name: C++ Tests

on:
  push:
    branches:
      - main
      - dev
      - "claude/**"
      - "feature/**"
  pull_request:
  # /test-cgal comment on any PR triggers the CGAL test suite manually.
  issue_comment:
    types: [created]

# ─────────────────────────────────────────────────────────────────────────────
# Job 1 — test-fast
#   Pure-math tests (Clausen, ImLi₂, Hyper-ideal geometry).
#   No CGAL, no Boost. Eigen + GTest only. Runs on ALL branches.
# ─────────────────────────────────────────────────────────────────────────────
jobs:
  test-fast:
    runs-on: eulernest
    container:
      image: git.eulernest.eu/conformallab/ci-cpp:latest

    steps:
      - uses: actions/checkout@v4

      - name: Configure (tests-only)
        run: cmake -S code -B build -DCMAKE_BUILD_TYPE=Release

      - name: Build
        run: nice -n 19 cmake --build build --target conformallab_tests -j$(nproc)

      - name: Run tests
        run: >
          ctest --test-dir build
          --output-on-failure
          --output-junit test-results.xml

      - name: Summary
        if: always()
        run: |
          if [ -f test-results.xml ]; then
            total=$(grep -o 'tests="[0-9]*"'     test-results.xml | grep -o '[0-9]*' | head -1)
            failed=$(grep -o 'failures="[0-9]*"' test-results.xml | grep -o '[0-9]*' | head -1)
            skipped=$(grep -o 'skipped="[0-9]*"' test-results.xml | grep -o '[0-9]*' | head -1)
            passed=$(( ${total:-0} - ${failed:-0} - ${skipped:-0} ))
            echo "FAST  ▸ TOTAL ${total:-0} | PASSED $passed | FAILED ${failed:-0} | SKIPPED ${skipped:-0}"
          fi

# ─────────────────────────────────────────────────────────────────────────────
# Job 2 — test-cgal
#   Full CGAL test suite (Phase 3–7, 158 tests).
#   Runs ONLY on pull requests (not on direct pushes to dev/main).
#   Starts only after test-fast succeeds.
#
#   Uses -DWITH_CGAL_TESTS=ON (not -DWITH_CGAL=ON) to avoid building
#   Viewer/GLFW — the CI container has no wayland-scanner.
#
#   Boost (libboost-dev) is already present in the container since the image rebuild.
# ─────────────────────────────────────────────────────────────────────────────
  # ─── CGAL tests: manual trigger via PR comment ───────────────────────────
  #
  # Trigger: write "/test-cgal" as a comment on any pull request.
  #
  # Why comment-triggered (not automatic on every PR push):
  #   The Pi runner has 3-4 GB RAM total with swap constantly loaded.
  #   Even with LOW_MEMORY_BUILD the CGAL build takes ~5 min and stresses
  #   the runner.  Triggering on every push would queue builds faster than
  #   the Pi can drain them.  A manual trigger gives full control: run the
  #   277-test suite when a PR is ready for review, not on every WIP commit.
  #
  # How it works:
  #   - `issue_comment` fires on all PR + issue comments.
  #   - The `if:` condition checks:
  #       1. Event is a comment (not a push or PR sync)
  #       2. The comment is on a PR (issue.pull_request != null)
  #       3. The comment body contains "/test-cgal"
  #   - The checkout uses refs/pull/N/head to get the PR branch, because
  #     `issue_comment` does not set GITHUB_REF to the PR branch by default.
  #
  # LOW_MEMORY_BUILD applies four RAM-saving measures so the build fits in
  # 2000 MB: -O0, PCH off, unity batch 1, --no-keep-memory linker.
  # See code/tests/cgal/CMakeLists.txt for the full explanation.
  test-cgal:
    needs: test-fast
    if: |
      github.event_name == 'issue_comment' &&
      github.event.issue.pull_request != null &&
      contains(github.event.comment.body, '/test-cgal')
    runs-on: eulernest
    container:
      image: git.eulernest.eu/conformallab/ci-cpp:latest
      # 2000 MB hard limit; 1000 MB swap headroom (memory-swap = RAM + swap).
      # Uses ~half of the Pi's 3-4 GB, leaving margin for OS + runner daemon.
      # With LOW_MEMORY_BUILD peak per TU is ~150-200 MB → well within limit.
      options: "--memory=2000m --memory-swap=3000m"

    steps:
      # Check out the PR branch, not the default branch.
      # issue_comment events set GITHUB_REF to the default branch; we need
      # refs/pull/N/head to get the actual PR code.
      - uses: actions/checkout@v4
        with:
          ref: refs/pull/${{ github.event.issue.number }}/head

      - name: Configure (LOW_MEMORY_BUILD — -O0, no PCH, unity batch 1)
        run: |
          cmake -S code -B build \
            -DWITH_CGAL_TESTS=ON \
            -DCMAKE_BUILD_TYPE=Release \
            -DCONFORMALLAB_LOW_MEMORY_BUILD=ON

      - name: Build CGAL-Tests
        run: nice -n 19 cmake --build build --target conformallab_cgal_tests -j1

      - name: Run CGAL-Tests
        run: >
          ctest --test-dir build
          -R "^cgal\."
          --output-on-failure
          --output-junit cgal-results.xml

      - name: Summary
        if: always()
        run: |
          if [ -f cgal-results.xml ]; then
            total=$(grep -o 'tests="[0-9]*"'     cgal-results.xml | grep -o '[0-9]*' | head -1)
            failed=$(grep -o 'failures="[0-9]*"' cgal-results.xml | grep -o '[0-9]*' | head -1)
            skipped=$(grep -o 'skipped="[0-9]*"' cgal-results.xml | grep -o '[0-9]*' | head -1)
            passed=$(( ${total:-0} - ${failed:-0} - ${skipped:-0} ))
            echo "CGAL  ▸ TOTAL ${total:-0} | PASSED $passed | FAILED ${failed:-0} | SKIPPED ${skipped:-0}"
          fi

      # ── Structural gate: doc/api/tests.md totals match ctest reality ───
      # Single source of truth for test counts (see doc/release-policy.md).
      # Reuses the already-built ./build dir via BUILD_DIR env var, so this
      # adds ~5 s on top of the existing CGAL job.
      - name: Verify test-count consistency (doc/api/tests.md)
        run: BUILD_DIR=build bash scripts/check-test-counts.sh

      # ── Structural gate: end-to-end smoke (try_it.sh) ──────────────────
      # The user-facing quick-start script: configure + build + run the
      # full ctest + run the Euclidean example on a bundled mesh.  If
      # this regresses, README quick-start instructions are broken.
      # try_it.sh creates its own build-try/ — accept the ~3 min cost as
      # the price of guaranteeing the documented workflow stays working.
      - name: End-to-end smoke test (scripts/try_it.sh)
        run: bash scripts/try_it.sh

# ─────────────────────────────────────────────────────────────────────────────
# Job 3 — quality-gates  (style + convention block)
#
# Trigger: write "/quality-gates" as a comment on any pull request.
#
# Cheap, deterministic checks (~30 s): license headers, CGAL conventions,
# codespell, shellcheck.  Runs independently of test-fast when comment-
# triggered (no `needs:` — the caller decides when to invoke it).
# ─────────────────────────────────────────────────────────────────────────────
  quality-gates:
    if: |
      github.event_name == 'issue_comment' &&
      github.event.issue.pull_request != null &&
      contains(github.event.comment.body, '/quality-gates')
    runs-on: eulernest
    container:
      image: git.eulernest.eu/conformallab/ci-cpp:latest

    steps:
      - uses: actions/checkout@v4
        with:
          ref: refs/pull/${{ github.event.issue.number }}/head

      - name: Install codespell + shellcheck (job-local)
        run: |
          apt-get update -qq
          apt-get install -y --no-install-recommends \
            codespell shellcheck

      - name: License headers (every C++ source carries MIT SPDX)
        run: bash scripts/quality/license-headers.sh

      - name: CGAL conventions (6 rules over CGAL public headers)
        run: python3 scripts/quality/cgal-conventions.py

      - name: codespell (docs + source comments + script messages)
        run: bash scripts/quality/codespell.sh

      - name: shellcheck (scripts/**/*.sh, severity=warning, strict)
        run: bash scripts/quality/shellcheck.sh --strict

      - name: Summary
        if: always()
        run: |
          echo "QUALITY ▸ all four gates passed."
          echo "  see scripts/quality/README.md for the full catalogue"
          echo "  (sanitizers, clang-tidy, coverage, etc. are local-only)"