from datetime import datetime
from typing import Optional
from sqlalchemy import Column, Integer, String, Float, DateTime, ForeignKey, Enum
from sqlalchemy.sql import func
from pydantic import BaseModel, Field
from .database import Base
import enum

class CouponStatus(str, enum.Enum):
    UNUSED = "UNUSED"
    USED = "USED"
    EXPIRED = "EXPIRED"

class CouponType(str, enum.Enum):
    PRODUCT = "PRODUCT" # 商品
    CASH = "CASH" # 现金

# 数据库模型
class CouponDB(Base):
    __tablename__ = "coupons"

    id = Column(Integer, primary_key=True, autoincrement=True)
    name = Column(String(100), nullable=False)
    amount = Column(Float, nullable=False)
    coupon_type = Column(Enum(CouponType), nullable=False, default=CouponType.CASH)
    create_time = Column(DateTime(timezone=True), server_default=func.now())
    update_time = Column(DateTime(timezone=True), onupdate=func.now())

class UserCouponDB(Base):
    __tablename__ = "user_coupons"

    id = Column(Integer, primary_key=True, autoincrement=True)
    user_id = Column(Integer, ForeignKey("users.userid"), index=True)
    coupon_id = Column(Integer, ForeignKey("coupons.id"), index=True)
    coupon_name = Column(String(100), nullable=False)
    coupon_type = Column(Enum(CouponType), nullable=False)
    coupon_amount = Column(Float, nullable=False)
    expire_time = Column(DateTime(timezone=True), nullable=False)
    used_time = Column(DateTime(timezone=True), nullable=True)
    status = Column(Enum(CouponStatus), default=CouponStatus.UNUSED)
    create_time = Column(DateTime(timezone=True), server_default=func.now())
    update_time = Column(DateTime(timezone=True), onupdate=func.now())

# Pydantic 模型
class CouponCreate(BaseModel):
    name: str = Field(..., max_length=100)
    amount: Optional[float] = Field(None)
    coupon_type: CouponType = Field(CouponType.CASH)

class CouponUpdate(BaseModel):
    name: Optional[str] = Field(None, max_length=100)
    amount: Optional[float] = Field(None)
    coupon_type: CouponType = Field(CouponType.CASH)

class CouponInfo(BaseModel):
    id: int
    name: str
    amount: float
    coupon_type: CouponType
    create_time: datetime
    
    class Config:
        from_attributes = True

class UserCouponCreate(BaseModel):
    user_id: int
    coupon_id: int
    expire_time: datetime
    count: int = Field(..., gt=0, description="发放数量")

class UserCouponInfo(BaseModel):
    id: int
    user_id: int
    coupon_id: int
    coupon_name: str
    coupon_amount: float
    coupon_type: CouponType
    expire_time: datetime
    used_time: Optional[datetime] = None
    status: CouponStatus
    create_time: datetime
    
    class Config:
        from_attributes = True