import enum
from uuid import uuid4

from sqlalchemy import JSON, Column, DateTime, Enum, Float, ForeignKey, Integer, String, Text
from sqlalchemy.orm import relationship
from sqlalchemy.sql import func

from app.core.database import Base


class OrderStatus(enum.Enum):
    PENDING = "pending"
    PROCESSING = "processing"
    SHIPPED = "shipped"
    DELIVERED = "delivered"
    CANCELLED = "cancelled"
    REFUNDED = "refunded"

class ShippingMethod(enum.Enum):
    STANDARD = "standard"
    EXPRESS = "express"
    OVERNIGHT = "overnight"
    PICKUP = "pickup"
    DIGITAL = "digital"

class Order(Base):
    __tablename__ = "orders"

    id = Column(String(36), primary_key=True, default=lambda: str(uuid4()))
    user_id = Column(String(36), ForeignKey("users.id"), nullable=False)
    order_number = Column(String(50), nullable=False, unique=True, index=True)
    status = Column(Enum(OrderStatus), default=OrderStatus.PENDING)
    total_amount = Column(Float, nullable=False)
    subtotal = Column(Float, nullable=False)
    tax_amount = Column(Float, nullable=False)
    shipping_amount = Column(Float, nullable=False)
    discount_amount = Column(Float, default=0.0)
    shipping_method = Column(Enum(ShippingMethod), nullable=True)
    tracking_number = Column(String(100), nullable=True)
    notes = Column(Text, nullable=True)
    shipping_address = Column(JSON, nullable=True)  # JSON containing shipping address
    billing_address = Column(JSON, nullable=True)  # JSON containing billing address
    created_at = Column(DateTime(timezone=True), server_default=func.now())
    updated_at = Column(DateTime(timezone=True), onupdate=func.now())

    # Relationships
    user = relationship("User", back_populates="orders")
    items = relationship("OrderItem", back_populates="order", cascade="all, delete-orphan")
    payments = relationship("Payment", back_populates="order", cascade="all, delete-orphan")

    def __repr__(self):
        return f"<Order {self.order_number}>"

class OrderItem(Base):
    __tablename__ = "order_items"

    id = Column(String(36), primary_key=True, default=lambda: str(uuid4()))
    order_id = Column(String(36), ForeignKey("orders.id", ondelete="CASCADE"), nullable=False)
    product_id = Column(String(36), ForeignKey("products.id"), nullable=False)
    quantity = Column(Integer, default=1, nullable=False)
    unit_price = Column(Float, nullable=False)  # Price at the time of purchase
    subtotal = Column(Float, nullable=False)  # unit_price * quantity
    discount = Column(Float, default=0.0)
    tax_amount = Column(Float, default=0.0)
    product_name = Column(String(255), nullable=False)  # Store name in case product is deleted
    product_sku = Column(String(100), nullable=True)
    product_options = Column(JSON, nullable=True)  # JSON containing selected options
    created_at = Column(DateTime(timezone=True), server_default=func.now())

    # Relationships
    order = relationship("Order", back_populates="items")
    product = relationship("Product", back_populates="order_items")

    def __repr__(self):
        return f"<OrderItem {self.id} for Order {self.order_id}>"