#!/usr/bin/env node

const shell = require('shelljs');
shell.config.fatal = true;
const util = require('./utils/git_util');

if (require.main === module) {
  main(process.argv.splice(2)).then(
    (v) => process.exitCode, 
    (e) => console.error(process.exitCode = 1, e) 
  );
}

async function main(args) {
  let flags = '';
  let prNumber = 0;
  let printHelp = false;

  args.forEach((arg) => {
    if (prNumber == 0 && Number.parseInt(arg) > 0) {
      prNumber = Number.parseInt(arg);
    } else if (arg == '--help') {
      printHelp = true;
    } else if (arg == '--force-with-lease') {
      flags += ' --force-with-lease';
    } else if (arg == '--force') {
      flags += ' --force';
    } else {
      shell.echo('Unexpected argument: ', arg);
    }
  });

  if (!prNumber) {
    const branch = util.getCurrentBranch();
    const maybePr = branch.split('/')[1];
    if (maybePr > 0) {
      shell.echo(`PR number not specified. Defaulting to #${maybePr}.`);
      prNumber = maybePr;
    }
  }

  if (!prNumber || printHelp) {
    shell.echo(`Push the current HEAD into an existing pull request.`);
    shell.echo(``);
    shell.echo(`${process.argv[1]} [PR_NUMBER] [--force-with-lease]`);
    shell.echo(``);
    shell.echo(`    --force-with-lease    Continues even \if change can\'t be fast-forwarded.`);
    shell.echo(`    --force               Forces the push with --force.`);
    shell.echo(`    [PR_NUMBER]           If not present the script guesses the PR from the branch name.`);
    return 1;
  }

  const prInfo = await util.githubPrInfo(prNumber);
  const prPushCmd = `git push${flags} ${prInfo.repository.gitUrl} HEAD:${prInfo.branch}`;
  shell.echo(`>>> ${prPushCmd}`);
  shell.exec(prPushCmd);

  return 0;
 }