post_checkout: &post_checkout
  run:
    name: Checkout submodule and get changed files
    command: |
        git submodule sync
        git submodule update --init --recursive
        if [[ $CIRCLE_PULL_REQUEST ]]; then
          BASE_COMMIT=$(curl -s -H "Authorization: token a61ecb2fc5b72da54431""1b3db3875c96854958a8" \
            https://api.github.com/repos/$CIRCLE_PROJECT_USERNAME/$CIRCLE_PROJECT_REPONAME/pulls/$CIRCLE_PR_NUMBER \
            | jq -r ".base.sha | select(. != null)")...
        else
          BASE_COMMIT=HEAD^
        fi
        if [[ $BASE_COMMIT ]]; then
          CHANGED=$(git diff --name-only $BASE_COMMIT)
          echo "$CHANGED"
          echo "export CHANGED=\"$CHANGED\"" >> $BASH_ENV
        fi

node_modules_cache_key: &node_modules_cache_key
  yarn-deps-v1-{{ checksum "yarn.lock" }}

restore_node_modules_cache: &restore_node_modules_cache
  restore_cache:
    keys:
      - *node_modules_cache_key
      - yarn-deps-v1-

yarn_install: &yarn_install
  run:
    name: Install dependencies
    command: yarn

codecov: &codecov
  run:
    name: Upload code coverage reports to Codecov
    command: ./node_modules/.bin/codecov

screenshotter: &screenshotter
  steps:
    - checkout
    - *post_checkout
    - run:
        name: Skip screenshotter if no KaTeX code has been changed
        command: |
            if [[ $CHANGED ]]; then
              echo "$CHANGED" | grep -qvE '^contrib/|^docs/|^static/|^website/|^LICENSE|\.md$' || circleci step halt
            fi

    - *restore_node_modules_cache
    - *yarn_install

    - run:
        name: Verify screenshots and generate diffs and new screenshots
        command: node dockers/screenshotter/screenshotter.js --selenium-ip localhost -b $CIRCLE_JOB --verify --diff --new --coverage
    - *codecov

    - store_artifacts:
        path: test/screenshotter/new
        destination: new
    - store_artifacts:
        path: test/screenshotter/diff
        destination: diff

version: 2
jobs:
  test:
    docker:
      - image: circleci/node:6
    steps:
      - run:
          name: Check whether the build is running on the main repository
          command: |
              if [[ $CIRCLE_PULL_REQUEST && $CIRCLE_PROJECT_USERNAME != "Khan" ]]; then
                echo "Please disable CircleCI on your forked repository!"
                exit 1
              fi

      - checkout
      - *post_checkout
      - run:
          name: Skip screenshotter if only documentation has been changed
          command: |
              if [[ $CHANGED ]]; then
                echo "$CHANGED" | grep -qvE '^docs/|^LICENSE|\.md$' || circleci step halt
              fi

      - *restore_node_modules_cache
      - *yarn_install
      - save_cache:
          key: *node_modules_cache_key
          paths:
            - node_modules

      - add_ssh_keys:
          fingerprints:
            - "e1:ac:13:98:98:8b:fd:38:81:12:28:55:75:a1:da:73"
      - run:
          name: Greenkeeper - update and commit yarn.lock
          command: |
              ./node_modules/.bin/greenkeeper-lockfile-update
              ./node_modules/.bin/greenkeeper-lockfile-upload

      - run:
          name: Run tests
          command: yarn test --coverage
      - *codecov

      - run:
          name: Build KaTeX
          command: USE_TTF=false yarn build

      - store_artifacts:
          path: dist/katex.min.js
          destination: katex.min.js
      - store_artifacts:
          path: dist/katex.min.css
          destination: katex.min.css
      - store_artifacts:
          path: dist/fonts
          destination: fonts

  firefox:
    docker:
      - image: circleci/node:6
      - image: selenium/standalone-firefox:2.48.2
    <<: *screenshotter
  chrome:
    docker:
      - image: circleci/node:6
      - image: selenium/standalone-chrome:2.48.2
        environment:
          DBUS_SESSION_BUS_ADDRESS: /dev/null
    <<: *screenshotter

workflows:
  version: 2
  test:
    jobs:
      - test
      - firefox
      - chrome