"""Project path routing: relative paths are resolved from the repository root (this file's directory).

中文「路由」在此指：把 ``input/screenshot.png`` 等相对路径统一映射到仓库根下的绝对路径。

Example::

    from routing import REPO_ROOT, route, INPUT_DIR, OUTPUT_DIR

    shot = route(\"input/screenshot.png\")
    same = INPUT_DIR / \"screenshot.png\"
    assert shot.resolve() == same.resolve()
"""

from __future__ import annotations

from pathlib import Path

REPO_ROOT: Path = Path(__file__).resolve().parent
INPUT_DIR: Path = REPO_ROOT / "input"
OUTPUT_DIR: Path = REPO_ROOT / "output"


def route(path: str | Path) -> Path:
    """Resolve ``path`` under ``REPO_ROOT`` when relative; absolute paths stay absolute."""
    p = Path(path)
    return p.resolve() if p.is_absolute() else (REPO_ROOT / p).resolve()


repo_path = route

__all__ = [
    "REPO_ROOT",
    "INPUT_DIR",
    "OUTPUT_DIR",
    "route",
    "repo_path",
]