Kata

In this kata, you're going to do the bookkeeping for a newly started business, doing some debit, some credit, and putting together the fiscal reports at the end of the year. Since the business just started out and you live in a free society, the fiscal reports will be very simple and no tax is beeing payed. All payments are cash payments.

BALANCE SHEET:

ASSETS:
Materials: value
Property: value
Cash: value
TOTAL: value

LIABILITIES:
Equity: value
Loans: value
TOTAL: value

RESULT REPORT:

RESULT:
Revenue: $
Costs: $
Profit: $

INPUT:

cash: an integer representing the amount of cash on the balance sheet at the beginning of the year
materials_left: an integer representing the worth of the raw materials left at the end of the year
loans: a list of objects of Loan-type (see below for info)
property: a list of objects of Property-type (see below for info)
transactions: a list of objects of Transaction-type (see below for info)

class Loan:
    def __init__(self, worth, mortgage, interest):
        self.worth = worth # (int) the amount of money borrowed
        self.mortgage = mortgage # (int) the amount of money payed in mortgage at the end of the year
        self.interest = interest # (float 0 < x < 1) interest payed at the end of the year

class Property:
    def __init__(self, worth, depreciation):
        self.worth = worth # (int) value of property
        self.depreciation = depreciation # (int) the amount the property decreases in value at the end of the year
        
class Transaction:
    def __init__(self, type, worth):
        self.type = type # (str) 'BUY' or 'SELL'. 'BUY' = more raw materials are purchased, 'SELL' = products are sold
        self.worth = worth # value of transaction

OUTPUT:

Given the input, your task is to make all the transactions and return a single string containing the balance sheet and result report at the end of the year. String format:

ASSETS:
Materials: $
Property: $
Cash: $
TOTAL: $

LIABILITIES:
Equity: $
Loans: $
TOTAL: $

RESULT:
Revenue: $
Costs: $
Profit: $

NOTES:

What are costs? Costs = Value of materials in goods sold + depreciation + interest. There are no materials in storage at the beginning of the year.

What is depreciation? Depreciation is the annual decrease in value of property or other non-current assets. Depreciation doesn't affect the cashflow.

Mortgage and interest: Mortgage and interest will be payed in cash at the end of the year. When paying interest, round each amount to nearest integer. So if you have a loan for 101 and the interest is 0.1, you should pay 10 in interest for that loan. Only mortgage will affect the loan balance.

Profit/loss: Revenue - Costs = Profit/Loss. The profit/loss is added to Equity.

Balance sheet: First rule in accounting: Assets = Liabilites. If this isn't true at the end of the year, you've made a mistake. The worth of Equity at the beginning of the year isn't given as input, but is easily derived from the input given.

Transactions: Other than the objects of Transaction-type, mortgage and interest payments are also transactions. In all transactions, cash is either flowing in or out, depending on the nature of the transaction.

Revenue: Goods are delivered instantaneously, meaning sold goods are revenue.

Useful information: https://en.wikipedia.org/wiki/Double-entry_bookkeeping

FEEDBACK:

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