#  Copyright 2026 Collate
#  Licensed under the Apache License, Version 2.0 (the "License");
#  you may not use this file except in compliance with the License.
#  You may obtain a copy of the License at
#  http://www.apache.org/licenses/LICENSE-2.0
#  Unless required by applicable law or agreed to in writing, software
#  distributed under the License is distributed on an "AS IS" BASIS,
#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
#  See the License for the specific language governing permissions and
#  limitations under the License.

name: PR Metadata Validation

# Fails the PR check unless it links a GitHub issue that (a) has a real
# description and (b) is tracked in the "Shipping" project with the Status,
# Source, Priority, Domain and Release fields set.
#
# Linked issues are resolved from two sources:
#   * Same-repo: GitHub's native `closingIssuesReferences` (the PR "Development"
#     section + same-repo closing keywords). This is authoritative and also
#     catches issues linked via the sidebar without a body keyword.
#   * Cross-repo (same org only): parsed from the PR body, because GitHub cannot
#     represent a cross-repo link in `closingIssuesReferences`. This path is
#     restricted to trusted authors and an explicit repo allowlist so the
#     privileged PROJECTS_TOKEN is never pointed at attacker-chosen repositories
#     under pull_request_target, and the public PR comment never echoes private
#     issue content (only numbers and field names).
#
# Projects v2 data is only available via GraphQL and the default GITHUB_TOKEN
# cannot read org-level projects (nor private same-org repos), so a PROJECTS_TOKEN
# secret (a PAT or GitHub App token with `read:project` and read access to the
# allowlisted repos) is required. Only PR / issue / project metadata is read
# through the API — no untrusted checkout — so pull_request_target is safe here.
on:
  pull_request_target:
    types: [opened, edited, reopened, synchronize, ready_for_review]
  workflow_dispatch:
    inputs:
      pr_number:
        description: "PR number to validate"
        required: true
        type: number

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

concurrency:
  # Serialize runs per PR (avoids duplicate sticky comments) but never cancel:
  # this check gates merges, so every event must reach a definitive conclusion.
  group: pr-metadata-validation-${{ github.event.pull_request.number || github.event.inputs.pr_number || github.run_id }}
  cancel-in-progress: false

jobs:
  validate-pr-metadata:
    name: Validate PR Metadata
    runs-on: ubuntu-latest
    steps:
      - name: Check linked issue and Shipping project fields
        uses: actions/github-script@60a0d83039c74a4aee543508d2ffcb1c3799cdea # v7.0.1
        env:
          PROJECTS_TOKEN: ${{ secrets.PROJECTS_TOKEN }}
        with:
          script: |
            const CHECK_MARKER = '<!-- pr-metadata-check -->';
            const BYPASS_LABEL = 'skip-pr-checks';

            const { owner, repo } = context.repo;

            // ---- Policy --------------------------------------------------------
            const REQUIRE_LINKED_ISSUE = true;
            const MIN_DESCRIPTION_WORDS = 25;
            const PROJECT_NAME = 'Shipping';
            const REQUIRED_PROJECT_FIELDS = ['Status', 'Source', 'Priority', 'Domain', 'Release'];
            const FAIL_WHEN_PROJECT_UNVERIFIABLE = true;

            // ---- Cross-repo policy (security-sensitive) ------------------------
            // closingIssuesReferences is same-repo only, so a cross-repo link can
            // only live in the PR body. Honor it ONLY for trusted authors and ONLY
            // for these same-org repos, so untrusted fork PRs can never drive the
            // privileged token at arbitrary repositories or probe private issues.
            const CLOSING_KEYWORDS = '(?:close[sd]?|fix(?:e[sd])?|resolve[sd]?)';
            const ALLOWED_CROSS_REPOS = new Set(['openmetadata-collate']);
            const TRUSTED_ASSOCIATIONS = new Set(['OWNER', 'MEMBER', 'COLLABORATOR']);

            const PR_LINKS_QUERY = `
              query($owner: String!, $repo: String!, $number: Int!) {
                repository(owner: $owner, name: $repo) {
                  pullRequest(number: $number) {
                    closingIssuesReferences(first: 25) {
                      nodes { number repository { name owner { login } } }
                    }
                  }
                }
              }`;

            const ISSUE_PROJECT_QUERY = `
              query($owner: String!, $repo: String!, $number: Int!) {
                repository(owner: $owner, name: $repo) {
                  issue(number: $number) {
                    projectItems(first: 25) {
                      nodes {
                        project { title }
                        fieldValues(first: 50) {
                          nodes {
                            __typename
                            ... on ProjectV2ItemFieldSingleSelectValue { name field { ... on ProjectV2FieldCommon { name } } }
                            ... on ProjectV2ItemFieldTextValue { text field { ... on ProjectV2FieldCommon { name } } }
                            ... on ProjectV2ItemFieldNumberValue { number field { ... on ProjectV2FieldCommon { name } } }
                            ... on ProjectV2ItemFieldIterationValue { title field { ... on ProjectV2FieldCommon { name } } }
                            ... on ProjectV2ItemFieldDateValue { date field { ... on ProjectV2FieldCommon { name } } }
                          }
                        }
                      }
                    }
                  }
                }
              }`;

            function elevatedClient() {
              const token = process.env.PROJECTS_TOKEN;
              return token ? new github.constructor({ auth: token }) : null;
            }

            const isSameRepo = (ref) => ref.owner === owner && ref.repo === repo;
            const refKey = (ref) => `${ref.owner}/${ref.repo}#${ref.number}`;
            const refLabel = (ref) => (isSameRepo(ref) ? `#${ref.number}` : refKey(ref));
            const dedupeRefs = (refs) => [...new Map(refs.map((r) => [refKey(r), r])).values()];

            async function loadPullRequest() {
              if (context.payload.pull_request) {
                return context.payload.pull_request;
              }
              const pull_number = Number(context.payload.inputs.pr_number);
              const { data } = await github.rest.pulls.get({ owner, repo, pull_number });
              return data;
            }

            // Same-repo links: authoritative, includes sidebar-linked issues.
            async function nativeLinkedRefs(prNumber) {
              const data = await github.graphql(PR_LINKS_QUERY, { owner, repo, number: prNumber });
              const nodes =
                (data.repository &&
                  data.repository.pullRequest &&
                  data.repository.pullRequest.closingIssuesReferences.nodes) ||
                [];
              return nodes.map((node) => ({
                owner: node.repository.owner.login,
                repo: node.repository.name,
                number: node.number,
              }));
            }

            // Trust the author for cross-repo refs if their PR association is already a trusted
            // value, or — since the default GITHUB_TOKEN cannot see *private* org membership and
            // reports such authors as CONTRIBUTOR — by confirming org membership with the elevated
            // token. Fork PRs from non-members still resolve to untrusted.
            async function isTrustedAuthor(pr) {
              let trusted = TRUSTED_ASSOCIATIONS.has(pr.author_association);
              const client = elevatedClient();
              if (!trusted && client && pr.user && pr.user.login) {
                try {
                  await client.rest.orgs.checkMembershipForUser({ org: owner, username: pr.user.login });
                  trusted = true; // 204 => org member (including private membership)
                } catch (error) {
                  trusted = false; // 404 => not a member
                }
              }
              return trusted;
            }

            // Cross-repo links: body-parsed, allowlisted repos only (caller gates on author trust).
            function crossRepoRefsFromBody(text) {
              const refs = [];
              const add = (refOwner, refRepo, number) => {
                if (refOwner === owner && ALLOWED_CROSS_REPOS.has(refRepo)) {
                  refs.push({ owner: refOwner, repo: refRepo, number: Number(number) });
                }
              };
              const shorthand = new RegExp(
                `\\b${CLOSING_KEYWORDS}\\b\\s*:?\\s*([\\w.-]+)/([\\w.-]+)#(\\d+)`,
                'gi'
              );
              const url = new RegExp(
                `\\b${CLOSING_KEYWORDS}\\b\\s*:?\\s*https?://github\\.com/([\\w.-]+)/([\\w.-]+)/issues/(\\d+)`,
                'gi'
              );
              let match;
              while ((match = shorthand.exec(text)) !== null) {
                add(match[1], match[2], match[3]);
              }
              while ((match = url.exec(text)) !== null) {
                add(match[1], match[2], match[3]);
              }
              return refs;
            }

            function hasProperDescription(body) {
              if (!body) {
                return false;
              }
              const meaningful = body.replace(/<!--[\s\S]*?-->/g, ' ').replace(/\s+/g, ' ').trim();
              const wordCount = meaningful ? meaningful.split(' ').filter(Boolean).length : 0;
              return wordCount >= MIN_DESCRIPTION_WORDS;
            }

            async function loadIssue(ref) {
              const client = isSameRepo(ref) ? github : elevatedClient();
              if (!client) {
                return { error: 'missing-token' };
              }
              try {
                const { data } = await client.rest.issues.get({
                  owner: ref.owner,
                  repo: ref.repo,
                  issue_number: ref.number,
                });
                return { issue: data };
              } catch (error) {
                return { error: error.status === 404 ? 'not-found' : error.message };
              }
            }

            async function loadIssueProjectItems(ref) {
              const client = elevatedClient();
              if (!client) {
                return { error: 'missing-token' };
              }
              try {
                const data = await client.graphql(ISSUE_PROJECT_QUERY, {
                  owner: ref.owner,
                  repo: ref.repo,
                  number: ref.number,
                });
                return { items: data.repository.issue.projectItems.nodes };
              } catch (error) {
                return { error: error.message };
              }
            }

            function resolveFieldValue(fieldValue) {
              const candidates = [fieldValue.name, fieldValue.text, fieldValue.title, fieldValue.date];
              const text = candidates.find((value) => value != null && String(value).trim() !== '');
              if (text != null) {
                return text;
              }
              return fieldValue.number != null ? String(fieldValue.number) : null;
            }

            function collectSetFields(item) {
              const setFields = new Map();
              for (const fieldValue of item.fieldValues.nodes) {
                const fieldName = fieldValue.field && fieldValue.field.name;
                const resolved = resolveFieldValue(fieldValue);
                if (fieldName && resolved != null) {
                  setFields.set(fieldName, resolved);
                }
              }
              return setFields;
            }

            async function collectProjectProblems(ref) {
              const result = await loadIssueProjectItems(ref);
              if (result.error) {
                if (!FAIL_WHEN_PROJECT_UNVERIFIABLE) {
                  core.warning(`Skipping project validation for ${refLabel(ref)}: ${result.error}`);
                  return [];
                }
                core.warning(`Project verification failed for ${refLabel(ref)}: ${result.error}`);
                const detail = result.error === 'missing-token'
                  ? 'the `PROJECTS_TOKEN` secret (a token with `read:project` and access to the linked repo) is not configured'
                  : 'the project query could not be completed (see the workflow run logs)';
                return [`Could not verify the **${PROJECT_NAME}** project on issue ${refLabel(ref)}: ${detail}.`];
              }
              const projectItem = (result.items || []).find(
                (item) => item.project && item.project.title === PROJECT_NAME
              );
              if (!projectItem) {
                return [`Linked issue ${refLabel(ref)} is not added to the **${PROJECT_NAME}** project.`];
              }
              const setFields = collectSetFields(projectItem);
              const problems = [];
              for (const field of REQUIRED_PROJECT_FIELDS) {
                if (!setFields.has(field)) {
                  problems.push(`Issue ${refLabel(ref)} is missing **${PROJECT_NAME} → ${field}**.`);
                }
              }
              return problems;
            }

            async function validateIssue(ref) {
              const loaded = await loadIssue(ref);
              if (loaded.error === 'not-found') {
                return { ref, problems: [`Linked issue ${refLabel(ref)} does not exist or is not accessible.`] };
              }
              if (loaded.error) {
                const detail = loaded.error === 'missing-token'
                  ? 'the `PROJECTS_TOKEN` secret is not configured'
                  : 'the issue lookup could not be completed (see the workflow run logs)';
                core.warning(`Issue lookup failed for ${refLabel(ref)}: ${loaded.error}`);
                return { ref, problems: [`Could not read linked issue ${refLabel(ref)}: ${detail}.`] };
              }
              const issue = loaded.issue;
              if (issue.pull_request) {
                return { ref, problems: [`${refLabel(ref)} is a pull request, not an issue.`] };
              }
              const problems = [];
              if (!hasProperDescription(issue.body)) {
                problems.push(
                  `Linked issue ${refLabel(ref)} needs a real description ` +
                  `(at least ${MIN_DESCRIPTION_WORDS} words covering the problem, repro, and expected behavior).`
                );
              }
              problems.push(...(await collectProjectProblems(ref)));
              return { ref, problems };
            }

            async function collectIssueProblems(pr) {
              const native = await nativeLinkedRefs(pr.number);
              const cross = (await isTrustedAuthor(pr))
                ? crossRepoRefsFromBody(`${pr.title || ''}\n${pr.body || ''}`)
                : [];
              const refs = dedupeRefs([...native, ...cross]);
              if (refs.length === 0) {
                return [
                  'No GitHub issue is linked. Link an issue in the **Development** section of the PR ' +
                  '(or add `Fixes #12345` to the description). For a same-org cross-repo issue, add ' +
                  '`Fixes open-metadata/<repo>#123` to the description.',
                ];
              }
              const validations = await Promise.all(refs.map(validateIssue));
              const validIssues = validations.filter((validation) => validation.problems.length === 0);
              const problems = [];
              if (validIssues.length === 0) {
                for (const validation of validations) {
                  problems.push(...validation.problems);
                }
              }
              return problems;
            }

            function buildFailureComment(problems) {
              const lines = [
                CHECK_MARKER,
                '### ❌ PR checklist incomplete',
                '',
                'This PR cannot be merged until the following are addressed on its linked issue:',
                '',
              ];
              for (const problem of problems) {
                lines.push(`- ${problem}`);
              }
              lines.push('');
              lines.push(
                `The fields live on the **linked issue** in the **${PROJECT_NAME}** project ` +
                '(open the issue → right sidebar → **Projects**). After you set them, ' +
                '**re-run this check** (or push a commit) — issue/project changes do not re-trigger it automatically.'
              );
              lines.push('');
              lines.push(`_Maintainers can bypass this check by adding the \`${BYPASS_LABEL}\` label._`);
              return lines.join('\n');
            }

            function buildSuccessComment() {
              return [
                CHECK_MARKER,
                '### ✅ PR checks passed',
                '',
                `The linked issue has a description and all required **${PROJECT_NAME}** project fields set. Thanks!`,
              ].join('\n');
            }

            async function syncStickyComment(prNumber, body, hadFailure) {
              const comments = await github.paginate(github.rest.issues.listComments, {
                owner,
                repo,
                issue_number: prNumber,
                per_page: 100,
              });
              const existing = comments.find((comment) => comment.body && comment.body.includes(CHECK_MARKER));
              if (hadFailure) {
                if (existing) {
                  await github.rest.issues.updateComment({ owner, repo, comment_id: existing.id, body });
                } else {
                  await github.rest.issues.createComment({ owner, repo, issue_number: prNumber, body });
                }
              } else if (existing) {
                await github.rest.issues.updateComment({ owner, repo, comment_id: existing.id, body });
              }
            }

            const pr = await loadPullRequest();

            if (pr.draft) {
              core.info('Draft PR — skipping metadata validation.');
              return;
            }
            if (pr.user && pr.user.type === 'Bot') {
              core.info(`PR opened by bot ${pr.user.login} — skipping metadata validation.`);
              return;
            }
            const labels = (pr.labels || []).map((label) => label.name);
            if (labels.includes(BYPASS_LABEL)) {
              core.info(`'${BYPASS_LABEL}' label present — skipping metadata validation.`);
              return;
            }

            const problems = [];
            if (REQUIRE_LINKED_ISSUE) {
              problems.push(...(await collectIssueProblems(pr)));
            }

            const hadFailure = problems.length > 0;
            const body = hadFailure ? buildFailureComment(problems) : buildSuccessComment();
            await syncStickyComment(pr.number, body, hadFailure);

            if (hadFailure) {
              core.setFailed(
                `PR metadata checklist incomplete: ${problems.length} item(s) need attention. See the PR comment.`
              );
            } else {
              core.info('All PR metadata checks passed.');
            }