cad-export.yml

# .github/workflows/cad-export.yml
#
# Automatically generates STEP files from FreeCAD designs when PRs are opened
# or updated. Exports are committed back to the branch in the appropriate
# STEP_FILES folder.
#
# Directory structure expected:
#   */CAD_INTERNAL/FREECAD_FILES/*.FCStd  - Source files (triggers export)
#   */CAD_INTERNAL/STEP_FILES/*.step      - Export destination
#
# Requirements:
#   - Git LFS must be configured in the repo for *.step files
#   - .gitattributes should contain: *.step filter=lfs diff=lfs merge=lfs -text

name: CAD Export

on:
  pull_request:
    branches: [main, develop]
    paths:
      - '**/CAD_INTERNAL/FREECAD_FILES/**/*.FCStd'

  workflow_dispatch:
    inputs:
      export_all:
        description: 'Export all designs (not just changed files)'
        required: false
        default: 'false'
        type: boolean

# Prevent concurrent runs on the same PR (avoids commit conflicts)
concurrency:
  group: cad-export-${{ github.head_ref || github.ref }}
  cancel-in-progress: true

jobs:
  export-step:
    name: Export STEP files
    runs-on: ubuntu-latest

    # Required for committing back to the branch
    permissions:
      contents: write
      pull-requests: write

    steps:
      - name: Checkout repository
        uses: actions/checkout@v4
        with:
          lfs: true
          fetch-depth: 0
          ref: ${{ github.head_ref }}
          token: ${{ secrets.GITHUB_TOKEN }}

      - name: Setup Git LFS
        run: |
          git lfs install
          git lfs track "*.step"
          git lfs track "*.STEP"
          echo "Git LFS configured"

      - name: Install FreeCAD
        run: |
          sudo add-apt-repository -y ppa:freecad-maintainers/freecad-stable
          sudo apt-get update
          sudo apt-get install -y freecad
          echo "FreeCAD version:"
          freecad --version || freecadcmd --version || echo "Version check not available"

      - name: Identify changed CAD files
        id: changed-files
        run: |
          if [[ "${{ github.event_name }}" == "workflow_dispatch" && "${{ inputs.export_all }}" == "true" ]]; then
            FILES=$(find . -path "*/CAD_INTERNAL/FREECAD_FILES/*.FCStd" -type f | tr '\n' ' ')
          else
            FILES=$(git diff --name-only origin/${{ github.base_ref }}...HEAD -- 'CAD_INTERNAL/FREECAD_FILES/Assemblies/**/*.FCStd' | tr '\n' ' ')
          fi

          echo "files=$FILES" >> $GITHUB_OUTPUT
          echo "Found CAD files to export: $FILES"
          
          if [ -z "$FILES" ]; then
            echo "No .FCStd files to process"
            echo "has_files=false" >> $GITHUB_OUTPUT
          else
            echo "has_files=true" >> $GITHUB_OUTPUT
          fi

      - name: Export STEP files
        if: steps.changed-files.outputs.has_files == 'true'
        run: |
          freecadcmd .github/scripts/export_step.py ${{ steps.changed-files.outputs.files }}

      - name: Generate export summary
        if: steps.changed-files.outputs.has_files == 'true'
        run: |
          echo "## 📦 STEP Export Summary" > export_summary.md
          echo "" >> export_summary.md
          echo "| Source File | Export | Size |" >> export_summary.md
          echo "|-------------|--------|------|" >> export_summary.md

          for step_file in $(find . -path "*/CAD_INTERNAL/STEP_FILES/*.step" -type f 2>/dev/null); do
            if [ -f "$step_file" ]; then
              filename=$(basename "$step_file")
              source_name="${filename%.step}.FCStd"
              size=$(du -h "$step_file" | cut -f1)
              relative_path="${step_file#./}"
              echo "| \`$source_name\` | \`$relative_path\` | $size |" >> export_summary.md
            fi
          done

          echo "" >> export_summary.md
          echo "_Generated by GitHub Actions on $(date -u '+%Y-%m-%d %H:%M UTC')_" >> export_summary.md

          cat export_summary.md

      - name: Commit STEP files
        if: steps.changed-files.outputs.has_files == 'true'
        run: |
          git config user.name "github-actions[bot]"
          git config user.email "github-actions[bot]@users.noreply.github.com"

          git add .gitattributes 2>/dev/null || true
          find . -path "*/CAD_INTERNAL/STEP_FILES/*.step" -type f -exec git add {} \;

          if git diff --staged --quiet; then
            echo "No STEP file changes to commit"
          else
            git commit -m "Auto-generate STEP exports [skip ci]"
            git push
            echo "Committed and pushed STEP exports"
          fi

      - name: Collect STEP files for artefact
        if: steps.changed-files.outputs.has_files == 'true'
        run: |
          mkdir -p step_artefacts
          find . -path "*/CAD_INTERNAL/STEP_FILES/*.step" -exec cp {} step_artefacts/ \; 2>/dev/null || true
          ls -la step_artefacts/ || echo "No files collected"

      - name: Upload STEP artefacts
        if: steps.changed-files.outputs.has_files == 'true'
        uses: actions/upload-artifact@v4
        with:
          name: step-exports
          path: step_artefacts/
          if-no-files-found: ignore
          retention-days: 30

      - name: Comment on PR
        if: github.event_name == 'pull_request' && steps.changed-files.outputs.has_files == 'true'
        uses: actions/github-script@v7
        with:
          script: |
            const fs = require('fs');
            let summary = '';
            try {
              summary = fs.readFileSync('export_summary.md', 'utf8');
            } catch (e) {
              summary = '## 📦 STEP Export\n\nSTEP files have been exported and committed to this branch.';
            }

            github.rest.issues.createComment({
              issue_number: context.issue.number,
              owner: context.repo.owner,
              repo: context.repo.repo,
              body: summary
            });

      - name: No files to export
        if: steps.changed-files.outputs.has_files != 'true'
        run: |
          echo "No FreeCAD files found that require export."
          echo "This workflow runs when .FCStd files in CAD_INTERNAL/FREECAD_FILES/ are changed."