generate-db.js

#!/usr/bin/env node
import { readFile, writeFile } from 'node:fs/promises';
import { gunzip } from 'node:zlib';
import { join } from 'node:path';
import { promisify } from 'node:util';

const gunzipAsync = promisify(gunzip);

// TODO(@thunder-coding): Do not hardcode list of known architectures.
const archs = ["aarch64", "arm", "i686", "x86_64"];
const { TERMUX_PKG_CACHEDIR, TERMUX_PREFIX } = process.env;

if (!TERMUX_PKG_CACHEDIR) {
  throw new Error('TERMUX_PKG_CACHEDIR environment variable is not defined');
}

if (!TERMUX_PREFIX) {
  throw new Error('TERMUX_PREFIX environment variable is not defined');
}

const binPrefix = TERMUX_PREFIX.substring(1) + '/bin/';
const repos = JSON.parse(await readFile(join(TERMUX_PKG_CACHEDIR, 'repo.json')));

async function processRepo(repo) {
  for (const arch of archs) {
    const url = `${repo.url}/dists/${repo.distribution}/Contents-${arch}.gz`;
    const response = await fetch(url);

    if (!response.ok) {
      throw new Error(`${url} returned ${response.status}`);
    }

    const data = await gunzipAsync(await response.arrayBuffer());
    const binMap = {};
    data
      .toString()
      .split('\n')
      .filter(line => line.startsWith(binPrefix))
      .forEach(line => {
        const [pathToBinary, packageNames] = line.split(' ');
        const binary = pathToBinary.substring(pathToBinary.lastIndexOf('/') + 1);
        const packages = packageNames.split(',');

        packages.forEach(packageName => {
          binMap[packageName] ??= [];
          binMap[packageName].push(binary);
        });
      });

    const headerFile = `commands-${arch}-${repo.name}.h`;
    const header = Object.keys(binMap)
      .sort()
      .map(packageName => {
        const binaries = binMap[packageName].sort().map(bin => `" ${bin}",`);
        return `"${packageName}",\n${binaries.join('\n')}`;
      })
      .join('\n');

    await writeFile(headerFile, header);
  }
}

const promises = [];

for (const path in repos) {
  if (path === 'pkg_format') continue;
  const repo = repos[path];
  promises.push(processRepo(repo));
}

await Promise.all(promises);