from datetime import datetime
from typing import Annotated, Literal

from pydantic import BaseModel, ConfigDict, EmailStr, Field, SecretStr, field_validator

Password = Annotated[SecretStr, Field(min_length=15, max_length=128)]


class AuthInput(BaseModel):
    model_config = ConfigDict(extra="forbid")


class ProfileInput(AuthInput):
    nickname: str | None = Field(None, min_length=1, max_length=80)
    email: EmailStr | None = Field(None, max_length=254)

    @field_validator("nickname", "email", mode="before")
    @classmethod
    def optional_text(cls, value):
        return (value.strip() or None) if isinstance(value, str) else value

    @field_validator("nickname")
    @classmethod
    def no_control_characters(cls, value):
        if value and any(ord(char) < 32 or ord(char) == 127 for char in value):
            raise ValueError("昵称不能包含控制字符")
        return value


class RegisterInput(ProfileInput):
    username: str = Field(min_length=3, max_length=32, pattern=r"^[a-z][a-z0-9_]{2,31}$")
    password: Password

    @field_validator("username", mode="before")
    @classmethod
    def canonical_username(cls, value):
        return value.strip().lower() if isinstance(value, str) else value


class LoginInput(AuthInput):
    username: str = Field(min_length=3, max_length=32, pattern=r"^[a-z][a-z0-9_]{2,31}$")
    password: SecretStr = Field(min_length=1, max_length=128)

    @field_validator("username", mode="before")
    @classmethod
    def canonical_username(cls, value):
        return value.strip().lower() if isinstance(value, str) else value


class PasswordChangeInput(AuthInput):
    current_password: SecretStr = Field(min_length=1, max_length=128)
    new_password: Password


class UserRead(BaseModel):
    model_config = ConfigDict(from_attributes=True)

    id: int
    username: str
    nickname: str | None
    email: str | None
    role: Literal["user", "admin"]
    created_at: datetime


class SessionRead(UserRead):
    csrf_token: str