Allow customers to change to a different product variation (#1719)

2020-07-20 16:36:24 +02:00
parent c8ef825de5
commit e7b9c49620
17 changed files with 952 additions and 132 deletions
--- a/src/pretix/presale/forms/order.py
+++ b/src/pretix/presale/forms/order.py
@@ -0,0 +1,96 @@
+from decimal import Decimal
+
+from django import forms
+from django.utils.translation import ugettext_lazy as _
+
+from pretix.base.models import Quota
+from pretix.base.models.tax import TaxedPrice
+from pretix.base.services.pricing import get_price
+from pretix.base.services.quotas import QuotaAvailability
+from pretix.base.templatetags.money import money_filter
+
+
+class OrderPositionChangeForm(forms.Form):
+    itemvar = forms.ChoiceField(
+        label=_('Product'),
+        required=False,
+    )
+
+    def __init__(self, *args, **kwargs):
+        instance = kwargs.pop('instance')
+        invoice_address = kwargs.pop('invoice_address')
+        initial = kwargs.get('initial', {})
+        event = kwargs.pop('event')
+        kwargs['initial'] = initial
+        if instance.variation_id:
+            initial['itemvar'] = f'{instance.item_id}-{instance.variation_id}'
+        else:
+            initial['itemvar'] = f'{instance.item_id}'
+
+        super().__init__(*args, **kwargs)
+
+        choices = []
+
+        i = instance.item
+        pname = str(i)
+        variations = list(i.variations.all())
+
+        if variations:
+            current_quotas = instance.variation.quotas.all() if instance.variation else instance.item.quotas.all()
+            qa = QuotaAvailability()
+            for v in variations:
+                qa.queue(*v.quotas.all())
+            qa.compute()
+
+            for v in variations:
+
+                label = f'{i.name} – {v.value}'
+                if instance.variation_id == v.id:
+                    choices.append((f'{i.pk}-{v.pk}', label))
+                    continue
+
+                if not v.active:
+                    continue
+
+                q_res = [qa.results[q][0] != Quota.AVAILABILITY_OK for q in v.quotas.all() if q not in current_quotas]
+                if not v.quotas.all() or (q_res and any(q_res)):
+                    continue
+
+                new_price = get_price(i, v, voucher=instance.voucher, subevent=instance.subevent,
+                                      invoice_address=invoice_address)
+                current_price = TaxedPrice(tax=instance.tax_value, gross=instance.price, net=instance.price - instance.tax_value,
+                                           name=instance.tax_rule.name if instance.tax_rule else '', rate=instance.tax_rate)
+                if new_price.gross < current_price.gross and event.settings.change_allow_user_price == 'gt':
+                    continue
+                if new_price.gross != current_price.gross and event.settings.change_allow_user_price == 'eq':
+                    continue
+
+                if new_price.gross < current_price.gross:
+                    if event.settings.display_net_prices:
+                        label += ' (- {} {})'.format(money_filter(current_price.gross - new_price.gross, event.currency), _('plus taxes'))
+                    else:
+                        label += ' (- {})'.format(money_filter(current_price.gross - new_price.gross, event.currency))
+                elif current_price.gross < new_price.gross:
+                    if event.settings.display_net_prices:
+                        label += ' ({}{} {})'.format(
+                            '+ ' if current_price.gross != Decimal('0.00') else '',
+                            money_filter(new_price.gross - current_price.gross, event.currency),
+                            _('plus taxes')
+                        )
+                    else:
+                        label += ' ({}{})'.format(
+                            '+ ' if current_price.gross != Decimal('0.00') else '',
+                            money_filter(new_price.gross - current_price.gross, event.currency)
+                        )
+
+                choices.append((f'{i.pk}-{v.pk}', label))
+
+            if not choices:
+                self.fields['itemvar'].widget.attrs['disabled'] = True
+                self.fields['itemvar'].help_text = _('No other variation of this product is currently available for you.')
+        else:
+            choices.append((str(i.pk), '%s' % pname))
+            self.fields['itemvar'].widget.attrs['disabled'] = True
+            self.fields['itemvar'].help_text = _('No other variations of this product exist.')
+
+        self.fields['itemvar'].choices = choices