from django import forms
from django.core.exceptions import ValidationError
from django.utils.translation import ugettext_lazy as _

from orchestra.admin.forms import AdminFormSet

from . import validators
from .helpers import domain_for_validation
from .models import Domain


class BatchDomainCreationAdminForm(forms.ModelForm):
    name = forms.CharField(label=_("Names"), widget=forms.Textarea(attrs={'rows': 5, 'cols': 50}),
        help_text=_("Fully qualified domain name per line. "
                    "All domains will have the provided account and records."))
    
    def clean_name(self):
        self.extra_names = []
        target = None
        existing = set(Domain.objects.values_list('name', flat=True))
        errors = []
        for name in self.cleaned_data['name'].strip().splitlines():
            name = name.strip()
            if not name:
                continue
            if name in existing:
                 errors.append(ValidationError(_("%s domain name already exists.") % name))
            existing.add(name)
            if target is None:
                target = name
            else:
                domain = Domain(name=name)
                try:
                    domain.full_clean(exclude=['top'])
                except ValidationError as e:
                    raise ValidationError(e.error_dict['name'])
                self.extra_names.append(name)
        if errors:
            raise ValidationError(errors)
        return target
    
    def clean(self):
        """ inherit related parent domain account, when exists """
        cleaned_data = super(BatchDomainCreationAdminForm, self).clean()
        if not cleaned_data['account']:
            account = None
            for name in [cleaned_data['name']] + self.extra_names:
                parent = Domain.get_parent_domain(name)
                if not parent:
                    # Fake an account to make django validation happy
                    account_model = self.fields['account']._queryset.model
                    cleaned_data['account'] = account_model()
                    raise ValidationError({
                        'account': _("An account should be provided for top domain names."),
                    })
                elif account and parent.account != account:
                    # Fake an account to make django validation happy
                    account_model = self.fields['account']._queryset.model
                    cleaned_data['account'] = account_model()
                    raise ValidationError({
                        'account': _("Provided domain names belong to different accounts."),
                    })
                account = parent.account
                cleaned_data['account'] = account
        return cleaned_data


class RecordForm(forms.ModelForm):
    class Meta:
        fields = ('ttl', 'type', 'value')
    
    def __init__(self, *args, **kwargs):
        super(RecordForm, self).__init__(*args, **kwargs)
        self.fields['ttl'].widget = forms.TextInput(attrs={'size':'10'})
        self.fields['value'].widget = forms.TextInput(attrs={'size':'100'})


class ValidateZoneMixin(object):
    def clean(self):
        """ Checks if everything is consistent """
        super(ValidateZoneMixin, self).clean()
        if any(formset.errors):
            return
        if formset.instance.name:
            records = []
            for form in formset.forms:
                data = form.cleaned_data
                if data and not data['DELETE']:
                    records.append(data)
            domain = domain_for_validation(formset.instance, records)
            validators.validate_zone(domain.render_zone())


class RecordEditFormSet(ValidateZoneMixin, AdminFormSet):
    pass


class RecordInlineFormSet(ValidateZoneMixin, forms.models.BaseInlineFormSet):
    pass