#!/usr/bin/env node
/**
 * aplmate.js - Wrapper/scraper aplmate.com (Apple Music -> MP3)
 * Node.js >= 18 (ESM, tanpa dependency)
 *
 * CLI    : node aplmate.js https://music.apple.com/id/song/nicole-kidman/6792884088
 * Module : import aplmate from "./aplmate.js"; console.log(await aplmate(link));
 */

import { writeFile } from "node:fs/promises";
import { pathToFileURL } from "node:url";

const BASE = "https://aplmate.com";
const DEFAULT_UA =
  "Mozilla/5.0 (Linux; Android 10; K) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/140.0.0.0 Safari/537.36";

const SERVER_MESSAGES = {
  post_required: "Form harus disubmit.",
  invalid_input: "Masukkan judul/artis atau link Apple Music yang valid.",
  session_error: "Gagal memulai sesi download.",
  rate_limit: "Request terlalu cepat, tunggu 5 detik.",
  details_unavailable: "Detail lagu gagal dimuat.",
  no_results: "Lagu tidak ditemukan.",
  link_not_found: "Link Apple Music tidak ditemukan.",
  no_tracks: "Tidak ada lagu pada link ini.",
  invalid_track: "Data track tidak valid, cari ulang.",
  generic_error: "Terjadi kesalahan di server.",
};

export class AplMateError extends Error {
  constructor(message, extra = {}) {
    super(message);
    this.name = "AplMateError";
    Object.assign(this, extra);
  }
}

/* ------------------------------ helpers ------------------------------ */

const sleep = (ms) => new Promise((r) => setTimeout(r, ms));

const decodeEntities = (s = "") =>
  s
    .replace(/&#x([0-9a-f]+);/gi, (_, h) => String.fromCodePoint(parseInt(h, 16)))
    .replace(/&#(\d+);/g, (_, d) => String.fromCodePoint(+d))
    .replace(/"/g, '"')
    .replace(/'|'/g, "'")
    .replace(/&lt;/g, "<")
    .replace(/&gt;/g, ">")
    .replace(/&amp;/g, "&");

const attr = (tag, name) => {
  const m = tag.match(new RegExp(`\\b${name}\\s*=\\s*(?:"([^"]*)"|'([^']*)')`, "i"));
  return m ? m[1] ?? m[2] : null;
};

const stripTags = (s = "") => decodeEntities(s.replace(/<[^>]+>/g, " ")).replace(/\s+/g, " ").trim();

function jwtPayload(token) {
  try {
    const part = token.split(".")[1].replace(/-/g, "+").replace(/_/g, "/");
    return JSON.parse(Buffer.from(part, "base64").toString("utf8"));
  } catch {
    return null;
  }
}

/* ------------------------------ parsers ------------------------------ */

/** Ambil semua form /action/track dari HTML hasil link. */
export function parseTracks(html) {
  const out = [];
  const re = /<form\b[^>]*action=["']\/action\/track["'][^>]*>([\s\S]*?)<\/form>/gi;
  let m;
  while ((m = re.exec(html))) {
    const form = {};
    for (const i of m[1].matchAll(/<input\b[^>]*>/gi)) {
      const name = attr(i[0], "name");
      if (name) form[name] = decodeEntities(attr(i[0], "value") ?? "");
    }
    if (!form.data) continue;
    let meta = {};
    try {
      meta = JSON.parse(Buffer.from(form.data, "base64").toString("utf8"));
    } catch {}
    out.push({ form, meta });
  }
  return out;
}

/** Ambil link download (mp3, cover HD, lossless) dari HTML hasil /action/track. */
export function parseDownloads(html) {
  const d = { mp3: null, cover_hd: null, lossless_page: null, filename: null, expires_at: null, expires_in: null };
  for (const m of html.matchAll(/<a\b([^>]*)>([\s\S]*?)<\/a>/gi)) {
    const href = decodeEntities(attr(m[1], "href") ?? "");
    const label = stripTags(m[2]);
    if (!href) continue;

    if (/^https?:\/\/cdndl\.aplmate\.com\//i.test(href)) {
      let claims = null;
      try {
        claims = jwtPayload(new URL(href).searchParams.get("token") ?? "");
      } catch {}
      if (/cover/i.test(label) || claims?.cover) {
        d.cover_hd ??= href;
      } else {
        d.mp3 ??= href;
        if (claims?.filename) d.filename = `${claims.filename}.mp3`;
        if (claims?.exp) {
          d.expires_at = new Date(claims.exp * 1000).toISOString();
          if (claims.iat) d.expires_in = claims.exp - claims.iat;
        }
      }
    } else if (/lossless/i.test(label)) {
      d.lossless_page ??= href;
    }
  }
  return d;
}

/** Fallback metadata kalau respons langsung berupa kartu download (tanpa form track). */
function parseCard(html) {
  const pick = (re) => decodeEntities((html.match(re) || [])[1] ?? "") || null;
  return {
    id: null,
    title: pick(/<h3[^>]*>\s*<div[^>]*title="([^"]*)"/i),
    artist: pick(/<p>\s*<span>([\s\S]*?)<\/span>\s*<\/p>/i),
    album: null,
    duration: null,
    cover: pick(/aplmate-downloader-left[\s\S]*?<img[^>]*src="([^"]+)"/i),
  };
}

const parseHeading = (html) =>
  decodeEntities((html.match(/<h3[^>]*>\s*<div[^>]*title="([^"]*)"/i) || [])[1] ?? "") || null;

/* ------------------------------ client ------------------------------ */

export class AplMate {
  /**
   * @param {object}  o
   * @param {string}  [o.lang="en"]
   * @param {string}  [o.turnstile]  token cf-turnstile-response (default: env APLMATE_TURNSTILE)
   * @param {string}  [o.cookie]     header Cookie mentah (mis. "cf_clearance=...")
   * @param {string}  [o.userAgent]  samakan dengan UA browser kalau pakai cf_clearance
   * @param {number}  [o.delay=5000] jeda antar request /action/track (ms)
   * @param {number}  [o.timeout=30000]
   */
  constructor(o = {}) {
    this.lang = o.lang ?? "en";
    this.turnstile = o.turnstile ?? process.env.APLMATE_TURNSTILE ?? null;
    this.cookie = o.cookie ?? process.env.APLMATE_COOKIE ?? null;
    this.userAgent = o.userAgent ?? process.env.APLMATE_UA ?? DEFAULT_UA;
    this.delay = o.delay ?? 5000;
    this.timeout = o.timeout ?? 30000;
    this.jar = new Map();
  }

  #cookieHeader() {
    const parts = [...this.jar].map(([k, v]) => `${k}=${v}`);
    if (this.cookie) parts.unshift(this.cookie);
    return parts.join("; ");
  }

  #storeCookies(res) {
    for (const c of res.headers.getSetCookie?.() ?? []) {
      const [kv] = c.split(";");
      const i = kv.indexOf("=");
      if (i > 0) this.jar.set(kv.slice(0, i).trim(), kv.slice(i + 1).trim());
    }
  }

  async #post(path, body, extra = {}) {
    const headers = {
      "user-agent": this.userAgent,
      accept: "*/*",
      "accept-language": "en-US,en;q=0.9",
      origin: BASE,
      referer: `${BASE}/`,
      ...extra,
    };
    const ck = this.#cookieHeader();
    if (ck) headers.cookie = ck;
    const res = await fetch(BASE + path, {
      method: "POST",
      headers,
      body,
      signal: AbortSignal.timeout(this.timeout),
    });
    this.#storeCookies(res);
    return { res, text: await res.text() };
  }

  #json({ res, text }) {
    try {
      return JSON.parse(text);
    } catch {
      const blocked = res.status === 403 || /just a moment|cloudflare/i.test(text);
      throw new AplMateError(
        blocked
          ? `Diblokir Cloudflare (HTTP ${res.status}). Pakai --cookie (cf_clearance) dan --ua dari browser yang sama.`
          : `Respons bukan JSON (HTTP ${res.status}).`,
        { code: blocked ? "CLOUDFLARE_BLOCKED" : "BAD_RESPONSE", status: res.status }
      );
    }
  }

  #fail(j) {
    const raw = j.error ?? j.message ?? j.msg ?? j.code ?? "";
    const key = typeof raw === "string" ? raw : "";
    const msg = SERVER_MESSAGES[key] ?? (key ? stripTags(key) : "Server menolak request.");
    return new AplMateError(msg, { code: key || "SERVER_ERROR", raw: j });
  }

  /** Minta token sesi dari endpoint userverify milik situs (dipakai browser untuk link). */
  async verify(url) {
    try {
      const r = await this.#post(
        "/action/userverify",
        new URLSearchParams({ url, lang: this.lang }),
        { "x-requested-with": "XMLHttpRequest" }
      );
      return r.text.match(/JWT\.[A-Za-z0-9_.-]+/)?.[0] ?? null;
    } catch {
      return null;
    }
  }

  /** Link -> HTML daftar track (atau kartu download langsung). */
  async lookup(input) {
    const token = (await this.verify(input)) ?? this.turnstile;
    if (!token) {
      throw new AplMateError(
        "Token Turnstile dibutuhkan. Ambil dari browser lalu kirim lewat --turnstile atau env APLMATE_TURNSTILE (lihat README).",
        { code: "TURNSTILE_REQUIRED" }
      );
    }

    for (let attempt = 0; attempt < 2; attempt++) {
      const fd = new FormData();
      fd.append("lang", this.lang);
      fd.append("url", input);
      fd.append("cf-turnstile-response", token);
      const j = this.#json(await this.#post("/action", fd));
      if (j.success && typeof j.html === "string") return { html: j.html };

      const err = this.#fail(j);
      if (attempt === 0 && /rate_limit|too fast/i.test(`${err.code} ${err.message}`)) {
        await sleep(5000);
        continue;
      }
      throw err;
    }
  }

  /** Satu track (form hidden hasil parseTracks) -> link download. */
  async resolve(form) {
    for (let attempt = 0; attempt < 2; attempt++) {
      const fd = new FormData();
      fd.append("lang", this.lang);
      for (const k of ["data", "base", "token"]) fd.append(k, form[k] ?? "");
      const j = this.#json(await this.#post("/action/track", fd));
      const html = typeof j.html === "string" ? j.html : typeof j.data === "string" ? j.data : "";
      if (j.success !== false && html) {
        const dl = parseDownloads(html);
        if (dl.mp3 || dl.cover_hd) return dl;
        throw new AplMateError("Link download tidak ditemukan pada respons.", { code: "NO_LINK", raw: j });
      }
      const err = this.#fail(j);
      if (attempt === 0 && /rate_limit|too fast/i.test(`${err.code} ${err.message}`)) {
        await sleep(5000);
        continue;
      }
      throw err;
    }
  }
}

/* ------------------------------ main API ------------------------------ */

/**
 * @param {string} input  link Apple Music (lagu / album / playlist)
 * @param {object} [opts] { resolve: 1 | "all", ...opsi AplMate }
 */
export async function aplmate(input, opts = {}) {
  input = String(input ?? "").trim();
  if (!/^https?:\/\/(?:embed\.)?music\.apple\.com\//i.test(input)) {
    throw new AplMateError("Input harus berupa link Apple Music (https://music.apple.com/...).", { code: "INVALID_LINK" });
  }

  const client = new AplMate(opts);

  const { html } = await client.lookup(input);
  const parsed = parseTracks(html);
  const heading = parseHeading(html);

  let results;
  let resolved = 0;

  if (parsed.length) {
    results = parsed.map((t, i) => ({
      index: i + 1,
      id: t.meta.id ?? null,
      title: t.meta.name ?? null,
      artist: t.meta.artist ?? null,
      album: t.meta.album ?? null,
      duration: t.meta.duration ?? null,
      cover: t.meta.cover ?? null,
      url: t.meta.surl ?? t.form.base ?? null,
      download: null,
    }));

    const want = opts.resolve === "all" ? results.length : Math.max(0, Math.min(Number(opts.resolve ?? 1) || 0, results.length));
    for (let i = 0; i < want; i++) {
      if (i > 0) await sleep(client.delay);
      opts.onProgress?.(`[${i + 1}/${want}] ${results[i].title} - ${results[i].artist}`);
      try {
        results[i].download = await client.resolve(parsed[i].form);
        resolved++;
      } catch (e) {
        results[i].error = e.message;
      }
    }
  } else {
    // Respons langsung berupa kartu download
    const download = parseDownloads(html);
    if (!download.mp3 && !download.cover_hd) {
      throw new AplMateError("Tidak ada hasil untuk input tersebut.", { code: "NO_RESULTS" });
    }
    results = [{ index: 1, ...parseCard(html), url: input, download }];
    resolved = 1;
  }

  return {
    status: true,
    input,
    heading,
    total: results.length,
    resolved,
    results,
  };
}

export default aplmate;

/* ------------------------------ CLI ------------------------------ */

const HELP = `aplmate.js - Apple Music downloader wrapper (aplmate.com)

Pemakaian:
  node aplmate.js <link Apple Music> [opsi]

Opsi:
  -r, --resolve <n|all>   Album/playlist: jumlah track yang diambil link downloadnya (default: 1)
  -t, --turnstile <token> Token cf-turnstile-response (hanya jika situs memintanya)
  -c, --cookie <string>   Header Cookie mentah, mis. "cf_clearance=..." (env APLMATE_COOKIE)
      --ua <string>       User-Agent (env APLMATE_UA)
  -l, --lang <kode>       Bahasa situs (default: en)
  -d, --delay <ms>        Jeda antar track saat resolve banyak (default: 5000)
  -o, --out <file>        Simpan JSON ke file
  -h, --help              Bantuan
`;

function parseArgs(argv) {
  const o = { _: [] };
  for (let i = 0; i < argv.length; i++) {
    const a = argv[i];
    const next = () => argv[++i];
    if (a === "-r" || a === "--resolve") o.resolve = next();
    else if (a === "-t" || a === "--turnstile") o.turnstile = next();
    else if (a === "-c" || a === "--cookie") o.cookie = next();
    else if (a === "--ua") o.userAgent = next();
    else if (a === "-l" || a === "--lang") o.lang = next();
    else if (a === "-d" || a === "--delay") o.delay = Number(next());
    else if (a === "-o" || a === "--out") o.out = next();
    else if (a === "-h" || a === "--help") o.help = true;
    else o._.push(a);
  }
  return o;
}

async function cli() {
  const args = parseArgs(process.argv.slice(2));
  if (args.help || !args._.length) {
    console.log(HELP);
    return;
  }
  const { out, _, help, ...opts } = args;
  opts.onProgress = (msg) => console.error(msg);
  try {
    const result = await aplmate(_.join(" "), opts);
    const json = JSON.stringify(result, null, 2);
    if (out) await writeFile(out, json + "\n");
    console.log(json);
  } catch (e) {
    console.log(JSON.stringify({ status: false, error: e.message, code: e.code ?? "ERROR" }, null, 2));
    process.exitCode = 1;
  }
}

if (process.argv[1] && import.meta.url === pathToFileURL(process.argv[1]).href) cli();