from django.conf import settings
from django.forms import ModelForm, ChoiceField, RadioSelect, BooleanField, CharField, EmailField
from django.contrib.admin.widgets import AdminDateWidget
from django.forms.renderers import DjangoTemplates
from django.utils.html import format_html
from django.utils.safestring import mark_safe
from django import forms

from .models import (
    TYPE_CHOICES,
    Project,
    ConcreteVolunteer,
    ConcreteExtern,
    IFG,
    Library,
    ELiterature,
    Software,
    HonoraryCertificate,
    Travel,
    Email,
    Literature,
    List,
    BusinessCard,
)


class TableFormRenderer(DjangoTemplates):
    form_template_name = 'django/forms/table.html'


class FdbForm(ModelForm):
    '''this base class provides the required css class for all forms'''
    required_css_class = 'required'


class ProjectForm(FdbForm):
    # start = DateField(widget=AdminDateWidget())

    class Meta:
        model = Project
        exclude = ('pid', 'project_of_year', 'finance_id', 'granted', 'granted_date', 'realname', 'email', \
                   'end_mail_send', 'status', 'persons', 'survey_mail_date', 'mail_state')
        widgets = {'start': AdminDateWidget(),
                   'end': AdminDateWidget(), }

    class Media:
        js = ('dropdown/js/otrs_link.js',)


class CommonOrderMixin(forms.Form):
    """
    Ensures a consistent field order for all forms that inherit from this mixin.

    The goal is to always render:
      - "realname" and "email" fields at the top,
      - all other fields in the middle (in the order Django provides),
      - "check" (terms/privacy checkbox) at the bottom.

    This keeps the UX consistent across all forms without repeating field_order logic.
    """

    # Fields that should always appear first in the form
    field_order_head = ('realname', 'email')

    # Fields that should always appear last in the form
    field_order_tail = ('check',)  # rename if your checkbox field is called differently

    def __init__(self, *args, **kwargs):
        """
        Override the default form initialization to reorder fields.
        The method:
          1. Collects all existing field names.
          2. Puts the 'head' fields first (if they exist in this form).
          3. Keeps all other fields in the middle.
          4. Puts the 'tail' fields last (if they exist in this form).
        """
        super().__init__(*args, **kwargs)

        existing = list(self.fields.keys())

        # Select only fields that actually exist in this form
        head = [f for f in self.field_order_head if f in self.fields]
        tail = [f for f in self.field_order_tail if f in self.fields]

        # All other fields that are not explicitly in head or tail
        middle = [f for f in existing if f not in (*head, *tail)]

        # Apply the new order to the form fields
        self.order_fields(head + middle + tail)


class ExternForm(FdbForm):

    choice = ChoiceField(choices=TYPE_CHOICES.items(), widget=RadioSelect,
                         label='Was möchtest Du beantragen?')

    check = BooleanField(required=True,
                         label=format_html("Ich stimme den <a href='{}' target='_blank' rel='noopener'>Datenschutzbestimmungen</a> und der<br> <a href='{}' target='_blank' rel='noopener'>Richtlinie zur Förderung der Communitys</a> zu",
                         settings.DATAPROTECTION, settings.FOERDERRICHTLINIEN))

    class Meta:
        model = ConcreteExtern
        exclude = ('username', 'granted', 'granted_date', 'survey_mail_send', 'service_id', 'survey_mail_date', 'mail_state')


INTERN_CHOICES = {'PRO': 'Projektsteckbrief',
                  'HON': 'Ehrenamtsbescheinigung, Akkreditierung oder Redaktionsbestätigung',
                  'TRAV': 'Reisekostenerstattung'}

class InternForm(FdbForm):
    choice = ChoiceField(choices = INTERN_CHOICES.items(), widget=RadioSelect,
                         label = 'Was möchtest Du eingeben?')

    class Meta:
        model = ConcreteVolunteer
        exclude = ('granted', 'granted_date', 'survey_mail_send', 'survey_mail_date', 'mail_state')


HOTEL_CHOICES = {'TRUE': mark_safe('Hotelzimmer benötigt'),
                 'FALSE': mark_safe('Kein Hotelzimmer benötigt')
                 }


class BaseApplicationForm(FdbForm):
    """
    Base form for all external applications.

    - Adds standard fields that must appear in every form:
      * realname (applicant's full name)
      * email (contact address for notifications)
      * check (confirmation of data protection and funding policy)
    - Ensures consistency across all application types.
    """
    realname = CharField(
        label="Realname",
        required=True,
        help_text="Bitte gib deinen Vor- und Nachnamen ein."
    )
    email = EmailField(
        label="E-Mail-Adresse",
        required=True,
        help_text="Bitte gib deine E-Mail-Adresse ein, damit dich <br> Wikimedia Deutschland bei Rückfragen oder für <br> die Zusage kontaktieren kann."
    )
    check = BooleanField(required=True,
                         label=format_html(
                             "Ich stimme den <a href='{}' target='_blank' rel='noopener'>Datenschutzbestimmungen</a> und der<br> <a href='{}' target='_blank' rel='noopener'>Richtlinie zur Förderung der Communitys</a> zu",
                             settings.DATAPROTECTION, settings.FOERDERRICHTLINIEN))


class TravelForm(BaseApplicationForm, CommonOrderMixin):
    # TODO: add some javascript to show/hide other-field

    # this is the code, to change required to false if needed
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.fields['project_name'].required = True
        self.fields['transport'].required = True
        self.fields['travelcost'].required = True
        self.fields['checkin'].required = True
        self.fields['checkout'].required = True
        self.fields['hotel'].required = True

    class Meta:
        model = Travel
        exclude = ('granted', 'granted_date', 'survey_mail_send', 'realname', 'email', 'survey_mail_date', 'project', 'request_url', 'payed_for_hotel_by', 'payed_for_travel_by', 'intern_notes', 'mail_state' )
        widgets = {'checkin': AdminDateWidget(),
                   'checkout': AdminDateWidget(),}
        fields = ['project_name', 'transport', 'travelcost', 'checkin', 'checkout', 'hotel', 'notes']
    hotel = ChoiceField(label='Hotelzimmer benötigt:', choices=HOTEL_CHOICES.items(), widget=RadioSelect())

    class Media:
        js = ('dropdown/js/otrs_link.js',)
        css = {
             'all': ('css/dateFieldNoNowShortcutInTravels.css',)
        }


class LibraryForm(BaseApplicationForm, CommonOrderMixin):

    class Meta:
        model = Library
        fields = ['cost', 'library', 'duration', 'notes', 'survey_mail_send']
        exclude = ['intern_notes', 'survey_mail_send', 'mail_state']

    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)

        self.fields['library'].label = self._meta.model.LIBRARY_LABEL
        self.fields['library'].help_text = self._meta.model.LIBRARY_HELP_TEXT
        self.fields['duration'].help_text = self._meta.model.DURATION_HELP_TEXT


class ELiteratureForm(LibraryForm):

    class Meta(LibraryForm.Meta):
        model = ELiterature


class SoftwareForm(LibraryForm):

    class Meta(LibraryForm.Meta):
        model = Software


class HonoraryCertificateForm(FdbForm):

    class Meta:
        model = HonoraryCertificate
        fields = ['request_url', 'project']
        exclude = ['intern_notes']
    class Media:
        js = ('dropdown/js/otrs_link.js',)


class IFGForm(BaseApplicationForm, CommonOrderMixin):
    class Meta:
        model = IFG
        fields = ['cost', 'url', 'notes']
        exclude = ['intern_notes', 'survey_mail_send', 'mail_state']


class CheckForm(FdbForm):
    termstoaccept = settings.NUTZUNGSBEDINGUNGEN

    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.fields['check'] = BooleanField(
            required=True,
            label=format_html(
                "Ich stimme den <a href='{}'>Nutzungsbedingungen</a> zu",
                self.termstoaccept
            )
        )



    """Baseclass for all classes which need a check for Nutzungsbedingungen"""
#    def __init__(self, *args, **kwargs):
#    check = BooleanField(required=True,
#                        label=format_html("Ich stimme den <a href='{}'>Nutzungsbedingungen</a> zu",
#                        termstoaccept))
#                         NUTZUNGSBEDINGUNGEN))


class LiteratureForm(BaseApplicationForm, CommonOrderMixin):
    termstoaccept = settings.NUTZUNGSBEDINGUNGEN_LITERATURSTIPENDIUM

    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.fields['selfbuy_give_data'].required = True
    class Meta:
        model = Literature
        fields = ['cost', 'info', 'source', 'notes', 'selfbuy', 'selfbuy_data', 'selfbuy_give_data']
        exclude = ['intern_notes', 'survey_mail_send', 'mail_state']
    class Media:
        js = ('dropdown/js/literature.js',)

ADULT_CHOICES = {'TRUE': mark_safe('Ich bin volljährig.'),
           'FALSE': mark_safe('Ich bin noch nicht volljährig.')
        }


class EmailForm(BaseApplicationForm, CommonOrderMixin):

    termstoaccept = settings.NUTZUNGSBEDINGUNGEN_EMAIL_SERVICE

    # this is the code, to change required to false if needed
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.fields['adult'].required = True
        self.fields['other'].required = True

    adult = ChoiceField(label='Volljährigkeit', choices=ADULT_CHOICES.items(), widget=RadioSelect())



    # TODO: add some javascript to show/hide other-field
    class Meta:
        model = Email
        fields = ['domain', 'address', 'other', 'adult']
        exclude = ['intern_notes', 'survey_mail_send', 'mail_state']
    class Media:
        js = ('dropdown/js/mail.js',)



class BusinessCardForm(BaseApplicationForm, CommonOrderMixin):
    termstoaccept = settings.NUTZUNGSBEDINGUNGEN_VISITENKARTEN
    # this is the code, to change required to false if needed
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.fields['url_of_pic'].required = True
        self.fields['send_data_to_print'].required = True

    class Meta:
        model = BusinessCard
        exclude = ['intern_notes', 'survey_mail_send', 'mail_state']
        fields = ['project', 'data', 'variant', 'url_of_pic', 'send_data_to_print', 'sent_to']
    class Media:
        js = ('dropdown/js/businessCard.js',)


class ListForm(BaseApplicationForm, CommonOrderMixin):
    termstoaccept = settings.NUTZUNGSBEDINGUNGEN_MAILINGLISTEN
    class Meta:
        model = List
        fields = ['domain', 'address']
        exclude = ['intern_notes', 'survey_mail_send','mail_state']