Fix #349 -- Allow to clone an event

src/pretix/control/forms/event.py

@@ -26,22 +26,13 @@ class EventWizardFoundationForm(forms.Form):
         self.fields['organizer'] = forms.ModelChoiceField(
             label=_("Organizer"),
             queryset=Organizer.objects.filter(
-                id__in=self.user.organizer_perms.filter(can_create_events=True).values_list('id', flat=True)
+                id__in=self.user.organizer_perms.filter(can_create_events=True).values_list('organizer', flat=True)
             ),
             widget=forms.RadioSelect,
             empty_label=None,
             required=True
         )
 
-    def clean_slug(self):
-        slug = self.cleaned_data['slug']
-        if Event.objects.filter(slug=slug, organizer=self.organizer).exists():
-            raise forms.ValidationError(
-                self.error_messages['duplicate_slug'],
-                code='duplicate_slug'
-            )
-        return slug
-
 
 class EventWizardBasicsForm(I18nModelForm):
     error_messages = {
@@ -100,6 +91,26 @@ class EventWizardBasicsForm(I18nModelForm):
         return slug
 
 
+class EventWizardCopyForm(forms.Form):
+
+    def __init__(self, *args, **kwargs):
+        kwargs.pop('organizer')
+        kwargs.pop('locales')
+        self.user = kwargs.pop('user')
+        super().__init__(*args, **kwargs)
+        self.fields['copy_from_event'] = forms.ModelChoiceField(
+            label=_("Copy configuration from"),
+            queryset=Event.objects.filter(
+                id__in=self.user.event_perms.filter(
+                    can_change_items=True, can_change_settings=True
+                ).values_list('event', flat=True)
+            ),
+            widget=forms.RadioSelect,
+            empty_label=_('Do not copy'),
+            required=True
+        )
+
+
 class EventUpdateForm(I18nModelForm):
     def clean_slug(self):
         return self.instance.slug

src/pretix/control/templates/pretixcontrol/events/create_copy.html

@@ -0,0 +1,20 @@
+{% extends "pretixcontrol/events/create_base.html" %}
+{% load i18n %}
+{% load bootstrap3 %}
+{% block form %}
+    <p>
+        {% blocktrans trimmed %}
+            Do you want to copy over your configuration from a different event? We will copy all
+			products, categories, quotas, and questions as well as general event settings.
+        {% endblocktrans %}
+    </p>
+    <div class="alert alert-info">
+        <strong>
+            {% blocktrans trimmed %}
+                Please make sure to review all settings extensively. You will probably still need to change some
+                settings manually, e.g. date and time settings and texts that contain the event name.
+            {% endblocktrans %}
+        </strong>
+    </div>
+    {% bootstrap_field form.copy_from_event layout="horizontal" %}
+{% endblock %}

src/pretix/control/views/main.py

@@ -9,7 +9,7 @@ from formtools.wizard.views import SessionWizardView
 
 from pretix.base.models import Event, EventPermission
 from pretix.control.forms.event import (
-    EventWizardBasicsForm, EventWizardFoundationForm,
+    EventWizardBasicsForm, EventWizardCopyForm, EventWizardFoundationForm,
 )
 
 
@@ -27,17 +27,25 @@ class EventList(ListView):
         )
 
 
+def condition_copy(wizard):
+    return EventPermission.objects.filter(
+        user=wizard.request.user, can_change_settings=True, can_change_items=True
+    ).exists()
+
+
 class EventWizard(SessionWizardView):
     form_list = [
         ('foundation', EventWizardFoundationForm),
         ('basics', EventWizardBasicsForm),
+        ('copy', EventWizardCopyForm),
     ]
     templates = {
         'foundation': 'pretixcontrol/events/create_foundation.html',
-        'basics': 'pretixcontrol/events/create_basics.html'
+        'basics': 'pretixcontrol/events/create_basics.html',
+        'copy': 'pretixcontrol/events/create_copy.html',
     }
     condition_dict = {
-
+        'copy': condition_copy
     }
 
     def get_form_kwargs(self, step=None):
@@ -55,6 +63,7 @@ class EventWizard(SessionWizardView):
     def done(self, form_list, form_dict, **kwargs):
         foundation_data = self.get_cleaned_data_for_step('foundation')
         basics_data = self.get_cleaned_data_for_step('basics')
+        copy_data = self.get_cleaned_data_for_step('copy')
 
         with transaction.atomic():
             event = form_dict['basics'].instance
@@ -63,10 +72,6 @@ class EventWizard(SessionWizardView):
             form_dict['basics'].save()
             EventPermission.objects.create(event=event, user=self.request.user)
 
-            event.settings.set('timezone', basics_data['timezone'])
-            event.settings.set('locale', basics_data['locale'])
-            event.settings.set('locales', foundation_data['locales'])
-
             logdata = {}
             for f in form_list:
                 logdata.update({
@@ -74,7 +79,16 @@ class EventWizard(SessionWizardView):
                 })
             event.log_action('pretix.event.settings', user=self.request.user, data=logdata)
 
-        messages.success(self.request, _('The new event has been created.'))
+            if copy_data and copy_data['copy_from_event']:
+                from_event = copy_data['copy_from_event']
+                event.copy_data_from(from_event)
+
+            event.settings.set('timezone', basics_data['timezone'])
+            event.settings.set('locale', basics_data['locale'])
+            event.settings.set('locales', foundation_data['locales'])
+
+        messages.success(self.request, _('The new event has been created. You can now adjust the event settings in '
+                                         'detail.'))
         return redirect(reverse('control:event.settings', kwargs={
             'organizer': event.organizer.slug,
             'event': event.slug,