ledger-pyreport/ledger_pyreport/accounting.py

169 lines
7.1 KiB
Python

# ledger-pyreport
# Copyright © 2020 Lee Yingtong Li (RunasSudo)
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program. If not, see <https://www.gnu.org/licenses/>.
import csv
from datetime import timedelta
from decimal import Decimal
import math
from .model import *
# Generate a trial balance
# Perform closing of books based on specified dates
def trial_balance_raw(ledger, date, pstart):
tb = TrialBalance(ledger, date, pstart)
for transaction in ledger.transactions:
if transaction.date > date:
continue
for posting in transaction.postings:
if (posting.account.is_income or posting.account.is_expense) and transaction.date < pstart:
tb.balances[config['retained_earnings']] = tb.get_balance(ledger.get_account(config['retained_earnings'])) + posting.amount
elif posting.account.is_oci and transaction.date < pstart:
tb.balances[config['accumulated_oci']] = tb.get_balance(ledger.get_account(config['retained_earnings'])) + posting.amount
else:
tb.balances[posting.account.name] = tb.get_balance(posting.account) + posting.amount
return tb
# Trial balance with unrealized gains and OCI
def trial_balance(ledger, date, pstart, currency):
tb_date, r_date = _add_unrealized_gains(trial_balance_raw(ledger, date, pstart), currency)
tb_pstart, r_pstart = _add_unrealized_gains(trial_balance_raw(ledger, pstart - timedelta(days=1), pstart), currency)
for account in set(list(r_date.keys()) + list(r_pstart.keys())):
if account in r_pstart:
# Charge previous unrealized gains to Accumulated OCI
#r_pstart[account].postings[1].account = ledger.get_account(config['accumulated_oci'])
accumulated = r_pstart[account].postings[0].amount
tb_date.balances[account.name] = tb_date.get_balance(account) + accumulated
tb_date.balances[config['accumulated_oci']] = tb_date.get_balance(ledger.get_account(config['accumulated_oci'])) - accumulated
if account in r_date:
if account in r_pstart:
# Adjust for this year's unrealized gains only
r_date[account].postings[0].amount -= accumulated
r_date[account].postings[1].amount += accumulated
tb_date.balances[account.name] = tb_date.get_balance(account) + r_date[account].postings[0].amount
tb_date.balances[config['unrealized_gains']] = tb_date.get_balance(ledger.get_account(config['unrealized_gains'])) - r_date[account].postings[0].amount
return tb_date
# Adjust (in place) a trial balance for unrealized gains without accumulating OCI
def _add_unrealized_gains(tb, currency):
results = {}
unrealized_gain_account = tb.ledger.get_account(config['unrealized_gains'])
for account in list(tb.ledger.accounts.values()):
if not account.is_market:
continue
total_cost = tb.get_balance(account).exchange(currency, True)
total_market = tb.get_balance(account).exchange(currency, False, tb.date, tb.ledger)
unrealized_gain = total_market - total_cost
if unrealized_gain != 0:
transaction = Transaction(tb.ledger, None, tb.date, '<Unrealized Gains>')
transaction.postings.append(Posting(transaction, account, unrealized_gain))
transaction.postings.append(Posting(transaction, unrealized_gain_account, -unrealized_gain))
tb.ledger.transactions.append(transaction)
results[account] = transaction
return tb, results
# Adjust (in place) a trial balance to include a Current Year Earnings account
# Suitable for display on a balance sheet
def balance_sheet(tb):
# Calculate Profit/Loss
total_pandl = tb.get_total(tb.ledger.get_account(config['income_account'])) + tb.get_total(tb.ledger.get_account(config['expenses_account']))
# Add Current Year Earnings account
tb.balances[config['current_year_earnings']] = tb.get_balance(tb.ledger.get_account(config['current_year_earnings'])) + total_pandl
# Calculate OCI
total_oci = tb.get_total(tb.ledger.get_account(config['oci_account']))
# Add Current Year OCI account
tb.balances[config['current_year_oci']] = tb.get_balance(tb.ledger.get_account(config['current_year_oci'])) + total_oci
return tb
def account_to_cash(account, currency):
# Apply FIFO methodology to match postings
balance = [] # list of [posting, amount to balance, amount remaining, balancing list of [posting, amount balanced]]
for transaction in account.ledger.transactions[:]:
if any(p.account == account for p in transaction.postings):
for posting in transaction.postings[:]:
if posting.account == account:
#transaction.postings.remove(posting)
pass
else:
# Try to balance postings
amount_to_balance = posting.amount.exchange(currency, True).amount
while amount_to_balance != 0:
balancing_posting = next((b for b in balance if b[2] != 0 and math.copysign(1, b[2]) != math.copysign(1, amount_to_balance)), None)
if balancing_posting is None:
break
if abs(balancing_posting[2]) >= abs(amount_to_balance):
balancing_posting[3].append([posting, amount_to_balance])
balancing_posting[2] += amount_to_balance
amount_to_balance = Decimal(0)
break
else:
balancing_posting[3].append([posting, -balancing_posting[2]])
amount_to_balance += balancing_posting[2]
balancing_posting[2] = Decimal(0)
if amount_to_balance != 0:
# New unbalanced remainder
balance.append([posting, amount_to_balance, amount_to_balance, []])
transaction.postings = []
# Finalise balanced postings
for orig_posting, amount_to_balance, amount_remaining, balancing_postings in balance:
posting = Posting(orig_posting.transaction, orig_posting.account, Amount(amount_to_balance, currency))
posting.transaction.postings.append(posting)
for balancing_posting, amount_balanced in balancing_postings:
posting.transaction.postings.append(Posting(posting.transaction, balancing_posting.account, Amount(amount_balanced, currency)))
if balancing_posting in balancing_posting.transaction.postings:
balancing_posting.transaction.postings.remove(balancing_posting)
if amount_remaining != 0:
if posting.account.is_asset:
# Cash - charge any unbalanced remainder to Other Income
posting.transaction.postings.append(Posting(posting.transaction, account.ledger.get_account(config['cash_other_income']), Amount(-amount_remaining, currency)))
else:
# Liabilities, etc. - discard any unbalanced remainder
posting.amount.amount -= amount_remaining
# Adjust (in place) a ledger to convert accounting to a cash basis
def ledger_to_cash(ledger, currency):
for account in list(ledger.accounts.values()):
if not (account.is_cash or account.is_income or account.is_expense or account.is_equity):
account_to_cash(account, currency)
return ledger