"""User schemas for request and response validation.

This module defines Pydantic schemas for user-related operations including
registration, authentication, and user information retrieval.
"""

from datetime import datetime
from typing import Optional
from uuid import UUID

from pydantic import BaseModel, EmailStr, Field


class UserBase(BaseModel):
    """Base user schema with common attributes."""
    
    email: EmailStr = Field(description="User's email address")
    is_active: bool = Field(default=True, description="Whether account is active")
    is_superuser: bool = Field(default=False, description="Whether user is admin")


class UserCreate(BaseModel):
    """Schema for user registration.
    
    Attributes:
        email: User's email address (must be unique)
        password: Plain text password (will be hashed)
    """
    
    email: EmailStr = Field(description="User's email address")
    password: str = Field(
        min_length=8,
        description="User's password (minimum 8 characters)",
    )


class UserUpdate(BaseModel):
    """Schema for user updates.
    
    All fields are optional to allow partial updates.
    """
    
    email: Optional[EmailStr] = Field(default=None, description="New email address")
    password: Optional[str] = Field(
        default=None,
        min_length=8,
        description="New password (minimum 8 characters)",
    )
    is_active: Optional[bool] = Field(default=None, description="Account status")


class UserInDB(UserBase):
    """Schema representing user as stored in database.
    
    Includes the hashed password - should never be returned in API responses.
    """
    
    id: UUID
    hashed_password: str = Field(description="Bcrypt hashed password")
    created_at: datetime
    updated_at: datetime
    
    class Config:
        from_attributes = True


class UserPublic(UserBase):
    """Schema for user information returned in API responses.
    
    Excludes sensitive fields like hashed_password.
    """
    
    id: UUID
    created_at: datetime
    
    class Config:
        from_attributes = True


class Token(BaseModel):
    """Schema for authentication token response."""
    
    access_token: str = Field(description="JWT access token")
    token_type: str = Field(default="bearer", description="Token type")


class TokenPayload(BaseModel):
    """Schema for JWT token payload."""
    
    sub: Optional[str] = Field(default=None, description="Subject (user ID)")
    exp: Optional[datetime] = Field(default=None, description="Expiration time")
    type: Optional[str] = Field(default=None, description="Token type")