import { NextRequest, NextResponse } from "next/server"
import prisma from "@/lib/prisma"
import { createPledgeSchema } from "@/lib/validators"
import { generateReference } from "@/lib/reference"
import { calculateReminderSchedule } from "@/lib/reminders"
import { sendPledgeReceipt } from "@/lib/whatsapp"

export async function POST(request: NextRequest) {
  try {
    const body = await request.json()

    if (!prisma) {
      return NextResponse.json({ error: "Database not configured" }, { status: 503 })
    }

    const parsed = createPledgeSchema.safeParse(body)
    if (!parsed.success) {
      return NextResponse.json(
        { error: "Invalid data", details: parsed.error.flatten() },
        { status: 400 }
      )
    }

    const { amountPence, rail, donorName, donorEmail, donorPhone, giftAid, eventId, qrSourceId } = parsed.data

    // Get event + org
    const event = await prisma.event.findUnique({
      where: { id: eventId },
      include: { organization: true },
    })

    if (!event) {
      return NextResponse.json({ error: "Event not found" }, { status: 404 })
    }

    const org = event.organization

    // Generate unique reference (retry on collision)
    let reference = ""
    let attempts = 0
    while (attempts < 10) {
      reference = generateReference(org.refPrefix || "PNPL", amountPence)
      const exists = await prisma.pledge.findUnique({ where: { reference } })
      if (!exists) break
      attempts++
    }
    if (attempts >= 10) {
      return NextResponse.json({ error: "Could not generate unique reference" }, { status: 500 })
    }

    // Create pledge + payment instruction + reminder schedule in transaction
    // eslint-disable-next-line @typescript-eslint/no-explicit-any
    const pledge = await prisma.$transaction(async (tx: any) => {
      const p = await tx.pledge.create({
        data: {
          reference,
          amountPence,
          currency: "GBP",
          rail,
          status: "new",
          donorName: donorName || null,
          donorEmail: donorEmail || null,
          donorPhone: donorPhone || null,
          giftAid,
          eventId,
          qrSourceId: qrSourceId || null,
          organizationId: org.id,
        },
      })

      // Create payment instruction for bank transfers
      if (rail === "bank" && org.bankSortCode && org.bankAccountNo) {
        await tx.paymentInstruction.create({
          data: {
            pledgeId: p.id,
            bankReference: reference,
            bankDetails: {
              bankName: org.bankName || "",
              sortCode: org.bankSortCode,
              accountNo: org.bankAccountNo,
              accountName: org.bankAccountName || org.name,
            },
          },
        })
      }

      // Create reminder schedule
      const schedule = calculateReminderSchedule(new Date())
      await tx.reminder.createMany({
        data: schedule.map((s) => ({
          pledgeId: p.id,
          step: s.step,
          channel: s.channel,
          scheduledAt: s.scheduledAt,
          status: "pending",
          payload: { templateKey: s.templateKey, subject: s.subject },
        })),
      })

      // Track analytics
      await tx.analyticsEvent.create({
        data: {
          eventType: "pledge_completed",
          pledgeId: p.id,
          eventId,
          qrSourceId: qrSourceId || null,
          metadata: { amountPence, rail },
        },
      })

      return p
    })

    // Build response
    const response: Record<string, unknown> = {
      id: pledge.id,
      reference: pledge.reference,
    }

    if (rail === "bank" && org.bankSortCode) {
      response.bankDetails = {
        bankName: org.bankName || "",
        sortCode: org.bankSortCode,
        accountNo: org.bankAccountNo || "",
        accountName: org.bankAccountName || org.name,
      }
    }

    // Async: Send WhatsApp receipt to donor (non-blocking)
    if (donorPhone) {
      sendPledgeReceipt(donorPhone, {
        donorName: donorName || undefined,
        amountPounds: (amountPence / 100).toFixed(0),
        eventName: event.name,
        reference: pledge.reference,
        rail,
        bankDetails: rail === "bank" && org.bankSortCode ? {
          sortCode: org.bankSortCode,
          accountNo: org.bankAccountNo || "",
          accountName: org.bankAccountName || org.name,
        } : undefined,
        orgName: org.name,
      }).catch(err => console.error("[WAHA] Receipt send failed:", err))
    }

    // Async: Notify volunteer if QR source has volunteer info
    if (qrSourceId) {
      prisma?.qrSource.findUnique({
        where: { id: qrSourceId },
        select: { volunteerName: true, label: true, pledges: { select: { amountPence: true } } },
      }).then(qr => {
        // In future: if volunteer has a phone number stored, send WhatsApp notification
        // For now, this is a no-op unless volunteer phone is added to schema
        if (qr) {
          console.log(`[PLEDGE] ${qr.volunteerName || qr.label}: +1 pledge (£${(amountPence / 100).toFixed(0)})`)
        }
      }).catch(() => {})
    }

    return NextResponse.json(response, { status: 201 })
  } catch (error) {
    console.error("Pledge creation error:", error)
    return NextResponse.json({ error: "Internal error" }, { status: 500 })
  }
}