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
from sqlalchemy.orm import relationship

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())

class CouponIssueRecordDB(Base):
    """优惠券发放记录表"""
    __tablename__ = "coupon_issue_records"

    id = Column(Integer, primary_key=True, autoincrement=True)
    coupon_id = Column(Integer, ForeignKey("coupons.id"), nullable=False)
    user_id = Column(Integer, ForeignKey("users.userid"), nullable=False)
    operator_id = Column(Integer, ForeignKey("users.userid"), nullable=False)  # 操作人ID
    count = Column(Integer, nullable=False, default=1)  # 发放数量
    issue_time = Column(DateTime(timezone=True), nullable=False, server_default=func.now())
    remark = Column(String(200), nullable=True)  # 备注信息
    
    # 关联关系
    coupon = relationship("CouponDB", backref="issue_records")
    user = relationship("UserDB", foreign_keys=[user_id], backref="received_coupon_records")
    operator = relationship("UserDB", foreign_keys=[operator_id], backref="operated_coupon_records")

# 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
    remark: Optional[str] = None
    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

class CouponIssueRecordCreate(BaseModel):
    coupon_id: int
    user_id: int
    count: int = 1
    remark: Optional[str] = None

class CouponIssueRecordInfo(BaseModel):
    id: int
    coupon_id: int
    user_id: int
    operator_id: int
    count: int
    issue_time: datetime
    remark: Optional[str] = None
    coupon_name: Optional[str] = None
    user_nickname: Optional[str] = None
    operator_nickname: Optional[str] = None
    
    class Config:
        from_attributes = True