import { NextResponse } from "next/server";
import { randomUUID } from "node:crypto";
import { getPayload } from "payload";
import config from "@payload-config";
import { getClientIp, checkRateLimit } from "@/lib/auth/rateLimit";
import { newConversationAdminEmail } from "@/lib/email/conversationTemplates";
import { sendEmail } from "@/lib/email/sendBookingEmails";
import { verifyTurnstileToken } from "@/lib/turnstile/server";

export const dynamic = "force-dynamic";

type Body = {
  name?: unknown;
  email?: unknown;
  message?: unknown;
  subject?: unknown;
  type?: unknown;
  token?: unknown;
};

function clean(value: unknown, max: number): string {
  return typeof value === "string" ? value.trim().slice(0, max) : "";
}

export async function POST(request: Request) {
  let body: Body;
  try {
    body = await request.json();
  } catch {
    return NextResponse.json({ error: "Ungültige Anfrage." }, { status: 400 });
  }

  const name = clean(body.name, 160);
  const email = clean(body.email, 254).toLowerCase();
  const message = clean(body.message, 5000);
  const subject = clean(body.subject, 180) || "Allgemeine Anfrage";
  const type = body.type === "appointment" ? "appointment" : "contact";

  if (!name || !email || !message || !/^\S+@\S+\.\S+$/.test(email)) {
    return NextResponse.json({ error: "Bitte fülle alle Pflichtfelder korrekt aus." }, { status: 400 });
  }
  if (!(await verifyTurnstileToken(body.token, "contact", request))) {
    return NextResponse.json({ error: "Sicherheitsprüfung fehlgeschlagen. Bitte versuche es erneut." }, { status: 403 });
  }
  if (!checkRateLimit(`contact:ip:${getClientIp(request)}`, { max: 8, windowMs: 60 * 60 * 1000 })) {
    return NextResponse.json({ error: "Zu viele Anfragen. Bitte versuche es später erneut." }, { status: 429 });
  }

  try {
    const payload = await getPayload({ config });
    const { user } = await payload.auth({ headers: request.headers });
    const customerId = user?.collection === "customers" ? user.id : undefined;
    const conversation = await payload.create({
      collection: "conversations",
      overrideAccess: true,
      data: {
        name,
        email,
        subject,
        type,
        status: "open",
        threadKey: randomUUID(),
        ...(customerId ? { customer: customerId } : {}),
        lastMessageAt: new Date().toISOString(),
      },
    });
    await payload.create({
      collection: "conversation-messages",
      overrideAccess: true,
      data: {
        conversation: conversation.id,
        senderType: "visitor",
        senderName: name,
        senderEmail: email,
        body: message,
      },
    });

    const contact = await payload.findGlobal({ slug: "contact", overrideAccess: true });
    const serverUrl = process.env.NEXT_PUBLIC_SERVER_URL || new URL(request.url).origin;
    const adminUrl = `${serverUrl}/admin/collections/conversations/${conversation.id}`;
    if (contact.email) {
      await sendEmail(contact.email, newConversationAdminEmail({ name, email, subject, body: message, adminUrl, threadKey: conversation.threadKey }), {
        replyTo: process.env.INBOUND_REPLY_TO || "reply-to@anouma.org",
      });
    }
    return NextResponse.json({ ok: true });
  } catch (error) {
    console.error("contact inquiry failed", error);
    return NextResponse.json({ error: "Die Nachricht konnte nicht gesendet werden. Bitte versuche es später erneut." }, { status: 500 });
  }
}