import { NextResponse } from "next/server"
import { and, eq, lt } from "drizzle-orm"
import { db } from "@/lib/db"
import { rent_payments } from "@/lib/db/schema"
import { sendEmail, rentDueReminderHtml, rentOverdueHtml } from "@/lib/email/send"
import { formatCurrency, formatDate } from "@/lib/utils"
import { isAuthorizedCron } from "@/lib/cron-auth"

// Called by Vercel Cron — runs daily
export async function GET(request: Request) {
  if (!isAuthorizedCron(request)) {
    return NextResponse.json({ error: "Unauthorized" }, { status: 401 })
  }

  const today = new Date().toISOString().slice(0, 10)
  const in3Days = new Date()
  in3Days.setDate(in3Days.getDate() + 3)
  const in3DaysStr = in3Days.toISOString().slice(0, 10)

  // Payments due in 3 days → send reminder
  const upcoming = await db.query.rent_payments.findMany({
    where: and(eq(rent_payments.status, "pending"), eq(rent_payments.due_date, in3DaysStr)),
    with: {
      tenant: { columns: { first_name: true, last_name: true, email: true } },
      property: { columns: { name: true } },
      unit: { columns: { unit_number: true } },
    },
  })

  for (const payment of upcoming) {
    if (!payment.tenant?.email) continue
    await sendEmail({
      to: payment.tenant.email,
      subject: `Rent Due in 3 Days — ${payment.property?.name}`,
      html: rentDueReminderHtml({
        tenantName: `${payment.tenant.first_name} ${payment.tenant.last_name}`,
        propertyName: payment.property?.name ?? "",
        unitNumber: payment.unit?.unit_number ?? "—",
        amount: formatCurrency(payment.amount),
        dueDate: formatDate(payment.due_date),
      }),
    })
  }

  // Payments past due date → mark overdue + send notice
  const pastDue = await db.query.rent_payments.findMany({
    where: and(eq(rent_payments.status, "pending"), lt(rent_payments.due_date, today)),
    with: {
      tenant: { columns: { first_name: true, last_name: true, email: true } },
      property: { columns: { name: true } },
      unit: { columns: { unit_number: true } },
    },
  })

  for (const payment of pastDue) {
    await db
      .update(rent_payments)
      .set({ status: "overdue" })
      .where(eq(rent_payments.id, payment.id))

    if (!payment.tenant?.email) continue
    await sendEmail({
      to: payment.tenant.email,
      subject: `Rent Overdue — ${payment.property?.name}`,
      html: rentOverdueHtml({
        tenantName: `${payment.tenant.first_name} ${payment.tenant.last_name}`,
        propertyName: payment.property?.name ?? "",
        unitNumber: payment.unit?.unit_number ?? "—",
        amount: formatCurrency(payment.amount),
        dueDate: formatDate(payment.due_date),
      }),
    })
  }

  return NextResponse.json({
    reminders_sent: upcoming.length,
    marked_overdue: pastDue.length,
  })
}