red-note-api/src/help.js

Parse the Xiaohongshu API

// noinspection all

const lookup = [
  "Z",
  "m",
  "s",
  "e",
  "r",
  "b",
  "B",
  "o",
  "H",
  "Q",
  "t",
  "N",
  "P",
  "+",
  "w",
  "O",
  "c",
  "z",
  "a",
  "/",
  "L",
  "p",
  "n",
  "g",
  "G",
  "8",
  "y",
  "J",
  "q",
  "4",
  "2",
  "K",
  "W",
  "Y",
  "j",
  "0",
  "D",
  "S",
  "f",
  "d",
  "i",
  "k",
  "x",
  "3",
  "V",
  "T",
  "1",
  "6",
  "I",
  "l",
  "U",
  "A",
  "F",
  "M",
  "9",
  "7",
  "h",
  "E",
  "C",
  "v",
  "u",
  "R",
  "X",
  "5",
];

function encodeUtf8(e) {
  const b = [];
  const m = encodeURIComponent(e).replace(/[!'()*]/g, (c) => `%${c.charCodeAt(0).toString(16).toUpperCase()}`);
  let w = 0;

  while (w < m.length) {
    const T = m[w];
    if (T === "%") {
      const E = m.slice(w + 1, w + 3);
      const S = parseInt(E, 16);
      b.push(S);
      w += 2;
    } else {
      b.push(T.charCodeAt(0));
    }
    w += 1;
  }

  return b;
}

function mrc(e) {
  const ie = [
    0, 1996959894, 3993919788, 2567524794, 124634137, 1886057615, 3915621685, 2657392035, 249268274, 2044508324,
    3772115230, 2547177864, 162941995, 2125561021, 3887607047, 2428444049, 498536548, 1789927666, 4089016648,
    2227061214, 450548861, 1843258603, 4107580753, 2211677639, 325883990, 1684777152, 4251122042, 2321926636, 335633487,
    1661365465, 4195302755, 2366115317, 997073096, 1281953886, 3579855332, 2724688242, 1006888145, 1258607687,
    3524101629, 2768942443, 901097722, 1119000684, 3686517206, 2898065728, 853044451, 1172266101, 3705015759,
    2882616665, 651767980, 1373503546, 3369554304, 3218104598, 565507253, 1454621731, 3485111705, 3099436303, 671266974,
    1594198024, 3322730930, 2970347812, 795835527, 1483230225, 3244367275, 3060149565, 1994146192, 31158534, 2563907772,
    4023717930, 1907459465, 112637215, 2680153253, 3904427059, 2013776290, 251722036, 2517215374, 3775830040,
    2137656763, 141376813, 2439277719, 3865271297, 1802195444, 476864866, 2238001368, 4066508878, 1812370925, 453092731,
    2181625025, 4111451223, 1706088902, 314042704, 2344532202, 4240017532, 1658658271, 366619977, 2362670323,
    4224994405, 1303535960, 984961486, 2747007092, 3569037538, 1256170817, 1037604311, 2765210733, 3554079995,
    1131014506, 879679996, 2909243462, 3663771856, 1141124467, 855842277, 2852801631, 3708648649, 1342533948, 654459306,
    3188396048, 3373015174, 1466479909, 544179635, 3110523913, 3462522015, 1591671054, 702138776, 2966460450,
    3352799412, 1504918807, 783551873, 3082640443, 3233442989, 3988292384, 2596254646, 62317068, 1957810842, 3939845945,
    2647816111, 81470997, 1943803523, 3814918930, 2489596804, 225274430, 2053790376, 3826175755, 2466906013, 167816743,
    2097651377, 4027552580, 2265490386, 503444072, 1762050814, 4150417245, 2154129355, 426522225, 1852507879,
    4275313526, 2312317920, 282753626, 1742555852, 4189708143, 2394877945, 397917763, 1622183637, 3604390888,
    2714866558, 953729732, 1340076626, 3518719985, 2797360999, 1068828381, 1219638859, 3624741850, 2936675148,
    906185462, 1090812512, 3747672003, 2825379669, 829329135, 1181335161, 3412177804, 3160834842, 628085408, 1382605366,
    3423369109, 3138078467, 570562233, 1426400815, 3317316542, 2998733608, 733239954, 1555261956, 3268935591,
    3050360625, 752459403, 1541320221, 2607071920, 3965973030, 1969922972, 40735498, 2617837225, 3943577151, 1913087877,
    83908371, 2512341634, 3803740692, 2075208622, 213261112, 2463272603, 3855990285, 2094854071, 198958881, 2262029012,
    4057260610, 1759359992, 534414190, 2176718541, 4139329115, 1873836001, 414664567, 2282248934, 4279200368,
    1711684554, 285281116, 2405801727, 4167216745, 1634467795, 376229701, 2685067896, 3608007406, 1308918612, 956543938,
    2808555105, 3495958263, 1231636301, 1047427035, 2932959818, 3654703836, 1088359270, 936918000, 2847714899,
    3736837829, 1202900863, 817233897, 3183342108, 3401237130, 1404277552, 615818150, 3134207493, 3453421203,
    1423857449, 601450431, 3009837614, 3294710456, 1567103746, 711928724, 3020668471, 3272380065, 1510334235, 755167117,
  ];
  let o = -1;

  function rightWithoutSign(num, bit = 0) {
    return (num >>> bit) | 0;
  }

  for (let n = 0; n < 57; n++) {
    o = ie[(o & 255) ^ e.charCodeAt(n)] ^ rightWithoutSign(o, 8);
  }
  return o ^ -1 ^ 3988292384;
}

function encodeChunk(e, t, r) {
  const m = [];
  for (let b = t; b < r; b += 3) {
    const n = (16711680 & (e[b] << 16)) + ((e[b + 1] << 8) & 65280) + (e[b + 2] & 255);
    m.push(tripletToBase64(n));
  }
  return m.join("");
}

function tripletToBase64(e) {
  return lookup[63 & (e >> 18)] + lookup[63 & (e >> 12)] + lookup[(e >> 6) & 63] + lookup[e & 63];
}
function b64Encode(e) {
  const P = e.length;
  const W = P % 3;
  const U = [];
  const z = 16383;
  let H = 0;
  const Z = P - W;

  while (H < Z) {
    U.push(encodeChunk(e, H, Math.min(H + z, Z)));
    H += z;
  }

  if (W === 1) {
    const F = e[P - 1];
    U.push(lookup[F >> 2] + lookup[(F << 4) & 63] + "==");
  } else if (W === 2) {
    const F = (e[P - 2] << 8) + e[P - 1];
    U.push(lookup[F >> 10] + lookup[63 & (F >> 4)] + lookup[(F << 2) & 63] + "=");
  }

  return U.join("");
}

module.exports = {
  getXCommon,
  encodeUtf8,
  mrc,
  encodeChunk,
};

function getXCommon(a1 = "", b1 = "", xS = undefined, xT = undefined) {
  const common = {
    s0: 5, // getPlatformCode
    s1: "",
    x0: "1", // localStorage.getItem("b1b1")
    x1: "3.7.8-2", // version
    x2: "Windows",
    x3: "xhs-pc-web",
    x4: "4.27.7",
    x5: a1, // cookie of a1
    x6: xT,
    x7: xS,
    x8: b1, // localStorage.getItem("b1")
    x9: mrc(xT + xS + b1),
    x10: 1, // getSigCount
  };
  const encodeStr = encodeUtf8(JSON.stringify(common));
  const x_s_common = b64Encode(encodeStr);
  return x_s_common;
}

function getRequestId() {
  const e = Math.random().toString().slice(2, 11);
  const t = new Date().getTime();
  return e + "-" + t;
}

function getSearchId() {
  const e = BigInt(Date.now()) << 64n;
  const t = Math.floor(Math.random() * 2147483647);
  return base36encode(e + BigInt(t));
}

function base36encode(num) {
  return num.toString(36).toUpperCase();
}
const SearchSortType = Object.freeze({
  // default
  GENERAL: { value: "general" },
  // most popular
  MOST_POPULAR: { value: "popularity_descending" },
  // Latest
  LATEST: { value: "time_descending" },
});

const SearchNoteType = Object.freeze({
  // default
  ALL: { value: 0 },
  // only video
  VIDEO: { value: 1 },
  // only image
  IMAGE: { value: 2 },
});

module.exports = {
  getXCommon,
  encodeUtf8,
  mrc,
  encodeChunk,
  getRequestId,
  getSearchId,
  SearchSortType,
  SearchNoteType,
};