"""funds.py - Funds report from Beancount

This tool produces a report of account balances for restricted funds,

including income, expenses, and realized gain/loss over a given time period.

Restricted funds are designated with the "project" metadata.

Specify the date range you want to report with the ``--begin`` and ``--end``

options.

Select the accounts you want to report with the ``--account`` option. You can

specify this option multiple times. The report will include at least one sheet

for each account you specify. Subaccounts will be reported on that sheet as

well.

Select the postings you want to report by passing metadata search terms in

``name=value`` format.

Run ``ledger-report --help`` for abbreviations and other options.

Examples

--------

Generate a report of all restricted funds in ODS format over the last year::

      fund-report

Query a specific restricted fund and get a quick balance on the terminal::

      fund-report <PROJECT>

"""

# Copyright © 2020  Brett Smith

#

# 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 argparse

import collections

import datetime

import enum

import locale

import logging

import sys

from typing import (

    Dict,

    Iterable,

    Iterator,

    Mapping,

    Optional,

    Sequence,

    TextIO,

    Tuple,

)

from ..beancount_types import (

    MetaValue,

)

from pathlib import Path

import odf.table  # type:ignore[import]

from beancount.parser import printer as bc_printer

from . import core

from .. import books

from .. import cliutil

from .. import config as configmod

from .. import data

AccountsMap = Mapping[data.Account, core.PeriodPostings]

FundPosts = Tuple[MetaValue, AccountsMap]

EQUITY_ACCOUNTS = ['Equity', 'Income', 'Expenses']

INFO_ACCOUNTS = [

    'Assets:Receivable',

    'Assets:Prepaid',

    'Liabilities:Payable',

    'Liabilities:UnearnedIncome',

]

PROGNAME = 'fund-report'

UNRESTRICTED_FUND = 'Conservancy'

logger = logging.getLogger('conservancy_beancount.reports.fund')

class ODSReport(core.BaseODS[FundPosts, None]):

    def __init__(self, start_date: datetime.date, stop_date: datetime.date) -> None:

        super().__init__()

        self.start_date = start_date

        self.stop_date = stop_date

        self.unrestricted: AccountsMap = {}

    def section_key(self, row: FundPosts) -> None:

        return None

    def start_spreadsheet(self) -> None:

        for width in [2.5, 1.5, 1.2, 1.2, 1.2, 1.5, 1.2, 1.3, 1.2, 1.3]:

            col_style = self.column_style(width)

            self.sheet.addElement(odf.table.TableColumn(stylename=col_style))

        center_bold = self.merge_styles(self.style_centertext, self.style_bold)

        self.add_row(

            self.string_cell(

                "Fund", stylename=self.merge_styles(self.style_endtext, self.style_bold),

            ),

            self.multiline_cell(["Balance as of", self.start_date.isoformat()],

                                stylename=center_bold),

            self.string_cell("Income", stylename=center_bold),

            self.string_cell("Expenses", stylename=center_bold),

            self.multiline_cell(["Realized", "Gain/Loss"], stylename=center_bold),

            self.multiline_cell(["Balance as of", self.stop_date.isoformat()],

                                stylename=center_bold),

            self.multiline_cell(["Of Which", "Receivable"], stylename=center_bold),

            self.multiline_cell(["Of Which", "Prepaid Expenses"], stylename=center_bold),

            self.multiline_cell(["Of Which", "Payable"], stylename=center_bold),

            self.multiline_cell(["Of Which", "Unearned Income"], stylename=center_bold),

        )

        self.lock_first_row()

        self.add_row()

        self.add_row(self.string_cell(

            f"Fund Report From {self.start_date.isoformat()} To {self.stop_date.isoformat()}",

            stylename=center_bold,

            numbercolumnsspanned=6,

        ))

        self.add_row()

    def _row_balances(self, accounts_map: AccountsMap) -> Iterable[core.Balance]:

        acct_order = ['Income', 'Expenses', 'Equity']

        key_order = [core.OPENING_BALANCE_NAME, *acct_order, core.ENDING_BALANCE_NAME]

        balances: Dict[str, core.Balance] = {key: core.MutableBalance() for key in key_order}

        for acct_s, balance in core.account_balances(accounts_map, acct_order):

            if acct_s in balances:

                balances[acct_s] = balance

            else:

                acct_root, _, _ = acct_s.partition(':')

                balances[acct_root] += balance

        for key in key_order:

            if key == 'Expenses':

                yield balances[key]

            else:

                yield -balances[key]

        for info_key in INFO_ACCOUNTS:

            for _, balance in core.account_balances(accounts_map, [info_key]):

                pass

            yield core.normalize_amount_func(info_key)(balance)

    def write_row(self, row: FundPosts) -> None:

        fund, accounts_map = row

        if fund == UNRESTRICTED_FUND:

            assert not self.unrestricted

            self.unrestricted = accounts_map

            return

        self.add_row(

            self.string_cell(fund, stylename=self.style_endtext),

            *(self.balance_cell(bal) for bal in self._row_balances(accounts_map)),

        )

    def write(self, rows: Iterable[FundPosts]) -> None:

        super().write(rows)

        if self.unrestricted:

            self.add_row()

            self.write_row(("Unrestricted", self.unrestricted))

class TextReport:

    def __init__(self,

                 start_date: datetime.date,

                 stop_date: datetime.date,

                 out_file: TextIO) -> None:

        self.start_date = start_date

        self.stop_date = stop_date

        self.out_file = out_file

    def _account_balances(self,

                          fund: str,

                          account_map: AccountsMap,

    ) -> Iterator[Tuple[str, Sequence[str]]]:

        total_fmt = f'{fund} balance as of {{}}'

        for acct_s, balance in core.account_balances(account_map, EQUITY_ACCOUNTS):

            if acct_s is core.OPENING_BALANCE_NAME:

                acct_s = total_fmt.format(self.start_date.isoformat())

            elif acct_s is core.ENDING_BALANCE_NAME:

                acct_s = total_fmt.format(self.stop_date.isoformat())

            yield acct_s, (-balance).format(None, sep='\0').split('\0')

        for _, account in core.sort_and_filter_accounts(account_map, INFO_ACCOUNTS):

            balance = account_map[account].stop_bal

            if not balance.is_zero():

                balance = core.normalize_amount_func(account)(balance)

                yield account, balance.format(None, sep='\0').split('\0')

    def write(self, rows: Iterable[FundPosts]) -> None:

        output = [

            line

            for fund, account_map in rows

            for line in self._account_balances(fund, account_map)

        ]

        acct_width = max(len(acct_s) for acct_s, _ in output) + 2

        bal_width = max(len(s) for _, bal_s in output for s in bal_s)

        bal_width = max(bal_width, 8)

        line_fmt = f'{{:>{acct_width}}}  {{:>{bal_width}}}'

        print(line_fmt.replace('{:>', '{:^').format("ACCOUNT", "BALANCE"),

              file=self.out_file)

        fund_start = f' balance as of {self.start_date.isoformat()}'

        for acct_s, bal_seq in output:

            if acct_s.endswith(fund_start):

                print(line_fmt.format('―' * acct_width, '―' * bal_width),

                      file=self.out_file)

            bal_iter = iter(bal_seq)

            print(line_fmt.format(acct_s, next(bal_iter)), file=self.out_file)

            for bal_s in bal_iter:

                print(line_fmt.format('', bal_s), file=self.out_file)

class ReportType(enum.Enum):

    TEXT = TextReport

    ODS = ODSReport

    TXT = TEXT

    SPREADSHEET = ODS

    @classmethod

    def from_arg(cls, s: str) -> 'ReportType':

        try:

            return cls[s.upper()]

        except KeyError:

            raise ValueError(f"no report type matches {s!r}") from None

class ReturnFlag(enum.IntFlag):

    LOAD_ERRORS = 1

    NOTHING_TO_REPORT = 8

def parse_arguments(arglist: Optional[Sequence[str]]=None) -> argparse.Namespace:

    parser = argparse.ArgumentParser(prog=PROGNAME)

    cliutil.add_version_argument(parser)

    parser.add_argument(

        '--begin', '--start', '-b',

        dest='start_date',

        metavar='DATE',

        type=cliutil.date_arg,

        help="""Date to start reporting entries, inclusive, in YYYY-MM-DD format.

The default is one year ago.

""")

    parser.add_argument(

        '--end', '--stop', '-e',

        dest='stop_date',

        metavar='DATE',

        type=cliutil.date_arg,

        help="""Date to stop reporting entries, exclusive, in YYYY-MM-DD format.

The default is a year after the start date.

""")

    parser.add_argument(

        '--report-type', '-t',

        metavar='TYPE',

from beancount import loader as bc_loader

from conservancy_beancount import data

from conservancy_beancount.reports import core

from conservancy_beancount.reports import fund

from decimal import Decimal

_ledger_load = bc_loader.load_file(testutil.test_path('books/fund.beancount'))

START_DATE = datetime.date(2018, 3, 1)

MID_DATE = datetime.date(2019, 3, 1)

STOP_DATE = datetime.date(2020, 3, 1)

EQUITY_ROOT_ACCOUNTS = ('Expenses:', 'Equity:', 'Income:')

OPENING_BALANCES = {

    'Alpha': 3000,

    'Bravo': 2000,

    'Charlie': 1000,

    'Conservancy': 4000,

}

BALANCES_BY_YEAR = {

    ('Conservancy', 2018): [

        ('Income:Other', 40),

        ('Expenses:Other', -4),

        ('Assets:Receivable:Accounts', 40),

        ('Liabilities:Payable:Accounts', 4),

    ],

    ('Conservancy', 2019): [

        ('Income:Other', 42),

        ('Expenses:Other', Decimal('-4.20')),

        ('Equity:Realized:CurrencyConversion', Decimal('6.20')),

        ('Assets:Receivable:Accounts', -40),

        ('Liabilities:Payable:Accounts', -4),

    ],

    ('Alpha', 2018): [

        ('Income:Other', 60),

        ('Liabilities:UnearnedIncome', 30),

        ('Assets:Prepaid:Expenses', 20),

    ],

    ('Alpha', 2019): [

        ('Income:Other', 30),

        ('Expenses:Other', -26),

        ('Assets:Prepaid:Expenses', -20),

        ('Liabilities:UnearnedIncome', -30),

    ],

    ('Bravo', 2018): [

        ('Expenses:Other', -20),

    ],

    ('Bravo', 2019): [

        ('Income:Other', 200),

    ],

}

@pytest.fixture

def fund_entries():

    return copy.deepcopy(_ledger_load[0])

def split_text_lines(output):

    for line in output:

        account, amount = line.rsplit(None, 1)

        yield account.strip(), amount

def format_amount(amount, currency='USD'):

    return babel.numbers.format_currency(

        amount, currency, format_type='accounting',

    )

def check_text_balances(actual, expected, *expect_accounts):

    balance = Decimal()

    for expect_account in expect_accounts:

        expect_amount = expected[expect_account]

        if expect_amount:

            actual_account, actual_amount = next(actual)

            assert actual_account == expect_account

            assert actual_amount == format_amount(expect_amount)

            balance += expect_amount

    return balance

def check_text_report(output, project, start_date, stop_date):

    _, _, project = project.rpartition('=')

    balance_amount = Decimal(OPENING_BALANCES[project])

    expected = collections.defaultdict(Decimal)

    for year in range(2018, stop_date.year):

        try:

            amounts = BALANCES_BY_YEAR[(project, year)]

        except KeyError:

            pass

        else:

            for account, amount in amounts:

                if year < start_date.year and account.startswith(EQUITY_ROOT_ACCOUNTS):

                    balance_amount += amount

                else:

                    expected[account] += amount

    actual = split_text_lines(output)

    next(actual); next(actual)  # Discard headers

    open_acct, open_amt = next(actual)

    assert open_acct == "{} balance as of {}".format(

        project, start_date.isoformat(),

    )

    assert open_amt == format_amount(balance_amount)

    balance_amount += check_text_balances(

        actual, expected,

        'Equity:Realized:CurrencyConversion',

        'Income:Other',

        'Expenses:Other',

    )

    end_acct, end_amt = next(actual)

    assert end_acct == "{} balance as of {}".format(

        project, stop_date.isoformat(),

    )

    assert end_amt == format_amount(balance_amount)

    balance_amount += check_text_balances(

        actual, expected,

        'Assets:Receivable:Accounts',

        'Assets:Prepaid:Expenses',

        'Liabilities:Payable:Accounts',

        'Liabilities:UnearnedIncome',

    )

    assert next(actual, None) is None

def check_cell_balance(cell, balance):

    if balance:

        assert cell.value == balance

    else:

        assert not cell.value

def check_ods_report(ods, start_date, stop_date):

    account_bals = collections.OrderedDict((key, {

        'opening': Decimal(amount),

        'Income': Decimal(0),

        'Expenses': Decimal(0),

        'Equity:Realized': Decimal(0),

        'Assets:Receivable': Decimal(0),

        'Assets:Prepaid': Decimal(0),

        'Liabilities:Payable': Decimal(0),

        'Liabilities': Decimal(0),  # UnearnedIncome

    }) for key, amount in sorted(OPENING_BALANCES.items()))

    for fund, year in itertools.product(account_bals, range(2018, stop_date.year)):

        try:

            amounts = BALANCES_BY_YEAR[(fund, year)]

        except KeyError:

            pass

        else:

            for account, amount in amounts:

                if year < start_date.year and account.startswith(EQUITY_ROOT_ACCOUNTS):

                    acct_key = 'opening'

                else:

                    acct_key, _, _ = account.rpartition(':')

                account_bals[fund][acct_key] += amount

def run_main(out_type, arglist, config=None):

    if config is None:

        config = testutil.TestConfig(

            books_path=testutil.test_path('books/fund.beancount'),

        )

    arglist.insert(0, '--output-file=-')

    output = out_type()

    errors = io.StringIO()

    retcode = fund.main(arglist, output, errors, config)

    output.seek(0)

    return retcode, output, errors

@pytest.mark.parametrize('project,start_date,stop_date', [

    ('Conservancy', START_DATE, STOP_DATE),

    ('project=Conservancy', MID_DATE, STOP_DATE),

    ('Conservancy', START_DATE, MID_DATE),

    ('Alpha', START_DATE, STOP_DATE),

    ('project=Alpha', MID_DATE, STOP_DATE),

    ('Alpha', START_DATE, MID_DATE),

    ('Bravo', START_DATE, STOP_DATE),

    ('project=Bravo', MID_DATE, STOP_DATE),

    ('Bravo', START_DATE, MID_DATE),

    ('project=Charlie', START_DATE, STOP_DATE),

])

def test_text_report(project, start_date, stop_date):

    retcode, output, errors = run_main(io.StringIO, [

        '-b', start_date.isoformat(), '-e', stop_date.isoformat(), project,

    ])

    assert not errors.getvalue()

    assert retcode == 0

    check_text_report(output, project, start_date, stop_date)

@pytest.mark.parametrize('start_date,stop_date', [

    (START_DATE, STOP_DATE),

    (MID_DATE, STOP_DATE),

    (START_DATE, MID_DATE),

])

def test_ods_report(start_date, stop_date):

    retcode, output, errors = run_main(io.BytesIO, [

        '--begin', start_date.isoformat(), '--end', stop_date.isoformat(),

    ])

    assert not errors.getvalue()

    assert retcode == 0

    ods = odf.opendocument.load(output)

    check_ods_report(ods, start_date, stop_date)

def test_main_no_postings(caplog):

    retcode, output, errors = run_main(io.StringIO, ['NonexistentProject'])

    assert retcode == 24

    assert any(log.levelname == 'WARNING' for log in caplog.records)