import { getRuntimeEnv } from "../../../lib/runtime-env";
import {
  exchangeWecomOAuthCode,
  fetchWecomExternalContactName,
  resolveWecomConfig,
  WecomClientError,
  type WecomBindings,
} from "../../../lib/wecom-client";
import { signWecomIdentityTicket } from "../../../lib/wecom-oauth-service";
import { partnerOptions, withPartnerCors } from "../../../lib/partner-cors";

const env = getRuntimeEnv();

export function OPTIONS(request: Request) {
  return partnerOptions(request);
}

async function handlePost(request: Request) {
  try {
    const body = (await request.json().catch(() => ({}))) as { code?: string };
    const code = String(body.code ?? "").trim();
    const config = resolveWecomConfig(env as unknown as WecomBindings);
    if (!config.corpId || !config.agentId || !config.secret) {
      return Response.json(
        { error: "未配置企业微信授权（WECOM_CORP_ID / WECOM_AGENT_ID / WECOM_SECRET）" },
        { status: 501 },
      );
    }
    if (!code) {
      return Response.json({ error: "缺少授权 code" }, { status: 400 });
    }
    const identity = await exchangeWecomOAuthCode(config, code);
    if (identity.externalUserId) {
      const displayName =
        (await fetchWecomExternalContactName(config, identity.externalUserId)) ??
        "企微客户";
      const { ticket, expiresIn } = await signWecomIdentityTicket(
        identity.externalUserId,
        displayName,
      );
      return Response.json({
        userType: "external",
        identityTicket: ticket,
        displayName,
        expiresIn,
      });
    }
    return Response.json({
      userType: "internal",
      userId: identity.userId ?? "",
    });
  } catch (error) {
    const status = error instanceof WecomClientError ? error.status : 500;
    return Response.json(
      { error: error instanceof Error ? error.message : "授权失败" },
      { status },
    );
  }
}

export async function POST(request: Request) {
  const response = await handlePost(request);
  response.headers.set("Cache-Control", "private, no-store");
  return withPartnerCors(request, response);
}