name: Train Phase 1 Classifier

on:
  workflow_dispatch:        # manual trigger from Actions UI
  schedule:
    - cron: '0 2 * * 0'    # weekly, Sunday 02:00 UTC

jobs:
  train:
    runs-on: ubuntu-latest
    timeout-minutes: 120

    steps:
      - uses: actions/checkout@v4

      - uses: actions/setup-python@v5
        with:
          python-version: '3.11'
          cache: pip

      - name: Install dependencies
        run: |
          python -m pip install --upgrade pip setuptools
          pip install numpy scipy pytest pytest-cov ruff
          pip install torch torchvision --index-url https://download.pytorch.org/whl/cpu
          pip install scikit-learn scikit-optimize joblib opencv-python
          pip install -e . --no-deps

      - name: Train Phase 1 ensemble + OOD detector
        run: python experiments/train_phase1.py --out experiments/checkpoints/phase1
        # No --fast flag — full training run (~30-60 min)

      - name: Verify checkpoint files exist
        run: |
          for f in model_0.pt model_1.pt model_2.pt model_3.pt model_4.pt ood_detector.pkl training_log.json; do
            test -f "experiments/checkpoints/phase1/$f" || (echo "Missing: $f" && exit 1)
          done
          echo "All checkpoint files present"

      - name: Print training summary
        run: |
          python - <<'PYEOF'
          import json, pathlib
          log = json.loads(pathlib.Path('experiments/checkpoints/phase1/training_log.json').read_text())
          results = log.get('results', {})
          config  = log.get('config', {})
          print('Val accuracy (CIM):', results.get('val_accuracy_cim', 'n/a'))
          print('Epochs:',             config.get('n_epochs', 'n/a'))
          print('Timestamp:',          log.get('timestamp', 'n/a'))
          PYEOF

      - name: Upload checkpoint artifact
        uses: actions/upload-artifact@v4
        with:
          name: phase1-checkpoint-latest
          path: experiments/checkpoints/phase1/
          retention-days: 90
          if-no-files-found: error