
      console.error('Failed to get or create customer:', error)
      throw new Error('Failed to initialize payment. Please try again.')
    }
  }

  /**
   * Complete payment from status banner
   * Entry point for clicking "Complete Payment" from any page
   */
  const completePayment = async () => {
    try {
      await initiatePaymentSetup()
      return true
    } catch (error) {
      console.error('Payment failed:', error)
      return false
    }
  }

  const resetPaymentState = () => {
    isProcessingPayment.value = false
    paymentError.value = null
    paymentSuccess.value = false
  }

  return {
    isProcessingPayment: readonly(isProcessingPayment),
    paymentError: readonly(paymentError),
    paymentSuccess: readonly(paymentSuccess),
    initiatePaymentSetup,
    completePayment,
    resetPaymentState,
  }
}