import { randomBytes } from "node:crypto";
import { qqDnaEmailPool } from "@/lib/flock/qqdna-email-pool";

const PLUS_ALIAS_DOMAINS = new Set([
  "gmail.com",
  "googlemail.com",
  "outlook.com",
  "hotmail.com",
  "live.com",
  "yahoo.com",
  "icloud.com",
  "me.com",
]);

/** 录制验证可用的 QQ（随机虚构 QQ 会被官网拒绝） */
const VERIFIED_QQ_BASE = "3457189488@qq.com";

/** 轮询取池，避免同次批量撞同一邮箱 */
let poolCursor = 0;

function takeFromPool(pool: string[]): string {
  if (pool.length === 0) {
    throw new Error("empty email pool");
  }
  const item = pool[poolCursor % pool.length]!;
  poolCursor += 1;
  return item;
}

/** 解析逗号/分号/换行分隔的池 */
export function parseFlockEnvPool(raw: string | undefined): string[] {
  if (!raw?.trim()) {
    return [];
  }
  return raw
    .split(/[,;\n]+/)
    .map((s) => s.trim())
    .filter(Boolean);
}

function pickPoolItem(pool: string[]): string {
  return takeFromPool(pool);
}

function randomUsPhone10(): string {
  const areaCodes = [
    212, 213, 310, 312, 404, 408, 415, 469, 512, 617, 626, 702, 713, 718, 753,
    786, 818, 832, 917, 972,
  ];
  const area = areaCodes[randomBytes(1)[0]! % areaCodes.length]!;
  // 避开 N11 保留号段（411 等），否则官网可能禁用提交
  let exchange = 200 + (randomBytes(1)[0]! % 800);
  if (exchange % 100 === 11) {
    exchange += 1;
  }
  const line = String(1000 + (randomBytes(2).readUInt16BE(0) % 9000));
  return `${area}${exchange}${line}`.slice(0, 10);
}

/**
 * 短 QQ 邮箱：1/2/3 开头 + 9 位随机数字
 * 注意：虚构 QQ 号常被 Flock 以「We had an issue creating your account」拒绝
 * 仅 FLOCK_EMAIL_MODE=random_qq 时使用
 */
export function createRandomQqEmail(): string {
  const prefix = 1 + (randomBytes(1)[0]! % 3);
  const nineDigits = String(randomBytes(4).readUInt32BE(0) % 1_000_000_000).padStart(
    9,
    "0",
  );
  return `${prefix}${nineDigits}@qq.com`;
}

/**
 * 已验证 QQ + 短别名：3457189488+a1b2c3@qq.com（总计较短）
 * 官网曾对该格式成功出过价
 */
export function createVerifiedQqAliasedEmail(): string {
  const tag = randomBytes(3).toString("hex"); // 6 字符
  return `3457189488+${tag}@qq.com`;
}

/** Gmail/Outlook 等 + 子地址 */
export function buildFlockAliasedEmail(baseEmail: string, unique: string): string {
  const trimmed = baseEmail.trim();
  const at = trimmed.lastIndexOf("@");
  if (at < 1) {
    return trimmed;
  }
  const local = trimmed.slice(0, at).split("+")[0]!;
  const domain = trimmed.slice(at + 1).toLowerCase();
  const tag =
    unique.replace(/[^a-z0-9]/gi, "").slice(0, 8) ||
    randomBytes(3).toString("hex");

  if (PLUS_ALIAS_DOMAINS.has(domain)) {
    return `${local}+${tag}@${domain}`;
  }
  if (domain === "qq.com") {
    return `${local}+${tag.slice(0, 6)}@qq.com`;
  }
  return createVerifiedQqAliasedEmail();
}

function resolveFreshEmail(id: string, ts: string): string {
  const emailPool = parseFlockEnvPool(process.env.FLOCK_EMAIL_POOL);
  if (emailPool.length > 0) {
    return pickPoolItem(emailPool);
  }

  const mode = process.env.FLOCK_EMAIL_MODE?.trim().toLowerCase();
  // qq.qqdna.com 号码库拼 @qq.com（用户指定探针模式）
  if (mode === "qqdna" || mode === "qq_dna") {
    return takeFromPool(qqDnaEmailPool());
  }
  if (mode === "random_qq") {
    return createRandomQqEmail();
  }

  const aliasBase =
    process.env.FLOCK_EMAIL_ALIAS_BASE?.trim() ||
    process.env.FLOCK_TEST_EMAIL?.trim() ||
    VERIFIED_QQ_BASE;

  const domain = aliasBase.split("@")[1]?.toLowerCase() ?? "";
  if (PLUS_ALIAS_DOMAINS.has(domain) || domain === "qq.com") {
    return buildFlockAliasedEmail(aliasBase, `${ts}${id}`);
  }

  return createVerifiedQqAliasedEmail();
}

const FIRST_NAMES = [
  "James",
  "Michael",
  "Robert",
  "David",
  "Daniel",
  "Emily",
  "Sarah",
  "Jessica",
  "Amanda",
  "Lauren",
] as const;

const LAST_NAMES = [
  "Johnson",
  "Williams",
  "Brown",
  "Miller",
  "Davis",
  "Wilson",
  "Anderson",
  "Taylor",
  "Thomas",
  "Moore",
] as const;

const COMPANIES = [
  "Pacific Freight Solutions",
  "Horizon Logistics LLC",
  "Summit Cargo Partners",
  "Northstar Shipping Co",
  "Blue Ridge Transport",
  "Atlas Trucking Group",
  "Crescent Supply Chain",
  "Midwest Load Line",
] as const;

function pickName(list: readonly string[]): string {
  return list[randomBytes(1)[0]! % list.length]!;
}

/**
 * 每次查价生成新注册账号：
 * - 优先 FLOCK_EMAIL_POOL
 * - FLOCK_EMAIL_MODE=qqdna：qq.qqdna.com 号码 + @qq.com
 * - FLOCK_EMAIL_MODE=random_qq：虚构 {1|2|3}{9位}@qq.com
 * - 默认：已验证 QQ + 短 +别名
 * 姓名/公司用真人风格（避免 Guest3493 触发风控）
 */
export function createFreshFlockTestAccount(): {
  firstName: string;
  lastName: string;
  company: string;
  phone: string;
  email: string;
  shipmentsPerMonth: string;
} {
  const id = randomBytes(5).toString("hex");
  const ts = Date.now().toString(36);

  const phonePool = parseFlockEnvPool(process.env.FLOCK_PHONE_POOL).map((p) =>
    p.replace(/\D/g, "").slice(-10),
  );

  const email = resolveFreshEmail(id, ts);
  const phone =
    phonePool.length > 0 ? pickPoolItem(phonePool) : randomUsPhone10();

  return {
    firstName: process.env.FLOCK_TEST_FIRST_NAME?.trim() || pickName(FIRST_NAMES),
    lastName: process.env.FLOCK_TEST_LAST_NAME?.trim() || pickName(LAST_NAMES),
    company: process.env.FLOCK_TEST_COMPANY?.trim() || pickName(COMPANIES),
    phone,
    email,
    shipmentsPerMonth:
      process.env.FLOCK_TEST_SHIPMENTS_MONTH?.trim() || "1-25",
  };
}