import datetime
import uuid

import brewman.schemas.reports as schemas

from fastapi import APIRouter, Depends, Request, Security
from sqlalchemy.orm import Session, joinedload_all
from sqlalchemy.sql.expression import func

from ...core.security import get_current_active_user as get_user
from ...core.session import get_finish_date, get_start_date, set_period
from ...db.session import SessionLocal
from ...models.master import AccountBase
from ...models.voucher import Journal, Voucher, VoucherType
from ...schemas.auth import UserToken


router = APIRouter()


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


@router.get("", response_model=schemas.Ledger)
def show_blank(
    request: Request,
    user: UserToken = Security(get_user, scopes=["ledger"]),
):
    return {
        "startDate": get_start_date(request.session),
        "finishDate": get_finish_date(request.session),
        "account": None,
        "body": [],
    }


@router.get("/{id_}", response_model=schemas.Ledger)
def show_data(
    id_: uuid.UUID,
    request: Request,
    s: str = None,
    f: str = None,
    db: Session = Depends(get_db),
    user: UserToken = Security(get_user, scopes=["ledger"]),
):
    account = db.query(AccountBase).filter(AccountBase.id == id_).first()
    start_date = s if s is not None else get_start_date(request.session)
    finish_date = f if f is not None else get_finish_date(request.session)
    body = build_report(account.id, start_date, finish_date, db)
    set_period(start_date, finish_date, request.session)
    return {
        "startDate": start_date,
        "finishDate": finish_date,
        "account": {"id": account.id, "name": account.name},
        "body": body,
    }


def build_report(account_id, start_date, finish_date, db):
    body = []
    opening = opening_balance(account_id, start_date, db)
    body.append(opening)

    query = (
        db.query(Voucher)
        .options(joinedload_all(Voucher.journals, Journal.account, innerjoin=True))
        .filter(Voucher.journals.any(Journal.account_id == account_id))
        .filter(Voucher.date >= datetime.datetime.strptime(start_date, "%d-%b-%Y"))
        .filter(Voucher.date <= datetime.datetime.strptime(finish_date, "%d-%b-%Y"))
        .filter(Voucher.type != VoucherType.by_name("Issue").id)
        .order_by(Voucher.date)
        .order_by(Voucher.last_edit_date)
        .all()
    )

    for voucher in query:
        debit = 0
        credit = 0
        journal_debit = 0
        name = ""
        for journal in voucher.journals:
            if journal.account_id == account_id:
                journal_debit = journal.debit
                if journal.debit == 1:
                    debit = journal.amount
                    credit = 0
                else:
                    credit = journal.amount
                    debit = 0
        for journal in voucher.journals:
            if journal.debit != journal_debit:
                name += "{0} / ".format(journal.account.name)
        name = name[:-3]
        body.append(
            {
                "id": voucher.id,
                "date": voucher.date.strftime("%d-%b-%Y"),
                "name": name,
                "url": [
                    "/",
                    VoucherType.by_id(voucher.type).name.replace(" ", "-").lower(),
                    str(voucher.id),
                ],
                "type": VoucherType.by_id(voucher.type).name,
                "narration": voucher.narration,
                "debit": debit,
                "credit": credit,
                "posted": voucher.posted,
            }
        )
    return body


def opening_balance(account_id, start_date, db):
    opening = (
        db.query(func.sum(Journal.amount * Journal.debit))
        .join(Journal.voucher)
        .filter(Voucher.date < datetime.datetime.strptime(start_date, "%d-%b-%Y"))
        .filter(Voucher.type != VoucherType.by_name("Issue").id)
        .filter(Journal.account_id == account_id)
        .scalar()
    )
    opening = 0 if opening is None else opening
    if opening < 0:
        credit = opening * -1
        debit = 0
    else:
        debit = opening
        credit = 0
    return {
        "date": start_date,
        "id": None,
        "name": "Opening Balance",
        "type": "Opening Balance",
        "url": [],
        "narration": "",
        "debit": debit,
        "credit": credit,
        "posted": True,
    }