"""
Bill Notes API — private per-user notes on individual bills.
One note per (user, bill). PUT upserts, DELETE removes.
"""
from fastapi import APIRouter, Depends, HTTPException
from sqlalchemy import select
from sqlalchemy.ext.asyncio import AsyncSession

from app.core.dependencies import get_current_user
from app.database import get_db
from app.models.bill import Bill
from app.models.note import BillNote
from app.models.user import User
from app.schemas.schemas import BillNoteSchema, BillNoteUpsert

router = APIRouter()


@router.get("/{bill_id}", response_model=BillNoteSchema)
async def get_note(
    bill_id: str,
    current_user: User = Depends(get_current_user),
    db: AsyncSession = Depends(get_db),
):
    result = await db.execute(
        select(BillNote).where(
            BillNote.user_id == current_user.id,
            BillNote.bill_id == bill_id,
        )
    )
    note = result.scalar_one_or_none()
    if not note:
        raise HTTPException(status_code=404, detail="No note for this bill")
    return note


@router.put("/{bill_id}", response_model=BillNoteSchema)
async def upsert_note(
    bill_id: str,
    body: BillNoteUpsert,
    current_user: User = Depends(get_current_user),
    db: AsyncSession = Depends(get_db),
):
    bill = await db.get(Bill, bill_id)
    if not bill:
        raise HTTPException(status_code=404, detail="Bill not found")

    result = await db.execute(
        select(BillNote).where(
            BillNote.user_id == current_user.id,
            BillNote.bill_id == bill_id,
        )
    )
    note = result.scalar_one_or_none()

    if note:
        note.content = body.content
        note.pinned = body.pinned
    else:
        note = BillNote(
            user_id=current_user.id,
            bill_id=bill_id,
            content=body.content,
            pinned=body.pinned,
        )
        db.add(note)

    await db.commit()
    await db.refresh(note)
    return note


@router.delete("/{bill_id}", status_code=204)
async def delete_note(
    bill_id: str,
    current_user: User = Depends(get_current_user),
    db: AsyncSession = Depends(get_db),
):
    result = await db.execute(
        select(BillNote).where(
            BillNote.user_id == current_user.id,
            BillNote.bill_id == bill_id,
        )
    )
    note = result.scalar_one_or_none()
    if not note:
        raise HTTPException(status_code=404, detail="No note for this bill")
    await db.delete(note)
    await db.commit()