assign.yml

name: Assign on Comment

on:
  issue_comment:
    types: [created]

permissions:
  issues: write
  pull-requests: write

jobs:
  assign-on-comment:
    runs-on: ubuntu-latest
    if: github.event.issue.pull_request == null
    steps:
      - name: Assign users based on comment
        uses: actions/github-script@v7
        with:
          script: |
            const commentBody = context.payload.comment.body.trim();
            const commenter = context.payload.comment.user.login;
            const issueNumber = context.payload.issue.number;
            const repo = context.repo.repo;
            const owner = context.repo.owner;

            const isMaintainer = async (username) => {
              const { data: collaborators } = await github.rest.repos.listCollaborators({
                owner,
                repo,
                affiliation: 'direct'
              });
              return collaborators.some(user => user.login === username);
            };

            const postComment = async (body) => {
              await github.rest.issues.createComment({
                owner,
                repo,
                issue_number: issueNumber,
                body
              });
            };

            const commandMatch = commentBody.match(/^\/assign\s*(.*)?$/);
            if (!commandMatch) return;

            const mentionedUser = commandMatch[1]?.trim();
            const commenterIsMaintainer = await isMaintainer(commenter);

            if (mentionedUser) {
              if (!mentionedUser.startsWith('@')) {
                await postComment("❌ Invalid syntax. Use `/assign @username` to assign someone.");
                return;
              }

              const targetUser = mentionedUser.replace('@', '');

              if (!commenterIsMaintainer) {
                await postComment("❌ You must be a project maintainer to assign others.");
                return;
              }

              try {
                await github.rest.issues.addAssignees({
                  owner,
                  repo,
                  issue_number: issueNumber,
                  assignees: [targetUser]
                });
                await postComment(`✅ Assigned @${targetUser} as requested by maintainer @${commenter}.`);
              } catch (err) {
                await postComment(`❌ Failed to assign @${targetUser}. Maybe they don't have permission or aren't a contributor.`);
              }
            } else {
              const assignee = commenter;
              try {
                await github.rest.issues.addAssignees({
                  owner,
                  repo,
                  issue_number: issueNumber,
                  assignees: [assignee]
                });
                await postComment(`✅ Assigned @${assignee} to this issue.`);
              } catch (err) {
                await postComment(`❌ Failed to assign @${assignee}. Do you have permission or are you a contributor?`);
              }
            }