# -*- encoding: utf-8 -*-
##############################################################################
#
#    Copyright (C) 2011 credativ Ltd (<http://www.credativ.co.uk>).
#    All Rights Reserved
#
#    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 <http://www.gnu.org/licenses/>.
#
##############################################################################

from account_banking import sepa
from decimal import Decimal
import datetime
import re
import unicodedata

from openerp.tools import ustr


def strip_accents(string):
    res = unicodedata.normalize('NFKD', ustr(string))
    res = res.encode('ASCII', 'ignore')
    return res


def split_account_holder(holder):
    holder_parts = holder.split("\n")

    try:
        line2 = holder_parts[1]
    except IndexError:
        line2 = ''

    return holder_parts[0], line2


def address_truncate(name_address):
    addr_line = name_address.upper().split("\n")[0:5]
    addr_line = [s[:35] for s in addr_line]
    return addr_line


def edifact_isalnum(s):
    """The standard says alphanumeric characters, but spaces are also
    allowed
    """
    return bool(re.match(r'^[A-Za-z0-9 ]*$', s))


def edifact_digits(val, digits=None, mindigits=None):
    if digits is None:
        digits = ''
    if mindigits is None:
        mindigits = digits

    pattern = r'^[0-9]{' + str(mindigits) + ',' + str(digits) + r'}$'
    return bool(re.match(pattern, str(val)))


def edifact_isalnum_size(val, digits):
    pattern = r'^[A-Za-z0-9 ]{' + str(digits) + ',' + str(digits) + r'}$'
    return bool(re.match(pattern, str(val)))


class HasCurrency(object):
    def _get_currency(self):
        return self._currency

    def _set_currency(self, currency):
        if currency is None:
            self._currency = None
        else:
            if not len(currency) <= 3:
                raise ValueError("Currency must be <= 3 characters long: %s" %
                                 ustr(currency))

            if not edifact_isalnum(currency):
                raise ValueError("Currency must be alphanumeric: %s" %
                                 ustr(currency))

            self._currency = currency.upper()

    currency = property(_get_currency, _set_currency)


class LogicalSection(object):

    def __str__(self):
        segments = self.segments()

        def format_segment(segment):
            return '+'.join(
                [':'.join([str(strip_accents(y)) for y in x]) for x in segment]
            ) + "'"

        return "\n".join([format_segment(s) for s in segments])


def _fii_segment(self, party_qualifier):
    holder = split_account_holder(self.holder)
    account_identification = [self.number.replace(' ', ''), holder[0]]
    if holder[1] or self.currency:
        account_identification.append(holder[1])
    if self.currency:
        account_identification.append(self.currency)
    return [
        ['FII'],
        [party_qualifier],
        account_identification,
        self.institution_identification,
        [self.country],
    ]


class UKAccount(HasCurrency):
    def _get_number(self):
        return self._number

    def _set_number(self, number):
        if not edifact_digits(number, 8):
            raise ValueError("Account number must be 8 digits long: " +
                             str(number))

        self._number = number

    number = property(_get_number, _set_number)

    def _get_sortcode(self):
        return self._sortcode

    def _set_sortcode(self, sortcode):
        if not edifact_digits(sortcode, 6):
            raise ValueError("Account sort code must be 6 digits long: %s" %
                             ustr(sortcode))

        self._sortcode = sortcode

    sortcode = property(_get_sortcode, _set_sortcode)

    def _get_holder(self):
        return self._holder

    def _set_holder(self, holder):
        holder_parts = split_account_holder(holder)

        if not len(holder_parts[0]) <= 35:
            raise ValueError("Account holder must be <= 35 characters long: %s"
                             % ustr(holder_parts[0]))

        if not len(holder_parts[1]) <= 35:
            raise ValueError("Second line of account holder must be <= 35 "
                             "characters long: %s" % ustr(holder_parts[1]))

        if not edifact_isalnum(holder_parts[0]):
            raise ValueError("Account holder must be alphanumeric: %s" %
                             ustr(holder_parts[0]))

        if not edifact_isalnum(holder_parts[1]):
            raise ValueError("Second line of account holder must be "
                             "alphanumeric: %s" % ustr(holder_parts[1]))

        self._holder = holder.upper()

    holder = property(_get_holder, _set_holder)

    def __init__(self, number, holder, currency, sortcode):
        self.number = number
        self.holder = holder
        self.currency = currency
        self.sortcode = sortcode
        self.country = 'GB'
        self.institution_identification = ['', '', '', self.sortcode, 154, 133]

    def fii_bf_segment(self):
        return _fii_segment(self, 'BF')

    def fii_or_segment(self):
        return _fii_segment(self, 'OR')


class NorthAmericanAccount(UKAccount):

    def _set_account_ident(self):
        if self.origin_country in ('US', 'CA'):
            # Use the routing number
            account_ident = ['', '', '', self.sortcode, 155, 114]
        else:
            # Using the BIC/Swift Code
            account_ident = [self.bic, 25, 5, '', '', '']
        return account_ident

    def _set_sortcode(self, sortcode):
        if self.origin_country == 'CA' and self.is_origin_account:
            expected_digits = 6
        else:
            expected_digits = 9
        if not edifact_digits(sortcode, expected_digits):
            raise ValueError("Account routing number must be %d digits long: "
                             "%s" % (expected_digits, ustr(sortcode)))

        self._sortcode = sortcode

    def _get_sortcode(self):
        return self._sortcode

    sortcode = property(_get_sortcode, _set_sortcode)

    def _set_bic(self, bic):
        if (not edifact_isalnum_size(bic, 8) and
                not edifact_isalnum_size(bic, 11)):
            raise ValueError("Account BIC/Swift code must be 8 or 11 "
                             "characters long: %s" % ustr(bic))
        self._bic = bic

    def _get_bic(self):
        return self._bic

    bic = property(_get_bic, _set_bic)

    def _set_number(self, number):
        if not edifact_digits(number, mindigits=1):
            raise ValueError("Account number is invalid: %s" % ustr(number))

        self._number = number

    def _get_number(self):
        return self._number

    number = property(_get_number, _set_number)

    def __init__(self, number, holder, currency, sortcode, swiftcode, country,
                 origin_country=None, is_origin_account=False):
        self.origin_country = origin_country
        self.is_origin_account = is_origin_account
        self.number = number
        self.holder = holder
        self.currency = currency
        self.sortcode = sortcode
        self.country = country
        self.bic = swiftcode
        self.institution_identification = self._set_account_ident()


class SWIFTAccount(UKAccount):

    def _set_account_ident(self):
        # Using the BIC/Swift Code
        return [self.bic, 25, 5, '', '', '']

    def _set_sortcode(self, sortcode):
        self._sortcode = sortcode

    def _get_sortcode(self):
        return self._sortcode

    sortcode = property(_get_sortcode, _set_sortcode)

    def _set_bic(self, bic):
        if (not edifact_isalnum_size(bic, 8) and
                not edifact_isalnum_size(bic, 11)):
            raise ValueError("Account BIC/Swift code must be 8 or 11 "
                             "characters long: %s" % ustr(bic))
        self._bic = bic

    def _get_bic(self):
        return self._bic

    bic = property(_get_bic, _set_bic)

    def _set_number(self, number):
        if not edifact_digits(number, mindigits=1):
            raise ValueError("Account number is invalid: %s" %
                             ustr(number))

        self._number = number

    def _get_number(self):
        return self._number

    number = property(_get_number, _set_number)

    def __init__(self, number, holder, currency, sortcode, swiftcode, country,
                 origin_country=None, is_origin_account=False):
        self.origin_country = origin_country
        self.is_origin_account = is_origin_account
        self.number = number
        self.holder = holder
        self.currency = currency
        self.sortcode = sortcode
        self.country = country
        self.bic = swiftcode
        self.institution_identification = self._set_account_ident()


class IBANAccount(HasCurrency):
    def _get_iban(self):
        return self._iban

    def _set_iban(self, iban):
        iban_obj = sepa.IBAN(iban)
        if not iban_obj.valid:
            raise ValueError("IBAN is invalid: %s" % ustr(iban))

        self._iban = iban
        self.country = iban_obj.countrycode

    iban = property(_get_iban, _set_iban)

    def __init__(self, iban, bic, currency, holder):
        self.iban = iban
        self.number = iban
        self.bic = bic
        self.currency = currency
        self.holder = holder
        self.institution_identification = [self.bic, 25, 5, '', '', '']

    def fii_bf_segment(self):
        return _fii_segment(self, 'BF')


class Interchange(LogicalSection):
    def _get_reference(self):
        return self._reference

    def _set_reference(self, reference):
        if not len(reference) <= 15:
            raise ValueError("Reference must be <= 15 characters long: %s" %
                             ustr(reference))

        if not edifact_isalnum(reference):
            raise ValueError("Reference must be alphanumeric: %s" %
                             ustr(reference))

        self._reference = reference.upper()

    reference = property(_get_reference, _set_reference)

    def __init__(self, client_id, reference, create_dt=None, message=None):
        self.client_id = client_id
        self.create_dt = create_dt or datetime.datetime.now()
        self.reference = reference
        self.message = message

    def segments(self):
        segments = []
        segments.append([
            ['UNB'],
            ['UNOA', 3],
            ['', '', self.client_id],
            ['', '', 'HEXAGON ABC'],
            [self.create_dt.strftime('%y%m%d'),
             self.create_dt.strftime('%H%M')],
            [self.reference],
        ])
        segments += self.message.segments()
        segments.append([
            ['UNZ'],
            [1],
            [self.reference],
        ])
        return segments


class Message(LogicalSection):
    def _get_reference(self):
        return self._reference

    def _set_reference(self, reference):
        if not len(reference) <= 35:
            raise ValueError("Reference must be <= 35 characters long: %s" %
                             ustr(reference))

        if not edifact_isalnum(reference):
            raise ValueError("Reference must be alphanumeric: %s" %
                             ustr(reference))

        self._reference = reference.upper()

    reference = property(_get_reference, _set_reference)

    def __init__(self, reference, dt=None):
        if dt:
            self.dt = dt
        else:
            self.dt = datetime.datetime.now()

        self.reference = reference
        self.batches = []

    def segments(self):
        # HSBC only accepts one message per interchange
        message_reference_number = 1

        segments = []

        segments.append([
            ['UNH'],
            [message_reference_number],
            ['PAYMUL', 'D', '96A', 'UN', 'FUN01G'],
        ])
        segments.append([
            ['BGM'],
            [452],
            [self.reference],
            [9],
        ])
        segments.append([
            ['DTM'],
            (137, self.dt.strftime('%Y%m%d'), 102),
        ])
        for index, batch in enumerate(self.batches):
            segments += batch.segments(index + 1)
        segments.append([
            ['CNT'],
            ['39', sum([len(x.transactions) for x in self.batches])],
        ])
        segments.append([
            ['UNT'],
            [len(segments) + 1],
            [message_reference_number]
        ])

        return segments


class Batch(LogicalSection):
    def _get_reference(self):
        return self._reference

    def _set_reference(self, reference):
        if not len(reference) <= 18:
            raise ValueError("Reference must be <= 18 characters long: %s" %
                             ustr(reference))

        if not edifact_isalnum(reference):
            raise ValueError("Reference must be alphanumeric: %s" %
                             ustr(reference))

        self._reference = reference.upper()

    reference = property(_get_reference, _set_reference)

    def __init__(self, exec_date, reference, debit_account, name_address):
        self.exec_date = exec_date
        self.reference = reference
        self.debit_account = debit_account
        self.name_address = name_address
        self.transactions = []

    def amount(self):
        return sum([x.amount for x in self.transactions])

    def segments(self, index):
        if not edifact_digits(index, 6, 1):
            raise ValueError("Index must be 6 digits or less: " + str(index))

        # Store the payment means
        means = None
        if len(self.transactions) > 0:
            means = self.transactions[0].means

        segments = []

        if means != MEANS_PRIORITY_PAYMENT:
            segments.append([
                ['LIN'],
                [index],
            ])
            segments.append([
                ['DTM'],
                [203, self.exec_date.strftime('%Y%m%d'), 102],
            ])
            segments.append([
                ['RFF'],
                ['AEK', self.reference],
            ])

            currencies = set([x.currency for x in self.transactions])
            if len(currencies) > 1:
                raise ValueError("All transactions in a batch must have the "
                                 "same currency")

            segments.append([
                ['MOA'],
                [9, self.amount().quantize(Decimal('0.00')), currencies.pop()],
            ])
            segments.append(self.debit_account.fii_or_segment())
            segments.append([
                ['NAD'],
                ['OY'],
                [''],
                address_truncate(self.name_address),
            ])

        for index, transaction in enumerate(self.transactions):
            if transaction.means == MEANS_PRIORITY_PAYMENT:
                # Need a debit-credit format for Priority Payments
                segments.append([
                    ['LIN'],
                    [index + 1],
                ])
                segments.append([
                    ['DTM'],
                    [203, self.exec_date.strftime('%Y%m%d'), 102],
                ])
                segments.append([
                    ['RFF'],
                    ['AEK', self.reference],
                ])

                # Use the transaction amount and currency for the debit line
                segments.append([
                    ['MOA'],
                    [9, transaction.amount.quantize(Decimal('0.00')),
                     transaction.currency],
                ])
                segments.append(self.debit_account.fii_or_segment())
                segments.append([
                    ['NAD'],
                    ['OY'],
                    [''],
                    address_truncate(self.name_address),
                ])
                use_index = 1
            else:
                use_index = index + 1

            segments += transaction.segments(use_index)

        return segments

# From the spec for FCA segments:
# 13 = All charges borne by payee (or beneficiary)
# 14 = Each pay own cost
# 15 = All charges borne by payor (or ordering customer)
# For Faster Payments this should always be ‘14’
# Where this field is not present, “14” will be used as a default.
CHARGES_PAYEE = 13
CHARGES_EACH_OWN = 14
CHARGES_PAYER = 15

# values per section 2.8.5 "PAI, Payment Instructions" of
# "HSBC - CRG Paymul Message Implementation Guide"
MEANS_ACH_OR_EZONE = 2
MEANS_PRIORITY_PAYMENT = 52
MEANS_FASTER_PAYMENT = 'FPS'

CHANNEL_INTRA_COMPANY = 'Z24'


class Transaction(LogicalSection, HasCurrency):
    def _get_amount(self):
        return self._amount

    def _set_amount(self, amount):
        if len(str(amount)) > 18:
            raise ValueError("Amount must be shorter than 18 bytes: %s" %
                             ustr(amount))

        self._amount = amount

    amount = property(_get_amount, _set_amount)

    def _get_payment_reference(self):
        return self._payment_reference

    def _set_payment_reference(self, payment_reference):
        if not len(payment_reference) <= 18:
            raise ValueError(
                "Payment reference must be <= 18 characters long: %s" %
                ustr(payment_reference)
            )

        if not edifact_isalnum(payment_reference):
            raise ValueError("Payment reference must be alphanumeric: %s" %
                             ustr(payment_reference))

        self._payment_reference = payment_reference.upper()

    payment_reference = property(
        _get_payment_reference, _set_payment_reference
    )

    def _get_customer_reference(self):
        return self._customer_reference

    def _set_customer_reference(self, customer_reference):
        if not len(customer_reference) <= 18:
            raise ValueError(
                "Customer reference must be <= 18 characters long: %s" %
                ustr(customer_reference)
            )

        if not edifact_isalnum(customer_reference):
            raise ValueError("Customer reference must be alphanumeric: %s" %
                             ustr(customer_reference))

        self._customer_reference = customer_reference.upper()

    customer_reference = property(
        _get_customer_reference,
        _set_customer_reference
    )

    def __init__(self, amount, currency, account, means,
                 name_address=None, party_name=None, channel='',
                 charges=CHARGES_EACH_OWN, customer_reference=None,
                 payment_reference=None):
        self.amount = amount
        self.currency = currency
        self.account = account
        self.name_address = name_address
        self.party_name = party_name
        self.means = means
        self.channel = channel
        self.charges = charges
        self.payment_reference = payment_reference
        self.customer_reference = customer_reference

    def segments(self, index):
        segments = []
        segments.append([
            ['SEQ'],
            [''],
            [index],
        ])
        segments.append([
            ['MOA'],
            [9, self.amount.quantize(Decimal('0.00')), self.currency],
        ])

        if self.customer_reference:
            segments.append([
                ['RFF'],
                ['CR', self.customer_reference],
            ])

        if self.payment_reference:
            segments.append([
                ['RFF'],
                ['PQ', self.payment_reference],
            ])

        if self.channel:
            segments.append([
                ['PAI'],
                ['', '', self.means, '', '', self.channel],
            ])
        else:
            segments.append([
                ['PAI'],
                ['', '', self.means],
            ])

        segments.append([
            ['FCA'],
            [self.charges],
        ])

        segments.append(self.account.fii_bf_segment())

        nad_segment = [
            ['NAD'],
            ['BE'],
            [''],
        ]
        if self.name_address:
            nad_segment.append(address_truncate(self.name_address))
        else:
            nad_segment.append('')
        if self.party_name:
            nad_segment.append(address_truncate(self.party_name))
        segments.append(nad_segment)

        return segments