import { readBody } from "h3";
import { prisma } from "../../../../../utils/prisma";
import { verifyLinkToken } from "../../../../../utils/telegramBusinessConnect";

type CompleteBody = {
  token?: string;
};

export default defineEventHandler(async (event) => {
  const body = await readBody<CompleteBody>(event);
  const token = String(body?.token ?? "").trim();
  if (!token) {
    throw createError({ statusCode: 400, statusMessage: "token is required" });
  }

  const payload = verifyLinkToken(token);
  if (!payload) {
    return { ok: false, status: "invalid_or_expired_token" };
  }

  const pendingId = `pending:${payload.nonce}`;
  const pending = await prisma.telegramBusinessConnection.findFirst({
    where: {
      teamId: payload.teamId,
      businessConnectionId: pendingId,
    },
  });

  if (!pending) {
    return { ok: false, status: "session_not_found" };
  }

  const raw = (pending.rawJson ?? {}) as any;
  const telegramUserId = raw?.link?.telegramUserId != null ? String(raw.link.telegramUserId).trim() : "";
  if (!telegramUserId) {
    return { ok: false, status: "awaiting_telegram_start" };
  }

  const linkedConnectionId = `link:${telegramUserId}`;
  await prisma.$transaction([
    prisma.telegramBusinessConnection.upsert({
      where: {
        teamId_businessConnectionId: {
          teamId: payload.teamId,
          businessConnectionId: linkedConnectionId,
        },
      },
      create: {
        teamId: payload.teamId,
        businessConnectionId: linkedConnectionId,
        isEnabled: true,
        canReply: true,
        rawJson: {
          state: "connected",
          mode: "token_link",
          linkedAt: new Date().toISOString(),
          telegramUserId,
          tokenNonce: payload.nonce,
        },
      },
      update: {
        isEnabled: true,
        canReply: true,
        rawJson: {
          state: "connected",
          mode: "token_link",
          linkedAt: new Date().toISOString(),
          telegramUserId,
          tokenNonce: payload.nonce,
        },
      },
    }),
    prisma.telegramBusinessConnection.delete({ where: { id: pending.id } }),
  ]);

  return {
    ok: true,
    status: "connected",
    businessConnectionId: linkedConnectionId,
  };
});