#!/usr/bin/env python3
# Copyright 2019 vgm+dev@devys.org
# SPDX-License-Identifier: MIT

progname = 'ofx2json'

# be explicit about __doc__ to allow progname to be defined first
__doc__ = f'''
Convert ofx from input file (or stdin if no FILENAME) to json on stdout.

Usage: {progname} [options] [--] [FILENAME...]
       {progname} -h|--help

Options:
  -h, --help  Display this help message
  -n          option doing n
  -N ARG      option doing N with ARG
'''


### standard modules
import collections
import datetime
import decimal
import io
import json
import os
import subprocess
import sys
### external modules
import docopt
import ofxparse

# This script is not compatible below python3.7.2, always abort (not in main
# since the syntax itself can cause the script to fail later inconveniently).
assert sys.hexversion >= 0x03070200


def map_ofx_transaction(transaction):
    return collections.OrderedDict(
            amount=transaction.amount,
            checknum=transaction.checknum,
            date=transaction.date,
            id=transaction.id,
            mcc=transaction.mcc,
            memo=transaction.memo,
            payee=transaction.payee,
            sic=transaction.sic,
            type=transaction.type,
    )


def map_ofx_statement(statement):
    return collections.OrderedDict(
            available_balance=statement.available_balance,
            available_balance_date=statement.available_balance_date,
            balance=statement.balance,
            balance_date=statement.balance_date,
            currency=statement.currency,
            discarded_entries=statement.discarded_entries,
            end_date=statement.end_date,
            start_date=statement.start_date,
            transactions=[map_ofx_transaction(i)
                          for i in statement.transactions],
            warnings=statement.warnings,
    )


def map_ofx_account(account):
    return collections.OrderedDict(
            account_id=account.account_id,
            account_type=account.account_type,
            branch_id=account.branch_id,
            curdef=account.curdef,
            institution=account.institution,
            number=account.number,
            rounting_number=account.routing_number,
            statement=map_ofx_statement(account.statement),
            type=account.type,
            warnings=account.warnings,
    )


def map_ofx(ofx):
    return collections.OrderedDict(
            headers=ofx.headers,
            accounts=[map_ofx_account(i) for i in ofx.accounts],
    )


def parse_ofx(filepaths):
    if not filepaths:
        yield ofxparse.OfxParser.parse(io.StringIO(sys.stdin.read()))
    else:
        for filepath in filepaths:
            with open(filepath) as fh:
                yield ofxparse.OfxParser.parse(fh)


def main():
    'function called only when script invoked directly on command line'
    args = docopt.docopt(__doc__)

    def json_default(obj):
        if isinstance(obj, decimal.Decimal):
            return str(obj) # no rounding by dumping a string, not float
        elif hasattr(obj, 'isoformat'):
            return obj.isoformat()
        print(f'error for {obj}')
        raise TypeError

    print(json.dumps(list(map(map_ofx, parse_ofx(args['FILENAME']))),
                     indent=2, default=json_default))

main()