// Create a Helcim subscription
import { getHelcimPlanId, requiresPayment } from '../../config/contributions.js'
import Member from '../../models/member.js'
import { connectDB } from '../../utils/mongoose.js'
import { getSlackService } from '../../utils/slack.ts'
import { requireAuth, getPaymentBridgeMember } from '../../utils/auth.js'
import { createHelcimSubscription, generateIdempotencyKey, listHelcimCustomerTransactions } from '../../utils/helcim.js'
import { sendWelcomeEmail } from '../../utils/resend.js'
import { upsertPaymentFromHelcim } from '../../utils/payments.js'

// Function to invite member to Slack
async function inviteToSlack(member) {
  try {
    const slackService = getSlackService()
    if (!slackService) {
      console.warn('Slack service not configured, skipping invitation')
      return
    }

    console.log(`Processing Slack invitation for ${member.email}...`)
    
    const inviteResult = await slackService.inviteUserToSlack(
      member.email,
      member.name
    )

    if (inviteResult.success) {
      const update = {}
      if (inviteResult.status === 'existing_user_added_to_channel' ||
          inviteResult.status === 'user_already_in_channel' ||
          inviteResult.status === 'new_user_invited_to_workspace') {
        update.slackInviteStatus = 'sent'
        update.slackUserId = inviteResult.userId
        update.slackInvited = true
      } else {
        update.slackInviteStatus = 'pending'
        update.slackInvited = false
      }
      await Member.findByIdAndUpdate(
        member._id,
        { $set: update },
        { runValidators: false }
      )

      // Send notification to vetting channel
      await slackService.notifyNewMember(
        member.name,
        member.email,
        member.circle,
        member.contributionAmount,
        inviteResult.status
      )

      console.log(`Successfully processed Slack invitation for ${member.email}: ${inviteResult.status}`)
    } else {
      await Member.findByIdAndUpdate(
        member._id,
        { $set: { slackInviteStatus: 'failed' } },
        { runValidators: false }
      )

      console.error(`Failed to process Slack invitation for ${member.email}: ${inviteResult.error}`)
      // Don't throw error - subscription creation should still succeed
    }
  } catch (error) {
    console.error('Error during Slack invitation process:', error)

    try {
      await Member.findByIdAndUpdate(
        member._id,
        { $set: { slackInviteStatus: 'failed' } },
        { runValidators: false }
      )
    } catch (saveError) {
      console.error('Failed to update member Slack status:', saveError)
    }
    
    // Don't throw error - subscription creation should still succeed
  }
}

export default defineEventHandler(async (event) => {
  try {
    // Membership signup completes subscription before email verify; allow the
    // payment-bridge cookie set by /api/helcim/customer to satisfy auth here.
    const bridgeMember = await getPaymentBridgeMember(event)
    if (!bridgeMember) {
      await requireAuth(event)
    }
    await connectDB()
    const body = await validateBody(event, helcimSubscriptionSchema)

    // Check if payment is required
    if (!requiresPayment(body.contributionAmount)) {
      // For free tier, atomically capture pre-update status alongside the write.
      // Welcome email only fires on pending_payment → active transitions, not
      // on tier upgrades (active → active).
      const preMember = await Member.findOneAndUpdate(
        { helcimCustomerId: body.customerId },
        {
          status: 'active',
          contributionAmount: body.contributionAmount,
          subscriptionStartDate: new Date()
        },
        { new: false, projection: { status: 1 } }
      )
      const isFirstActivation = preMember?.status === 'pending_payment'
      const member = await Member.findById(preMember._id)

      logActivity(member._id, 'subscription_created', { amount: body.contributionAmount })

      await inviteToSlack(member)
      if (isFirstActivation) await sendWelcomeEmail(member)

      return {
        success: true,
        subscription: null,
        member: {
          id: member._id,
          email: member.email,
          name: member.name,
          circle: member.circle,
          contributionAmount: member.contributionAmount,
          status: member.status
        }
      }
    }

    // Validate card token is provided
    if (!body.cardToken) {
      throw createError({
        statusCode: 400,
        statusMessage: 'Payment information is required for a paid contribution'
      })
    }

    const cadence = body.cadence
    const paymentPlanId = getHelcimPlanId(cadence)
    const recurringAmount = cadence === 'annual'
      ? body.contributionAmount * 12
      : body.contributionAmount

    if (!paymentPlanId) {
      throw createError({
        statusCode: 500,
        statusMessage: cadence === 'annual'
          ? 'Annual plan id not configured'
          : 'Monthly plan id not configured',
      })
    }

    const idempotencyKey = generateIdempotencyKey()

    const subscriptionPayload = {
      dateActivated: new Date().toISOString().split('T')[0],
      paymentPlanId: parseInt(paymentPlanId),
      customerCode: body.customerCode,
      recurringAmount,
      paymentMethod: 'card',
    }

    const subscriptionData = await createHelcimSubscription(subscriptionPayload, idempotencyKey)

    // Extract the first subscription from the response array
    const subscription = subscriptionData.data?.[0]
    if (!subscription) {
      throw createError({ statusCode: 500, statusMessage: 'Subscription creation failed' })
    }

    const nextBillingDate = subscription.nextBillingDate
      ? new Date(subscription.nextBillingDate)
      : null

    // Atomically capture pre-update status alongside the write so we can
    // detect the pending_payment → active transition without a separate read
    // (which would race with concurrent webhooks/double-clicks).
    const preMember = await Member.findOneAndUpdate(
      { helcimCustomerId: body.customerId },
      { $set: {
          contributionAmount: body.contributionAmount,
          helcimSubscriptionId: subscription.id,
          helcimCustomerId: body.customerId,
          paymentMethod: 'card',
          billingCadence: cadence,
          subscriptionStartDate: new Date(),
          status: 'active',
          ...(nextBillingDate && !Number.isNaN(nextBillingDate.getTime())
            ? { nextBillingDate }
            : {}),
        } },
      { new: false, runValidators: false, projection: { status: 1 } }
    )
    const isFirstActivation = preMember?.status === 'pending_payment'
    const member = await Member.findById(preMember._id)

    logActivity(member._id, 'subscription_created', { amount: body.contributionAmount })

    try {
      const txs = await listHelcimCustomerTransactions(body.customerCode)
      const latestPaid = txs.find((t) => t.status === 'paid')
      if (latestPaid) {
        await upsertPaymentFromHelcim(member, latestPaid, {
          paymentType: cadence,
          sendConfirmation: true
        })
      }
    } catch (err) {
      console.error('[payments] initial charge log failed, will be picked up by reconciliation:', err?.message || err)
    }

    await inviteToSlack(member)
    if (isFirstActivation) await sendWelcomeEmail(member)

    return {
      success: true,
      subscription: {
        subscriptionId: subscription.id,
        status: subscription.status,
        nextBillingDate: subscription.nextBillingDate
      },
      member: {
        id: member._id,
        email: member.email,
        name: member.name,
        circle: member.circle,
        contributionAmount: member.contributionAmount,
        status: member.status
      }
    }
  } catch (error) {
    if (error.statusCode) throw error
    console.error('Error creating Helcim subscription:', error)
    throw createError({
      statusCode: 500,
      statusMessage: 'An unexpected error occurred'
    })
  }
})