README from docs.yaml

name: Generate README

on:
  pull_request:
    paths:
      - "docs/**/*"
  workflow_run:
    workflows:
      - "generate_help_docs"

jobs:
  make-README:
    runs-on: ubuntu-latest
    permissions:
      contents: write
    steps:
      - uses: actions/checkout@v4
      - name: Fill template
        working-directory: "docs/"
        timeout-minutes: 0.1
        run: |
          sub_doc_parts_from() {
            template="$1"
            directory="$2"

            for file in "$directory"/*; do
                if [ -f "$file" ]; then
                    placeholder="{{ $(echo "${file^^}" | tr ./ _) }}"
                    echo "Saving $file to $placeholder with expanded environment variables" >&2
                    # Export file contents to text following a pattern in template.md, e.g.:
                    # section/test_file.md would replace "{{ SECTION_TEST_FILE_MD }}""
                    template="${template//"$placeholder"/"$(<"$file")"}"
                fi
            done
            echo "$template"
          }
          sub_doc_parts_from "$(sub_doc_parts_from "$(<template.md)" "sections")" "help">../README.md
      - name: Setup git
        run: |
          git config --local user.name "github-actions[bot]"
          git config --local user.email "github-actions[bot]@users.noreply.github.com"
          git remote set-url origin https://${{ secrets.GITHUB_TOKEN }}@github.com/${{ github.repository }}
      - name: Push
        run: |
          git add README.md
          if git update-index --refresh && git diff-index --quiet HEAD --; then
            git commit -m "Automated update of README.md from docs"

            branch_name="${GITHUB_HEAD_REF:-${GITHUB_REF#refs/heads/}}"
            git push origin HEAD:$branch_name
          fi