"""系统配置加载 + Profile 覆盖。

读取 configs/system.yaml，如果设置了 EN_NEWS_PROFILE 环境变量，
则加载 configs/profiles/{name}.yaml 并深度合并覆盖。
"""

import logging
import os
from pathlib import Path
from typing import Any

import yaml

logger = logging.getLogger(__name__)

SYSTEM_CONFIG_PATH = Path("configs/system.yaml")
PROFILES_DIR = Path("configs/profiles")


def _deep_merge(base: dict, override: dict) -> dict:
    """深度合并两个字典，override 的值覆盖 base。"""
    result = base.copy()
    for key, value in override.items():
        if key in result and isinstance(result[key], dict) and isinstance(value, dict):
            result[key] = _deep_merge(result[key], value)
        else:
            result[key] = value
    return result


def load_system_config() -> dict[str, Any]:
    """加载系统配置，自动应用 EN_NEWS_PROFILE 覆盖。

    Returns:
        合并后的完整配置字典（已应用 profile 覆盖）
    """
    if not SYSTEM_CONFIG_PATH.exists():
        raise FileNotFoundError(f"系统配置文件不存在: {SYSTEM_CONFIG_PATH}")

    with open(SYSTEM_CONFIG_PATH, encoding="utf-8") as f:
        config: dict[str, Any] = yaml.safe_load(f) or {}

    # ── Profile 覆盖 ──────────────────────────────────
    profile_name = os.environ.get("EN_NEWS_PROFILE", "")
    if profile_name:
        profile_path = PROFILES_DIR / f"{profile_name}.yaml"
        if profile_path.exists():
            logger.info("📋 加载 Profile: %s (%s)", profile_name, profile_path)
            with open(profile_path, encoding="utf-8") as f:
                profile_cfg = yaml.safe_load(f) or {}
            config = _deep_merge(config, profile_cfg)
            logger.info("📋 Profile 覆盖已应用: proxy=%s, headful=%s, max_memory=%s",
                        config.get("proxy", {}).get("enabled"),
                        config.get("crawler", {}).get("headful"),
                        config.get("crawler", {}).get("max_memory_mb"))
        else:
            logger.warning("⚠️  Profile 文件不存在: %s", profile_path)

    return config