Synvael/.github/workflows/cla.yml

name: CLA Check

on:
  pull_request_target:
    types: [opened, reopened, synchronize]
  issue_comment:
    types: [created]

permissions:
  contents: write
  pull-requests: write
  statuses: write

jobs:
  cla-check:
    # Run on PR events, or on issue comments that are on PRs (not plain issues).
    if: >
      github.event_name == 'pull_request_target' ||
      (github.event_name == 'issue_comment' && github.event.issue.pull_request)      
    runs-on: ubuntu-latest
    steps:
      - name: Checkout repository
        uses: actions/checkout@v4
        with:
          # pull_request_target runs on the base branch; check out the base
          # so the signatures file is from the canonical source.
          ref: ${{ github.event.pull_request.base.ref || github.event.repository.default_branch }}
          token: ${{ secrets.GITHUB_TOKEN }}

      - name: CLA enforcement
        uses: actions/github-script@v7
        with:
          github-token: ${{ secrets.GITHUB_TOKEN }}
          script: |
            const fs = require('fs');
            const path = require('path');

            const SIGNATURES_FILE = '.github/cla-signatures.json';
            const CLA_AGREE_PATTERN = /I have read the CLA and I agree/i;
            const CLA_LINK = 'https://github.com/${{ github.repository }}/blob/dev/CLA.md';
            const CHECK_NAME = 'CLA Signed';

            // --- Helpers ---

            function loadSignatures() {
              try {
                const raw = fs.readFileSync(SIGNATURES_FILE, 'utf8');
                return JSON.parse(raw);
              } catch {
                return { signatures: [] };
              }
            }

            function saveSignatures(data) {
              fs.writeFileSync(SIGNATURES_FILE, JSON.stringify(data, null, 2) + '\n');
            }

            function hasSigned(data, username) {
              return data.signatures.some(
                (s) => s.github_username.toLowerCase() === username.toLowerCase()
              );
            }

            async function getAuthors(prNumber) {
              const commits = await github.paginate(
                github.rest.pulls.listCommits,
                { owner: context.repo.owner, repo: context.repo.repo, pull_number: prNumber }
              );
              const authors = new Set();
              for (const c of commits) {
                if (c.author && c.author.login) {
                  authors.add(c.author.login);
                }
              }
              return [...authors];
            }

            async function setStatus(sha, state, description) {
              await github.rest.repos.createCommitStatus({
                owner: context.repo.owner,
                repo: context.repo.repo,
                sha,
                state,
                description,
                context: CHECK_NAME,
              });
            }

            async function commitSignatures(username) {
              // Stage, commit, and push the updated signatures file using
              // the GitHub API (create-or-update-file-contents).
              const content = fs.readFileSync(SIGNATURES_FILE, 'utf8');
              const encoded = Buffer.from(content).toString('base64');

              let sha;
              try {
                const existing = await github.rest.repos.getContent({
                  owner: context.repo.owner,
                  repo: context.repo.repo,
                  path: SIGNATURES_FILE,
                  ref: context.payload.repository.default_branch,
                });
                sha = existing.data.sha;
              } catch {
                // File does not exist yet; will be created.
              }

              await github.rest.repos.createOrUpdateFileContents({
                owner: context.repo.owner,
                repo: context.repo.repo,
                path: SIGNATURES_FILE,
                message: `chore(workspace): record CLA signature for @${username}`,
                content: encoded,
                sha,
                branch: context.payload.repository.default_branch,
              });
            }

            // --- Main logic ---

            let prNumber;
            let headSha;

            if (context.eventName === 'pull_request_target') {
              prNumber = context.payload.pull_request.number;
              headSha = context.payload.pull_request.head.sha;
            } else {
              // issue_comment on a PR
              prNumber = context.payload.issue.number;
              // Fetch the PR to get the head SHA.
              const pr = await github.rest.pulls.get({
                owner: context.repo.owner,
                repo: context.repo.repo,
                pull_number: prNumber,
              });
              headSha = pr.data.head.sha;
            }

            const sigData = loadSignatures();
            const authors = await getAuthors(prNumber);

            // If this is a comment event, check if the commenter is signing.
            if (context.eventName === 'issue_comment') {
              const comment = context.payload.comment.body;
              const commenter = context.payload.comment.user.login;

              if (CLA_AGREE_PATTERN.test(comment) && authors.includes(commenter)) {
                if (!hasSigned(sigData, commenter)) {
                  sigData.signatures.push({
                    github_username: commenter,
                    signed_at: new Date().toISOString(),
                    pull_request: `https://github.com/${context.repo.owner}/${context.repo.repo}/pull/${prNumber}`,
                  });
                  saveSignatures(sigData);
                  await commitSignatures(commenter);

                  await github.rest.issues.createComment({
                    owner: context.repo.owner,
                    repo: context.repo.repo,
                    issue_number: prNumber,
                    body: `✅ @${commenter} — CLA signature recorded. Thank you!`,
                  });
                }
              }
            }

            // Re-read signatures (may have been updated above).
            const currentSigs = loadSignatures();
            const unsigned = authors.filter((a) => !hasSigned(currentSigs, a));

            if (unsigned.length === 0) {
              await setStatus(headSha, 'success', 'All authors have signed the CLA.');
              core.info('All PR authors have signed the CLA.');
            } else {
              await setStatus(headSha, 'pending', `CLA not signed by: ${unsigned.join(', ')}`);

              // Only post the instructions comment on PR open/reopen, not on
              // every push or unrelated comment.
              if (
                context.eventName === 'pull_request_target' &&
                ['opened', 'reopened'].includes(context.payload.action)
              ) {
                const mention = unsigned.map((u) => `@${u}`).join(', ');
                await github.rest.issues.createComment({
                  owner: context.repo.owner,
                  repo: context.repo.repo,
                  issue_number: prNumber,
                  body: [
                    `### 📝 CLA Signature Required`,
                    '',
                    `${mention} — thank you for your contribution! Before this pull request can be reviewed and merged, all commit authors must sign the [Contributor License Agreement](${CLA_LINK}).`,
                    '',
                    'To sign, please leave a comment on this pull request containing **exactly**:',
                    '',
                    '```',
                    'I have read the CLA and I agree',
                    '```',
                    '',
                    'Signing is a one-time action. Once recorded, all future pull requests from the same account are accepted automatically.',
                  ].join('\n'),
                });
              }

              core.info(`Unsigned authors: ${unsigned.join(', ')}`);
            }