name: CodeQL

# Static analysis (SAST) for TypeScript/JavaScript and Python sources.
# Findings upload to the GitHub Security tab as SARIF.
#
# Advisory only on first introduction — see docs/plans/2026-05-03-001-feat-automated-security-scans-plan.md.
# Promote to a required check after baseline triage (operator decision).

on:
  pull_request:
    branches: [main]
    paths-ignore: ['**.md', 'docs/**', 'LICENSE']
  push:
    branches: [main]
  schedule:
    # Weekly Monday 06:00 UTC — catches advisories newly published against
    # already-merged code without waiting for the next PR.
    - cron: '0 6 * * 1'

permissions:
  contents: read

concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: ${{ github.event_name == 'pull_request' }}

jobs:
  analyze:
    name: Analyze (${{ matrix.language }})
    runs-on: ubuntu-latest
    timeout-minutes: 60
    permissions:
      actions: read
      contents: read
      # security-events:write is what enables SARIF upload to the Security tab.
      security-events: write

    strategy:
      fail-fast: false
      matrix:
        language: [javascript-typescript, python]

    steps:
      - name: Checkout
        uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
        with:
          # Don't leave GITHUB_TOKEN in .git/config for downstream steps to read.
          persist-credentials: false

      - name: Initialize CodeQL
        uses: github/codeql-action/init@99df26d4f13ea111d4ec1a7dddef6063f76b97e9 # v4.37.0
        with:
          languages: ${{ matrix.language }}
          queries: security-and-quality
          # Exclude generated/vendored code; tune after first-run signal.
          # gitnexus/vendor/ holds tree-sitter-proto sources (regenerated, not authored).
          # CodeQL path filters use .gitignore-style globs and do NOT support
          # brace expansion — list each generated parser file separately.
          config: |
            paths-ignore:
              - '**/dist/**'
              - '**/node_modules/**'
              - 'gitnexus/vendor/**'
              - 'gitnexus/src/core/parsing/**/parser.c'
              - 'gitnexus/src/core/parsing/**/parser.js'
              # Test fixtures are intentionally synthetic inputs (broken/unused
              # code, malformed samples) used to exercise the analyzer. CodeQL
              # findings here are noise, not real bugs. The second glob also
              # covers fixtures nested deeper in the test tree, e.g.
              # test/integration/cfg/fixtures/ (the CFG/PDG hazard inputs that
              # deliberately contain use-before-init / unused-variable shapes).
              - '**/test/fixtures/**'
              - '**/test/**/fixtures/**'

      - name: Perform CodeQL Analysis
        uses: github/codeql-action/analyze@99df26d4f13ea111d4ec1a7dddef6063f76b97e9 # v4.37.0
        with:
          category: '/language:${{ matrix.language }}'