"""Tests for the local filesystem storage adapter."""

import pytest

from snapshot.storage import LocalFileStorage, create_storage, validate_key
from snapshot.storage.base import StorageAdapter


def _contract(adapter: StorageAdapter) -> None:
    """Run the shared storage contract against an adapter instance."""
    adapter.put("a/b/file1.txt", b"hello")
    adapter.put("a/b/file2.txt", b"world")
    adapter.put("c/file3.txt", b"!")

    assert adapter.get("a/b/file1.txt") == b"hello"
    assert adapter.exists("a/b/file1.txt")
    assert not adapter.exists("a/b/missing.txt")

    with pytest.raises(KeyError):
        adapter.get("a/b/missing.txt")

    assert adapter.list_keys() == [
        "a/b/file1.txt",
        "a/b/file2.txt",
        "c/file3.txt",
    ]
    assert adapter.list_keys("a/b") == [
        "a/b/file1.txt",
        "a/b/file2.txt",
    ]

    adapter.delete("a/b/file1.txt")
    adapter.delete("a/b/file1.txt")  # idempotent
    assert not adapter.exists("a/b/file1.txt")
    assert adapter.list_keys() == [
        "a/b/file2.txt",
        "c/file3.txt",
    ]


def test_contract(tmp_path):
    """Validate the adapter contract on a temporary directory."""
    adapter = LocalFileStorage(tmp_path)
    _contract(adapter)


def test_put_creates_parent_directories(tmp_path):
    """put() must create intermediate directories."""
    adapter = LocalFileStorage(tmp_path)
    adapter.put("deep/nested/key.bin", b"data")
    assert (tmp_path / "deep" / "nested" / "key.bin").read_bytes() == b"data"


def test_atomic_put_leaves_no_tmp_files(tmp_path):
    """Atomic writes must not leak temporary files."""
    adapter = LocalFileStorage(tmp_path)
    adapter.put("x/y/z.txt", b"payload")
    tmp_files = list(tmp_path.rglob("*.tmp-*"))
    assert tmp_files == []


def test_validate_key_rejects_bad_keys():
    """validate_key must reject unsafe key strings."""
    with pytest.raises(ValueError):
        validate_key("")
    with pytest.raises(ValueError):
        validate_key("/absolute/path")
    with pytest.raises(ValueError):
        validate_key("../escape")
    with pytest.raises(ValueError):
        validate_key("a\\b")


def test_get_missing_raises_key_error(tmp_path):
    """Reading a missing key must raise KeyError."""
    adapter = LocalFileStorage(tmp_path)
    with pytest.raises(KeyError):
        adapter.get("missing.bin")


def test_create_storage_custom_local_root(tmp_path):
    """create_storage must honor an explicit local_root directory."""
    custom_dir = tmp_path / "custom_versions"
    adapter = create_storage(
        "local",
        root_dir=tmp_path,
        local_root=str(custom_dir),
    )
    adapter.put("notebook.ipynb", b"data")
    assert (custom_dir / "notebook.ipynb").read_bytes() == b"data"


def test_create_storage_default_local_root(tmp_path):
    """create_storage must fall back to root_dir/.notebook_versions."""
    adapter = create_storage("local", root_dir=tmp_path)
    adapter.put("notebook.ipynb", b"data")
    expected = tmp_path / ".notebook_versions" / "notebook.ipynb"
    assert expected.read_bytes() == b"data"