import {
  PrismaClient,
  AdType,
  ImageSource,
  Prisma,
} from '@prisma/mongo/client';

const prisma = new PrismaClient();

type SeedArgs = {
  clean: boolean;
  perType: number;
};

function parseArgs(argv: string[]): SeedArgs {
  const clean =
    argv.includes('--clean') ||
    argv.includes('-c') ||
    process.env.SEED_CLEAN === '1' ||
    process.env.SEED_CLEAN === 'true';

  const perTypeFromArg = (() => {
    const idx = argv.findIndex((a) => a === '--perType');
    if (idx >= 0) {
      const v = Number(argv[idx + 1]);
      if (Number.isFinite(v) && v > 0) return Math.floor(v);
    }
    const envValue = Number(process.env.SEED_PER_TYPE);
    if (Number.isFinite(envValue) && envValue > 0) return Math.floor(envValue);
    return 100;
  })();

  return { clean, perType: perTypeFromArg };
}

function nowEpochSec(): bigint {
  return BigInt(Math.floor(Date.now() / 1000));
}

function randInt(min: number, max: number): number {
  // inclusive range
  return Math.floor(Math.random() * (max - min + 1)) + min;
}

function pick<T>(arr: readonly T[]): T {
  return arr[randInt(0, arr.length - 1)];
}

function clampLen(s: string, maxLen: number): string {
  return s.length <= maxLen ? s : s.slice(0, maxLen);
}

function makeShortLabel(prefix: string, maxLen = 20): string {
  const tail = randInt(1, 9999).toString().padStart(4, '0');
  return clampLen(`${prefix}${tail}`, maxLen);
}

function makeCoverKey(adType: AdType, idx: number): string {
  const n = String(idx + 1).padStart(3, '0');
  return `ads/${adType.toLowerCase()}/img_${n}.png`;
}

function makeAdsUrl(adType: AdType): string {
  const id = randInt(100000, 999999);
  return `https://example.com/ads/${adType.toLowerCase()}?c=${id}`;
}

function makeContent(adType: AdType): string {
  const phrases = [
    '限时优惠',
    '新人专享',
    '立即领取',
    '官方推荐',
    '热卖爆款',
    '今日必看',
    '立刻参与',
    '福利放送',
    '超值精选',
    '品质保证',
  ] as const;

  const base = `${pick(phrases)} · ${adType}`;
  const extra = `｜${pick(phrases)}｜编号${randInt(1000, 9999)}`;
  return clampLen(base + extra, 500);
}

function makeTimeWindow(): { startDt: bigint; expiryDt: bigint } {
  const now = Number(nowEpochSec());
  const startOffsetDays = randInt(-30, 30);
  const start = now + startOffsetDays * 86400;
  const durationDays = randInt(7, 90);
  const expiry = start + durationDays * 86400;
  return { startDt: BigInt(start), expiryDt: BigInt(expiry) };
}

async function main() {
  const args = parseArgs(process.argv.slice(2));
  const tsNow = nowEpochSec();
  const adTypes = Object.values(AdType) as AdType[];

  if (args.clean) {
    await prisma.ads.deleteMany();
    console.log('[seed:ads] cleaned ads collection');
  }

  const advertiserPrefixes = [
    '广告商A',
    '广告商B',
    '广告商C',
    '品牌X',
    '品牌Y',
    '品牌Z',
  ] as const;

  const titlePrefixes = [
    '爆款推荐',
    '限时福利',
    '新品上线',
    '今日热推',
    '官方活动',
    '专属礼包',
  ] as const;

  const batch: Prisma.AdsCreateManyInput[] = [];

  for (const adType of adTypes) {
    for (let idx = 0; idx < args.perType; idx++) {
      const { startDt, expiryDt } = makeTimeWindow();
      const advertiser = makeShortLabel(pick(advertiserPrefixes), 20);
      const title = makeShortLabel(pick(titlePrefixes), 20);
      const adsCoverImg =
        Math.random() < 0.85 ? makeCoverKey(adType, idx) : null;
      const adsUrl = Math.random() < 0.9 ? makeAdsUrl(adType) : null;
      const adsContent = Math.random() < 0.8 ? makeContent(adType) : null;

      batch.push({
        adType,
        advertiser,
        title,
        adsContent,
        adsCoverImg,
        adsUrl,
        imgSource: ImageSource.LOCAL_ONLY,
        startDt,
        expiryDt,
        seq: randInt(0, 9999),
        status: Math.random() < 0.9 ? 1 : 0,
        createAt: tsNow,
        updateAt: tsNow,
      });
    }
  }

  const result = await prisma.ads.createMany({ data: batch });
  console.log(
    `[seed:ads] adTypes=${adTypes.length} perType=${args.perType} inserted=${result.count} clean=${args.clean}`,
  );
}

main()
  .catch((error) => {
    console.error('[seed:ads] failed:', error);
    process.exitCode = 1;
  })
  .finally(async () => {
    await prisma.$disconnect();
  });