import { NextRequest, NextResponse } from "next/server";
import { getPocketBaseConfig, SITE_ID } from "@/config/services.config";

async function getAdminToken(): Promise<string | null> {
  const email = process.env.POCKETBASE_EMAIL;
  const password = process.env.POCKETBASE_PASSWORD;
  if (!email || !password) return null;
  const pb = getPocketBaseConfig();
  const res = await fetch(`${pb.url}/api/admins/auth-with-password`, {
    method: "POST",
    headers: { "Content-Type": "application/json" },
    body: JSON.stringify({ identity: email, password }),
  });
  if (!res.ok) return null;
  const data = await res.json();
  return data?.token ?? null;
}

/** 将匿名 user_id 的支付记录关联到新创建的 PB 用户 */
async function linkPaymentsToUser(
  adminToken: string,
  fromUserId: string,
  toUserId: string
): Promise<void> {
  const pb = getPocketBaseConfig();
  const filter = `user_id = "${fromUserId}"`;
  const res = await fetch(
    `${pb.url}/api/collections/payments/records?filter=${encodeURIComponent(filter)}&perPage=500`,
    { headers: { Authorization: `Bearer ${adminToken}` } }
  );
  if (!res.ok) return;
  const data = await res.json();
  const items = data?.items ?? [];
  for (const item of items) {
    await fetch(`${pb.url}/api/collections/payments/records/${item.id}`, {
      method: "PATCH",
      headers: {
        "Content-Type": "application/json",
        Authorization: `Bearer ${adminToken}`,
      },
      body: JSON.stringify({ user_id: toUserId }),
    });
  }
}

async function linkSiteVipToUser(
  adminToken: string,
  fromUserId: string,
  toUserId: string
): Promise<void> {
  const pb = getPocketBaseConfig();
  const filter = `user_id = "${fromUserId}" && site_id = "${SITE_ID}"`;
  const res = await fetch(
    `${pb.url}/api/collections/site_vip/records?filter=${encodeURIComponent(filter)}&perPage=500`,
    { headers: { Authorization: `Bearer ${adminToken}` } }
  );
  if (!res.ok) return;
  const data = await res.json();
  const items = data?.items ?? [];
  for (const item of items) {
    await fetch(`${pb.url}/api/collections/site_vip/records/${item.id}`, {
      method: "PATCH",
      headers: {
        "Content-Type": "application/json",
        Authorization: `Bearer ${adminToken}`,
      },
      body: JSON.stringify({ user_id: toUserId }),
    });
  }
}

export async function POST(request: NextRequest) {
  const body = await request.json().catch(() => ({}));
  const email = String(body?.email ?? "").trim();
  const password = String(body?.password ?? "").trim();
  const anonymousUserId = String(body?.anonymousUserId ?? "").trim();

  if (!email || !password) {
    return NextResponse.json({ ok: false, error: "请填写邮箱和密码" }, { status: 400 });
  }
  if (!anonymousUserId || !anonymousUserId.startsWith("user")) {
    return NextResponse.json({ ok: false, error: "无效的匿名用户ID" }, { status: 400 });
  }
  if (password.length < 8) {
    return NextResponse.json({ ok: false, error: "密码至少 8 位" }, { status: 400 });
  }

  const pb = getPocketBaseConfig();

  // 1. 尝试注册，若已存在则登录
  let token: string;
  let record: { id: string; email?: string };
  try {
    const registerRes = await fetch(`${pb.url}/api/collections/users/records`, {
      method: "POST",
      headers: { "Content-Type": "application/json" },
      body: JSON.stringify({ email, password, passwordConfirm: password }),
    });
    if (registerRes.ok) {
      const regData = await registerRes.json();
      const loginRes = await fetch(`${pb.url}/api/collections/users/auth-with-password`, {
        method: "POST",
        headers: { "Content-Type": "application/json" },
        body: JSON.stringify({ identity: email, password }),
      });
      if (!loginRes.ok) throw new Error("登录失败");
      const loginData = await loginRes.json();
      token = loginData.token;
      record = loginData.record;
    } else {
      const loginRes = await fetch(`${pb.url}/api/collections/users/auth-with-password`, {
        method: "POST",
        headers: { "Content-Type": "application/json" },
        body: JSON.stringify({ identity: email, password }),
      });
      if (!loginRes.ok) {
        const err = await loginRes.json().catch(() => ({}));
        return NextResponse.json(
          { ok: false, error: err?.message || "邮箱或密码错误" },
          { status: 401 }
        );
      }
      const loginData = await loginRes.json();
      token = loginData.token;
      record = loginData.record;
    }
  } catch (e) {
    return NextResponse.json(
      { ok: false, error: e instanceof Error ? e.message : "注册/登录失败" },
      { status: 500 }
    );
  }

  const newUserId = record.id;

  // 2. 用管理员 token 将 payments、site_vip 的 user_id 从匿名改为新用户
  const adminToken = await getAdminToken();
  if (adminToken) {
    await linkPaymentsToUser(adminToken, anonymousUserId, newUserId);
    await linkSiteVipToUser(adminToken, anonymousUserId, newUserId);
  }

  return NextResponse.json({
    ok: true,
    token,
    record: { id: record.id, email: record.email },
  });
}