name: Check kcl-samples files for proper header structure

on:
  pull_request:
    paths:
      - 'public/kcl-samples/**/*.kcl'
      - .github/workflows/check-kcl-header.yml
    branches:
      - main
  push:
    paths:
      - 'public/kcl-samples/**/*.kcl'
      - .github/workflows/check-kcl-header.yml
    branches:
      - main

permissions:
  contents: read

jobs:
  check-kcl-header:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - name: Check KCL files for header comment block and blank line
        run: |
          files=$(find public/kcl-samples -type f -name '*.kcl')
          failed_files=()

          for file in $files; do
            if ! awk '
              NR == 1 && $0 !~ /^\/\// { exit 1 }
              BEGIN { in_comment = 1 }
              NF == 0 && in_comment == 1 { in_comment = 0; next }
              $1 !~ /^\/\// && in_comment == 1 { exit 1 }
              in_comment == 0 && NF > 0 { exit 0 }
              END { if (in_comment == 1) exit 1 }
              ' "$file"; then
              failed_files+=("$file")
            fi
          done

          if [ ${#failed_files[@]} -ne 0 ]; then
            echo "One or more KCL files do not begin with a header comment block followed by a blank line:"
            printf '%s\n' "${failed_files[@]}"
            exit 1
          fi