name: Request reviewers

on:
  pull_request_target:
    types:
      - opened
      - reopened
      - synchronize
      - ready_for_review

permissions:
  contents: read
  issues: write

jobs:
  request-reviewers:
    name: Request reviewers
    runs-on: ubuntu-latest
    steps:
      - name: Notify reviewers based on changed files
        uses: actions/github-script@v8
        with:
          script: |
            const rules = [
              { pattern: 'crates/pumpkin-protocol/', reviewers: ['Snowiiii', 'xRookieFight'] },
              { pattern: 'crates/pumpkin/src/net/', reviewers: ['Snowiiii', 'xRookieFight'] },

              { pattern: 'assets/bedrock/', reviewers: ['ZlordHUN', 'xRookieFight'] },
              { pattern: 'crates/pumpkin-protocol/src/bedrock/', reviewers: ['ZlordHUN', 'xRookieFight', 'QuantumSegfault'] },
              { pattern: 'crates/pumpkin/src/net/bedrock/', reviewers: ['ZlordHUN', 'xRookieFight', 'QuantumSegfault'] },

              { pattern: 'crates/pumpkin/src/command/', reviewers: ['aure31'] },

              { pattern: 'crates/pumpkin-plugin-api/', reviewers: ['vyPal', 'yunuservices'] },
              { pattern: 'crates/pumpkin-plugin-wit/', reviewers: ['vyPal', 'yunuservices', 'QuantumSegfault'] },
              { pattern: 'crates/pumpkin-api-macros/', reviewers: ['vyPal', 'yunuservices'] },
              { pattern: 'crates/pumpkin/src/plugin/', reviewers: ['vyPal', 'yunuservices', 'QuantumSegfault'] },

              { pattern: '*.md', reviewers: ['Q2297045667'] },
              { pattern: 'docs/', reviewers: ['Q2297045667'] },

              { pattern: 'crates/pumpkin/src/entity/mob/', reviewers: ['Snowiiii', 'RoosterBooster007'] },
              { pattern: 'crates/pumpkin/src/entity/projectile/', reviewers: ['Snowiiii', 'RoosterBooster007'] },

              { pattern: 'crates/pumpkin/src/block/', reviewers: ['Snowiiii', 'RoosterBooster007'] },
              { pattern: 'crates/pumpkin/src/item/', reviewers: ['Snowiiii', 'RoosterBooster007'] },

              { pattern: 'crates/pumpkin-world/src/generation/feature/', reviewers: ['Snowiiii', 'RoosterBooster007', 'MegalithOfficial'] },
              { pattern: 'crates/pumpkin-world/src/generation/noise/', reviewers: ['Snowiiii', 'RoosterBooster007', 'MegalithOfficial'] },
            ];

            const matches = (path, pattern) => {
              if (pattern === '*') return true;
              if (pattern.endsWith('/')) return path.startsWith(pattern);
              if (pattern.startsWith('*.')) return path.endsWith(pattern.slice(1));
              return path === pattern;
            };

            const files = await github.paginate(
              github.rest.pulls.listFiles,
              {
                owner: context.repo.owner,
                repo: context.repo.repo,
                pull_number: context.issue.number,
                per_page: 100,
              },
            );

            const reviewers = new Set();
            for (const file of files) {
              const matchingRule = [...rules].reverse().find((rule) => matches(file.filename, rule.pattern));
              matchingRule?.reviewers.forEach((reviewer) => reviewers.add(reviewer));
            }

            const author = context.payload.pull_request.user.login;
            reviewers.delete(author);

            if (reviewers.size === 0) {
              core.info('No reviewers matched the changed files.');
              return;
            }

            const mentionList = [...reviewers].sort().map((reviewer) => `@${reviewer}`);
            const marker = '<!-- pumpkin-reviewers -->';
            const body = [
              marker,
              'Review requested from:',
              '',
              mentionList.join(' '),
            ].join('\n');

            const comments = await github.paginate(
              github.rest.issues.listComments,
              {
                owner: context.repo.owner,
                repo: context.repo.repo,
                issue_number: context.issue.number,
                per_page: 100,
              },
            );
            const previousComment = comments
              .filter((comment) => comment.body?.includes(marker))
              .sort((a, b) => new Date(b.created_at) - new Date(a.created_at))[0];

            if (previousComment?.body === body) {
              core.info('Reviewer notification is already up to date.');
              return;
            }

            await github.rest.issues.createComment({
              owner: context.repo.owner,
              repo: context.repo.repo,
              issue_number: context.issue.number,
              body,
            });

            core.info(`Notified reviewers: ${mentionList.join(', ')}`);