detect-forked-sim.yml

name: Detect Simulation Upload (Fork PR)

on:
  pull_request:
    types: [opened, synchronize]
    paths:
      - 'simulations/**.py'

jobs:
  detect:
    runs-on: ubuntu-latest
    
    steps:
      
      - name: Confirm simulation file exists
        run: echo "Detected simulation Python file in forked PR."

      - name: Checkout PR
        uses: actions/checkout@v4
        with:
          fetch-depth: 2

      - name: Validate simulation file paths
        id: validate
        run: |
          USERNAME="${{ github.event.pull_request.user.login }}"
          BASE="${{ github.event.pull_request.base.sha }}"
          HEAD="${{ github.event.pull_request.head.sha }}"

          echo "Fetching base SHA $BASE..."
          git fetch origin $BASE --depth=1

          echo "Diffing $BASE...$HEAD: looking for files submitted by the fork PR"
          FILES=$(git diff --diff-filter=AM --name-only $BASE $HEAD -- 'simulations/**/*.py' || true)
          echo "$FILES" | tee all_py_files.txt

          MATCHED_FILES=()
          INVALID_FILES=()
          while IFS= read -r file; do
            if [[ "$file" =~ ^simulations/$USERNAME/[^/]+\.py$ ]]; then
              MATCHED_FILES+=("$file")
            else
              INVALID_FILES+=("$file")
            fi
          done < all_py_files.txt

          if [ ${#INVALID_FILES[@]} -gt 0 ]; then
            echo "❌ Invalid file paths:"
            for f in "${INVALID_FILES[@]}"; do echo "  - $f"; done
            exit 1
          fi

          printf "%s\n" "${MATCHED_FILES[@]}" > matched_files.txt

      - name: Upload artifact
        uses: actions/upload-artifact@v4
        with:
          name: matched-files
          path: matched_files.txt