name: Auto Assign Reviewers

on:
  pull_request:
    types: [opened, edited, review_requested]

jobs:
  assign-reviewers:
    runs-on: ubuntu-latest

    steps:
      - name: Check out the repository
        uses: actions/checkout@v4

      - name: Assign reviewers as assignees
        uses: actions/github-script@v7
        with:
          github-token: ${{ secrets.PRBOT_PAT }}
          script: |
            const { owner, repo } = context.repo;

            async function getCurrentPR() {
              if (context.payload.pull_request) {
                return context.payload.pull_request;
              }
              
              const allPRs = await github.rest.pulls.list({
                owner,
                repo,
                state: 'open',
              });
              
              return allPRs.data.find(pr => pr.head.sha === context.sha);
            }

            const pr = await getCurrentPR();
            if (!pr) {
              console.log('No matching PR found.');
              return;
            }

            console.log(`Processing PR #${pr.number}`);

            const reviewers = pr.requested_reviewers.map(reviewer => reviewer.login);

            if (reviewers.length === 0) {
              console.log('No reviewers found for this PR.');
              return;
            }

            console.log(`Current reviewers: ${reviewers.join(', ')}`);

            await github.rest.issues.addAssignees({
              owner,
              repo,
              issue_number: pr.number,
              assignees: reviewers,
            });

            console.log(`Assigned ${reviewers.join(', ')} as assignees to PR #${pr.number}`);