from datetime import datetime
from dateutil.relativedelta import relativedelta

from django import forms
from django.utils.translation import gettext_lazy as _

from .models import RoadAuthorization, RoadAuthorizationDocument, RoadAuthorizationDate

# Default initial datetime for occupation dates: next month
_DEFAULT_DATE = lambda: (datetime.today() + relativedelta(months=1)).strftime('%Y-%m-%d')


class AuthorizationForm(forms.ModelForm):
    """Main authorization request form – no crispy forms dependency."""

    class Meta:
        model = RoadAuthorization
        fields = (
            'language',
            'type',
            'description',
            'location',
            'applicant_name',
            'applicant_email',
            'applicant_address',
            'applicant_enterprise',
        )
        widgets = {
            'type': forms.RadioSelect(attrs={'class': 'btn-check', 'autocomplete': 'off'}),
            'language': forms.RadioSelect(attrs={'class': 'btn-check', 'autocomplete': 'off'}),
        }

    # Hidden field that receives the GeoJSON polygon drawn on the MapLibre map.
    # The view converts it to a MultiPolygonField before saving.
    geom_geojson = forms.CharField(
        widget=forms.HiddenInput(),
        required=True,
        label='',
    )

    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        # Remove the blank "-------" choice Django injects when there is no default value
        self.fields['type'].choices = [
            (k, v) for k, v in self.fields['type'].choices if k != ''
        ]
        self.fields['language'].choices = [
            (k, v) for k, v in self.fields['language'].choices if k != ''
        ]
        self.fields['description'].widget.attrs.update({'class': 'form-control', 'rows': 5})
        self.fields['location'].widget.attrs.update({'class': 'form-control'})
        self.fields['applicant_name'].widget.attrs.update({'class': 'form-control'})
        self.fields['applicant_email'].widget.attrs.update({'class': 'form-control'})
        self.fields['applicant_address'].widget.attrs.update({'class': 'form-control'})
        self.fields['applicant_enterprise'].widget.attrs.update({'class': 'form-control'})

    def clean_geom_geojson(self):
        """Validate that the submitted GeoJSON is a valid polygon."""
        import json
        value = self.cleaned_data.get('geom_geojson', '').strip()
        if not value:
            raise forms.ValidationError(_("Veuillez dessiner la zone concernée sur la carte."))
        try:
            geom = json.loads(value)
        except (ValueError, TypeError):
            raise forms.ValidationError(_("Géométrie invalide."))
        if geom.get('type') not in ('Polygon', 'MultiPolygon'):
            raise forms.ValidationError(_("Veuillez dessiner un polygone."))
        return value


class AuthorizationDocumentForm(forms.ModelForm):
    class Meta:
        model = RoadAuthorizationDocument
        fields = ('description', 'file')
        widgets = {
            'description': forms.TextInput(attrs={'class': 'form-control', 'placeholder': _('Description du document')}),
            'file': forms.ClearableFileInput(attrs={'class': 'form-control'}),
        }


AuthorizationDocumentFormSet = forms.inlineformset_factory(
    RoadAuthorization,
    RoadAuthorizationDocument,
    form=AuthorizationDocumentForm,
    extra=1,
    can_delete=False,
)


class AuthorizationDateForm(forms.ModelForm):
    class Meta:
        model = RoadAuthorizationDate
        fields = ('begin_date', 'end_date')
        widgets = {
            'begin_date': forms.DateTimeInput(
                attrs={
                    'type': 'datetime-local',
                    'class': 'form-control',
                }
            ),
            'end_date': forms.DateTimeInput(
                attrs={
                    'type': 'datetime-local',
                    'class': 'form-control',
                }
            ),
        }

    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.fields['end_date'].required = False


AuthorizationDateFormSet = forms.inlineformset_factory(
    RoadAuthorization,
    RoadAuthorizationDate,
    form=AuthorizationDateForm,
    extra=1,
    can_delete=False,
)


class AuthorizationFilterForm(forms.Form):
    """Filter form used on the staff list view."""
    include_archives = forms.BooleanField(
        label=_("Inclure les archives (> 2 ans)"),
        required=False,
        widget=forms.CheckboxInput(attrs={'class': 'form-check-input'}),
    )
    authorization_type = forms.MultipleChoiceField(
        label=_("Type d'autorisation"),
        choices=RoadAuthorization.AUTH_TYPE,
        widget=forms.CheckboxSelectMultiple(attrs={'class': 'form-check-input'}),
        required=False,
    )
    search_text = forms.CharField(
        max_length=250,
        required=False,
        widget=forms.TextInput(attrs={'class': 'form-control', 'placeholder': _('Recherche…')}),
    )