@overload

    def slice_parts(self, start: int, stop: None=None) -> str: ...

    def slice_parts(self,

                    start: Optional[Union[int, slice]]=None,

                    stop: Optional[int]=None,

    ) -> Sequence[str]:

        """Slice the account parts like they were a list

        Given a single index, return that part of the account name as a string.

        Otherwise, return a list of part names sliced according to the arguments.

        """

        if start is None:

            part_slice = slice(None)

        elif isinstance(start, slice):

            part_slice = start

        elif stop is None:

            return self[self._find_part_slice(start)]

        else:

            part_slice = slice(start, stop)

        return self.split(self.SEP)[part_slice]

    def root_part(self, count: int=1) -> str:

        """Return the first part(s) of the account name as a string"""

        try:

            stop = self._find_part_slice(count - 1).stop

        except IndexError:

            return self

        else:

            return self[:stop]

class Amount(bc_amount.Amount):

    """Beancount amount after processing

    Beancount's native Amount class declares number to be Optional[Decimal],

    because the number is None when Beancount first parses a posting that does

    not have an amount, because the user wants it to be automatically balanced.

    As part of the loading process, Beancount replaces those None numbers

    with the calculated amount, so it will always be a Decimal. This class

    overrides the type declaration accordingly, so the type checker knows

    that our code doesn't have to consider the possibility that number is

    None.

    """

    number: decimal.Decimal

    # beancount.core._Amount is the plain namedtuple.

    # beancore.core.Amount adds instance methods to it.

    # b.c.Amount.__New__ calls `b.c._Amount.__new__`, which confuses type

    # checking. See <https://github.com/python/mypy/issues/1279>.

    # It works fine if you use super(), which is better practice anyway.

    # So we override __new__ just to call _Amount.__new__ this way.

    def __new__(cls, number: decimal.Decimal, currency: str) -> 'Amount':

        return super(bc_amount.Amount, Amount).__new__(cls, number, currency)

class Metadata(MutableMapping[MetaKey, MetaValue]):

    """Transaction or posting metadata

    This class wraps a Beancount metadata dictionary with additional methods

    for common parsing and query tasks.

    """

    __slots__ = ('meta',)

    def __init__(self, source: MutableMapping[MetaKey, MetaValue]) -> None:

        self.meta = source

    def __iter__(self) -> Iterator[MetaKey]:

        return iter(self.meta)

    def __len__(self) -> int:

        return len(self.meta)

    def __getitem__(self, key: MetaKey) -> MetaValue:

        return self.meta[key]

    def __setitem__(self, key: MetaKey, value: MetaValue) -> None:

        self.meta[key] = value

    def __delitem__(self, key: MetaKey) -> None:

        del self.meta[key]

    def get_links(self, key: MetaKey) -> Sequence[str]:

        try:

            value = self.meta[key]

        except KeyError:

            return ()

        if isinstance(value, str):

            return value.split()

        else:

            raise TypeError("{} metadata is a {}, not str".format(

                key, type(value).__name__,

            ))

class PostingMeta(Metadata):

    """Combined access to posting metadata with its parent transaction metadata

    This lets you access posting metadata through a single dict-like object.

    If you try to look up metadata that doesn't exist on the posting, it will

    look for the value in the parent transaction metadata instead.

    You can set and delete metadata as well. Changes only affect the metadata

    of the posting, never the transaction. Changes are propagated to the

    underlying Beancount data structures.

    Functionally, you can think of this as identical to:

      collections.ChainMap(post.meta, txn.meta)

    Under the hood, this class does a little extra work to avoid creating

    posting metadata if it doesn't have to.

    """

    __slots__ = ('txn', 'index', 'post')

    def __init__(self,

                 txn: Transaction,

                 index: int,

                 post: Optional[BasePosting]=None,

    ) -> None:

        if post is None:

            post = txn.postings[index]

        self.txn = txn

        self.index = index

        self.post = post

        if post.meta is None:

            self.meta = self.txn.meta

        else:

            self.meta = collections.ChainMap(post.meta, txn.meta)

    def __getitem__(self, key: MetaKey) -> MetaValue:

        try:

            return super().__getitem__(key)

        except KeyError:

            if key == 'entity' and self.txn.payee is not None:

                return self.txn.payee

            else:

                raise

    def __setitem__(self, key: MetaKey, value: MetaValue) -> None:

        if self.post.meta is None:

            self.post = self.post._replace(meta={key: value})

            self.txn.postings[self.index] = self.post

            # mypy complains that self.post.meta could be None, but we know

            # from two lines up that it's not.

            self.meta = collections.ChainMap(self.post.meta, self.txn.meta)  # type:ignore[arg-type]

        else:

            super().__setitem__(key, value)

    def __delitem__(self, key: MetaKey) -> None:

        if self.post.meta is None:

            raise KeyError(key)

        else:

            super().__delitem__(key)

    # This is arguably cheating a litttle bit, but I'd argue the date of

    # the parent transaction still qualifies as posting metadata, and

    # it's something we want to access so often it's good to have it

    # within easy reach.

    @property

    def date(self) -> datetime.date:

        return self.txn.date

class Posting(BasePosting):

    """Enhanced Posting objects

    This class is a subclass of Beancount's native Posting class where

    specific fields are replaced with enhanced versions:

    * The `account` field is an Account object

    * The `units` field is our Amount object (which simply declares that the

      number is always a Decimal—see that docstring for details)

    * The `meta` field is a PostingMeta object

    """

    __slots__ = ()

    account: Account

    units: Amount

    cost: Optional[bc_position.Cost]

    # mypy correctly complains that our MutableMapping is not compatible

    # with Beancount's meta type declaration of Optional[Dict]. IMO

    # Beancount's type declaration is a smidge too specific: I think its type

    # declaration should also use MutableMapping, because it would be very

    # unusual for code to specifically require a Dict over that.

    # If it did, this declaration would pass without issue.

    meta: PostingMeta  # type:ignore[assignment]

    @classmethod

    def from_beancount(cls,

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

class Sentinel:

    pass

class Account(NamedTuple):

    name: str

    aging_thresholds: Sequence[int]

class AccrualAccount(enum.Enum):

    # Note the aging report uses the same order accounts are defined here.

    # See AgingODS.start_spreadsheet().

    RECEIVABLE = Account('Assets:Receivable', [365, 120, 90, 60])

    PAYABLE = Account('Liabilities:Payable', [365, 90, 60, 30])

    @classmethod

    def account_names(cls) -> Iterator[str]:

        return (acct.value.name for acct in cls)

    @classmethod

    def by_account(cls, name: data.Account) -> 'AccrualAccount':

        for account in cls:

            if name.is_under(account.value.name):

                return account

        raise ValueError(f"unrecognized account {name!r}")

    @classmethod

    def classify(cls, related: core.RelatedPostings) -> 'AccrualAccount':

        for account in cls:

            account_name = account.value.name

            if all(post.account.is_under(account_name) for post in related):

                return account

        raise ValueError("unrecognized account set in related postings")

    @property

    def normalize_amount(self) -> Callable[[T], T]:

        return core.normalize_amount_func(self.value.name)

class AccrualPostings(core.RelatedPostings):

    __slots__ = (

        'accrual_type',

        'end_balance',

        'account',

        'entity',

        'invoice',

    )

    INCONSISTENT = Sentinel()

    def __init__(self,

                 source: Iterable[data.Posting]=(),

                 *,

                 _can_own: bool=False,

    ) -> None:

        super().__init__(source, _can_own=_can_own)

        # The following type declarations tell mypy about values set in the for

        # loop that are important enough to be referenced directly elsewhere.

        self.account = self._single_item(post.account for post in self)

        if isinstance(self.account, Sentinel):

            self.accrual_type: Optional[AccrualAccount] = None

            norm_func: Callable[[T], T] = lambda x: x

            entity_pred: Callable[[data.Posting], bool] = bool

        else:

            self.accrual_type = AccrualAccount.by_account(self.account)

            norm_func = self.accrual_type.normalize_amount

            entity_pred = lambda post: norm_func(post.units).number > 0

        self.entity = self._single_item(self.entities(entity_pred))

        self.invoice = self._single_item(self.first_links('invoice'))

        self.end_balance = norm_func(self.balance_at_cost())

    def _single_item(self, seq: Iterable[T]) -> Union[T, Sentinel]:

        items = iter(seq)

        try:

            item1 = next(items)

        except StopIteration:

            all_same = False

        else:

            all_same = all(item == item1 for item in items)

        return item1 if all_same else self.INCONSISTENT

    def entities(self, pred: Callable[[data.Posting], bool]=bool) -> Iterator[MetaValue]:

        seen: Set[MetaValue] = set()

        for post in self:

            if pred(post):

                try:

                    entity = post.meta['entity']

                except KeyError:

                    pass

                else:

                    if entity not in seen:

                        yield entity

                        seen.add(entity)

    def first_links(self, key: MetaKey, default: Optional[str]=None) -> Iterator[Optional[str]]:

    def make_consistent(self) -> Iterator[Tuple[MetaValue, 'AccrualPostings']]:

        account_ok = isinstance(self.account, str)

        entity_ok = isinstance(self.entity, str)

        # `'/' in self.invoice` is just our heuristic to ensure that the

        # invoice metadata is "unique enough," and not just a placeholder

        # value like "FIXME". It can be refined if needed.

        invoice_ok = isinstance(self.invoice, str) and '/' in self.invoice

        if account_ok and entity_ok and invoice_ok:

            yield (self.invoice, self)

            return

        groups = collections.defaultdict(list)

        for post in self:

            post_invoice = self.invoice if invoice_ok else (

                post.meta.get('invoice') or 'BlankInvoice'

            )

            post_entity = self.entity if entity_ok else (

                post.meta.get('entity') or 'BlankEntity'

            )

            groups[f'{post.account} {post_invoice} {post_entity}'].append(post)

        type_self = type(self)

        for group_key, posts in groups.items():

            yield group_key, type_self(posts, _can_own=True)

    def is_paid(self, default: Optional[bool]=None) -> Optional[bool]:

        if self.accrual_type is None:

            return default

        else:

            return self.end_balance.le_zero()

    def is_zero(self, default: Optional[bool]=None) -> Optional[bool]:

        if self.accrual_type is None:

            return default

        else:

            return self.end_balance.is_zero()

    def since_last_nonzero(self) -> 'AccrualPostings':

        for index, (post, balance) in enumerate(self.iter_with_balance()):

            if balance.is_zero():

                start_index = index

        try:

            empty = start_index == index

        except NameError:

            empty = True

        return self if empty else self[start_index + 1:]

class BaseReport:

    def __init__(self, out_file: TextIO) -> None:

        self.out_file = out_file

        self.logger = logger.getChild(type(self).__name__)

    def _report(self, posts: AccrualPostings, index: int) -> Iterable[str]:

        raise NotImplementedError("BaseReport._report")

    def run(self, groups: PostGroups) -> None:

        for index, invoice in enumerate(groups):

            for line in self._report(groups[invoice], index):

                print(line, file=self.out_file)

class AgingODS(core.BaseODS[AccrualPostings, Optional[data.Account]]):

    COLUMNS = [

        'Date',

        'Entity',

        'Invoice Amount',

        'Booked Amount',

        'Project',

        'Ticket',

        'Invoice',

        'Approval',

        'Contract',

        'Purchase Order',

    ]

    COL_COUNT = len(COLUMNS)

    def __init__(self,

                 rt_client: rt.Rt,

                 date: datetime.date,

                 logger: logging.Logger,

    ) -> None:

        super().__init__()

        self.rt_client = rt_client

        self.rt_wrapper = rtutil.RT(self.rt_client)

        self.date = date

        self.logger = logger

    def init_styles(self) -> None:

        super().init_styles()

        self.style_widecol = self.replace_child(

            self.document.automaticstyles,

            odf.style.Style,

            name='WideCol',

        )

        self.style_widecol.setAttribute('family', 'table-column')

        self.style_widecol.addElement(odf.style.TableColumnProperties(

"""Test Metadata class"""

# 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 pytest

from . import testutil

from conservancy_beancount import data

@pytest.fixture

def simple_txn(index=None, key=None):

    return testutil.Transaction(note='txn note', postings=[

        ('Assets:Cash', 5),

        ('Income:Donations', -5, {'note': 'donation love', 'extra': 'Extra'}),

    ])

SIMPLE_TXN_METAKEYS = frozenset(['filename', 'lineno', 'note'])

def test_metadata_transforms_source():

    source = {'1': 'one'}

    meta = data.Metadata(source)

    meta['2'] = 'two'

    assert source['2'] == 'two'

    del meta['1']

    assert set(source) == {'2'}

@pytest.mark.parametrize('value', [

    '',

    'link',

    '  link',

    'link  ',

    'link1  link2',

    ' link1  link2   link3    ',

])

def test_get_links(value):

    meta = data.Metadata({'key': value})

    assert list(meta.get_links('key')) == value.split()

def test_get_links_missing():

    meta = data.Metadata({})

    assert not meta.get_links('key')

@pytest.mark.parametrize('value', testutil.NON_STRING_METADATA_VALUES)

def test_get_links_bad_type(value):

    meta = data.Metadata({'key': value})

    with pytest.raises(TypeError):

        meta.get_links('key')