"""Check Python 3.11 syntax in lesson snippets without executing services."""

import ast
import json
from pathlib import Path


root = Path(__file__).resolve().parents[1]
files = [root / "app/lessons.json", *sorted((root / "public/content").glob("*.json"))]
checked = 0
errors = []
for path in files:
    lessons = json.loads(path.read_text(encoding="utf-8-sig"))
    for lesson in lessons:
        for index, step in enumerate(lesson["steps"], 1):
            if step.get("lang") not in {"python", "py"} or not step.get("code"):
                continue
            label = f"{path.stem}/{lesson['id']}/step-{index}"
            try:
                ast.parse(step["code"], filename=label, feature_version=(3, 11))
                checked += 1
            except SyntaxError as exc:
                errors.append(f"{label}: line {exc.lineno}: {exc.msg}")

if errors:
    raise SystemExit("\n".join(errors))
print(f"Python 3.11 AST: {checked} snippets passed across {len(files)} modules.")
print("Syntax only; dependencies, SQL, external services and failure drills are not executed.")