import uuid
from typing import Any

from fastapi import APIRouter, Depends, HTTPException
from sqlmodel import col, delete, func, select

from app import crud
from app.api.deps import (
    CurrentUser,
    SessionDep,
    get_current_active_superuser,
)
from app.core.config import settings
from app.core.security import get_password_hash, verify_password
from app.models import (
    Item,
    Message,
    UpdatePassword,
    User,
    UserCreate,
    UserPublic,
    UserRegister,
    UsersPublic,
    UserUpdate,
    UserUpdateMe,
)
from app.utils import generate_new_account_email, send_email

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


@router.get(
    "/",
    dependencies=[Depends(get_current_active_superuser)],
    response_model=UsersPublic,
)
def read_users(session: SessionDep, skip: int = 0, limit: int = 100) -> Any:
    """
    获取用户列表。
    """

    count_statement = select(func.count()).select_from(User)
    count = session.exec(count_statement).one()

    statement = select(User).offset(skip).limit(limit)
    users = session.exec(statement).all()

    return UsersPublic(data=users, count=count)


@router.post(
    "/", dependencies=[Depends(get_current_active_superuser)], response_model=UserPublic
)
def create_user(*, session: SessionDep, user_in: UserCreate) -> Any:
    """
    创建新用户。
    """
    user = crud.get_user_by_email(session=session, email=user_in.email)
    if user:
        raise HTTPException(
            status_code=400,
            detail="系统中已存在该邮箱的用户。",
        )

    user = crud.create_user(session=session, user_create=user_in)
    if settings.emails_enabled and user_in.email:
        email_data = generate_new_account_email(
            email_to=user_in.email, username=user_in.email, password=user_in.password
        )
        send_email(
            email_to=user_in.email,
            subject=email_data.subject,
            html_content=email_data.html_content,
        )
    return user


@router.patch("/me", response_model=UserPublic)
def update_user_me(
    *, session: SessionDep, user_in: UserUpdateMe, current_user: CurrentUser
) -> Any:
    """
    更新当前用户信息。
    """

    if user_in.email:
        existing_user = crud.get_user_by_email(session=session, email=user_in.email)
        if existing_user and existing_user.id != current_user.id:
            raise HTTPException(
                status_code=409, detail="该邮箱已被其他用户使用"
            )
    user_data = user_in.model_dump(exclude_unset=True)
    current_user.sqlmodel_update(user_data)
    session.add(current_user)
    session.commit()
    session.refresh(current_user)
    return current_user


@router.patch("/me/password", response_model=Message)
def update_password_me(
    *, session: SessionDep, body: UpdatePassword, current_user: CurrentUser
) -> Any:
    """
    更新当前用户密码。
    """
    if not verify_password(body.current_password, current_user.hashed_password):
        raise HTTPException(status_code=400, detail="密码错误")
    if body.current_password == body.new_password:
        raise HTTPException(
            status_code=400, detail="新密码不能与当前密码相同"
        )
    hashed_password = get_password_hash(body.new_password)
    current_user.hashed_password = hashed_password
    session.add(current_user)
    session.commit()
    return Message(message="密码更新成功")


@router.get("/me", response_model=UserPublic)
def read_user_me(current_user: CurrentUser) -> Any:
    """
    获取当前用户信息。
    """
    return current_user


@router.delete("/me", response_model=Message)
def delete_user_me(session: SessionDep, current_user: CurrentUser) -> Any:
    """
    删除当前用户。
    """
    if current_user.is_superuser:
        raise HTTPException(
            status_code=403, detail="超级用户不允许删除自己"
        )
    session.delete(current_user)
    session.commit()
    return Message(message="用户删除成功")


@router.post("/signup", response_model=UserPublic)
def register_user(session: SessionDep, user_in: UserRegister) -> Any:
    """
    无需登录即可创建新用户（用户注册）。
    """
    user = crud.get_user_by_email(session=session, email=user_in.email)
    if user:
        raise HTTPException(
            status_code=400,
            detail="系统中已存在该邮箱的用户",
        )
    user_create = UserCreate.model_validate(user_in)
    user = crud.create_user(session=session, user_create=user_create)
    return user


@router.get("/{user_id}", response_model=UserPublic)
def read_user_by_id(
    user_id: uuid.UUID, session: SessionDep, current_user: CurrentUser
) -> Any:
    """
    通过 ID 获取指定用户。
    """
    user = session.get(User, user_id)
    if user == current_user:
        return user
    if not current_user.is_superuser:
        raise HTTPException(
            status_code=403,
            detail="用户权限不足",
        )
    return user


@router.patch(
    "/{user_id}",
    dependencies=[Depends(get_current_active_superuser)],
    response_model=UserPublic,
)
def update_user(
    *,
    session: SessionDep,
    user_id: uuid.UUID,
    user_in: UserUpdate,
) -> Any:
    """
    更新用户信息。
    """

    db_user = session.get(User, user_id)
    if not db_user:
        raise HTTPException(
            status_code=404,
            detail="系统中不存在该ID的用户",
        )
    if user_in.email:
        existing_user = crud.get_user_by_email(session=session, email=user_in.email)
        if existing_user and existing_user.id != user_id:
            raise HTTPException(
                status_code=409, detail="该邮箱已被其他用户使用"
            )

    db_user = crud.update_user(session=session, db_user=db_user, user_in=user_in)
    return db_user


@router.delete("/{user_id}", dependencies=[Depends(get_current_active_superuser)])
def delete_user(
    session: SessionDep, current_user: CurrentUser, user_id: uuid.UUID
) -> Message:
    """
    删除用户。
    """
    user = session.get(User, user_id)
    if not user:
        raise HTTPException(status_code=404, detail="用户未找到")
    if user == current_user:
        raise HTTPException(
            status_code=403, detail="超级用户不允许删除自己"
        )
    statement = delete(Item).where(col(Item.owner_id) == user_id)
    session.exec(statement)  # type: ignore
    session.delete(user)
    session.commit()
    return Message(message="用户删除成功")