visualize_stopping_patterns_comment.yml

name: Post stopping pattern visualization comment

on:
  workflow_run:
    workflows: ["Visualize Stopping Patterns"]
    types: [completed]

permissions:
  actions: read
  pull-requests: write
  issues: write

jobs:
  comment:
    name: Post visualization comment
    runs-on: ubuntu-latest
    if: >-
      github.event.workflow_run.conclusion == 'success' &&
      github.event.workflow_run.event == 'pull_request'
    steps:
      - name: Download artifacts
        uses: actions/download-artifact@v4
        with:
          name: visualization-result
          path: /tmp/visualize-artifacts
          run-id: ${{ github.event.workflow_run.id }}
          github-token: ${{ github.token }}

      - name: Read metadata
        id: meta
        run: |
          PR_NUMBER="${{ github.event.workflow_run.pull_requests[0].number }}"
          if [ -z "$PR_NUMBER" ] && [ -s /tmp/visualize-artifacts/pr_number ]; then
            PR_NUMBER=$(cat /tmp/visualize-artifacts/pr_number)
            echo "::warning::pull_requests context empty, using artifact fallback"
          fi
          if [ -z "$PR_NUMBER" ]; then
            echo "::error::Could not determine PR number"
            exit 1
          fi
          echo "pr_number=$PR_NUMBER" >> "$GITHUB_OUTPUT"

          if [ -s /tmp/visualize-artifacts/has_changes ]; then
            echo "has_changes=$(cat /tmp/visualize-artifacts/has_changes)" >> "$GITHUB_OUTPUT"
          else
            echo "::warning::has_changes metadata missing or empty, defaulting to false"
            echo "has_changes=false" >> "$GITHUB_OUTPUT"
          fi

      - name: Find existing comment
        uses: peter-evans/find-comment@v3
        id: find_comment
        with:
          issue-number: ${{ steps.meta.outputs.pr_number }}
          comment-author: "github-actions[bot]"
          body-includes: "<!-- station-visualizer -->"

      - name: Post or update comment
        if: steps.meta.outputs.has_changes == 'true'
        uses: peter-evans/create-or-update-comment@v4
        with:
          issue-number: ${{ steps.meta.outputs.pr_number }}
          comment-id: ${{ steps.find_comment.outputs.comment-id }}
          body-path: /tmp/visualize-artifacts/visualization_comment.md
          edit-mode: replace

      - name: Delete comment if no changes
        if: steps.meta.outputs.has_changes == 'false' && steps.find_comment.outputs.comment-id != ''
        run: gh api repos/${{ github.repository }}/issues/comments/${{ steps.find_comment.outputs.comment-id }} -X DELETE
        env:
          GH_TOKEN: ${{ github.token }}