"""Tests for rationale/docstring extraction in extract.py."""
import textwrap
from pathlib import Path
import pytest
from graphify.extract import extract_python


def _write_py(tmp_path: Path, code: str) -> Path:
    p = tmp_path / "sample.py"
    p.write_text(textwrap.dedent(code))
    return p


def test_module_docstring_extracted(tmp_path):
    path = _write_py(tmp_path, '''
        """This module handles authentication because legacy sessions were insecure."""
        def login(): pass
    ''')
    result = extract_python(path)
    rationale = [n for n in result["nodes"] if n.get("file_type") == "rationale"]
    assert len(rationale) >= 1
    assert any("authentication" in n["label"] for n in rationale)


def test_function_docstring_extracted(tmp_path):
    path = _write_py(tmp_path, '''
        def process():
            """We use chunked processing here because the full dataset exceeds RAM."""
            pass
    ''')
    result = extract_python(path)
    rationale = [n for n in result["nodes"] if n.get("file_type") == "rationale"]
    assert any("chunked" in n["label"] for n in rationale)


def test_class_docstring_extracted(tmp_path):
    path = _write_py(tmp_path, '''
        class Cache:
            """Chosen over Redis because we need zero external dependencies in the test env."""
            pass
    ''')
    result = extract_python(path)
    rationale = [n for n in result["nodes"] if n.get("file_type") == "rationale"]
    assert any("Redis" in n["label"] for n in rationale)


def test_rationale_comment_extracted(tmp_path):
    path = _write_py(tmp_path, '''
        def build():
            # NOTE: must run before compile() or linker will fail
            pass
    ''')
    result = extract_python(path)
    rationale = [n for n in result["nodes"] if n.get("file_type") == "rationale"]
    assert any("NOTE" in n["label"] for n in rationale)


def test_rationale_for_edges_present(tmp_path):
    path = _write_py(tmp_path, '''
        """Module docstring explaining the why."""
        def foo():
            """Function docstring with rationale."""
            pass
    ''')
    result = extract_python(path)
    rationale_edges = [e for e in result["edges"] if e.get("relation") == "rationale_for"]
    assert len(rationale_edges) >= 1


def test_short_docstring_ignored(tmp_path):
    """Trivial docstrings under 20 chars should not become rationale nodes."""
    path = _write_py(tmp_path, '''
        def foo():
            """Constructor."""
            pass
    ''')
    result = extract_python(path)
    rationale = [n for n in result["nodes"] if n.get("file_type") == "rationale"]
    assert len(rationale) == 0


def test_rationale_confidence_is_extracted(tmp_path):
    path = _write_py(tmp_path, '''
        """This module exists because we needed a standalone parser."""
        def parse(): pass
    ''')
    result = extract_python(path)
    rationale_edges = [e for e in result["edges"] if e.get("relation") == "rationale_for"]
    assert all(e.get("confidence") == "EXTRACTED" for e in rationale_edges)