from calendar import monthrange
from datetime import date, datetime

from fastapi import APIRouter, Body, Depends, HTTPException, Security, status
from sqlalchemy import or_
from sqlalchemy.orm import Session

from ..core.security import get_current_active_user as get_user
from ..core.session import get_first_day, get_last_day
from ..db.session import SessionLocal
from ..models.master import Account, AttendanceType, Employee
from ..models.voucher import Attendance, Journal, Voucher, VoucherType
from ..schemas.auth import UserToken


router = APIRouter()


# Dependency
def get_db() -> Session:
    try:
        db = SessionLocal()
        yield db
    finally:
        db.close()


@router.post("")
def credit_salary(
    month: str = Body(..., embed=True),
    db: Session = Depends(get_db),
    user: UserToken = Security(get_user, scopes=["attendance"]),
):
    month = datetime.strptime(month, "%d-%b-%Y").date()

    start_date = get_first_day(month)
    finish_date = get_last_day(month)
    voucher = Voucher(
        date=finish_date,
        narration="Auto Generated Salary Entry",
        user_id=user.id_,
        type_=VoucherType.by_name("Journal"),
        posted=True,
        poster_id=user.id_,
    )
    db.add(voucher)
    for item in salary_journals(start_date, finish_date, db):
        voucher.journals.append(item)
        db.add(item)
    db.commit()
    return {"message": "Salary Entry created"}


def salary_journals(start_date: date, finish_date: date, db: Session):
    days = monthrange(start_date.year, start_date.month)[1]
    amount = 0
    journals = []
    employees = (
        db.query(Employee)
        .filter(Employee.joining_date <= finish_date)
        .filter(or_(Employee.is_active, Employee.leaving_date >= start_date))
        .order_by(Employee.cost_centre_id)
        .order_by(Employee.designation)
        .order_by(Employee.name)
        .all()
    )
    for employee in employees:
        att = (
            db.query(Attendance)
            .filter(Attendance.employee_id == employee.id)
            .filter(Attendance.date >= start_date)
            .filter(Attendance.date <= finish_date)
            .filter(Attendance.is_valid == True)
            .all()
        )
        att = sum(map(lambda x: AttendanceType.by_id(x.attendance_type).value, att))
        att = round(att * employee.salary / days)
        if att != 0:
            amount += att
            journals.append(
                Journal(
                    amount=att,
                    debit=-1,
                    account_id=employee.id,
                    cost_centre_id=employee.cost_centre_id,
                )
            )
    salary = db.query(Account).filter(Account.id == Account.salary_id()).first()
    if amount == 0:
        raise HTTPException(
            status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
            detail="No salaries to credit",
        )
    journals.append(
        Journal(
            amount=amount,
            debit=1,
            account_id=salary.id,
            cost_centre_id=salary.cost_centre_id,
        )
    )
    return journals