name: CI / Lint + Deploy

on:
  push:
    branches: ["main", "master"]
  pull_request:
    branches: ["main", "master"]
  workflow_dispatch:

jobs:
  # ─────────────────────────────────────────────────────────────────────────────
  # 1. CI — syntax + import smoke test
  # ─────────────────────────────────────────────────────────────────────────────
  ci:
    name: Syntax & Import Check
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - name: Set up Python 3.11
        uses: actions/setup-python@v5
        with:
          python-version: "3.11"

      - name: Install dependencies
        run: |
          python -m pip install --upgrade pip
          # Install CPU-only torch to keep CI fast
          pip install torch torchvision --index-url https://download.pytorch.org/whl/cpu
          pip install -r requirements.txt

      - name: Compile-check all Python modules
        run: |
          python -m py_compile \
            scripts/train_chestmnist.py \
            backend/main.py \
            frontend/app.py \
            model_utils.py

      - name: Import smoke test (no model files needed)
        run: |
          python - <<'PY'
          import ast, pathlib
          for f in ["scripts/train_chestmnist.py", "backend/main.py", "frontend/app.py", "model_utils.py"]:
              ast.parse(pathlib.Path(f).read_text())
              print(f"  {f} OK")
          print("All imports parseable.")
          PY

  # ─────────────────────────────────────────────────────────────────────────────
  # 2. Deploy — push code to Hugging Face Space (on main branch only)
  # ─────────────────────────────────────────────────────────────────────────────
  deploy:
    name: Deploy to Hugging Face Spaces
    if: (github.ref == 'refs/heads/main' || github.ref == 'refs/heads/master') && github.event_name == 'push'
    needs: ci
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - name: Set up Python 3.11
        uses: actions/setup-python@v5
        with:
          python-version: "3.11"

      - name: Install huggingface_hub
        run: pip install huggingface_hub

      - name: Push Space to Hugging Face Hub
        env:
          HF_TOKEN: ${{ secrets.HF_TOKEN }}
          HF_SPACE_REPO: ${{ secrets.HF_SPACE_REPO }}
          GITHUB_SHA: ${{ github.sha }}
        run: |
          python - <<'PY'
          import os
          from huggingface_hub import HfApi

          token      = os.environ["HF_TOKEN"]
          space_repo = os.environ["HF_SPACE_REPO"]   # e.g. "your-username/pneumoops"
          sha_tag    = f"build-{os.environ['GITHUB_SHA'][:7]}"

          api = HfApi(token=token)
          api.create_repo(repo_id=space_repo, repo_type="space", space_sdk="docker", exist_ok=True)

          api.upload_folder(
              repo_id=space_repo,
              repo_type="space",
              folder_path=".",
              commit_message=f"Deploy {sha_tag}",
              ignore_patterns=[
                  ".git/*", "__pycache__/*", "*.pyc",
                  ".venv/*", "venv/*",
                  "data/hf_cache/*",
              ],
          )

          try:
              api.create_tag(repo_id=space_repo, repo_type="space", tag=sha_tag)
          except Exception:
              pass   # tag already exists

          print(f"Deployed {sha_tag} → https://huggingface.co/spaces/{space_repo}")
          PY

      - name: Upload model artifacts to HF Model Hub
        # Only runs if HF_MODEL_REPO secret is set
        if: ${{ env.HF_MODEL_REPO != '' }}
        env:
          HF_TOKEN: ${{ secrets.HF_TOKEN }}
          HF_MODEL_REPO: ${{ secrets.HF_MODEL_REPO }}
          GITHUB_SHA: ${{ github.sha }}
        run: |
          python - <<'PY'
          import os
          from huggingface_hub import HfApi
          from pathlib import Path

          token      = os.environ["HF_TOKEN"]
          model_repo = os.environ["HF_MODEL_REPO"]
          sha_tag    = f"build-{os.environ['GITHUB_SHA'][:7]}"

          api = HfApi(token=token)
          api.create_repo(repo_id=model_repo, repo_type="model", exist_ok=True)

          model_dir = Path("models/chestmnist_mobilenetv3")
          if model_dir.exists():
              api.upload_folder(
                  repo_id=model_repo,
                  repo_type="model",
                  folder_path=str(model_dir),
                  commit_message=f"Upload model {sha_tag}",
              )
              print(f"Model artifacts uploaded → https://huggingface.co/models/{model_repo}")
          PY

  # ─────────────────────────────────────────────────────────────────────────────
  # 3. Deploy — push backend+frontend to Railway (on main branch only)
  # ─────────────────────────────────────────────────────────────────────────────
  deploy-railway:
    name: Deploy to Railway
    if: (github.ref == 'refs/heads/main' || github.ref == 'refs/heads/master') && github.event_name == 'push'
    needs: ci
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - name: Install Railway CLI
        run: npm install -g @railway/cli

      - name: Deploy to Railway
        env:
          RAILWAY_TOKEN: ${{ secrets.RAILWAY_TOKEN }}
        run: railway up --service pneumoops-backend --detach