import pandas as pd
import json
from typing import List, Dict, Any, Tuple
import os


class DataManager:
    """统一管理数据加载、验证和预处理"""

    # 字段映射（支持多种别名）
    FIELD_MAPPING = {
        'txId': ['txId', 'transaction_id', '交易ID', 'id'],
        'txDate': ['txDate', 'transaction_date', '交易日期', 'date'],
        'txTime': ['txTime', 'transaction_time', '交易时间', 'time'],
        'txAmount': ['txAmount', 'amount', '交易金额', '金额'],
        'txBalance': ['txBalance', 'balance', '余额', '交易后余额'],
        'txDirection': ['txDirection', 'direction', '交易方向', '收支'],
        'txSummary': ['txSummary', 'summary', '交易摘要', '摘要', '说明'],
        'txCounterparty': ['txCounterparty', 'counterparty', '交易对手', '对方账户'],
        'createdAt': ['createdAt', 'created_at', '创建时间']
    }

    # 必需字段
    REQUIRED_FIELDS = ['txId', 'txDate', 'txAmount', 'txDirection']

    @staticmethod
    def load_from_file(file_path: str) -> Tuple[List[Dict[str, Any]], pd.DataFrame]:
        """从JSON文件加载数据，支持字段别名"""

        if not os.path.exists(file_path):
            raise FileNotFoundError(f"数据文件不存在: {file_path}")

        with open(file_path, 'r', encoding='utf-8') as f:
            raw_data = json.load(f)

        if not isinstance(raw_data, list):
            raise ValueError("JSON文件内容必须是数组格式")

        if not raw_data:
            raise ValueError("数据文件为空")

        # 标准化字段名
        standardized_data = []
        for record in raw_data:
            standardized_record = {}
            for std_field, possible_names in DataManager.FIELD_MAPPING.items():
                for name in possible_names:
                    if name in record:
                        standardized_record[std_field] = record[name]
                        break

            # 保留原始数据中未映射的字段
            for key, value in record.items():
                if key not in [name for names in DataManager.FIELD_MAPPING.values() for name in names]:
                    standardized_record[key] = value

            standardized_data.append(standardized_record)

        # 转换为DataFrame并优化
        df = pd.DataFrame(standardized_data)
        df = DataManager._optimize_dataframe(df)

        return standardized_data, df

    @staticmethod
    def _optimize_dataframe(df: pd.DataFrame) -> pd.DataFrame:
        """优化DataFrame数据类型"""

        # 日期字段
        if 'txDate' in df.columns:
            df['txDate'] = pd.to_datetime(df['txDate'], errors='coerce').dt.date

        # 时间字段
        if 'txTime' in df.columns:
            df['txTime'] = df['txTime'].astype(str)

        # 金额字段
        for col in ['txAmount', 'txBalance']:
            if col in df.columns:
                df[col] = pd.to_numeric(df[col], errors='coerce')

        # 创建时间
        if 'createdAt' in df.columns:
            df['createdAt'] = pd.to_datetime(df['createdAt'], errors='coerce')

        # 分类字段
        if 'txDirection' in df.columns:
            df['txDirection'] = df['txDirection'].astype('category')

        return df

    @staticmethod
    def validate_data_schema(data: List[Dict[str, Any]]) -> Tuple[bool, List[str]]:
        """验证数据格式"""
        errors = []

        if not data:
            return False, ["数据集为空"]

        # 检查必需字段
        first_record = data[0]
        missing_fields = []
        for field in DataManager.REQUIRED_FIELDS:
            if field not in first_record:
                missing_fields.append(field)

        if missing_fields:
            errors.append(f"缺少必需字段: {', '.join(missing_fields)}")

        return len(errors) == 0, errors

    @staticmethod
    def format_data_summary(data: List[Dict[str, Any]]) -> str:
        """生成数据摘要"""
        if not data:
            return "数据集为空"

        df = pd.DataFrame(data)
        summary = []

        summary.append(f"记录总数: {len(data)}")

        if 'txDate' in df.columns:
            summary.append(f"日期范围: {df['txDate'].min()} 至 {df['txDate'].max()}")

        if 'txAmount' in df.columns:
            summary.append(f"金额范围: {df['txAmount'].min()} 至 {df['txAmount'].max()}")

        if 'txDirection' in df.columns:
            direction_counts = df['txDirection'].value_counts().to_dict()
            summary.append(f"收支分布: {direction_counts}")

        return " | ".join(summary)