"""Utility for finding OpenFace weight files"""
import os
from pathlib import Path
from glob import glob


def find_weight(filename: str) -> str:
    """Find weight file in various possible locations"""
    # Check environment variable
    env_dir = os.environ.get("OPENFACE_WEIGHT_DIR")
    if env_dir:
        p = Path(env_dir) / filename
        if p.is_file():
            return str(p)
    
    # Check package installation
    try:
        import openface as _of
        site_w = Path(_of.__path__[0]) / "weights" / filename
        if site_w.is_file():
            return str(site_w)
    except:
        pass
    
    # Check HuggingFace cache
    user_home = Path(os.environ.get("USERPROFILE", str(Path.home())))
    hf_root = user_home / ".cache" / "huggingface" / "hub"
    if hf_root.exists():
        hits = glob(str(hf_root / "**" / filename), recursive=True)
        if hits:
            return hits[0]
    
    # Check local weights directory
    local = Path("weights") / filename
    if local.is_file():
        return str(local)
    
    raise FileNotFoundError(f"Weight not found: {filename}")