pr-reviewer.yml

name: Auto Assign Reviewers

on:
  pull_request_target:
    branches: [ 'develop', 'release_**' ]
    types: [ opened, edited, reopened ]

jobs:
  assign-reviewers:
    name: Assign Reviewers by Scope
    runs-on: ubuntu-latest
    permissions:
      contents: read
      pull-requests: write

    steps:
      - name: Assign reviewers based on PR title scope
        uses: actions/github-script@v8
        with:
          script: |
            const title = context.payload.pull_request.title;
            const prAuthor = context.payload.pull_request.user.login;

            // ── Scope → Reviewer mapping ──────────────────────────────
            const scopeReviewers = {
              'framework':  ['xxo1shine',    '317787106'],
              'chainbase':  ['halibobo1205', 'lvs0075'],
              'db':         ['halibobo1205', 'xxo1shine'],
              'trie':       ['halibobo1205', '317787106'],
              'actuator':   ['yanghang8612', 'lxcmyf'],
              'consensus':  ['lvs0075',      'xxo1shine'],
              'protocol':   ['lvs0075',      'waynercheung'],
              'common':     ['xxo1shine',    'lxcmyf'],
              'crypto':     ['Federico2014', '3for'],
              'net':        ['317787106',    'xxo1shine'],
              'vm':         ['yanghang8612', 'CodeNinjaEvan'],
              'tvm':        ['yanghang8612', 'CodeNinjaEvan'],
              'jsonrpc':    ['0xbigapple',   'bladehan1'],
              'rpc':        ['317787106',    'Sunny6889'],
              'http':       ['Sunny6889',    'bladehan1'],
              'event':      ['xxo1shine',    '0xbigapple'],
              'config':     ['317787106',    'halibobo1205'],
              'backup':     ['xxo1shine',    '317787106'],
              'lite':       ['bladehan1',    'halibobo1205'],
              'toolkit':    ['halibobo1205', 'Sunny6889'],
              'plugins':    ['halibobo1205', 'Sunny6889'],
              'docker':     ['3for',         'kuny0707'],
              'test':       ['bladehan1',    'lxcmyf'],
              'metrics':    ['halibobo1205', 'Sunny6889'],
              'api':        ['0xbigapple',   'waynercheung', 'bladehan1'],
              'ci':         ['bladehan1',    'halibobo1205'],
            };
            const defaultReviewers = ['halibobo1205', '317787106'];

            // ── Normalize helper ─────────────────────────────────────
            // Strip spaces, hyphens, underscores and lower-case so that
            // "VM", " json rpc ", "chain-base", "Json_Rpc" all normalize
            // to their canonical key form ("vm", "jsonrpc", "chainbase").
            const normalize = s => s.toLowerCase().replace(/[\s\-_]/g, '');

            // ── Extract scope from conventional commit title ──────────
            // Format: type(scope): description
            // Also supports: type(scope1,scope2): description
            const scopeMatch = title.match(/^\w+\(([^)]+)\):/);
            const rawScope = scopeMatch ? scopeMatch[1] : null;

            core.info(`PR title : ${title}`);
            core.info(`Raw scope: ${rawScope || '(none)'}`);

            // ── Skip if reviewers already assigned ──────────────────
            const pr = await github.rest.pulls.get({
              owner: context.repo.owner,
              repo: context.repo.repo,
              pull_number: context.payload.pull_request.number,
            });
            const existing = pr.data.requested_reviewers || [];
            if (existing.length > 0) {
              core.info(`Reviewers already assigned (${existing.map(r => r.login).join(', ')}). Skipping.`);
              return;
            }

            // ── Determine reviewers ───────────────────────────────────
            // 1. Split by comma to support multi-scope: feat(vm,rpc): ...
            // 2. Normalize each scope token
            // 3. Match against keys: exact match first, then contains match
            //    (longest key wins to avoid "net" matching inside "jsonrpc")
            let matched = new Set();
            let matchedScopes = [];

            if (rawScope) {
              const tokens = rawScope.split(',').map(s => normalize(s.trim()));
              // Pre-sort keys by length descending so longer keys match first
              const sortedKeys = Object.keys(scopeReviewers)
                .sort((a, b) => b.length - a.length);

              for (const token of tokens) {
                if (!token) continue;
                // Exact match
                if (scopeReviewers[token]) {
                  matchedScopes.push(token);
                  scopeReviewers[token].forEach(r => matched.add(r));
                  continue;
                }
                // Contains match: token contains a key, or key contains token
                // Prefer longest key that matches
                const found = sortedKeys.find(k => token.includes(k) || k.includes(token));
                if (found) {
                  matchedScopes.push(`${token}→${found}`);
                  scopeReviewers[found].forEach(r => matched.add(r));
                }
              }
            }

            let reviewers = matched.size > 0
              ? [...matched]
              : defaultReviewers;

            core.info(`Matched scopes: ${matchedScopes.length > 0 ? matchedScopes.join(', ') : '(none — using default)'}`);
            core.info(`Candidate reviewers: ${reviewers.join(', ')}`);

            // Exclude the PR author from the reviewer list
            reviewers = reviewers.filter(r => r.toLowerCase() !== prAuthor.toLowerCase());

            if (reviewers.length === 0) {
              core.info('No eligible reviewers after excluding PR author. Skipping.');
              return;
            }

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

            // ── Request reviews ───────────────────────────────────────
            try {
              await github.rest.pulls.requestReviewers({
                owner: context.repo.owner,
                repo: context.repo.repo,
                pull_number: context.payload.pull_request.number,
                reviewers: reviewers,
              });
              core.info('Reviewers assigned successfully.');
            } catch (error) {
              // If a reviewer is not a collaborator the API returns 422;
              // log the error but do not fail the workflow.
              core.warning(`Failed to assign some reviewers: ${error.message}`);
            }