Convert PDF to CSV for Rocketbank (Рокетбанк)

rocketpdftocsv.py

#!/bin/python3

"""
    Конвертирует транзакции Рокетбанка (https://rocketbank.ru) из PDF в CSV.
    Выводит в UTF8.
    Зависимости:
        - Poppler. В PATH: 'pdftotext'
          https://poppler.freedesktop.org/
          https://jlk.fjfi.cvut.cz/arch/manpages/man/pdftotext.1

    Автор: w1ld at inbox dot ru

    Releases:
    - Before 2019-09-16. Using SumatraPDf
    - 2019-09-16. Using Poppler. Adding checks for a day. Output to STDOUT.
"""

import sys
import re
import csv
from decimal import Decimal
from subprocess import getoutput

PDFTOTEXTCLI = 'pdftotext'

if len(sys.argv) == 0:
    print('Usage: import-rocket-pdftocsv.py [pdf]')
    exit()

def parse_amount(amount_raw):
    assert amount_raw
    amount = amount_raw.replace(' ', '')
    amount = amount.replace(',', '.')
    return Decimal(amount)

# Construct re patterns.
currency_p = '[A-Z]{1,4}'
amount_p = '-?\d[\d ]*(,\d+)? ' + currency_p
def parse_amount_currency(amount_currency):
    *amount_vals, currency = amount_currency.split(' ')
    amount = parse_amount(' '.join(amount_vals))
    return amount, currency

transaction_p_base = r'(?m)^$^\n( +)(?P<d1>\S[^\n]+\S) {{2,}}(?P<a>{})(?P<d2>(\n\1\S[^\n]*)*)\n^$'
transaction_re = re.compile(transaction_p_base.format(amount_p))

table_header_re = re.compile(r'\s*Дата\s+Описание\s+Расход\s+Приход\s+Входящий остаток\s*')
table_bottom_re = re.compile(r'^\s*Итог:\s+(?P<income>' + amount_p + ')\s+(?P<outcom>' + amount_p + ')\s*$')

date_re = re.compile('(?m)^(?P<date>\d{2}\.\d{2}\.\d{4})\s+(?P<d_amount>' + amount_p + ')$')

total_in_re = re.compile('Входящий остаток:\s+(' + amount_p + ')')
total_out_re = re.compile('Исходящий остаток:\s+(' + amount_p + ')')


def _transaction_iterator(pdftext):
    # Iterate from table header till table bottom by a date.
    th_match = table_header_re.search(pdftext)
    assert th_match
    from_ = th_match.end(0)
    date_m = date_re.search(pdftext, from_)

    total_in_m = total_in_re.search(pdftext)
    assert total_in_m
    balance_amount, balance_currency = parse_amount_currency(total_in_m.group(1))

    total_out_m = total_out_re.search(pdftext)
    assert total_out_m
    balance_out_amount, balance_out_currency = parse_amount_currency(total_out_m.group(1))

    while date_m:
        date_balance, date_currency = parse_amount_currency(date_m.groupdict()['d_amount'])
        if balance_amount != date_balance:
            raise Exception('Invalid balance: {} != {}.'.format(balance_amount, date_balance))

        from_ = date_m.start(0)
        next_date_m = date_re.search(pdftext, date_m.end(0))
        to_ = next_date_m.start(0) if next_date_m else len(pdftext)-1
        date_val = date_m.groupdict()['date']

        # Iterate over all transactions in this day.
        for transaction_m in transaction_re.finditer(pdftext, pos=from_, endpos=to_):
            mdict = transaction_m.groupdict()
            description = mdict['d1']
            amount, currency = parse_amount_currency(mdict['a'])
            assert currency == balance_currency
            balance_amount += amount   # For checks. Expense comes with '-'. Income is positive.
            d_remain = mdict['d2']
            if d_remain:
                d_remain = d_remain.strip()
                # Concat:
                d_remain = re.sub(r' {2,}', r' ', d_remain)
                description += ' ' + d_remain
            description = description.replace('\n', '')
            yield [date_val, description, amount, currency, balance_amount]
        date_m = next_date_m

    # Check balance for last day.
    if balance_amount != balance_out_amount:
        raise Exception('Invalid balance: {} != {}'.format(balance_amount, balance_out_amount))


pdffilename = sys.argv[1]
pdftext = getoutput(PDFTOTEXTCLI + ' -layout "' + pdffilename + '" -')
assert pdftext

with sys.stdout as f:
    w = csv.writer(f)
    w.writerow(['date','description','amount', 'currency', 'balance'])
    for trn in _transaction_iterator(pdftext):
        w.writerow(trn)