#!/usr/bin/env node

const fs = require("fs");
const childProcess = require("child_process");
const { promisify } = require("util");

const exec = promisify(childProcess.exec);
const readFile = promisify(fs.readFile);
const writeFile = promisify(fs.writeFile);

const [, , commitMsg, comitSrc, sha1] = process.argv;

async function main() {
  const file = await readFile(commitMsg, { encoding: "utf8" });
  const result = await exec("git symbolic-ref --short HEAD");

  const tags = result.stdout
    .split("\n")
    .map(branch => branch.match(/[A-Z]+-\d+/g))
    .filter(x => !!x)
    .reduce((allIDs, matchedIDs) => [...allIDs, ...matchedIDs], [])
    .map(id => `[${id}]`);

  if (tags.length === 0) {
    return;
  }
  if (tags.find(tag => file.includes(tag))) {
    return;
  }
  const newFile = "\n\n# " + tags.join(" ") + "\n" + file;
  await writeFile(commitMsg, newFile);
}

main().catch(err => {
  console.error(err);
  process.exit(1);
});