name: issue-format

on:
  issues:
    types: [opened, edited]

permissions:
  issues: write

jobs:
  validate:
    runs-on: ubuntu-latest
    # Skip issues opened by bots (e.g. dependabot) and maintainers fixing format
    if: >-
      github.event.issue.user.type != 'Bot' &&
      !contains(github.event.issue.labels.*.name, 'format-exempt')
    steps:
      - name: Validate title and body
        uses: actions/github-script@v7
        with:
          script: |
            const issue = context.payload.issue;
            const title = issue.title.trim();
            const body = (issue.body || '').trim();
            const errors = [];

            const modernTitle = /^\[(Bug|Feature)\] .{8,}/.test(title);
            const legacyAppTitle = /^Bug:\s*.{5,}/i.test(title);
            if (!modernTitle && !legacyAppTitle) {
              errors.push(
                'Title must start with `[Bug]` or `[Feature]` followed by a short summary (at least 8 characters after the prefix). Legacy app links using `Bug: ...` are also accepted. Example: `[Bug] SFTP upload fails on Windows`'
              );
            }

            if (body.length < 120) {
              errors.push(
                'Body is too short. Please use the Bug Report or Feature Request template and fill in all required fields.'
              );
            }

            const templateMarkers = [
              'Steps to reproduce',
              'Expected behavior',
              'Actual behavior',
              'Describe the problem',
              'Problem / pain point',
              'Proposed solution',
              'Operating system',
            ];
            const hasTemplateStructure = templateMarkers.some((marker) =>
              body.includes(marker)
            );
            if (!hasTemplateStructure) {
              errors.push(
                'Body does not look like it came from an issue template. Choose **Bug Report** or **Feature Request** when opening an issue.'
              );
            }

            const labels = new Set(
              (issue.labels || []).map((label) =>
                typeof label === 'string' ? label : label.name
              )
            );

            if (errors.length === 0) {
              if (
                issue.state === 'closed' &&
                labels.has('invalid-format')
              ) {
                labels.delete('invalid-format');
                await github.rest.issues.update({
                  owner: context.repo.owner,
                  repo: context.repo.repo,
                  issue_number: issue.number,
                  state: 'open',
                  labels: [...labels],
                });
                await github.rest.issues.createComment({
                  owner: context.repo.owner,
                  repo: context.repo.repo,
                  issue_number: issue.number,
                  body: '<!-- issue-format-bot --> Format looks good now. Reopening this issue.',
                });
              }
              core.info('Issue format OK');
              return;
            }

            const issueNumber = issue.number;
            const marker = '<!-- issue-format-bot -->';
            const bodyText = [
              marker,
              '## Issue format check failed',
              '',
              'This issue was closed automatically because it does not follow the required format.',
              '',
              ...errors.map((e) => `- ${e}`),
              '',
              '### How to resubmit',
              '',
              '1. Go to [New Issue](https://github.com/binaricat/Netcatty/issues/new/choose)',
              '2. Pick **Bug Report** or **Feature Request**',
              '3. Fill in every required field',
              '4. Keep the `[Bug]` or `[Feature]` prefix in the title and add a clear summary after it (older app versions may use `Bug: ...`)',
              '',
              'For questions and open-ended discussion, use [GitHub Discussions](https://github.com/binaricat/Netcatty/discussions) instead.',
              '',
              'If you believe this was a mistake, reply here after fixing the title/body and a maintainer can reopen.',
            ].join('\n');

            const { data: comments } = await github.rest.issues.listComments({
              owner: context.repo.owner,
              repo: context.repo.repo,
              issue_number: issueNumber,
              per_page: 100,
            });
            const alreadyNotified = comments.some((c) =>
              (c.body || '').includes(marker)
            );

            if (!alreadyNotified) {
              await github.rest.issues.createComment({
                owner: context.repo.owner,
                repo: context.repo.repo,
                issue_number: issueNumber,
                body: bodyText,
              });
            }

            labels.add('invalid-format');

            await github.rest.issues.update({
              owner: context.repo.owner,
              repo: context.repo.repo,
              issue_number: issueNumber,
              state: 'closed',
              state_reason: 'not_planned',
              labels: [...labels],
            });