Fattura Elettronica and Python playground

canoninvoice.py

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
#
# 2019-2021 - Marco Trevisan
#
# Fattura Elettronica and python Playground
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU 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 General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

import calendar
import datetime
import xml.etree.cElementTree as ET
import xml.dom.minidom
from enum import Enum

class ITElectronicInvoice(object):
    '''Spec at https://www.fatturapa.gov.it/export/documenti/Specifiche_tecniche_del_formato_FatturaPA_V1.3.1.pdf'''

    BASE_XML = '''<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ns2:FatturaElettronica versione="FPR12" xmlns:ns2="http://ivaservizi.agenziaentrate.gov.it/docs/xsd/fatture/v1.2">
</ns2:FatturaElettronica>
'''

    class Regime(Enum):
        ORDINARY = 'RF01' # Ordinario
        MINIMUM_CONTRIBUTORS = 'RF02' # Contribuenti minimi (art.1, c.96-117, L. 244/07)
        NEW_VENTURES = 'RF03' # Nuove iniziative produttive (art.13, L. 388/00)
        AGRICULTURE_FISHING = 'RF04' # Agricoltura e attività connesse e pesca (artt.34 e 34-bis, DPR 633/72)
        TOBACCO_SELL = 'RF05' # Vendita sali e tabacchi (art.74, c.1, DPR. 633/72)
        MATCHSTICK_TRADING = 'RF06' # Commercio fiammiferi (art.74, c.1, DPR 633/72)
        EDITORS = 'RF07' # Editoria (art.74, c.1, DPR 633/72)
        PUBLIC_TELEPHONY = 'RF08' # Gestione servizi telefonia pubblica (art.74, c.1, DPR 633/72)
        PUBLIC_TRANSPORT = 'RF09' # Rivendita documenti di trasporto pubblico e di sosta (art.74, c.1, DPR 633/72)
        GAMING = 'RF10' # Intrattenimenti, giochi e altre attività di cui alla tariffa allegata al DPR 640/72 (art.74, c.6, DPR 633/72)
        TRAVEL_AGENTS = 'RF11' # Agenzie viaggi e turismo (art.74-ter, DPR 633/72)
        AGRITURISM = 'RF12' # Agriturismo (art.5, c.2, L. 413/91)
        HOME_DELIVERY = 'RF13' # Vendite a domicilio (art.25-bis, c.6, DPR 600/73)
        SECONDHAND_SELL = 'RF14' # Rivendita beni usati, oggetti d’arte, d’antiquariato o da collezione (art.36, DL 41/95)
        BID_AUCTION = 'RF15' # Agenzie di vendite all’asta di oggetti d’arte, antiquariato o da collezione (art.40-bis, DL 41/95)
        PUBLIC_ADMINISTRATION_CASH_ACCOUNTING = 'RF16' # IVA per cassa P.A. (art.6, c.5, DPR 633/72)
        CASH_ACCOUNTING = 'RF17' # IVA per cassa (art. 32-bis, DL 83/2012)
        OTHER = 'RF18' # Altro
        FLAT_REGIME = 'RF19' # Regime forfettario (art.1, c.54-89, L. 190/2014)

    class TaxType(Enum):
        NORMAL = None
        EXCLUDED_ART_15 = 'N1'
        # NOT_APPLIED = 'N2'
        NOT_APPLIED_DPR_633_72 = 'N2.1'
        NOT_APPLIED_OTHERS = 'N2.2'
        # NOT_APPLIABLE = 'N3'
        NOT_APPLIABLE_EXPORT = 'N3.1'
        NOT_APPLIABLE_TRANSFER_EU = 'N3.2'
        NOT_APPLIABLE_SAN_MARINO = 'N3.3'
        NOT_APPLIABLE_TRANSFER_EXPORT = 'N3.4'
        NOT_APPLIABLE_INTENT = 'N3.5'
        NOT_APPLIABLE_OTHERS = 'N3.6'
        EXEMPT = 'N4'
        MARGIN_REGIME = 'N5'
        # REVERSE_CHARGE = 'N6'
        REVERSE_CHARGE_N6_1 = 'N6.1'
        REVERSE_CHARGE_N6_2 = 'N6.2'
        REVERSE_CHARGE_N6_3 = 'N6.3'
        REVERSE_CHARGE_N6_4 = 'N6.4'
        REVERSE_CHARGE_N6_5 = 'N6.5'
        REVERSE_CHARGE_N6_6 = 'N6.6'
        REVERSE_CHARGE_N6_7 = 'N6.7'
        REVERSE_CHARGE_N6_8 = 'N6.8'
        REVERSE_CHARGE_N6_9 = 'N6.9'

    class PensionType(Enum):
        LAWYERS = 'TC01'
        ACCOUNTANTS = 'TC02'
        SURVEYORS = 'TC03'
        ENGINEERS_AND_ARCHITECTS = 'TC04'
        NOTARIES = 'TC05'
        COMMERCIAL_ACCOUNTANTS = 'TC06'
        ENASARCO = 'TC07'
        ENPACL = 'TC08'
        ENPAM = 'TC09'
        ENPAF = 'TC10'
        ENPAV = 'TC11'
        ENPAIA = 'TC12'
        POSTMEN = 'TC13'
        INPGI = 'TC14'
        ONAOSI = 'TC15'
        CASAGIT = 'TC16'
        EPPI = 'TC17'
        EPAP = 'TC18'
        ENPAB = 'TC19'
        ENPAPI = 'TC20'
        ENPAP = 'TC21'
        INPS = 'TC22'

    class PaymentCondition(Enum):
        INSTALLMENTS = 'TP01'
        FULL = 'TP02'
        PREPAID = 'TP03'

    class PaymentMode(Enum):
        CASH = 'MP01'
        CHECK = 'MP02'
        CASHIER_CHECK = 'MP03'
        CONTANTI_PRESSO_TESORERIA = 'MP04'
        BANK_TRANSFER = 'MP05'
        VAGLIA_CAMBIARIO = 'MP06'
        BOLLETTINO_BANCARIO = 'MP07'
        CREDIT_CARD = 'MP08'
        RID = 'MP09'
        RID_UTENZE = 'MP10'
        RID_VELOCE = 'MP11'
        RIBA = 'MP12'
        MAV = 'MP13'
        QUIETANZA_ERARIO_STATO = 'MP14'
        GIROCONTO_SU_CONTI_DI_CONTABILITÀ_SPECIALE = 'MP15'
        DOMICILIAZIONE_BANCARIA = 'MP16'
        DOMICILIAZIONE_POSTALE = 'MP17'


    class Address(object):
        def __init__(self, street, no, zip_code, city, province, country_id):
            self.Indirizzo = street
            self.NumeroCivico = no
            self.CAP = zip_code
            self.Comune = city
            self.Provincia = province
            self.Nazione = country_id

    class Contacts(object):
        def __init__(self, email, phone=None):
            self.Telefono = phone
            self.Email = email

    class FiscalContacts(object):
        def __init__(self, country_id, vat_no):
            self.IdPaese = country_id
            self.IdCodice = vat_no

    class Business(object):
        def __init__(self, country_id, vat_no, nin, regime, name, address, contacts=None):
            self.DatiAnagrafici = {
                'IdFiscaleIVA': ITElectronicInvoice.FiscalContacts(country_id, vat_no),
                'CodiceFiscale': nin,
                'Anagrafica': {
                    'Denominazione': name
                },
                'RegimeFiscale': regime,
            }
            self.Sede = address
            self.Contatti = contacts

    class Pension(object):
        def __init__(self, pension_type, amount, rate, vat=22, tax_type=None):
            self.TipoCassa = pension_type
            self.AlCassa = float(rate)
            self.ImportoContributoCassa = float(amount)
            self.AliquotaIVA = float(vat)
            self.Natura = tax_type

    class PaymentDetails(object):
        def __init__(self, beneficiary, payment_mode, amount, iban, date_limit,
                     abi=None, cab=None, bic=None, institute=None):
            assert payment_mode == ITElectronicInvoice.PaymentMode.BANK_TRANSFER
            self.Beneficiario = beneficiary
            self.ModalitaPagamento = payment_mode
            self.DataScadenzaPagamento = date_limit
            self.ImportoPagamento = float(amount)
            self.IstitutoFinanziario = institute
            self.IBAN = iban
            self.ABI = int(abi) if abi else None
            self.CAB = int(cab) if cab else None
            self.BIC = bic

    class Item(object):
        def __init__(self, description, amount, vat=22, tax_type=None,
                     start=None, end=None, number=1):
            self.Descrizione = description
            self.DataInizioPeriodo = start
            self.DataFinePeriodo = end
            self.PrezzoUnitario = float(amount)
            self.PrezzoTotale = float(amount * number)
            self.AliquotaIVA = float(vat)
            self.Natura = tax_type


    def __init__(self, id, date, sender, emitter, receiver, receiver_code, receiver_pec=None):
        self.fe = ET.fromstring(ITElectronicInvoice.BASE_XML)
        self.id = id
        self.date = date
        self.sender = sender
        self.emitter = emitter
        self.receiver = receiver
        self.receiver_code = receiver_code
        self.receiver_pec = receiver_pec
        self.items = []
        self.tax_rules = {}
        self.beni = None
        self.pension = None
        self.payment = None

    def add_item(self, item):
        if item.PrezzoTotale != 0:
            self.items.append(item)
            return item

    def add_expense(self, amount, reason):
        self.add_item(ITElectronicInvoice.Item(reason, amount, vat=0,
            tax_type=ITElectronicInvoice.TaxType.EXCLUDED_ART_15))

    def set_pension(self, description, pension_type, amount, rate, vat, tax_type):
        item = self.add_item(ITElectronicInvoice.Item(description, amount,
            vat=vat, tax_type=tax_type))
        self.pension = ITElectronicInvoice.Pension(pension_type, amount, rate,
            vat, tax_type)
        self.pension._item = item

    def set_payment_details(self, conditions, details):
        self.payment = {
            'CondizioniPagamento': conditions,
            'DettaglioPagamento': details,
        }

    def _xmlfy_obj(self, parent, d):
        if isinstance(d, Enum):
            self._xmlfy_obj(parent, d.value)
        elif isinstance(d, dict):
            p = None
            for k, v in d.items():
                if v is None:
                    continue
                p = ET.SubElement(parent, k)
                if isinstance(v, tuple) or isinstance(v, list):
                    for vv in v:
                        self._xmlfy_obj(p, vv)
                else:
                    self._xmlfy_obj(p, v)
            if len(d.items()) == 1 and p != None:
                parent = p
        elif isinstance(d, tuple) or isinstance(d, list):
            p = ET.SubElement(parent, parent.tag)
            for v in d:
                self._xmlfy_obj(p, v)
        elif isinstance(d, object) and hasattr(d, '__dict__'):
            self._xmlfy_obj(parent, { k: v for k, v in d.__dict__.items()
                if not k.startswith('_') })
        elif isinstance(d, float):
            parent.text = '{0:.2f}'.format(round(d, 2))
        elif isinstance(d, datetime.datetime):
            parent.text = '{:%Y-%m-%d}'.format(d)
        else:
            parent.text = str(d)
        return parent

    def _build_header(self):
        return self._xmlfy_obj(self.fe, {
            'FatturaElettronicaHeader': {
                'DatiTrasmissione': {
                    'IdTrasmittente': self.sender,
                    'ProgressivoInvio': 1,
                    'FormatoTrasmissione': 'FPR12',
                    'CodiceDestinatario': self.receiver_code,
                    'PECDestinatario': self.receiver_pec
                },
                'CedentePrestatore': self.emitter,
                'CessionarioCommittente': self.receiver,
            }
        })

    def _build_body(self):
        body = self._xmlfy_obj(self.fe, {
            'FatturaElettronicaBody': {
                'DatiGenerali': {
                    'DatiGeneraliDocumento': {
                        'TipoDocumento': 'TD01',
                        'Divisa': 'EUR',
                        'Data': self.date,
                        'Numero': self.id,
                        'DatiCassaPrevidenziale': self.pension,
                        'ImportoTotaleDocumento': self.total_amount(),
                    }
                }
            }
        })

        if len(self.items):
            self.beni = self._xmlfy_obj(body, { 'DatiBeniServizi': [] })

        self._xmlfy_obj(body, {'DatiPagamento': self.payment})
        return body

    def total_amount(self):
        return sum([x.PrezzoTotale for x in self.items])

    def _compute_amount_by_tax(self, tax_type):
        return sum([x.PrezzoTotale for x in self.items if x.Natura == tax_type])

    def _add_items(self):
        idx = 1

        for item in self.items:
            if self.pension and self.pension._item == item:
                continue
            detail = self._xmlfy_obj(self.beni, {
                'DettaglioLinee': {
                    'NumeroLinea': idx,
                }
            })
            self._xmlfy_obj(detail, item)
            idx += 1

    def _add_summary_line(self, kind, amount, vat_percent=0, vat=0):
        if amount <= 0:
            return None

        return self._xmlfy_obj(self.beni, {
            'DatiRiepilogo': {
                'AliquotaIVA': float(vat_percent),
                'Natura': kind,
                'ImponibileImporto': float(amount),
                'Imposta': float(vat),
            }
        })

    def _compute_tax_summary(self):
        for tax_type in ITElectronicInvoice.TaxType:
            summary = self._add_summary_line(tax_type,
                self._compute_amount_by_tax(tax_type))

            if tax_type in self.tax_rules:
                self._xmlfy_obj(summary,
                    { 'RiferimentoNormativo': self.tax_rules[tax_type] })

    def generate(self, path):
        self._build_header()
        self._build_body()

        self._add_items()
        self._compute_tax_summary()

        with open(path, 'w') as file:
            xmlstr = ET.tostring(self.fe, encoding='unicode', method='xml')
            pretty = xml.dom.minidom.parseString(xmlstr).toprettyxml(indent='    ')
            xmlstr = '\n'.join(list(filter(lambda x: len(x.strip()), pretty.split('\n'))))
            file.write(xmlstr)


class CanonicalInvoice(ITElectronicInvoice):
    def __init__(self, id, date, amount, sender, emitter):
        canonical = ITElectronicInvoice.Business('GB', '003232247', None, None,
            'Canonical Services Limited', ITElectronicInvoice.Address(
                '991TT, Finch Road', '12-14', '00000', 'Douglas', None, 'IM'))

        super().__init__(id, date, sender, emitter, canonical, receiver_code='XXXXXXX')

        self.first_day = datetime.date(year=date.year, month=date.month, day=1)
        self.last_day = datetime.date(year=date.year, month=date.month,
            day=calendar.monthrange(date.year, date.month)[1])

        description = 'Development in {} {}'.format('{:%B}'.format(date), date.year)
        self.add_item(ITElectronicInvoice.Item(description, amount, vat=0,
                start=self.first_day, end=self.last_day,
                tax_type=ITElectronicInvoice.TaxType.NOT_APPLIED_DPR_633_72))

        self.tax_rules[ITElectronicInvoice.TaxType.NOT_APPLIED_DPR_633_72] = \
            'art. 7, DPR 633/72 - Operazione di prestazione di servizi non soggetta'

    def add_bonus(self, amount, reason):
        self.add_item(ITElectronicInvoice.Item(reason, amount, vat=0,
            tax_type=ITElectronicInvoice.TaxType.NOT_APPLIED_DPR_633_72))

    def add_expense(self, amount, reason):
        super().add_expense(amount, reason)

        if amount > 0:
            print('Remember to attach the Expensify PDF for `{}` when '
                'uploading the invoice'.format(
                    reason if len(reason) else 'the {} expense'.format(amount)))


if __name__ == "__main__":

    vat_no = '012345678901'
    me_person = ITElectronicInvoice.FiscalContacts('IT', 'TRVMRC12B345678Z')
    me = ITElectronicInvoice.Business('IT', vat_no, me_person.IdCodice,
        ITElectronicInvoice.Regime.ORDINARY, 'SiProgramma.it',
        ITElectronicInvoice.Address('Via lì', 2, 12345, 'Laggiù', 'FI', 'IT'),
            ITElectronicInvoice.Contacts('foo@bar.baz', '3287654321'))

    id = 321
    date = datetime.datetime.now()
    total_amount = 10000000
    bonus = 5000
    pension_revenge_rate = 4.0
    expense = 3000

    amount = ((total_amount - expense) / (1.0 + pension_revenge_rate/100)) - bonus
    inps = total_amount - amount - bonus - expense

    fe = CanonicalInvoice(id, date, amount, me_person, me)
    fe.add_expense(expense/2, 'Alcool')
    fe.add_expense(expense/2, 'Fun')
    fe.add_bonus(bonus, 'Super spotlight prize')
    fe.set_pension('Rivalsa INPS 4% (national insurance)',
        ITElectronicInvoice.PensionType.INPS, inps,
        rate=pension_revenge_rate, vat=0,
        tax_type=ITElectronicInvoice.TaxType.NOT_APPLIED_DPR_633_72)
    fe.set_payment_details(ITElectronicInvoice.PaymentCondition.FULL,
        ITElectronicInvoice.PaymentDetails('Marco Trevisan',
            ITElectronicInvoice.PaymentMode.BANK_TRANSFER,
            amount=total_amount, date_limit=date,
            iban='ES6621000418401234567891', institute='Caixa bank'))

    path = '/tmp/IT{}_draft.xml'.format(vat_no)
    fe.generate(path)

    print('File saved as', path)