/**
 * Webpack Bundle Unpacker & Module Extractor
 * -------------------------------------------
 * 依据 AGENTS.md §2.2 L1/L2 规范，将 Webpack 单文件打包解包为独立可读的模块文件。
 */

const fs = require("fs");
const path = require("path");
const parser = require("@babel/parser");
const generate = require("@babel/generator").default;

function unpackBundle(bundlePath, outputDir) {
  const code = fs.readFileSync(bundlePath, "utf-8");
  console.log(`Parsing bundle ${bundlePath} (${code.length} bytes)...`);
  const ast = parser.parse(code, { sourceType: "script" });

  const call = ast.program.body[0].expression.argument;
  const modulesArray = call.arguments[0].elements;
  console.log(`Found ${modulesArray.length} modules.`);

  fs.mkdirSync(outputDir, { recursive: true });

  const index = [];

  modulesArray.forEach((modNode, idx) => {
    if (!modNode) {
      index.push({ id: idx, empty: true });
      return;
    }
    const modCode = generate(modNode).code;
    const modFile = path.join(outputDir, `module_${idx.toString().padStart(3, "0")}.js`);
    fs.writeFileSync(modFile, modCode, "utf-8");

    // Search keywords in module to create index
    const keywords = [];
    if (/verify/i.test(modCode)) keywords.push("verify");
    if (/pow/i.test(modCode)) keywords.push("pow");
    if (/tdc/i.test(modCode)) keywords.push("tdc");
    if (/collect/i.test(modCode)) keywords.push("collect");
    if (/getsig/i.test(modCode)) keywords.push("getsig");
    if (/prehandle/i.test(modCode)) keywords.push("prehandle");
    if (/subcapclass/i.test(modCode)) keywords.push("subcapclass");
    if (/ticket/i.test(modCode)) keywords.push("ticket");

    index.push({
      id: idx,
      size: modCode.length,
      file: `module_${idx.toString().padStart(3, "0")}.js`,
      keywords,
    });
  });

  const indexFile = path.join(outputDir, "manifest.json");
  fs.writeFileSync(indexFile, JSON.stringify(index, null, 2), "utf-8");
  console.log(`Manifest written to ${indexFile}`);

  return index;
}

if (require.main === module) {
  const bundle = process.argv[2] || "tcaptcha/core_js/tcaptcha-frame.ba387dd1.js";
  const outDir = process.argv[3] || "tcaptcha/core_js/frame_modules";
  unpackBundle(bundle, outDir);
}

module.exports = { unpackBundle };