# CodeQL scans for security vulnerabilities and coding errors across all
# languages in this repo. Results appear in the "Security" tab under
# "Code scanning alerts" and are enforced by branch protection rules.
name: "CodeQL"

on:
  push:
    branches: [ "main" ]
  pull_request:
    branches: [ "main" ]
  # Weekly scheduled scan catches newly disclosed vulnerabilities in
  # existing code, not just changes introduced by PRs.
  schedule:
    - cron: '38 11 * * 3'

jobs:
  analyze:
    name: Analyze (${{ matrix.language }})
    runs-on: ubuntu-latest
    permissions:
      # Required to upload SARIF results to the "Security" tab.
      security-events: write
      # Required to fetch internal or private CodeQL packs.
      packages: read
      # Only required for workflows in private repositories.
      actions: read
      contents: read

    strategy:
      fail-fast: false
      matrix:
        include:
          # GitHub Actions workflow linting — no build needed.
          - language: actions
            build-mode: none

          # Go uses "manual" build mode so we control exactly what gets
          # compiled. The default "autobuild" finds the Makefile and runs
          # the full CI pipeline (lint, test, snapshot release, etc.),
          # which is far more work than CodeQL needs. All it requires is
          # compiled Go source so it can build a type-resolved code graph
          # for analysis.
          - language: go
            build-mode: manual

    steps:
      - name: Checkout repository
        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2

        with:
          persist-credentials: false

      # Pin the Go toolchain to whatever go.mod declares so CodeQL
      # analyzes with the same version the project actually uses.
      # Only runs for the Go matrix entry.
      - name: Setup Go
        if: matrix.language == 'go'
        uses: actions/setup-go@4a3601121dd01d1626a1e23e37211e3254c1c06c # v6.4.0
        with:
          go-version-file: go.mod

      - name: Initialize CodeQL
        uses: github/codeql-action/init@c10b8064de6f491fea524254123dbe5e09572f13 # v4.35.1
        with:
          languages: ${{ matrix.language }}
          build-mode: ${{ matrix.build-mode }}

      # Minimal build for Go: compile all packages so CodeQL gets a full
      # type-resolved code graph for analysis.
      - name: Build (Go)
        if: matrix.build-mode == 'manual'
        shell: bash
        run: go build ./...

      - name: Perform CodeQL Analysis
        uses: github/codeql-action/analyze@c10b8064de6f491fea524254123dbe5e09572f13 # v4.35.1
        with:
          # The category tag lets GitHub associate SARIF results with the
          # correct language when branch protection checks for required
          # code scanning results.
          category: "/language:${{matrix.language}}"