一盘货跨境库存统一调度 — 多平台多国统一库存决策与分配引擎

"""
一盘货跨境库存统一调度系统
功能：多渠道库存聚合 + 最优分配 + 快拨决策 + 聚合采购
"""
import numpy as np
import pandas as pd
from dataclasses import dataclass, field
from typing import List, Dict, Tuple, Optional
from scipy.optimize import linprog
import warnings
warnings.filterwarnings('ignore')


@dataclass
class ChannelInventory:
    """渠道库存状态"""
    channel_id: str           # 'amazon_us', 'shopee_sg', 'tiktok_uk'
    sku_id: str
    stock: int                # 当前库存
    daily_sales: float        # 日均销量
    min_service_level: float  # 最低服务水平（fill rate）
    unit_margin: float        # 单位毛利($)
    reallocation_cost: float  # 从其他渠道调拨成本($件)
    lead_time_days: int       # 从中央仓调拨时间
    
    @property
    def doi(self) -> float:
        return self.stock / max(self.daily_sales, 0.01)
    
    @property
    def safety_stock_needed(self) -> float:
        return self.daily_sales * (self.lead_time_days + 7)  # 提前期+7天安全


class UnifiedInventoryEngine:
    """统一库存调度引擎"""
    
    def __init__(self):
        self.channels: Dict[str, List[ChannelInventory]] = {}
    
    def add_channel_inventory(self, inv: ChannelInventory):
        if inv.sku_id not in self.channels:
            self.channels[inv.sku_id] = []
        self.channels[inv.sku_id].append(inv)
    
    def compute_global_atp(self, sku_id: str) -> Dict:
        """计算全局可用库存"""
        if sku_id not in self.channels:
            return {}
        
        channels = self.channels[sku_id]
        total_stock = sum(c.stock for c in channels)
        total_demand = sum(c.daily_sales for c in channels)
        
        return {
            'sku_id': sku_id,
            'total_stock': total_stock,
            'total_daily_demand': total_demand,
            'global_doi': total_stock / max(total_demand, 0.01),
            'channels': len(channels),