from __future__ import annotations

from app.database import Relationship, User
from app.database.relationship import RelationshipType
from app.dependencies.database import get_db
from app.dependencies.user import get_client_user

from .router import router

from fastapi import Depends, HTTPException, Path, Security
from pydantic import BaseModel, Field
from sqlmodel import select
from sqlmodel.ext.asyncio.session import AsyncSession


class CheckResponse(BaseModel):
    is_followed: bool = Field(..., description="对方是否关注了当前用户")
    is_following: bool = Field(..., description="当前用户是否关注了对方")
    mutual: bool = Field(..., description="当前用户与对方是否互相关注")


@router.get(
    "/relationship/check/{user_id}",
    name="检查关系状态",
    description="检查当前用户与指定用户的关系状态",
    response_model=CheckResponse,
)
async def check_user_relationship(
    user_id: int = Path(..., description="目标用户的 ID"),
    current_user: User = Security(get_client_user),
    db: AsyncSession = Depends(get_db),
):
    if user_id == current_user.id:
        raise HTTPException(422, "Cannot check relationship with yourself")

    my_relationship = (
        await db.exec(
            select(Relationship).where(
                Relationship.user_id == current_user.id,
                Relationship.target_id == user_id,
            )
        )
    ).first()

    target_relationship = (
        await db.exec(
            select(Relationship).where(
                Relationship.user_id == user_id,
                Relationship.target_id == current_user.id,
            )
        )
    ).first()

    is_followed = bool(
        target_relationship and target_relationship.type == RelationshipType.FOLLOW
    )
    is_following = bool(
        my_relationship and my_relationship.type == RelationshipType.FOLLOW
    )

    return CheckResponse(
        is_followed=is_followed,
        is_following=is_following,
        mutual=is_followed and is_following,
    )