name: DCO

# Verifies Developer Certificate of Origin sign-off.
# On push to main: passes (squash merges via admin are signed).
# On PR: verifies Signed-off-by trailers on commits.

on:
  push:
    branches: [main]
  pull_request:
    types: [opened, synchronize, reopened]
  workflow_dispatch:

permissions:
  contents: read
  pull-requests: read

jobs:
  dco:
    name: DCO sign-off check
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
        with:
          fetch-depth: 0
      - name: Check DCO on PR commits
        if: github.event_name == 'pull_request'
        env:
          GH_TOKEN: ${{ github.token }}
        run: |
          echo "Checking Signed-off-by on PR commits..."
          # Get commits in this PR
          COMMITS=$(gh api "repos/${{ github.repository }}/pulls/${{ github.event.pull_request.number }}/commits" --jq '.[].sha' 2>/dev/null || echo "")
          if [ -z "$COMMITS" ]; then
            echo "No commits found — assuming OK"
            exit 0
          fi
          FAIL=0
          for sha in $COMMITS; do
            body=$(git log -1 --format="%B" "$sha" 2>/dev/null || echo "")
            if echo "$body" | grep -q "^Signed-off-by:"; then
              echo "  OK: $sha"
            else
              echo "  MISSING: $sha — no Signed-off-by"
              FAIL=1
            fi
          done
          exit $FAIL
      - name: DCO status (push/workflow_dispatch)
        if: github.event_name != 'pull_request'
        run: |
          echo "Push to main — commits signed via PR DCO gate or admin squash merge."
          echo "DCO OK"