# .github/workflows/sonar.yml
# TRUSTED CONTEXT. Has SONAR_TOKEN.
# Rule: never execute anything that came out of the artifact. No build, no
# npm/pip install, no scripts, no PR-supplied scanner config. Data only.
#
# NOTE: workflow_run workflows are only picked up from the DEFAULT branch.
# Changes to this file take effect after they land on master.

name: SonarQube Cloud

on:
  workflow_run:
    workflows: [ "Build" ]
    types: [ completed ]

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

jobs:
  sonar:
    name: Analyze
    if: github.event.workflow_run.conclusion == 'success'
    runs-on: ubuntu-24.04
    env:
      BUILD_WRAPPER_OUT_DIR: bw-output
      SONAR_EXCLUSIONS: betterRenderer/**,ref/**,imgui/**,stb/**,build/**,bw-output/**
      SONAR_SCANNER_JAVA_OPTS: -Xmx5g
    steps:
      # Trusted copy of the repo config, used to overwrite anything the PR
      # might have tampered with (sonar-project.properties etc).
      - name: Checkout trusted config from master
        uses: actions/checkout@v5
        with:
          ref: master
          path: .trusted

      - name: Download analysis input
        uses: actions/download-artifact@v4
        with:
          name: sonar-input
          path: /tmp/sonar-input
          run-id: ${{ github.event.workflow_run.id }}
          github-token: ${{ secrets.GITHUB_TOKEN }}

      - name: Unpack analysis input
        run: |
          set -euo pipefail
          tar -xzf /tmp/sonar-input/workspace.tar.gz -C "$GITHUB_WORKSPACE"
          # Strip PR-controlled scanner configuration, restore the trusted one.
          rm -f "$GITHUB_WORKSPACE/sonar-project.properties" \
                "$GITHUB_WORKSPACE/.sonarcloud.properties"
          if [ -f "$GITHUB_WORKSPACE/.trusted/sonar-project.properties" ]; then
            cp "$GITHUB_WORKSPACE/.trusted/sonar-project.properties" "$GITHUB_WORKSPACE/"
          fi

      - name: Resolve and verify PR metadata
        id: meta
        env:
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
          REPO: ${{ github.repository }}
        run: |
          set -euo pipefail
          cd "$GITHUB_WORKSPACE"
          event=$(tr -d '\r\n' < .sonar-meta/event)
          echo "event=$event" >> "$GITHUB_OUTPUT"

          if [ "$event" != "pull_request" ]; then
            echo "Branch build, no PR parameters."
            exit 0
          fi

          pr=$(tr -d '\r\n' < .sonar-meta/pr_number)
          sha=$(tr -d '\r\n' < .sonar-meta/head_sha)

          # The artifact is attacker-controlled: validate shape, then confirm
          # against the API that this PR really has this head commit.
          [[ "$pr"  =~ ^[0-9]+$ ]]          || { echo "::error::bad PR number"; exit 1; }
          [[ "$sha" =~ ^[0-9a-f]{40}$ ]]    || { echo "::error::bad head sha";  exit 1; }

          api_sha=$(gh api "repos/$REPO/pulls/$pr" --jq '.head.sha')
          base=$(gh api "repos/$REPO/pulls/$pr" --jq '.base.ref')
          head=$(gh api "repos/$REPO/pulls/$pr" --jq '.head.ref')

          if [ "$api_sha" != "$sha" ]; then
            echo "::error::head sha mismatch (artifact=$sha api=$api_sha)"
            exit 1
          fi

          {
            echo "pr=$pr"
            echo "base=$base"
            echo "head=$head"
          } >> "$GITHUB_OUTPUT"

      # sonar.cfamily.taintAnalysis=false
      # it's a deliberate choice, due to memory exhausting of a Github-hosted runner.
      #
      # Why off?: The jobs were OOM-killed. It's a trade-off, we still get everything else.
      # Most bugs are caught though.
      - name: SonarQube Cloud scan (pull request)
        if: steps.meta.outputs.event == 'pull_request'
        uses: SonarSource/sonarqube-scan-action@fd88b7d7ccbaefd23d8f36f73b59db7a3d246602 # v6.0.0
        env:
          SONAR_TOKEN: ${{ secrets.SONAR_TOKEN }}
          SONAR_HOST_URL: https://sonarcloud.io
        with:
          args: >
            --define sonar.cfamily.compile-commands=${{ env.BUILD_WRAPPER_OUT_DIR }}/compile_commands.json
            --define sonar.cfamily.taintAnalysis=false
            --define sonar.exclusions=${{ env.SONAR_EXCLUSIONS }}
            --define sonar.scm.revision=${{ github.event.workflow_run.head_sha }}
            --define sonar.pullrequest.key=${{ steps.meta.outputs.pr }}
            --define sonar.pullrequest.branch=${{ steps.meta.outputs.head }}
            --define sonar.pullrequest.base=${{ steps.meta.outputs.base }}

      - name: SonarQube Cloud scan (branch)
        if: steps.meta.outputs.event != 'pull_request'
        uses: SonarSource/sonarqube-scan-action@fd88b7d7ccbaefd23d8f36f73b59db7a3d246602 # v6.0.0
        env:
          SONAR_TOKEN: ${{ secrets.SONAR_TOKEN }}
          SONAR_HOST_URL: https://sonarcloud.io
        with:
          args: >
            --define sonar.cfamily.compile-commands=${{ env.BUILD_WRAPPER_OUT_DIR }}/compile_commands.json
            --define sonar.cfamily.taintAnalysis=false
            --define sonar.exclusions=${{ env.SONAR_EXCLUSIONS }}
            --define sonar.branch.name=${{ github.event.workflow_run.head_branch }}
            --define sonar.scm.revision=${{ github.event.workflow_run.head_sha }}