import { NextResponse } from 'next/server';
import { Resend } from 'resend';

export const runtime = 'edge';

type ContactPayload = {
  name?: string;
  company?: string;
  service?: string;
  budget?: string;
  message?: string;
  locale?: 'fa' | 'en';
};

const required = ['name', 'service', 'budget', 'message'] as const;

function escape(str: string) {
  return str
    .replace(/&/g, '&')
    .replace(/</g, '&lt;')
    .replace(/>/g, '&gt;')
    .replace(/"/g, '&quot;');
}

export async function POST(req: Request) {
  let body: ContactPayload;
  try {
    body = (await req.json()) as ContactPayload;
  } catch {
    return NextResponse.json({ error: 'Invalid JSON' }, { status: 400 });
  }

  for (const k of required) {
    if (!body[k] || String(body[k]).trim().length < 2) {
      return NextResponse.json(
        { error: `Missing field: ${k}` },
        { status: 422 },
      );
    }
  }

  const apiKey = process.env.RESEND_API_KEY;
  const inbox = process.env.CONTACT_INBOX;
  const from = process.env.CONTACT_FROM;

  // Graceful no-op for local dev so the form UX can be validated
  // without forcing a Resend key. Production should set these.
  if (!apiKey || !inbox || !from) {
    if (process.env.NODE_ENV === 'production') {
      return NextResponse.json(
        { error: 'Email service is not configured' },
        { status: 500 },
      );
    }
    console.info('[contact] received (no Resend key — logging only):', body);
    return NextResponse.json({ ok: true, dev: true });
  }

  const resend = new Resend(apiKey);
  const subject = `New consultation request — ${body.name}`;
  const html = `
    <div style="font-family: ui-sans-serif, system-ui, sans-serif; line-height: 1.55;">
      <h2 style="margin: 0 0 12px;">New consultation request</h2>
      <table style="border-collapse: collapse;">
        <tr><td style="padding: 4px 12px 4px 0; color:#475569;">Name</td><td>${escape(body.name!)}</td></tr>
        <tr><td style="padding: 4px 12px 4px 0; color:#475569;">Company</td><td>${escape(body.company ?? '')}</td></tr>
        <tr><td style="padding: 4px 12px 4px 0; color:#475569;">Service</td><td>${escape(body.service!)}</td></tr>
        <tr><td style="padding: 4px 12px 4px 0; color:#475569;">Budget</td><td>${escape(body.budget!)}</td></tr>
        <tr><td style="padding: 4px 12px 4px 0; color:#475569;">Locale</td><td>${escape(body.locale ?? '')}</td></tr>
      </table>
      <h3 style="margin: 20px 0 6px;">Message</h3>
      <p style="white-space: pre-wrap; background:#f8fafc; padding:12px; border-radius:8px;">${escape(body.message!)}</p>
    </div>
  `;

  try {
    const { error } = await resend.emails.send({
      from,
      to: inbox,
      subject,
      html,
      replyTo: body.company ? `${body.name} <${body.company}>` : undefined,
    });
    if (error) {
      console.error('[contact] resend error', error);
      return NextResponse.json(
        { error: 'Email service rejected the request' },
        { status: 502 },
      );
    }
    return NextResponse.json({ ok: true });
  } catch (err) {
    console.error('[contact] send failed', err);
    return NextResponse.json(
      { error: 'Email service unreachable' },
      { status: 502 },
    );
  }
}