# Uses `workflow_run` to securely add a comment to the PR that triggered CI.
#
# Important: For security, the `workflow_run` trigger runs the workflow from the default branch,
# so any changes to this workflow must be made in the default branch to take effect.
#
# This workflow is neccesary because PRs opened by external forks do not have write access to
# their PR, so the PR-triggered workflow can't add comments to the PR.
# If this was in the CI workflow, it'd be tidier and easier to debug but unfortunately that
# isn't possible due to the lower security context that the CI workflow runs in.
name: CI comment

on:
  workflow_run:
    workflows: ["CI"]
    types:
      - completed

jobs:
  summary:
    if: github.event.workflow_run.event == 'pull_request'
    runs-on: ubuntu-latest

    steps:
      - name: Download summaries
        id: download
        uses: actions/download-artifact@v4
        with:
          run-id: ${{ github.event.workflow_run.id }}
          pattern: summary-*
          path: summaries
          github-token: ${{ secrets.GITHUB_TOKEN }}

      - name: Merge summaries
        id: summary
        run: |
          ls -R

          files=$(find $dir -type f)
          if [ -z "$files" ]; then
            echo "No files found in dir: $dir"
            exit 0
          fi

          echo "message<<EOF" >> $GITHUB_OUTPUT
          echo "## CI Summary" >> $GITHUB_OUTPUT

          for file in $files; do
            echo $(cat $file) >> $GITHUB_OUTPUT
          done

          repo_url="${{ github.server_url }}/${{ github.repository }}"
          run_url="$repo_url/actions/runs/${{ github.event.workflow_run.id }}"

          echo > $GITHUB_OUTPUT
          echo "[Full summary]($run_url) (scroll down)" >> $GITHUB_OUTPUT
          echo "EOF" >> $GITHUB_OUTPUT

      - name: Set PR comment
        if: steps.summary.outputs.message
        uses: marocchino/sticky-pull-request-comment@v2
        with:
          number: ${{ github.event.workflow_run.pull_requests[0].number }}
          header: ${{ github.event.workflow_run.name }}
          message: ${{ steps.summary.outputs.message }}

      - name: Delete PR comment
        if: ${{ !steps.summary.outputs.message }}
        uses: marocchino/sticky-pull-request-comment@v2
        with:
          number: ${{ github.event.workflow_run.pull_requests[0].number }}
          header: ${{ github.event.workflow_run.name }}
          delete: true