#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
销售概览分析服务
"""

import pandas as pd
import numpy as np
from datetime import datetime
from collections import defaultdict
import json


def analyze_sale_overview(df, filename):
    """
    分析销售概览数据
    
    Args:
        df: 销售数据DataFrame
        filename: 文件名
    
    Returns:
        dict: 分析结果
    """
    try:
        print(f"开始分析销售概览数据: {filename}")
        print(f"数据形状: {df.shape}")
        
        # 1. 数据预处理
        df = preprocess_data(df)
        
        # 2. 计算总体指标
        summary = calculate_summary(df)
        
        # 3. 按品类分析
        categories = analyze_categories(df)
        
        # 4. 按SKU分析
        sku_data = analyze_skus(df)
        
        # 5. 趋势分析
        trends = analyze_trends(df)
        
        # 6. 异常检测
        anomalies = detect_anomalies(df)
        
        # 7. 构建结果
        results = {
            'summary': summary,
            'categories': categories['categories_data'],
            'category_list': categories['category_list'],
            'category_skus': categories['category_skus'],
            'data': sku_data['sku_data'],
            'sku_list': sku_data['sku_list'],
            'trends': trends,
            'anomalies': anomalies
        }
        
        print("销售概览分析完成")
        return results
        
    except Exception as e:
        print(f"分析销售概览时出错: {str(e)}")
        raise


def preprocess_data(df):
    """
    预处理数据
    """
    # 复制数据以避免修改原始数据
    df = df.copy()
    
    # 处理日期列
    if '订单创建时间' in df.columns:
        df['订单创建时间'] = pd.to_datetime(df['订单创建时间'], errors='coerce')
        # 提取日期部分
        df['日期'] = df['订单创建时间'].dt.date
    
    # 处理数值列
    numeric_columns = ['价格', '购买数量', '买家应付货款', '买家实际支付金额', '退款金额']
    for col in numeric_columns:
        if col in df.columns:
            df[col] = pd.to_numeric(df[col], errors='coerce')
    
    # 填充缺失值
    df = df.fillna({
        '价格': 0,
        '购买数量': 0,
        '买家应付货款': 0,
        '买家实际支付金额': 0,
        '退款金额': 0
    })
    
    # 确保SKU列存在
    if '商家编码' in df.columns:
        df['SKU'] = df['商家编码']
    elif '外部系统编号' in df.columns:
        df['SKU'] = df['外部系统编号']
    else:
        # 如果没有SKU列，使用商品名称作为SKU
        df['SKU'] = df['商品名称']
    
    # 确保品类列存在
    if '品类' not in df.columns:
        # 简单品类划分：基于商品名称
        df['品类'] = df['商品名称'].apply(lambda x: categorize_product(x))
    
    return df


def categorize_product(product_name):
    """
    根据商品名称简单分类
    """
    product_name = str(product_name).lower()
    if '腰垫' in product_name or '靠垫' in product_name:
        return '家居用品'
    elif '手机' in product_name or '电脑' in product_name:
        return '电子产品'
    elif '服装' in product_name or '鞋' in product_name:
        return '服装鞋包'
    else:
        return '其他'


def calculate_summary(df):
    """
    计算总体指标
    """
    total_quantity = df['购买数量'].sum()
    total_revenue = df['买家实际支付金额'].sum()
    avg_price = total_revenue / total_quantity if total_quantity > 0 else 0
    
    # 计算促销力度
    df['促销力度'] = 1 - (df['买家实际支付金额'] / df['买家应付货款'])
    df['促销力度'] = df['促销力度'].fillna(0)
    avg_promotion = df['促销力度'].mean() * 100  # 转换为百分比
    
    # 计算退款相关指标
    refunded_orders = df[df['退款状态'] != '没有申请退款']
    total_refund = refunded_orders['退款金额'].sum()
    refund_rate = len(refunded_orders) / len(df) * 100 if len(df) > 0 else 0
    
    summary = {
        'total_orders': len(df),
        'total_quantity': int(total_quantity),
        'total_revenue': round(total_revenue, 2),
        'avg_price': round(avg_price, 2),
        'avg_promotion': round(avg_promotion, 2),
        'total_refund': round(total_refund, 2),
        'refund_rate': round(refund_rate, 2)
    }
    
    return summary


def analyze_categories(df):
    """
    按品类分析
    """
    categories_data = {}
    category_list = []
    category_skus = defaultdict(list)
    
    # 按品类分组
    grouped = df.groupby('品类')
    
    for category, group in grouped:
        category_list.append(category)
        
        # 计算品类指标
        total_quantity = group['购买数量'].sum()
        total_revenue = group['买家实际支付金额'].sum()
        avg_price = total_revenue / total_quantity if total_quantity > 0 else 0
        
        # 计算促销力度
        group['促销力度'] = 1 - (group['买家实际支付金额'] / group['买家应付货款'])
        group['促销力度'] = group['促销力度'].fillna(0)
        avg_promotion = group['促销力度'].mean() * 100
        
        # 计算退款相关指标
        refunded_orders = group[group['退款状态'] != '没有申请退款']
        total_refund = refunded_orders['退款金额'].sum()
        refund_rate = len(refunded_orders) / len(group) * 100 if len(group) > 0 else 0
        
        # 趋势数据
        date_series = []
        quantity_series = []
        price_series = []
        
        # 按日期排序
        date_grouped = group.groupby('日期')
        for date in sorted(date_grouped.groups.keys()):
            date_series.append(str(date))
            date_data = date_grouped.get_group(date)
            quantity_series.append(int(date_data['购买数量'].sum()))
            avg_date_price = date_data['买家实际支付金额'].sum() / date_data['购买数量'].sum() if date_data['购买数量'].sum() > 0 else 0
            price_series.append(round(avg_date_price, 2))
        
        categories_data[category] = {
            'total_quantity': int(total_quantity),
            'total_revenue': round(total_revenue, 2),
            'avg_price': round(avg_price, 2),
            'avg_promotion': round(avg_promotion, 2),
            'total_refund': round(total_refund, 2),
            'refund_rate': round(refund_rate, 2),
            'date_series': date_series,
            'quantity_series': quantity_series,
            'price_series': price_series
        }
        
        # 收集该品类下的SKU
        skus = group['SKU'].unique().tolist()
        category_skus[category] = skus
    
    return {
        'categories_data': categories_data,
        'category_list': category_list,
        'category_skus': dict(category_skus)
    }


def analyze_skus(df):
    """
    按SKU分析
    """
    sku_data = {}
    sku_list = []
    
    # 按SKU分组
    grouped = df.groupby('SKU')
    
    for sku, group in grouped:
        sku_list.append(sku)
        
        # 计算SKU指标
        total_quantity = group['购买数量'].sum()
        total_revenue = group['买家实际支付金额'].sum()
        avg_price = total_revenue / total_quantity if total_quantity > 0 else 0
        
        # 计算促销力度
        group['促销力度'] = 1 - (group['买家实际支付金额'] / group['买家应付货款'])
        group['促销力度'] = group['促销力度'].fillna(0)
        avg_promotion = group['促销力度'].mean() * 100
        
        # 计算退款相关指标
        refunded_orders = group[group['退款状态'] != '没有申请退款']
        total_refund = refunded_orders['退款金额'].sum()
        refund_rate = len(refunded_orders) / len(group) * 100 if len(group) > 0 else 0
        
        # 趋势数据
        date_series = []
        quantity_series = []
        price_series = []
        
        # 按日期排序
        date_grouped = group.groupby('日期')
        for date in sorted(date_grouped.groups.keys()):
            date_series.append(str(date))
            date_data = date_grouped.get_group(date)
            quantity_series.append(int(date_data['购买数量'].sum()))
            avg_date_price = date_data['买家实际支付金额'].sum() / date_data['购买数量'].sum() if date_data['购买数量'].sum() > 0 else 0
            price_series.append(round(avg_date_price, 2))
        
        sku_data[sku] = {
            'total_quantity': int(total_quantity),
            'total_revenue': round(total_revenue, 2),
            'avg_price': round(avg_price, 2),
            'avg_promotion': round(avg_promotion, 2),
            'total_refund': round(total_refund, 2),
            'refund_rate': round(refund_rate, 2),
            'date_series': date_series,
            'quantity_series': quantity_series,
            'price_series': price_series
        }
    
    return {
        'sku_data': sku_data,
        'sku_list': sku_list
    }


def analyze_trends(df):
    """
    分析趋势数据
    """
    # 按日期分组
    date_grouped = df.groupby('日期')
    
    date_series = []
    quantity_series = []
    revenue_series = []
    avg_price_series = []
    avg_promotion_series = []
    
    for date in sorted(date_grouped.groups.keys()):
        date_series.append(str(date))
        date_data = date_grouped.get_group(date)
        
        quantity = date_data['购买数量'].sum()
        revenue = date_data['买家实际支付金额'].sum()
        avg_price = revenue / quantity if quantity > 0 else 0
        
        # 计算促销力度
        date_data['促销力度'] = 1 - (date_data['买家实际支付金额'] / date_data['买家应付货款'])
        date_data['促销力度'] = date_data['促销力度'].fillna(0)
        avg_promotion = date_data['促销力度'].mean() * 100
        
        quantity_series.append(int(quantity))
        revenue_series.append(round(revenue, 2))
        avg_price_series.append(round(avg_price, 2))
        avg_promotion_series.append(round(avg_promotion, 2))
    
    trends = {
        'date_series': date_series,
        'quantity_series': quantity_series,
        'revenue_series': revenue_series,
        'avg_price_series': avg_price_series,
        'avg_promotion_series': avg_promotion_series
    }
    
    return trends


def detect_anomalies(df):
    """
    检测异常数据
    """
    anomalies = []
    
    # 按SKU分组检测异常
    grouped = df.groupby('SKU')
    
    for sku, group in grouped:
        # 检测销量异常
        quantity_mean = group['购买数量'].mean()
        quantity_std = group['购买数量'].std()
        if quantity_std > 0:
            for idx, row in group.iterrows():
                quantity = row['购买数量']
                z_score = abs((quantity - quantity_mean) / quantity_std)
                if z_score > 2.5:
                    anomalies.append({
                        'date': str(row['日期']) if pd.notna(row['日期']) else '未知',
                        'sku': sku,
                        'type': 'quantity_spike' if quantity > quantity_mean else 'quantity_drop',
                        'reason': f'销量异常，偏离均值 {z_score:.2f} 个标准差',
                        'value': float(quantity),
                        'expected': float(quantity_mean),
                        'deviation': float(z_score)
                    })
        
        # 检测价格异常
        price_mean = group['价格'].mean()
        price_std = group['价格'].std()
        if price_std > 0:
            for idx, row in group.iterrows():
                price = row['价格']
                z_score = abs((price - price_mean) / price_std)
                if z_score > 2.5:
                    anomalies.append({
                        'date': str(row['日期']) if pd.notna(row['日期']) else '未知',
                        'sku': sku,
                        'type': 'price_spike' if price > price_mean else 'price_drop',
                        'reason': f'价格异常，偏离均值 {z_score:.2f} 个标准差',
                        'value': float(price),
                        'expected': float(price_mean),
                        'deviation': float(z_score)
                    })
    
    anomaly_count = len(anomalies)
    anomaly_rate = (anomaly_count / len(df)) * 100 if len(df) > 0 else 0
    
    return {
        'anomaly_count': anomaly_count,
        'anomaly_rate': round(anomaly_rate, 2),
        'anomalies': anomalies
    }