"""`_StoredSourcePaths.identity` is asked for every node, edge and hyperedge's
file, several times per item, during an update's reconcile pass. A graph has
far fewer distinct source files than items (graphify's own repo: ~1k files,
~18.7k nodes, ~38k edges, ~150k identity calls), and the answer depends only on
the stored path and roots fixed in __init__. It is computed once per file.
"""
from __future__ import annotations

from pathlib import Path

from graphify.build import _norm_source_file
from graphify.watch import _StoredSourcePaths


def _paths(tmp_path: Path, normalize=_norm_source_file) -> _StoredSourcePaths:
    out = tmp_path / "graphify-out"
    out.mkdir()
    return _StoredSourcePaths(
        {"nodes": [], "links": []},
        out=out,
        project_root=tmp_path,
        watch_root=tmp_path,
        normalize_source=normalize,
    )


def test_identity_is_computed_once_per_source_file(tmp_path):
    calls: list[str | None] = []

    def counting_normalize(p, root=None):
        calls.append(p)
        return _norm_source_file(p, root)

    paths = _paths(tmp_path, counting_normalize)
    files = ["src/a.py", "src/b.py", "lib\\c.py"]
    for f in files:
        paths.identity(f)
        paths.in_watch_root(f)
    first_pass = len(calls)
    assert first_pass > 0
    for _ in range(50):
        for f in files:
            paths.identity(f)
            paths.in_watch_root(f)
    assert len(calls) == first_pass, f"{len(calls)} normalizations for {len(files)} files"


def test_cached_answers_match_a_fresh_computation(tmp_path):
    paths = _paths(tmp_path)
    outside = (tmp_path.parent / "elsewhere" / "x.py").as_posix()
    cases = ["src/a.py", "./src/../src/a.py", "lib\\c.py", outside, "", None]
    for f in cases:
        for _ in range(2):  # first call fills the cache, second reads it
            assert paths.identity(f) == paths._identity_uncached(f)
            identity = paths._identity_uncached(f)
            expected = bool(identity) and Path(identity).is_relative_to(paths.watch_root)
            assert paths.in_watch_root(f) is expected
    assert paths.in_watch_root("src/a.py") is True
    assert paths.in_watch_root(outside) is False