const core = require('@actions/core')
const exec = require('@actions/exec')
const assert = require('assert')

const { GITHUB_REPOSITORY, GITHUB_REF, ENV } = process.env

const branch = GITHUB_REF.replace('refs/heads/', '')

module.exports = new (class Git {

  commandsRun = []

  constructor() {
    const githubToken = core.getInput('github-token', { required: true })

    // Make the Github token secret
    core.setSecret(githubToken)

    const gitUserName = core.getInput('git-user-name')
    const gitUserEmail = core.getInput('git-user-email')

    // if the env is dont-use-git then we mock exec as we are testing a workflow
    if (ENV === 'dont-use-git') {
      this.exec = (command) => {
        const fullCommand = `git ${command}`

        console.log(`Skipping "${fullCommand}" because of test env`)

        if (!fullCommand.includes('git remote set-url origin')) {
          this.commandsRun.push(fullCommand)
        }
      }
    }

    // Set config
    this.config('user.name', gitUserName)
    this.config('user.email', gitUserEmail)

    // Update the origin
    this.updateOrigin(`https://x-access-token:${githubToken}@github.com/${GITHUB_REPOSITORY}.git`)
  }

  /**
   * Executes the git command
   *
   * @param command
   * @return {Promise<>}
   */
  exec = (command) => new Promise(async(resolve, reject) => {
    const exitCode = await exec.exec(`git ${command}`)

    if (exitCode === 0) {
      resolve()

    } else {
      reject(`Command "git ${command}" exited with code ${exitCode}.`)
    }
  })

  /**
   * Set a git config prop
   *
   * @param prop
   * @param value
   * @return {Promise<>}
   */
  config = (prop, value) => this.exec(`config ${prop} "${value}"`)

  /**
   * Add a file to commit
   *
   * @param file
   * @returns {*}
   */
  add = (file) => this.exec(`add ${file}`)

  /**
   * Commit all changes
   *
   * @param message
   *
   * @return {Promise<>}
   */
  commit = (message) => (
    this.exec(`commit -m "${message}"`)
  )

  /**
   * Pull the full history
   *
   * @return {Promise<>}
   */
  pull = async() => {
    const args = ['pull']

    // Check if the repo is unshallow
    if (await this.isShallow()) {
      args.push('--unshallow')
    }

    args.push('--tags')
    args.push(core.getInput('git-pull-method'))

    return this.exec(args.join(' '))
  }

  /**
   * Push all changes
   *
   * @return {Promise<>}
   */
  push = () => (
    this.exec(`push origin ${branch} --follow-tags`)
  )

  /**
   * Check if the repo is shallow
   *
   * @return {Promise<>}
   */
  isShallow = async() => {
    const isShallow = await this.exec('rev-parse --is-shallow-repository')

    // isShallow does not return anything on local machine
    if (isShallow) {
      return isShallow.trim().replace('\n', '') === 'true'
    } else {
      return false
    }
  }

  /**
   * Updates the origin remote
   *
   * @param repo
   * @return {Promise<>}
   */
  updateOrigin = (repo) => this.exec(`remote set-url origin ${repo}`)

  /**
   * Creates git tag
   *
   * @param tag
   * @return {Promise<>}
   */
  createTag = (tag) => this.exec(`tag -a ${tag} -m "${tag}"`)

  /**
   * Validates the commands run
   */
  testHistory = () => {
    if (ENV === 'dont-use-git') {
      const { EXPECTED_TAG, SKIPPED_COMMIT } = process.env

      const expectedCommands = [
        'git config user.name "Conventional Changelog Action"',
        'git config user.email "conventional.changelog.action@github.com"',
        'git rev-parse --is-shallow-repository',
        'git pull --tags --ff-only',
      ]

      if (!SKIPPED_COMMIT) {
        expectedCommands.push('git add .')
        expectedCommands.push(`git commit -m "chore(release): ${EXPECTED_TAG}"`)
      }

      expectedCommands.push(`git tag -a ${EXPECTED_TAG} -m "${EXPECTED_TAG}"`)
      expectedCommands.push(`git push origin ${branch} --follow-tags`)

      assert.deepStrictEqual(
        this.commandsRun,
        expectedCommands,
      )
    }
  }

})()