name: Deploy

on:
  push:
    branches: master
  release:
    types: [created]

env:
  TARGET_BRANCH: 'gh-pages'
  SHA: '${{ github.sha }}'
  SSH_REPO: 'git@github.com:${{ github.repository }}.git'
  TAG_NAME: '${{ github.event.release.GITHUB_REF }}'

jobs:
  deploy:
    runs-on: ubuntu-latest

    steps:
    - name: Checkout
      uses: actions/checkout@v2.0.0
    - name: Checkout
      uses: actions/checkout@v2.0.0
      with:
        ref: ${{ env.TARGET_BRANCH }}
        path: 'out'
    - name: Deploy
      run: |
        set -ex

        echo "Removing the current docs for master"
        rm -rf out/master/ || exit 0

        echo "Making the docs for master"
        mkdir out/master/
        cp util/gh-pages/index.html out/master
        python ./util/export.py out/master/lints.json

        if [[ -n $TAG_NAME ]]; then
          echo "Save the doc for the current tag ($TAG_NAME) and point current/ to it"
          cp -r out/master "out/$TAG_NAME"
          rm -f out/current
          ln -s "$TAG_NAME" out/current
        fi

        # Generate version index that is shown as root index page
        cp util/gh-pages/versions.html out/index.html

        cd out
        cat <<-EOF | python - > versions.json
        import os, json
        print json.dumps([
            dir for dir in os.listdir(".") if not dir.startswith(".") and os.path.isdir(dir)
        ])
        EOF

        # Now let's go have some fun with the cloned repo
        git config user.name "GHA CI"
        git config user.email "gha@ci.invalid"

        if git diff --exit-code --quiet; then
            echo "No changes to the output on this push; exiting."
            exit 0
        fi

        git add .
        git commit -m "Automatic deploy to GitHub Pages: ${SHA}"

        eval "$(ssh-agent -s)"
        ssh-add - <<< "${{ secrets.DEPLOY_KEY }}"

        git push "$SSH_REPO" "$TARGET_BRANCH"