import { NextResponse } from 'next/server';
import { auth } from '@/lib/auth/config';
import { prisma } from '@/lib/db/prisma';
import { createReservationSchema } from '@/lib/validations/reservation';
import { sendEmail, buildReservationConfirmationHtml } from '@/lib/email';

export async function POST(request: Request) {
  const session = await auth();
  if (!session?.user?.id) {
    return NextResponse.json({ error: 'Autenticação necessária.' }, { status: 401 });
  }

  const body = await request.json();
  const parsed = createReservationSchema.safeParse(body);

  if (!parsed.success) {
    return NextResponse.json(
      { error: 'Dados inválidos.', details: parsed.error.flatten() },
      { status: 400 }
    );
  }

  const { animalId, date, notes } = parsed.data;

  // Verificar que o animal existe e está disponível
  const animal = await prisma.animal.findUnique({
    where: { id: animalId },
    include: { shelter: { select: { name: true } } },
  });

  if (!animal) {
    return NextResponse.json({ error: 'Animal não encontrado.' }, { status: 404 });
  }
  if (animal.status !== 'AVAILABLE') {
    return NextResponse.json({ error: 'Animal não disponível para reserva.' }, { status: 409 });
  }

  // Criar reserva + marcar animal como RESERVED em transacção
  const reservation = await prisma.$transaction(async (tx) => {
    const res = await tx.reservation.create({
      data: {
        userId:   session.user!.id!,
        animalId,
        date:     new Date(date),
        status:   'PENDING',
        notes,
      },
      include: {
        user:   { select: { name: true, email: true } },
        animal: { select: { name: true, shelter: { select: { name: true } } } },
      },
    });

    await tx.animal.update({
      where: { id: animalId },
      data:  { status: 'RESERVED' },
    });

    return res;
  });

  // Enviar email de confirmação (não bloqueia a resposta)
  sendEmail({
    to:      reservation.user.email,
    subject: `Reserva confirmada — ${reservation.animal.name} 🐾`,
    html:    buildReservationConfirmationHtml({
      userName:    reservation.user.name,
      animalName:  reservation.animal.name,
      shelterName: reservation.animal.shelter.name,
      date:        new Date(date).toLocaleDateString('pt-PT', {
        weekday: 'long', year: 'numeric', month: 'long', day: 'numeric',
      }),
    }),
  }).catch(console.error);

  return NextResponse.json(reservation, { status: 201 });
}

export async function GET(request: Request) {
  const session = await auth();
  if (!session?.user?.id) {
    return NextResponse.json({ error: 'Autenticação necessária.' }, { status: 401 });
  }

  const reservations = await prisma.reservation.findMany({
    where:   { userId: session.user.id },
    include: {
      animal: {
        include: {
          photos:  { where: { isPrimary: true }, take: 1 },
          shelter: { select: { name: true, district: true } },
        },
      },
    },
    orderBy: { date: 'desc' },
  });

  return NextResponse.json(reservations);
}