name: PR Label Bot

on:
  pull_request_target:
    types:
      - opened
      - reopened
  issue_comment:
    types:
      - created

permissions:
  contents: read
  pull-requests: write
  issues: write

jobs:
  request-label:
    if: github.event_name == 'pull_request_target' && github.event.pull_request.author_association != 'COLLABORATOR' && github.event.pull_request.author_association != 'OWNER' && github.event.pull_request.author_association != 'MEMBER'
    permissions:
      contents: read
      pull-requests: write
      issues: write
    runs-on: ubuntu-latest
    steps:
      - name: Ask PR author for label
        uses: actions/github-script@v9
        with:
          script: |
            function isPermissionDenied(error) {
              return error && error.status === 403 && /Resource not accessible by integration/i.test(error.message || '');
            }

            const allowedLabels = [
              'bug-fix',
              'enhancement',
              'Localization',
              'profile',
              'QoL',
              'UI/UX',
              'dependencies'
            ];
            const pr = context.payload.pull_request;
            const labelsList = `${allowedLabels
              .slice(0, -1)
              .map((label) => `\`${label}\``)
              .join(', ')} and \`${allowedLabels[allowedLabels.length - 1]}\`.`;
            const examplesText = [
              '```',
              '/bot add-label bug-fix',
              '```',
              '```',
              '/bot add-label bug-fix, UI/UX',
              '```',
              '```',
              '/bot remove-label bug-fix, UI/UX',
              '```'
            ].join('\n');

            try {
              await github.rest.issues.createComment({
                owner: context.repo.owner,
                repo: context.repo.repo,
                issue_number: pr.number,
                body:
                  `Hi @${pr.user.login}, you can manage the labels for this PR by \`/bot add-label\` and \`/bot remove-label\`\n\n` +
                  `Allowed labels are:\n${labelsList}\n\n` +
                  `Examples:\n${examplesText}`
              });
            } catch (error) {
              if (isPermissionDenied(error)) {
                core.warning(
                  'Skipping PR comment because token cannot write. Enable Actions write permissions, ' +
                  'or run with a token that has issues:write and pull_requests:write.'
                );
                return;
              }

              throw error;
            }

  apply-label:
    if: github.event_name == 'issue_comment'
    permissions:
      contents: read
      pull-requests: write
      issues: write
    runs-on: ubuntu-latest
    steps:
      - name: Apply label command from PR author
        uses: actions/github-script@v9
        with:
          script: |
            function isPermissionDenied(error) {
              return error && error.status === 403 && /Resource not accessible by integration/i.test(error.message || '');
            }

            const allowedLabels = [
              'bug-fix',
              'enhancement',
              'Localization',
              'profile',
              'QoL',
              'UI/UX',
              'dependencies'
            ];

            const issue = context.payload.issue;
            if (!issue.pull_request) {
              core.info('Ignoring comment that is not on a pull request.');
              return;
            }

            const body = (context.payload.comment.body || '').trim();
            const commandLine = body
              .split('\n')
              .map((line) => line.trim())
              .find((line) => /^\/bot\s+(add-label|remove-label)(?:\s*:\s*|\s+)/i.test(line));

            if (!commandLine) {
              core.info('No /bot add-label or /bot remove-label command found.');
              return;
            }

            const commandMatch = commandLine.match(/^\/bot\s+(add-label|remove-label)(?:\s*:\s*|\s+)(.+)\s*$/i);
            if (!commandMatch) {
              core.info('Label command format is invalid.');
              return;
            }

            const action = commandMatch[1].toLowerCase() === 'add-label' ? 'add' : 'remove';
            let labelsExpr = (commandMatch[2] || '').trim();
            if (!labelsExpr) {
              core.info('Label command is missing label name.');
              return;
            }

            if (labelsExpr.startsWith('[') && labelsExpr.endsWith(']')) {
              labelsExpr = labelsExpr.slice(1, -1).trim();
            }

            const requestedRawLabels = labelsExpr
              .split(',')
              .map((part) => part.trim())
              .filter(Boolean);

            if (!requestedRawLabels.length) {
              core.info('No labels were provided in the command.');
              return;
            }

            const { data: pr } = await github.rest.pulls.get({
              owner: context.repo.owner,
              repo: context.repo.repo,
              pull_number: issue.number
            });

            const commenter = context.payload.comment.user.login;
            if (commenter !== pr.user.login) {
              core.info('Ignoring command because commenter is not the PR author.');
              return;
            }

            const labelsByLower = new Map(
              allowedLabels.map((label) => [label.toLowerCase(), label])
            );

            const resolvedLabels = [];
            const invalidLabels = [];

            for (const rawLabel of requestedRawLabels) {
              const resolved = labelsByLower.get(rawLabel.toLowerCase());
              if (resolved) {
                resolvedLabels.push(resolved);
              } else {
                invalidLabels.push(rawLabel);
              }
            }
            const uniqueRequestedLabels = [...new Set(resolvedLabels)];

            if (action === 'add' && uniqueRequestedLabels.length) {
              try {
                await github.rest.issues.addLabels({
                  owner: context.repo.owner,
                  repo: context.repo.repo,
                  issue_number: issue.number,
                  labels: uniqueRequestedLabels
                });
              } catch (error) {
                if (isPermissionDenied(error)) {
                  core.warning(
                    'Cannot add labels because token cannot write. Enable Actions write permissions, ' +
                    'or run with a token that has issues:write and pull_requests:write.'
                  );
                  return;
                }

                throw error;
              }

              core.info(`Added labels: ${uniqueRequestedLabels.join(', ')}`);
            }

            if (action === 'remove' && uniqueRequestedLabels.length) {
              let removedCount = 0;
              try {
                for (const label of uniqueRequestedLabels) {
                  try {
                    await github.rest.issues.removeLabel({
                      owner: context.repo.owner,
                      repo: context.repo.repo,
                      issue_number: issue.number,
                      name: label
                    });
                    removedCount += 1;
                  } catch (error) {
                    if (isPermissionDenied(error)) {
                      core.warning(
                        'Cannot remove labels because token cannot write. Enable Actions write permissions, ' +
                        'or run with a token that has issues:write and pull_requests:write.'
                      );
                      return;
                    }

                    if (error.status === 404) {
                      core.info(`Label is not currently applied: ${label}`);
                      continue;
                    }

                    throw error;
                  }
                }

                core.info(`Removed labels count: ${removedCount}`);
              } catch (error) {
                throw error;
              }
            }

            if (!uniqueRequestedLabels.length) {
              core.info('No valid labels were provided in the command.');
            }

            if (invalidLabels.length) {
              const allowedText = allowedLabels.map((label) => `\`${label}\``).join(', ');
              const invalidText = invalidLabels.map((label) => `\`${label}\``).join(', ');
              const validText = uniqueRequestedLabels.length
                ? `\n\nProcessed valid label(s): ${uniqueRequestedLabels.map((label) => `\`${label}\``).join(', ')}`
                : '';

              try {
                await github.rest.issues.createComment({
                  owner: context.repo.owner,
                  repo: context.repo.repo,
                  issue_number: issue.number,
                  body:
                    `@${commenter} invalid label(s): ${invalidText}.${validText}\n\n` +
                    `Allowed labels: ${allowedText}\n\n` +
                    `Use:\n` +
                    `- \`/bot add-label label\`\n` +
                    `- \`/bot remove-label label\`\n` +
                    `- \`/bot add-label label1, label2\``
                });
              } catch (error) {
                if (isPermissionDenied(error)) {
                  core.warning('Cannot post invalid-label feedback because token cannot write comments.');
                  return;
                }

                throw error;
              }
            }

            const processedLabelsText = uniqueRequestedLabels.length ? uniqueRequestedLabels.join(', ') : '(none)';
            core.info(`Processed label command: ${action} ${processedLabelsText}`);