from django.db import models
from django.utils.translation import gettext_lazy as _

from .forms import BICFormField, IBANFormField
from .validators import BICValidator, IBANValidator


class IBANField(models.CharField):
    """
    An IBAN consists of up to 34 alphanumeric characters.

    To limit validation to specific countries, set the 'include_countries' argument with a tuple or list of ISO 3166-1
    alpha-2 codes. For example, `include_countries=('NL', 'BE, 'LU')`.

    A list of countries that use IBANs as part of SEPA is included for convenience. To use this feature, set
    `include_countries=IBAN_SEPA_COUNTRIES` as an argument to the field.

    Example:

    .. code-block:: python

        from django.db import models
        from localflavor.generic.models import IBANField
        from localflavor.generic.countries.sepa import IBAN_SEPA_COUNTRIES

        class MyModel(models.Model):
            iban = IBANField(include_countries=IBAN_SEPA_COUNTRIES)

    In addition to validating official IBANs, this field can optionally validate unofficial IBANs that have been
    catalogued by Nordea by setting the `use_nordea_extensions` argument to True.

    https://en.wikipedia.org/wiki/International_Bank_Account_Number

    .. versionadded:: 1.1
    """

    description = _('An International Bank Account Number')

    def __init__(self, *args, **kwargs):
        kwargs.setdefault('max_length', 34)
        self.use_nordea_extensions = kwargs.pop('use_nordea_extensions', False)
        self.include_countries = kwargs.pop('include_countries', None)
        super().__init__(*args, **kwargs)
        self.validators.append(IBANValidator(self.use_nordea_extensions, self.include_countries))

    def deconstruct(self):
        name, path, args, kwargs = super().deconstruct()
        kwargs['use_nordea_extensions'] = self.use_nordea_extensions
        kwargs['include_countries'] = self.include_countries
        return name, path, args, kwargs

    def to_python(self, value):
        value = super().to_python(value)
        if value is not None:
            return value.upper().replace(' ', '').replace('-', '')
        return value

    def formfield(self, **kwargs):
        defaults = {
            'use_nordea_extensions': self.use_nordea_extensions,
            'include_countries': self.include_countries,
            'form_class': IBANFormField,
        }
        defaults.update(kwargs)
        return super().formfield(**defaults)


class BICField(models.CharField):
    """
    A BIC consists of 8 (BIC8) or 11 (BIC11) alphanumeric characters.

    BICs are also known as SWIFT-BIC, BIC code, SWIFT ID, SWIFT code or ISO 9362.

    https://en.wikipedia.org/wiki/ISO_9362

    .. versionadded:: 1.1
    """

    description = _('Business Identifier Code')

    def __init__(self, *args, **kwargs):
        kwargs.setdefault('max_length', 11)
        super().__init__(*args, **kwargs)
        self.validators.append(BICValidator())

    def to_python(self, value):
        # BIC is always written in upper case.
        # https://www2.swift.com/uhbonline/books/public/en_uk/bic_policy/bic_policy.pdf
        value = super().to_python(value)
        if value is not None:
            return value.replace(' ', '').upper()
        return value

    def formfield(self, **kwargs):
        defaults = {'form_class': BICFormField}
        defaults.update(kwargs)
        return super().formfield(**defaults)