"""
Providers Hook - Bridge 模块

本文件作为 bridge，当 fileLoc 安装时，从 src.shared.model_manager.device_and_provider 导入，
当 fileLoc 未安装时，使用下方 fallback 实现。
"""

import sys
from pathlib import Path
from typing import Any
from loguru import logger

# 动态查找 fileLoc src 目录
_current_file = Path(__file__).resolve()
for _parent in _current_file.parents:
    _src_dir = _parent / "src"
    if _src_dir.exists() and str(_parent) not in sys.path:
        sys.path.insert(0, str(_parent))
        break

try:
    from src.shared.model_manager.device_and_provider import (
        resolve_providers,
        apply_providers_to_session,
        apply_providers_to_model,
        apply_device_strategy,  # 2026-06-03 新增
        DEFAULT_CPU_PROVIDERS,
        DEFAULT_GPU_PROVIDERS,
    )

    # 适配: fileLoc 的 apply_providers_to_model 接受 providers list，
    # 而 ocr_platform 消费者传入 config dict，由 bridge 在中间层处理
    def apply_providers(
        model: Any,
        config: dict,
        session_paths: list[str],
    ) -> bool:
        providers = resolve_providers(config)
        if providers is None:
            return False
        return apply_providers_to_model(model, providers, session_paths)

    logger.debug("[providers_hook] Bridge: loaded from fileLoc")
except ImportError:
    # Fallback: 使用本地实现
    logger.info("[providers_hook] fileLoc not found, using local implementation")
    from typing import List, Optional

    DEFAULT_CPU_PROVIDERS = ["CPUExecutionProvider"]
    DEFAULT_GPU_PROVIDERS = ["CUDAExecutionProvider", "CPUExecutionProvider"]

    def resolve_providers(config: dict) -> Optional[List[str]]:
        providers = config.get('providers')
        if providers is not None:
            return providers
        device = config.get('device', 'cpu')
        if device in ('gpu', 'cuda'):
            return DEFAULT_GPU_PROVIDERS
        return DEFAULT_CPU_PROVIDERS

    def apply_providers_to_session(session: Any, providers: List[str]) -> bool:
        if session is None:
            return False
        try:
            if hasattr(session, 'set_providers'):
                session.set_providers(providers)
                return True
            if hasattr(session, 'session') and hasattr(session.session, 'set_providers'):
                session.session.set_providers(providers)
                return True
        except Exception as e:
            logger.warning(f"Failed to set providers: {e}")
        return False

    def apply_providers(model: Any, config: dict, session_paths: List[str]) -> bool:
        providers = resolve_providers(config)
        if providers is None:
            return False
        success = False
        for path in session_paths:
            session = _get_nested_attr(model, path)
            if session is not None and apply_providers_to_session(session, providers):
                logger.info(f"Applied providers via '{path}': {providers}")
                success = True
        return success

    # 别名，保持向后兼容
    apply_providers_to_model = apply_providers

    def apply_device_strategy(model: Any, config: dict, model_kind: str) -> bool:
        """[fallback] 无 fileLoc 时仅做日志，不做实际设备移动。"""
        logger.warning(
            f"[providers_hook] fileLoc not found, apply_device_strategy noop: "
            f"model_kind={model_kind}, device={config.get('device', 'cpu')}"
        )
        return True

    def _get_nested_attr(obj: Any, attr_path: str) -> Any:
        if obj is None:
            return None
        current = obj
        for attr_name in attr_path.split('.'):
            try:
                current = getattr(current, attr_name)
            except AttributeError:
                return None
        return current