import { NextResponse } from 'next/server';
import { prisma } from '@/lib/db/prisma';
import { registerSchema } from '@/lib/validations/auth';
import { hashPassword } from '@/lib/auth/password';
import { validateAge } from '@/lib/auth/age-validation';
import { sendEmail, buildWelcomeHtml } from '@/lib/email';

export async function POST(request: Request) {
  const body = await request.json();
  const parsed = registerSchema.safeParse(body);

  if (!parsed.success) {
    const errors = parsed.error.flatten().fieldErrors;
    const firstError = Object.values(errors).flat()[0];
    return NextResponse.json({ error: firstError ?? 'Dados inválidos.' }, { status: 400 });
  }

  const { name, email, password, birthdate, district } = parsed.data;

  // Validação de +18 sempre no servidor
  const ageCheck = validateAge(birthdate);
  if (!ageCheck.valid) {
    return NextResponse.json({ error: ageCheck.error }, { status: 400 });
  }

  // Verificar se email já existe
  const existing = await prisma.user.findUnique({ where: { email } });
  if (existing) {
    return NextResponse.json({ error: 'Este email já está registado.' }, { status: 409 });
  }

  const hashedPassword = await hashPassword(password);

  const user = await prisma.user.create({
    data: {
      name,
      email,
      password:  hashedPassword,
      birthdate: new Date(birthdate),
      district,
    },
    select: { id: true, name: true, email: true },
  });

  // Email de boas-vindas (não bloqueia)
  sendEmail({
    to:      user.email,
    subject: 'Bem-vindo à PetLink 🐾',
    html:    buildWelcomeHtml({ userName: user.name }),
  }).catch(console.error);

  return NextResponse.json(
    { message: 'Conta criada com sucesso.', userId: user.id },
    { status: 201 }
  );
}