from fastapi import HTTPException
from sqlalchemy.ext.asyncio import AsyncSession
from sqlalchemy.orm import selectinload
from sqlmodel import select

from job.candidate.models import Notes
from job.notes.serializers import serialize_note


class Note:
    def __init__(self,session:AsyncSession):
        self.session=session

    async def _load(self,record_id):
        uid=Notes._as_uuid(record_id)
        if uid is None:
            return None
        result=await self.session.execute(
            select(Notes).options(selectinload(Notes.author)).where(Notes.id==uid)
        )
        return result.scalars().first()

    async def get_note(self,note_id=None,user_id=None):
        if note_id:
            row=await self._load(note_id)
            if not row:
                raise HTTPException(status_code=404,detail="Note not found")
            return serialize_note(row)
        if not user_id:
            raise HTTPException(status_code=400,detail="note_id or user_id is required")
        uid=Notes._as_uuid(user_id)
        if uid is None:
            raise HTTPException(status_code=400,detail="Invalid user_id")
        result=await self.session.execute(
            select(Notes)
            .options(selectinload(Notes.author))
            .where(Notes.user_id==uid)
            .order_by(Notes.created_at.desc())
        )
        return [serialize_note(r) for r in result.scalars().all()]

    async def create_note(self,payload,current_user):
        fields={
            "note":payload.get("note") or "",
            "user_id":payload.get("user_id"),
            "created_by":current_user.get("id") if isinstance(current_user,dict) else None,
        }
        if not fields["user_id"]:
            raise HTTPException(status_code=400,detail="user_id is required")
        row=await Notes.insert_note(self.session,fields)
        row=await self._load(row.id)
        return serialize_note(row)

    async def update_note(self,note_id,payload):
        fields={k:v for k,v in payload.items() if v is not None and k in ("note",)}
        if not fields:
            raise HTTPException(status_code=400,detail="No fields to update")
        row=await Notes.update_note(self.session,note_id,fields)
        if not row:
            raise HTTPException(status_code=404,detail="Note not found")
        row=await self._load(row.id)
        return serialize_note(row)