from __future__ import annotations

from typing import Annotated

from fastapi import APIRouter, Depends, HTTPException, status
from pydantic import BaseModel, Field

from ..config import Settings, get_settings
from ..credentials import get_credentials, update_credentials
from .auth import LoginRequest, LoginResponse, issue_token, require_user

router = APIRouter(prefix="/api/auth", tags=["auth"])


class ChangeCredentialsRequest(BaseModel):
    current_password: str = Field(min_length=1)
    new_username: str = Field(min_length=1, max_length=64)
    new_password: str = Field(min_length=4, max_length=128)


@router.post("/login", response_model=LoginResponse)
async def login(body: LoginRequest, settings: Annotated[Settings, Depends(get_settings)]) -> LoginResponse:
    user, pwd = get_credentials()
    if body.username != user or body.password != pwd:
        raise HTTPException(status_code=status.HTTP_401_UNAUTHORIZED, detail="用户名或密码错误")
    token, ttl = issue_token(body.username, settings)
    return LoginResponse(
        token=token,
        username=body.username,
        expires_in=ttl,
        env_name=settings.env_name,
        mode=settings.mode,
    )


@router.get("/me")
async def me(username: Annotated[str, Depends(require_user)], settings: Annotated[Settings, Depends(get_settings)]) -> dict:
    return {
        "username": username,
        "env_name": settings.env_name,
        "mode": settings.mode,
        "sim": settings.is_sim,
    }


@router.post("/change-credentials", response_model=LoginResponse)
async def change_credentials(
    body: ChangeCredentialsRequest,
    username: Annotated[str, Depends(require_user)],
    settings: Annotated[Settings, Depends(get_settings)],
) -> LoginResponse:
    _cur_user, cur_pwd = get_credentials()
    if body.current_password != cur_pwd:
        raise HTTPException(status_code=status.HTTP_400_BAD_REQUEST, detail="当前密码不正确")
    try:
        update_credentials(new_username=body.new_username, new_password=body.new_password)
    except ValueError as e:
        raise HTTPException(status_code=status.HTTP_400_BAD_REQUEST, detail=str(e)) from e
    token, ttl = issue_token(body.new_username.strip(), settings)
    return LoginResponse(
        token=token,
        username=body.new_username.strip(),
        expires_in=ttl,
        env_name=settings.env_name,
        mode=settings.mode,
    )