import { writeFileSync } from 'fs';
import { dedent } from 'tslint/lib/utils';
import { promisify } from 'util';
import * as child from 'child_process';
const exec = promisify(child.exec);

async function createVersionsFile(filename: string) {
    const tag = (await exec('git describe --tags')).stdout.toString().trim();
    const revision = (await exec('git rev-parse --short HEAD')).stdout.toString().trim();
    const branch = (await exec('git rev-parse --abbrev-ref HEAD')).stdout.toString().trim();

    console.log(`version: '${process.env.npm_package_version}', revision: '${revision}', branch: '${branch}'`);

    const content = dedent`
      // this file is automatically generated by git.version.ts script
      export const versions = {
        version: '${tag}',
        revision: '${revision}',
        branch: '${branch}'
      };`;

    writeFileSync(filename, content, {encoding: 'utf8'});
}

createVersionsFile('src/environments/versions.ts');