sync-upstream.yml

name: Sync Upstream

# Runs weekly on Sunday at midnight UTC, or manually
on:
  schedule:
    - cron: '0 0 * * *'  # Daily at 00:00 UTC
  workflow_dispatch:      # Allow manual trigger

jobs:
  sync-main:
    name: Sync main with upstream
    runs-on: ubuntu-latest
    permissions:
      contents: write
      pull-requests: write

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

      - name: Configure Git
        run: |
          git config user.name "github-actions[bot]"
          git config user.email "github-actions[bot]@users.noreply.github.com"

      - name: Add upstream remote
        run: git remote add upstream https://github.com/typst/typst.git

      - name: Fetch upstream
        run: git fetch upstream

      - name: Check for upstream changes
        id: check-changes
        run: |
          BEHIND=$(git rev-list --count HEAD..upstream/main)
          echo "commits_behind=$BEHIND" >> $GITHUB_OUTPUT
          if [ "$BEHIND" -gt 0 ]; then
            echo "has_changes=true" >> $GITHUB_OUTPUT
            echo "Found $BEHIND new commits from upstream"
          else
            echo "has_changes=false" >> $GITHUB_OUTPUT
            echo "Already up to date with upstream"
          fi

      - name: Merge upstream into main
        if: steps.check-changes.outputs.has_changes == 'true'
        run: |
          git checkout main
          git merge upstream/main --no-edit
          git push origin main

      - name: Check feature branch for conflicts
        if: steps.check-changes.outputs.has_changes == 'true'
        id: check-feature
        run: |
          git checkout feature/text-flow

          # Try a test merge to detect conflicts
          if git merge main --no-commit --no-ff 2>/dev/null; then
            echo "conflict=false" >> $GITHUB_OUTPUT
            git merge --abort 2>/dev/null || true
          else
            echo "conflict=true" >> $GITHUB_OUTPUT
            git merge --abort 2>/dev/null || true
          fi

      - name: Create PR for feature branch update (no conflicts)
        if: steps.check-changes.outputs.has_changes == 'true' && steps.check-feature.outputs.conflict == 'false'
        env:
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        run: |
          # Create a temporary branch with the merge
          git checkout feature/text-flow
          BRANCH_NAME="sync/feature-text-flow-$(date +%Y%m%d)"
          git checkout -b "$BRANCH_NAME"
          git merge main --no-edit
          git push origin "$BRANCH_NAME"

          # Create PR
          gh pr create \
            --base feature/text-flow \
            --head "$BRANCH_NAME" \
            --title "Sync feature/text-flow with upstream ($(date +%Y-%m-%d))" \
            --body "$(cat <<'EOF'
          ## Automated Upstream Sync

          This PR merges the latest upstream changes into the feature/text-flow branch.

          **Commits from upstream:** ${{ steps.check-changes.outputs.commits_behind }}

          ### Review Checklist
          - [ ] Tests pass
          - [ ] No regressions in text-flow feature
          - [ ] Build succeeds

          ---
          *This PR was automatically created by the sync-upstream workflow.*
          EOF
          )"

      - name: Create issue for conflicts
        if: steps.check-changes.outputs.has_changes == 'true' && steps.check-feature.outputs.conflict == 'true'
        env:
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        run: |
          # Get list of conflicting files
          git checkout feature/text-flow
          CONFLICTS=$(git merge main --no-commit 2>&1 | grep "CONFLICT" || echo "Unable to determine specific conflicts")
          git merge --abort 2>/dev/null || true

          gh issue create \
            --title "Manual merge required: upstream sync conflicts ($(date +%Y-%m-%d))" \
            --body "$(cat <<EOF
          ## Upstream Sync Conflict

          The automated sync found **${{ steps.check-changes.outputs.commits_behind }}** new commits from upstream, but there are merge conflicts with the \`feature/text-flow\` branch.

          ### Conflicts Detected
          \`\`\`
          $CONFLICTS
          \`\`\`

          ### Manual Resolution Steps

          \`\`\`bash
          cd /Users/jrhayward/repositories/typst-fork
          git fetch origin
          git fetch upstream

          # Update main first
          git checkout main
          git pull origin main

          # Now merge into feature branch
          git checkout feature/text-flow
          git merge main

          # Resolve conflicts, then:
          git add .
          git commit
          git push origin feature/text-flow
          \`\`\`

          ---
          *This issue was automatically created by the sync-upstream workflow.*
          EOF
          )"

  notify-summary:
    name: Summary
    runs-on: ubuntu-latest
    needs: sync-main
    if: always()
    steps:
      - name: Workflow summary
        run: |
          echo "## Upstream Sync Complete" >> $GITHUB_STEP_SUMMARY
          echo "" >> $GITHUB_STEP_SUMMARY
          echo "Check the Actions tab for details." >> $GITHUB_STEP_SUMMARY