#!/usr/bin/env node

/**
 * Generate a version table from the most recent "Release" commit,
 * for use in changelogs.
 *
 * Usage:
 *   $ ./bin/make-new-versions-table
 */

const { execSync } = require('child_process')

const logStdout = execSync('git log --grep \'Release$\' -1 --pretty=oneline --no-decorate')
let match = /^([0-9a-f]+) .*?$/m.exec(logStdout.toString())
if (!match) {
  console.error('Could not read Release commit')
  process.exit(1)
}

const commit = match[1]

const tagStdout = execSync(`git tag --list --contains ${commit}`)
const tags = tagStdout.toString()
const rx = /([@\/\w-]+)@(\d+\.\d+\.\d+)(-alpha\.\d+|-beta\.\d+)?/g

const versions = []
let m
while ((m = rx.exec(tags))) {
  const [, pkg, versionPrefix, versionSuffix] = m
  const version = `${versionPrefix}${versionSuffix || ''}`
  versions.push({ pkg, version })
}

const mid = Math.ceil(versions.length / 2)
let table = [
  '| Package | Version | Package | Version |',
  '|-|-|-|-|'
]
for (let i = 0; i < mid; i++) {
  const left = versions[i] || { pkg: '-', version: '-' }
  const right = versions[i + mid] || { pkg: '-', version: '-' }
  table.push(`| ${left.pkg} | ${left.version} | ${right.pkg} | ${right.version} |`)
}

console.log(table.join('\n'))