"""Hugging Face API utilities"""

import re
from typing import Optional

from huggingface_hub import HfApi
from huggingface_hub.errors import RepositoryNotFoundError
from huggingface_hub.utils import validate_repo_id

try:
    from huggingface_hub import repo_exists as hf_repo_exists
    _use_official_repo_exists = True
except ImportError:
    hf_repo_exists = None
    _use_official_repo_exists = False


def extract_quantization(filename: str) -> str:
    """Extract quantization from GGUF filename"""
    match = re.search(r"((?:B?F16)|Q[0-9]+(?:_[0-9]+)?(?:_[A-Z]+)*)", filename, re.IGNORECASE)
    return match.group(1) if match else "Unknown"


def check_repo_exists(repo_id: str, api: HfApi) -> bool:
    """Check if a Hugging Face repository exists"""
    if _use_official_repo_exists and hf_repo_exists:
        return hf_repo_exists(repo_id, token=getattr(api, "token", None))
    
    try:
        api.list_repo_files(repo_id)
        return True
    except RepositoryNotFoundError:
        return False
    except Exception:
        return False


def get_gguf_files_from_repo(repo_id: str, api: HfApi) -> list:
    """Get list of .gguf files from a repository"""
    try:
        return [
            path
            for path in api.list_repo_files(repo_id)
            if isinstance(path, str) and path.endswith(".gguf")
        ]
    except Exception:
        return []


def extract_username(user_info: object) -> Optional[str]:
    """Extract username from HF user info object"""
    if isinstance(user_info, dict):
        return user_info.get("name") or user_info.get("username")
    return getattr(user_info, "name", None) or getattr(user_info, "username", None)