name: Lock down obvious spam issues

on:
  issues:
    types: [opened]

permissions:
  issues: write

jobs:
  lockdown:
    runs-on: ubuntu-latest
    steps:
      - name: Auto-close spam patterns from new accounts
        uses: actions/github-script@v7
        with:
          script: |
            const issue = context.payload.issue;
            const author = issue.user;

            // Only consider brand-new accounts. If the user has been around
            // long enough to file good-faith issues elsewhere, don't touch.
            const created = new Date(author.created_at || 0);
            const ageDays = (Date.now() - created.getTime()) / 86_400_000;
            if (ageDays > 30) return;

            const blob = `${issue.title || ''}\n${issue.body || ''}`;
            const patterns = [
              /\bcrypto\b/i,
              /\bairdrop\b/i,
              /\bnft\b/i,
              /\bpresale\b/i,
              /\busdt\b/i,
              /\btg\s*@/i,
              /\btelegram\s+@/i,
              /\bt\.me\//i,
              /\bwhatsapp\s+\+/i,
              /\bseo\s+service/i,
              /\bguest\s+post/i,
              /\bbacklink/i,
              /\bbuy\s+followers/i,
              /\bjoin\s+our\s+(community|server|group)/i,
              /\bpromot[ei]\s+your\b/i,
            ];
            const hit = patterns.find(p => p.test(blob));
            if (!hit) return;

            await github.rest.issues.createComment({
              owner: context.repo.owner,
              repo: context.repo.repo,
              issue_number: issue.number,
              body: [
                'This issue was auto-closed because the title or body matches',
                'a spam pattern (paid promotion / unrelated link) and the author',
                'account is less than 30 days old. If this is a real bug or',
                'feature request, please reopen with a clearer description',
                '(in English or 中文) of the project-relevant context.',
              ].join(' '),
            });

            await github.rest.issues.update({
              owner: context.repo.owner,
              repo: context.repo.repo,
              issue_number: issue.number,
              state: 'closed',
              state_reason: 'not_planned',
            });

            await github.rest.issues.addLabels({
              owner: context.repo.owner,
              repo: context.repo.repo,
              issue_number: issue.number,
              labels: ['spam'],
            }).catch(() => {});  // ignore if label doesn't exist yet