from __future__ import annotations

import importlib.util
import sys
from pathlib import Path

import pytest

from gyxx_flow.core.layout import DataLayout

PROJECT_ROOT = Path(__file__).resolve().parents[1]
RUNTIME_ROOT = PROJECT_ROOT / "src" / "gyxx_flow" / "modules"


def _load_path_module(module: str, filename: str, monkeypatch, data_root: Path):
    monkeypatch.setenv("GYXX_DATA_ROOT", str(data_root))
    module_root = RUNTIME_ROOT / module
    monkeypatch.setenv("GYXX_MODULE_ROOT", str(module_root))
    path = module_root / filename
    name = f"_gyxx_test_paths_{module}"
    spec = importlib.util.spec_from_file_location(name, path)
    assert spec and spec.loader
    loaded = importlib.util.module_from_spec(spec)
    sys.modules[name] = loaded
    try:
        spec.loader.exec_module(loaded)
    finally:
        sys.modules.pop(name, None)
    return loaded


@pytest.mark.parametrize(
    ("module", "filename", "names"),
    [
        (
            "content_marketing",
            "runtime_paths.py",
            ("raw_root", "normalized_root", "curated_root", "exports_root"),
        ),
        (
            "product_commerce",
            "runtime_paths.py",
            (
                "RAW_DATA_ROOT",
                "NORMALIZED_DATA_ROOT",
                "CURATED_DATA_ROOT",
                "EXPORTS_DATA_ROOT",
            ),
        ),
        (
            "shop_intelligence",
            "paths.py",
            ("RAW_ROOT", "NORMALIZED_ROOT", "CURATED_ROOT", "EXPORTS_ROOT"),
        ),
        (
            "supply_chain",
            "paths.py",
            ("SHARED_ROOT", "NORMALIZED_ROOT", "CURATED_ROOT", "BACKUP_ROOT"),
        ),
    ],
)
def test_all_module_path_boundaries_use_the_canonical_data_tree(
    tmp_path: Path,
    monkeypatch,
    module: str,
    filename: str,
    names: tuple[str, str, str, str],
) -> None:
    data_root = tmp_path / "relocatable-data"
    loaded = _load_path_module(module, filename, monkeypatch, data_root)

    layers = ("raw", "normalized", "curated", "exports")
    for name, layer in zip(names, layers, strict=True):
        assert getattr(loaded, name) == data_root / "data" / layer / module
    assert not data_root.exists(), "path resolution must not mutate the filesystem"


def test_module_data_paths_cover_collected_and_exported_file_types(tmp_path: Path) -> None:
    paths = DataLayout(tmp_path).for_module("content_marketing")

    assert paths.raw_path("api", "response.json") == (
        tmp_path / "data" / "raw" / "content_marketing" / "api" / "response.json"
    )
    assert paths.raw_path("downloads", "source.xlsx") == (
        tmp_path / "data" / "raw" / "content_marketing" / "downloads" / "source.xlsx"
    )
    assert paths.raw_path("downloads", "source.xls") == (
        tmp_path / "data" / "raw" / "content_marketing" / "downloads" / "source.xls"
    )
    assert paths.raw_path("downloads", "source.csv") == (
        tmp_path / "data" / "raw" / "content_marketing" / "downloads" / "source.csv"
    )
    assert paths.export_path("reports", "weekly.md") == (
        tmp_path / "data" / "exports" / "content_marketing" / "reports" / "weekly.md"
    )
    assert list(tmp_path.iterdir()) == []


@pytest.mark.parametrize("unsafe", ["", "..", "a/b", "a\\b", "C:\\data"])
def test_module_data_paths_reject_unsafe_module_names(tmp_path: Path, unsafe: str) -> None:
    with pytest.raises(ValueError, match="path segment"):
        DataLayout(tmp_path).for_module(unsafe)


@pytest.mark.parametrize("unsafe", [("..", "escape.json"), ("C:\\", "escape.json")])
def test_module_data_paths_reject_paths_outside_the_layer(
    tmp_path: Path, unsafe: tuple[str, str]
) -> None:
    with pytest.raises(ValueError, match="escapes module data root"):
        DataLayout(tmp_path).for_module("product_commerce").raw_path(*unsafe)


@pytest.mark.parametrize("configured", ["", "   "])
@pytest.mark.parametrize(
    ("module", "filename", "root_name"),
    [
        ("content_marketing", "runtime_paths.py", "data_root"),
        ("product_commerce", "runtime_paths.py", "DATA_HOME"),
        ("shop_intelligence", "paths.py", "DATA_ROOT"),
        ("supply_chain", "paths.py", "DATA_ROOT"),
    ],
)
def test_blank_data_root_uses_the_project_var_default(
    monkeypatch,
    configured: str,
    module: str,
    filename: str,
    root_name: str,
) -> None:
    monkeypatch.setenv("GYXX_DATA_ROOT", configured)
    module_root = RUNTIME_ROOT / module
    monkeypatch.setenv("GYXX_MODULE_ROOT", str(module_root))
    path = module_root / filename
    name = f"_gyxx_test_blank_paths_{module}"
    spec = importlib.util.spec_from_file_location(name, path)
    assert spec and spec.loader
    loaded = importlib.util.module_from_spec(spec)
    sys.modules[name] = loaded
    try:
        spec.loader.exec_module(loaded)
    finally:
        sys.modules.pop(name, None)

    assert getattr(loaded, root_name) == PROJECT_ROOT / "var"