"""
交易分类配置和推断逻辑

配置文件: config/category.yaml
"""
import yaml
from pathlib import Path

# =============================================================================
# 加载 YAML 配置
# =============================================================================

CONFIG_FILE = Path(__file__).parent / "config" / "category.yaml"

def load_config():
    """加载分类配置"""
    with open(CONFIG_FILE, "r", encoding="utf-8") as f:
        return yaml.safe_load(f)

def reload_config():
    """重新加载配置（配置文件修改后调用）"""
    global _config
    _config = load_config()

# 初始化加载
_config = load_config()


# =============================================================================
# 配置访问函数
# =============================================================================

def get_platform_merchants() -> list[str]:
    """获取需要重新分类的平台型商家列表"""
    return _config.get("平台商家", [])


# =============================================================================
# 分类推断函数
# =============================================================================

def infer_category(merchant: str, product: str, income_expense: str) -> tuple[str, bool]:
    """
    根据商户名称和商品信息推断交易分类
    
    Args:
        merchant: 交易对方/商户名称
        product: 商品说明
        income_expense: 收/支 ("收入" 或 "支出")
    
    Returns:
        (分类名称, 是否确定) - 如果无法确定分类，第二个值为 False
    """
    merchant_lower = merchant.lower()
    product_lower = product.lower()
    combined = merchant_lower + " " + product_lower
    
    # 收入类型处理
    if income_expense == "收入":
        for category, keywords in _config["收入分类"].items():
            for kw in keywords:
                if kw.lower() in combined:
                    return category, True
        return _config["默认分类"]["收入"], False  # 无法确定
    
    # 支出类型处理 - 按优先级顺序匹配
    for category, keywords in _config["支出分类"].items():
        for kw in keywords:
            if kw.lower() in combined:
                return category, True
    
    # 转账类特殊处理
    if "转账" in combined:
        return _config["默认分类"]["支出"], False  # 转账无法确定具体分类
    
    return _config["默认分类"]["支出"], False  # 无法确定


def get_all_categories() -> list:
    """获取所有支出分类列表"""
    return list(_config["支出分类"].keys()) + [_config["默认分类"]["支出"]]


def get_all_income_categories() -> list:
    """获取所有收入分类列表"""
    return list(_config["收入分类"].keys())


# =============================================================================
# 分类重推断（用于修正原始分类错误）
# =============================================================================

def reclassify_if_needed(original_category: str, merchant: str, product: str, 
                         income_expense: str) -> tuple[str, bool, int]:
    """
    检查是否需要重新分类，如果推断出更准确的分类则返回新分类
    
    Args:
        original_category: 原始分类
        merchant: 交易对方
        product: 商品说明
        income_expense: 收/支
    
    Returns:
        (分类名称, 是否已修改, 复核等级)
        
        复核等级:
            0 = 无需复核（分类确定或原分类可信）
            1 = 低优先级复核（分类被调整，需确认调整是否正确）
            2 = 高优先级复核（完全无法判断，原分类也是默认分类）
    """
    new_category, is_certain = infer_category(merchant, product, income_expense)
    
    default_category = _config["默认分类"].get(
        "支出" if income_expense == "支出" else "收入"
    )
    
    # 判断原分类是否为默认/笼统分类
    is_original_default = (
        original_category == default_category or 
        original_category in ["其他", "其他支出", "其他收入", ""]
    )
    
    # 情况1：推断出具体分类，且与原分类不同 → 调整分类，低优先级复核
    if new_category != default_category and new_category != original_category:
        return new_category, True, 1  # 低优先级复核
    
    # 情况2：推断失败，但原分类是具体分类 → 信任原分类，无需复核
    if not is_certain and not is_original_default:
        return original_category, False, 0  # 信任支付宝原分类
    
    # 情况3：推断失败，原分类也是默认分类 → 高优先级复核
    if not is_certain and is_original_default:
        return new_category, False, 2  # 高优先级复核
    
    # 情况4：分类确定且未调整 → 无需复核
    return original_category, False, 0


# =============================================================================
# 调试工具
# =============================================================================

def test_category(merchant: str, product: str = "", income_expense: str = "支出") -> None:
    """测试分类推断结果"""
    category, is_certain = infer_category(merchant, product, income_expense)
    review_level = "无" if is_certain else "高 ⚠️"
    print(f"商户: {merchant}")
    print(f"商品: {product}")
    print(f"收支: {income_expense}")
    print(f"分类: {category}")
    print(f"复核: {review_level}")
    print()


if __name__ == "__main__":
    print("=== 分类测试 ===\n")
    
    test_cases = [
        ("luckin coffee", "订单付款", "支出"),
        ("美团", "万达影城-美团App", "支出"),
        ("美团", "茶百道-美团App", "支出"),
        ("美团", "美宜佳-美团App", "支出"),
    ]
    
    for merchant, product, ie in test_cases:
        test_category(merchant, product, ie)