from uuid import UUID

from fastapi import APIRouter, Depends, HTTPException
from sqlalchemy import delete, select
from sqlalchemy.orm import Session
from sqlalchemy.sql import func

from app.api import deps
from app.api.utils import update_object_from_payload, verify_id_list
from app.models import Project, Slot, User, Volunteer, association_table_volunteer_slot
from app.schemas.requests import VolunteerCreateRequest, VolunteerUpdateRequest
from app.schemas.responses import VolunteerResponse

router = APIRouter()


@router.get("/project/{project_id}/volunteers", response_model=list[VolunteerResponse])
async def list_project_volunteers(
    project_id: UUID,
    current_user: User = Depends(deps.get_current_user),
    session: Session = Depends(deps.get_session),
):
    """List volunteers from project"""
    p = session.get(Project, project_id)
    if p is None:
        raise HTTPException(status_code=404, detail="Project not found")

    results = session.execute(select(Volunteer).where(Volunteer.project_id == project_id))
    return results.scalars().all()


@router.post("/project/{project_id}/volunteer", response_model=VolunteerResponse)
async def create_volunteer(
    project_id: UUID,
    new_volunteer: VolunteerCreateRequest,
    current_user: User = Depends(deps.get_current_user),
    session: Session = Depends(deps.get_session),
):
    """Create a new volunteer to the project"""
    p = session.get(Project, project_id)
    if p is None:
        raise HTTPException(status_code=404, detail="Project not found")
    input_dict = new_volunteer.model_dump()

    # Extract slots list from input dict
    slots: list[UUID] = []
    if input_dict["slots"] is not None:
        slots = input_dict["slots"]
        await verify_id_list(session, slots, project_id, Slot, "Invalid slot list")
    del input_dict["slots"]

    volunteer = Volunteer(project_id=project_id, **input_dict)
    session.add(volunteer)
    # commit to optain an id for the volunteer
    session.commit()

    if len(slots) > 0:
        session.execute(
            association_table_volunteer_slot.insert().values(
                [(volunteer.id, slot_id) for slot_id in slots]
            )
        )
    session.commit()
    return volunteer


@router.post("/project/{project_id}/volunteer/{volunteer_id}", response_model=VolunteerResponse)
async def update_volunteer(
    project_id: UUID,
    volunteer_id: UUID,
    new_volunteer: VolunteerUpdateRequest,
    current_user: User = Depends(deps.get_current_user),
    session: Session = Depends(deps.get_session),
):
    """Update a volunteer from the project"""
    volunteer = session.get(Volunteer, volunteer_id)
    if (volunteer is None) or (volunteer.project_id != str(project_id)):
        raise HTTPException(status_code=404, detail="Volunteer not found")

    input_dict = new_volunteer.model_dump(exclude_unset=True)
    # Extract slots list from input dict
    if "slots" in input_dict:
        slots: list[UUID] = input_dict["slots"]
        await verify_id_list(session, slots, project_id, Slot, "Invalid slot list")
        # Remove previous values
        session.execute(
            association_table_volunteer_slot.delete().where(
                association_table_volunteer_slot.c.volunteer_id == volunteer.id
            )
        )
        # Add the new slots
        if len(slots) > 0:
            session.execute(
                association_table_volunteer_slot.insert().values(
                    [(volunteer.id, slot_id) for slot_id in slots]
                )
            )
        del input_dict["slots"]

    update_object_from_payload(volunteer, input_dict)
    session.commit()
    session.refresh(volunteer)
    return volunteer


@router.delete("/project/{project_id}/volunteer/{volunteer_id}")
async def delete_volunteer(
    project_id: UUID,
    volunteer_id: UUID,
    current_user: User = Depends(deps.get_current_user),
    session: Session = Depends(deps.get_session),
):
    """Delete a volunteer from the project"""
    session.execute(
        delete(Volunteer).where(
            (Volunteer.id == volunteer_id) & (Volunteer.project_id == project_id)
        )
    )
    session.commit()