order.py

from datetime import datetime

class Order:
    """Represents a purchase order for inventory restocking"""
    
    # Class variable for generating unique order IDs
    _order_counter = 1000
    
    def __init__(self, product_id, quantity, priority=5, supplier_id=None):
        """
        Initialize an Order
        
        Args:
            product_id (str): ID of the product to order
            quantity (int): Quantity to order
            priority (int): Priority level (1-10, where 1 is highest priority)
            supplier_id (str): ID of the supplier (optional)
        """
        Order._order_counter += 1
        self._order_id = f"ORD{Order._order_counter}"
        self._product_id = product_id
        self._quantity = quantity
        self._priority = priority
        self._supplier_id = supplier_id
        self._status = "Pending"  # Pending, Approved, Shipped, Received, Cancelled
        self._order_date = datetime.now()
        self._received_date = None
    
    # Getters
    @property
    def order_id(self):
        return self._order_id
    
    @property
    def product_id(self):
        return self._product_id
    
    @property
    def quantity(self):
        return self._quantity
    
    @property
    def priority(self):
        return self._priority
    
    @property
    def supplier_id(self):
        return self._supplier_id
    
    @property
    def status(self):
        return self._status
    
    @property
    def order_date(self):
        return self._order_date
    
    @property
    def received_date(self):
        return self._received_date
    
    # Setters
    @quantity.setter
    def quantity(self, value):
        if value <= 0:
            raise ValueError("Quantity must be positive")
        self._quantity = value
    
    @priority.setter
    def priority(self, value):
        if not (1 <= value <= 10):
            raise ValueError("Priority must be between 1 and 10")
        self._priority = value
    
    @status.setter
    def status(self, value):
        valid_statuses = ["Pending", "Approved", "Shipped", "Received", "Cancelled"]
        if value not in valid_statuses:
            raise ValueError(f"Status must be one of {valid_statuses}")
        self._status = value
        if value == "Received":
            self._received_date = datetime.now()
    
    def __lt__(self, other):
        """Less than comparison for priority queue (lower priority number = higher priority)"""
        if self._priority != other._priority:
            return self._priority < other._priority
        return self._order_date < other._order_date
    
    def __le__(self, other):
        """Less than or equal comparison"""
        return self.__lt__(other) or self.__eq__(other)
    
    def __gt__(self, other):
        """Greater than comparison"""
        return not self.__le__(other)
    
    def __ge__(self, other):
        """Greater than or equal comparison"""
        return not self.__lt__(other)
    
    def __eq__(self, other):
        """Equality comparison"""
        return self._order_id == other._order_id
    
    def __str__(self):
        return f"Order({self._order_id}, Product: {self._product_id}, Qty: {self._quantity}, Priority: {self._priority}, Status: {self._status})"
    
    def __repr__(self):
        return self.__str__()
    
    def to_dict(self):
        """Convert order to dictionary"""
        return {
            'order_id': self._order_id,
            'product_id': self._product_id,
            'quantity': self._quantity,
            'priority': self._priority,
            'supplier_id': self._supplier_id,
            'status': self._status,
            'order_date': self._order_date.strftime('%Y-%m-%d %H:%M:%S'),
            'received_date': self._received_date.strftime('%Y-%m-%d %H:%M:%S') if self._received_date else None
        }