From ca4f910012f8e01d2b3a6e2a4716fe6e672a0127 Mon Sep 17 00:00:00 2001
From: spdis <q17721073823@outlook.com>
Date: Sun, 27 Jul 2025 11:21:57 +0800
Subject: [PATCH] =?UTF-8?q?=E6=B7=BB=E5=8A=A0=20inventory=5Fmanager.py?=
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---
 inventory_manager.py | 632 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 632 insertions(+)
 create mode 100644 inventory_manager.py

diff --git a/inventory_manager.py b/inventory_manager.py
new file mode 100644
index 0000000..0c61026
--- /dev/null
+++ b/inventory_manager.py
@@ -0,0 +1,632 @@
+import json
+from decimal import Decimal
+from datetime import datetime
+import ijson
+import copy
+
+class InventoryManager:
+    """库存管理系统核心类
+    
+    核心特性：
+    - 流式JSON处理（支持GB级文件）
+    - 自动快照机制（每50条记录）
+    - 乱序插入自动重计算
+    - 严格时间倒序维护
+    - 进度回调支持
+    """
+
+    def __init__(self, data_path):
+        self.data_path = data_path
+        self.snapshot_interval = 50
+        self.need_calculate = 0  # 距离上次快照的记录数
+        
+        # 检查数据文件是否存在，不存在则创建
+        import os
+        if not os.path.exists(self.data_path):
+            self.initialize_data_file()
+        
+    def process_transaction(self, new_txn, progress_callback=None):
+        """处理新交易记录（核心入口函数）
+        
+        参数：
+        new_txn -- 新交易记录字典
+        progress_callback -- 进度回调函数 callback(current, total, message)
+        
+        返回：
+        处理结果字典 {"success": bool, "message": str, "recalculated_count": int}
+        """
+        try:
+            # 1. 验证和预处理新记录
+            if not self._validate_transaction(new_txn):
+                return {"success": False, "message": "交易记录格式错误", "recalculated_count": 0}
+            
+            # 2. 添加daily_sequence
+            new_txn['daily_sequence'] = self._get_next_sequence(new_txn['time'])
+            
+            # 3. 检查是否需要乱序插入处理
+            insert_position = self._find_insert_position(new_txn)
+            
+            if insert_position == 0:
+                # 最新记录，直接插入
+                return self._insert_latest_transaction(new_txn, progress_callback)
+            else:
+                # 乱序插入，需要重计算
+                return self._insert_historical_transaction(new_txn, insert_position, progress_callback)
+                
+        except Exception as e:
+            if "库存不足" in str(e):
+                return {"success": False, "message": "库存不足", "recalculated_count": 0}
+            return {"success": False, "message": f"处理失败: {str(e)}", "recalculated_count": 0}
+    
+    def _validate_transaction(self, txn):
+        """验证交易记录格式"""
+        required_fields = ['product', 'type', 'weight', 'time']
+        if txn['type'] == '入库':
+            required_fields.append('price')
+        
+        for field in required_fields:
+            if field not in txn:
+                return False
+        
+        # 验证数据类型
+        try:
+            Decimal(txn['weight'])
+            if txn['type'] == '入库':
+                Decimal(txn['price'])
+            datetime.strptime(txn['time'], '%Y-%m-%d')
+        except:
+            return False
+            
+        return True
+    
+    def _find_insert_position(self, new_txn):
+        """找到新记录应该插入的位置（流式读取）"""
+        position = 0
+        new_date = new_txn['time']
+        new_seq = new_txn['daily_sequence']
+        
+        try:
+            with open(self.data_path, 'r', encoding='utf-8') as f:
+                data = json.load(f)
+            
+            for i, txn in enumerate(data['transactions']):
+                if txn.get('is_snapshot'):
+                    continue
+                    
+                txn_date = txn.get('time', '')
+                txn_seq = txn.get('daily_sequence', 0)
+                
+                # 比较日期和序列号
+                if (new_date > txn_date or 
+                    (new_date == txn_date and new_seq > txn_seq)):
+                    return position
+                position += 1
+            
+            return position
+            
+        except:
+            return 0
+    
+    def _insert_latest_transaction(self, new_txn, progress_callback):
+        """插入最新记录（无需重计算）"""
+        try:
+            with open(self.data_path, 'r', encoding='utf-8') as f:
+                data = json.load(f)
+            
+            # 如果是出库，先计算价格
+            if new_txn['type'] == '出库':
+                new_txn['price'] = self.calculate_outbound_price(new_txn['product'], new_txn['time'])
+            
+            # 更新产品库存
+            if not self._update_product_inventory(data['products'], new_txn):
+                return {"success": False, "message": "库存不足", "recalculated_count": 0}
+            
+            # 插入记录
+            data['transactions'].insert(0, new_txn)
+            
+            # 检查是否需要创建快照
+            self.need_calculate += 1
+            if self.need_calculate >= self.snapshot_interval:
+                snapshot = self._create_snapshot(data['products'])
+                data['transactions'].insert(0, snapshot)
+                self.need_calculate = 0
+            
+            # 保存数据
+            with open(self.data_path, 'w', encoding='utf-8') as f:
+                json.dump(data, f, indent=2, ensure_ascii=False)
+            
+            return {"success": True, "message": "记录添加成功", "recalculated_count": 0}
+            
+        except Exception as e:
+            raise Exception(f"插入最新记录失败: {str(e)}")
+    
+    def _insert_historical_transaction(self, new_txn, insert_position, progress_callback):
+        """插入历史记录并重计算"""
+        try:
+            with open(self.data_path, 'r', encoding='utf-8') as f:
+                data = json.load(f)
+            
+            # 1. 找到基准快照
+            base_snapshot = self._find_base_snapshot(new_txn['time'], data['transactions'])
+            
+            # 2. 如果是出库，需要在重计算过程中处理价格
+            # 这里不预先计算价格，因为需要基于重计算后的状态
+            
+            # 3. 插入新记录到正确位置
+            data['transactions'].insert(insert_position, new_txn)
+            
+            # 4. 删除插入位置之后的所有快照
+            self._remove_snapshots_after_position(data['transactions'], insert_position)
+            
+            # 5. 重计算从基准快照开始的所有记录
+            recalculated_count = self._recalculate_from_snapshot(
+                data, base_snapshot, insert_position, progress_callback
+            )
+            
+            # 6. 保存数据
+            with open(self.data_path, 'w', encoding='utf-8') as f:
+                json.dump(data, f, indent=2, ensure_ascii=False)
+            
+            return {
+                "success": True, 
+                "message": f"历史记录插入成功，重计算了{recalculated_count}条记录", 
+                "recalculated_count": recalculated_count
+            }
+            
+        except Exception as e:
+            raise Exception(f"插入历史记录失败: {str(e)}")
+    
+    def _find_base_snapshot(self, target_date, transactions):
+        """找到目标日期之前最近的快照"""
+        for txn in reversed(transactions):
+            if (txn.get('is_snapshot') and 
+                txn.get('timestamp', '') <= target_date):
+                return txn
+        
+        # 如果没有找到快照，返回空的产品状态
+        return {
+            'is_snapshot': True,
+            'timestamp': '1900-01-01',
+            'products': {}
+        }
+    
+    def _remove_snapshots_after_position(self, transactions, position):
+        """删除指定位置之后的所有快照"""
+        i = 0
+        while i < len(transactions):
+            if i > position and transactions[i].get('is_snapshot'):
+                transactions.pop(i)
+            else:
+                i += 1
+    
+    def delete_transaction(self, transaction_index, progress_callback=None):
+        """删除指定的交易记录并重计算
+        
+        参数：
+        transaction_index -- 要删除的交易记录在transactions列表中的索引
+        progress_callback -- 进度回调函数 callback(current, total, message)
+        
+        返回：
+        处理结果字典 {"success": bool, "message": str, "recalculated_count": int}
+        """
+        try:
+            with open(self.data_path, 'r', encoding='utf-8') as f:
+                data = json.load(f)
+            
+            # 检查索引是否有效
+            if transaction_index < 0 or transaction_index >= len(data['transactions']):
+                return {"success": False, "message": "无效的交易记录索引", "recalculated_count": 0}
+            
+            # 获取要删除的交易记录
+            target_txn = data['transactions'][transaction_index]
+            
+            # 不能删除快照记录
+            if target_txn.get('is_snapshot'):
+                return {"success": False, "message": "不能删除快照记录", "recalculated_count": 0}
+            
+            # 找到删除记录之前最近的快照
+            base_snapshot = self._find_base_snapshot(target_txn['time'], data['transactions'][:transaction_index])
+            
+            # 删除目标记录
+            deleted_txn = data['transactions'].pop(transaction_index)
+            
+            # 删除该位置之后的所有快照
+            self._remove_snapshots_after_position(data['transactions'], transaction_index - 1)
+            
+            # 重计算从基准快照开始的所有记录
+            recalculated_count = self._recalculate_from_snapshot(
+                data, base_snapshot, transaction_index - 1, progress_callback
+            )
+            
+            # 保存数据
+            with open(self.data_path, 'w', encoding='utf-8') as f:
+                json.dump(data, f, indent=2, ensure_ascii=False)
+            
+            return {
+                "success": True,
+                "message": f"交易记录删除成功，重计算了{recalculated_count}条记录",
+                "recalculated_count": recalculated_count
+            }
+            
+        except Exception as e:
+            return {"success": False, "message": f"删除失败: {str(e)}", "recalculated_count": 0}
+    
+    def find_transaction_index(self, product_name, transaction_time, transaction_type, weight):
+        """根据交易记录的关键信息查找其在transactions列表中的索引
+        
+        参数：
+        product_name -- 产品名称
+        transaction_time -- 交易时间
+        transaction_type -- 交易类型（入库/出库）
+        weight -- 重量
+        
+        返回：
+        交易记录的索引，如果未找到返回-1
+        """
+        try:
+            with open(self.data_path, 'r', encoding='utf-8') as f:
+                data = json.load(f)
+            
+            for i, txn in enumerate(data['transactions']):
+                if (not txn.get('is_snapshot') and
+                    txn.get('product') == product_name and
+                    txn.get('time') == transaction_time and
+                    txn.get('type') == transaction_type and
+                    abs(float(txn.get('weight', 0)) - float(weight)) < 0.00000001):  # 浮点数比较
+                    return i
+            
+            return -1
+            
+        except Exception as e:
+            print(f"查找交易记录索引失败: {str(e)}")
+            return -1
+    
+    def delete_product(self, product_name, progress_callback=None):
+        """删除产品及其所有相关交易记录
+        
+        参数：
+        product_name -- 要删除的产品名称
+        progress_callback -- 进度回调函数 callback(current, total, message)
+        
+        返回：
+        处理结果字典 {"success": bool, "message": str, "deleted_transactions": int}
+        """
+        try:
+            with open(self.data_path, 'r', encoding='utf-8') as f:
+                data = json.load(f)
+            
+            # 确保产品名是字符串类型
+            product_name_str = str(product_name)
+            
+            # 检查产品是否存在
+            if product_name_str not in data["products"]:
+                return {"success": False, "message": f"未找到产品: {product_name_str}", "deleted_transactions": 0}
+            
+            # 统计要删除的交易记录数量
+            deleted_count = 0
+            
+            # 删除产品
+            del data["products"][product_name_str]
+            
+            # 删除相关交易记录，保留快照记录
+            original_count = len(data["transactions"])
+            data["transactions"] = [t for t in data["transactions"] 
+                                   if str(t.get("product")) != product_name_str or t.get("is_snapshot")]
+            
+            deleted_count = original_count - len(data["transactions"])
+            
+            # 如果删除了交易记录，需要重新计算所有快照
+            if deleted_count > 0:
+                # 删除所有快照，重新计算
+                data["transactions"] = [t for t in data["transactions"] if not t.get("is_snapshot")]
+                
+                # 重新计算所有产品的库存状态
+                self._recalculate_all_products(data, progress_callback)
+            
+            # 保存数据
+            with open(self.data_path, 'w', encoding='utf-8') as f:
+                json.dump(data, f, indent=2, ensure_ascii=False)
+            
+            return {
+                "success": True,
+                "message": f"产品删除成功，删除了{deleted_count}条相关交易记录",
+                "deleted_transactions": deleted_count
+            }
+            
+        except Exception as e:
+            return {"success": False, "message": f"删除产品失败: {str(e)}", "deleted_transactions": 0}
+    
+    def _recalculate_all_products(self, data, progress_callback):
+        """重新计算所有产品的库存状态"""
+        # 重置所有产品状态
+        for product_name in data["products"]:
+            data["products"][product_name] = {
+                "total_weight": "0.00000000",
+                "avg_price": "0.00000000"
+            }
+        
+        # 按时间正序排序所有交易记录
+        transactions = [t for t in data["transactions"] if not t.get("is_snapshot")]
+        transactions.sort(key=lambda x: (x.get('time', ''), x.get('daily_sequence', 0)))
+        
+        # 重新处理所有交易记录
+        processed_count = 0
+        snapshot_count = 0
+        
+        for i, txn in enumerate(transactions):
+            if progress_callback:
+                progress_callback(i + 1, len(transactions), f"重新计算交易记录: {txn.get('product', '')}")
+            
+            if txn['type'] == '入库':
+                self._update_product_inventory(data["products"], txn)
+            elif txn['type'] == '出库':
+                # 基于当前重算状态计算出库价格，避免循环依赖
+                txn['price'] = self._calculate_outbound_price_from_products(data["products"], txn['product'], txn['time'])
+                if not self._update_product_inventory(data["products"], txn):
+                    # 如果重计算过程中发现库存不足，则回滚并返回错误
+                    raise Exception("重计算过程中发现库存不足")
+            
+            processed_count += 1
+            snapshot_count += 1
+            
+            # 每50条记录创建快照
+            if snapshot_count >= self.snapshot_interval:
+                snapshot = self._create_snapshot(data["products"])
+                # 插入快照到正确位置
+                insert_position = self._find_insert_position_for_snapshot(data['transactions'], snapshot)
+                data['transactions'].insert(insert_position, snapshot)
+                snapshot_count = 0
+        
+        # 更新transactions列表为重新排序后的记录
+        data['transactions'] = [t for t in data['transactions'] if t.get('is_snapshot')] + transactions
+        # 重新按时间倒序排序
+        data['transactions'].sort(key=lambda x: (x.get('time', x.get('timestamp', '')), x.get('daily_sequence', 0)), reverse=True)
+
+    def _recalculate_from_snapshot(self, data, base_snapshot, start_position, progress_callback):
+        """从快照开始重计算所有记录"""
+        # 初始化产品状态 - 从快照复制，确保所有当前存在的产品都有正确的初始状态
+        products = copy.deepcopy(base_snapshot.get('products', {}))
+        
+        # 确保当前数据中存在但快照中不存在的产品也被正确初始化为0
+        for product_name in data.get('products', {}):
+            if product_name not in products:
+                products[product_name] = {
+                    'total_weight': '0.00000000',
+                    'avg_price': '0.00000000'
+                }
+        
+        # 收集需要重计算的记录 - 从基准快照开始的所有记录
+        records_to_process = []
+        base_timestamp = base_snapshot.get('timestamp', '1900-01-01')
+        
+        for i, txn in enumerate(data['transactions']):
+            if (not txn.get('is_snapshot') and 
+                txn.get('time', '') >= base_timestamp):
+                records_to_process.append((i, txn))
+        
+        # 按时间正序排序进行重计算，确保库存状态正确重建
+        records_to_process.sort(key=lambda x: (x[1].get('time', ''), x[1].get('daily_sequence', 0)))
+        
+        total_records = len(records_to_process)
+        processed_count = 0
+        snapshot_count = 0
+        
+        for original_index, txn in records_to_process:
+            # 更新进度
+            if progress_callback:
+                progress_callback(processed_count, total_records, f"重计算记录 {processed_count+1}/{total_records}")
+            
+            # 处理交易记录
+            if txn['type'] == '入库':
+                self._update_product_inventory(products, txn)
+            elif txn['type'] == '出库':
+                # 基于当前重算状态计算出库价格，避免循环依赖
+                txn['price'] = self._calculate_outbound_price_from_products(products, txn['product'], txn['time'])
+                if not self._update_product_inventory(products, txn):
+                    raise Exception("重计算过程中发现库存不足")
+            
+            processed_count += 1
+            snapshot_count += 1
+            
+            # 每50条记录创建快照
+            if snapshot_count >= self.snapshot_interval:
+                snapshot = self._create_snapshot(products)
+                # 插入快照到正确位置，保持时间倒序
+                insert_position = self._find_insert_position_for_snapshot(data['transactions'], snapshot)
+                data['transactions'].insert(insert_position, snapshot)
+                snapshot_count = 0
+        
+        # 更新最终产品状态
+        data['products'] = products
+        
+        return total_records
+    
+    def _calculate_outbound_price_from_products(self, products, product_name, outbound_date):
+        """基于当前产品状态计算出库价格"""
+        if product_name in products:
+            return products[product_name].get('avg_price', '0.00000000')
+        return '0.00000000'
+    
+    def _update_product_inventory(self, products, txn):
+        """更新产品库存"""
+        product_name = txn['product']
+        
+        if product_name not in products:
+            products[product_name] = {
+                'total_weight': '0.00000000',
+                'avg_price': '0.00000000'
+            }
+        
+        if txn['type'] == '入库':
+            self._update_average_price(
+                products[product_name],
+                txn['weight'],
+                txn['price']
+            )
+        elif txn['type'] == '出库':
+            current_weight = Decimal(products[product_name]['total_weight'])
+            out_weight = Decimal(txn['weight'])
+            if current_weight < out_weight:
+                # 库存不足，返回错误指示
+                return False
+            new_weight = current_weight - out_weight
+            products[product_name]['total_weight'] = f"{new_weight:.8f}"
+            return True
+        return True
+    
+    def _update_average_price(self, product, weight, price):
+        """更新产品加权平均价格"""
+        total_weight = Decimal(product['total_weight'])
+        avg_price = Decimal(product['avg_price'])
+        
+        new_weight = Decimal(weight)
+        new_price = Decimal(price)
+        
+        if total_weight > 0:
+            new_total = total_weight + new_weight
+            new_avg = (total_weight * avg_price + new_weight * new_price) / new_total
+        else:
+            new_total = new_weight
+            new_avg = new_price
+        
+        product['total_weight'] = f"{new_total:.8f}"
+        product['avg_price'] = f"{new_avg:.8f}"
+    
+    def _create_snapshot(self, products):
+        """创建快照"""
+        return {
+            "is_snapshot": True,
+            "timestamp": datetime.now().strftime('%Y-%m-%d'),
+            "daily_sequence": 0,
+            "products": copy.deepcopy(products)
+        }
+    
+    def _find_insert_position_for_snapshot(self, transactions, snapshot):
+        """找到快照的正确插入位置，保持时间倒序"""
+        snapshot_time = snapshot['timestamp']
+        
+        for i, txn in enumerate(transactions):
+            txn_time = txn.get('time', txn.get('timestamp', ''))
+            if txn_time < snapshot_time:
+                return i
+        
+        return len(transactions)
+    
+    def _get_next_sequence(self, timestamp):
+        """获取当日下一个序列号"""
+        try:
+            with open(self.data_path, 'r', encoding='utf-8') as f:
+                data = json.load(f)
+            
+            max_seq = 0
+            for txn in data['transactions']:
+                if txn.get('time') == timestamp and not txn.get('is_snapshot'):
+                    max_seq = max(max_seq, txn.get('daily_sequence', 0))
+            
+            return max_seq + 1
+        except:
+            return 1
+    
+    def calculate_outbound_price(self, product_name, outbound_date):
+        """计算出库价格：基于最近且日期较早的快照，然后按时间顺序用后续入库记录进行加权平均"""
+        try:
+            with open(self.data_path, 'r', encoding='utf-8') as f:
+                data = json.load(f)
+            
+            # 找到基准快照
+            base_snapshot = self._find_base_snapshot(outbound_date, data['transactions'])
+            
+            # 初始化产品状态 - 确保快照中不存在的产品重量和价格设置为0
+            snapshot_products = base_snapshot.get('products', {})
+            if product_name in snapshot_products:
+                product_data = snapshot_products[product_name]
+                current_weight = Decimal(product_data.get('total_weight', '0.00000000'))
+                current_avg_price = Decimal(product_data.get('avg_price', '0.00000000'))
+            else:
+                # 快照中不存在该产品，设置为0
+                current_weight = Decimal('0.00000000')
+                current_avg_price = Decimal('0.00000000')
+            
+            # 收集快照之后的所有相关交易（入库和出库）
+            base_timestamp = base_snapshot.get('timestamp', '1900-01-01')
+            relevant_transactions = []
+            for txn in data['transactions']:
+                if (not txn.get('is_snapshot') and 
+                    txn.get('product') == product_name and
+                    txn.get('time', '') >= base_timestamp and
+                    txn.get('time', '') <= outbound_date):
+                    relevant_transactions.append(txn)
+            
+            # 按时间正序排序，确保加权平均计算正确
+            relevant_transactions.sort(key=lambda x: (x.get('time', ''), x.get('daily_sequence', 0)))
+            
+            # 依次进行加权平均计算，考虑入库和出库
+            for record in relevant_transactions:
+                if record['type'] == '入库':
+                    record_weight = Decimal(record['weight'])
+                    record_price = Decimal(record['price'])
+                    
+                    if current_weight > 0:
+                        new_total_weight = current_weight + record_weight
+                        current_avg_price = (current_weight * current_avg_price + record_weight * record_price) / new_total_weight
+                        current_weight = new_total_weight
+                    else:
+                        current_avg_price = record_price
+                        current_weight = record_weight
+                elif record['type'] == '出库':
+                    out_weight = Decimal(record['weight'])
+                    current_weight -= out_weight
+                    # 如果出库导致库存为负，理论上不应该发生，但为了健壮性，可以将其设为0
+                    if current_weight < 0:
+                        current_weight = Decimal('0.00000000')
+                        current_avg_price = Decimal('0.00000000')
+            
+            return f"{current_avg_price:.8f}"
+            
+        except Exception as e:
+            return '0.00000000'
+    
+    def get_product_list(self):
+        """获取产品列表（流式读取）"""
+        try:
+            with open(self.data_path, 'r', encoding='utf-8') as f:
+                data = json.load(f)
+            return data.get('products', {})
+        except:
+            return {}
+    
+    def initialize_data_file(self):
+        """初始化数据文件"""
+        # 创建初始空快照
+        initial_snapshot = {
+            "is_snapshot": True,
+            "timestamp": "1900-01-01",
+            "daily_sequence": 0,
+            "products": {}
+        }
+        
+        initial_data = {
+            "$schema": "./inventory_schema.json",
+            "products": {},
+            "transactions": [initial_snapshot]
+        }
+        
+        try:
+            with open(self.data_path, 'w', encoding='utf-8') as f:
+                json.dump(initial_data, f, indent=2, ensure_ascii=False)
+        except Exception as e:
+            raise Exception(f"初始化数据文件失败: {str(e)}")
+
+if __name__ == '__main__':
+    manager = InventoryManager('inventory_data.json')
+    # 测试代码
+    test_txn = {
+        'product': 'TEST001',
+        'type': '入库',
+        'weight': '100.00000000',
+        'price': '10.00000000',
+        'note': '测试入库',
+        'time': '2025-01-15'
+    }
+    result = manager.process_transaction(test_txn)
+    print(result)
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