Invoices: Support font choice and Arabic text (#3343)

Co-authored-by: Richard Schreiber <schreiber@rami.io>

src/pretix/base/settings.py

@@ -96,6 +96,18 @@ def primary_font_kwargs():
     }
 
 
+def invoice_font_kwargs():
+    from pretix.presale.style import get_fonts
+
+    choices = [('Open Sans', 'Open Sans')]
+    choices += sorted([
+        (a, a) for a, v in get_fonts().items()
+    ], key=lambda a: a[0])
+    return {
+        'choices': choices,
+    }
+
+
 def restricted_plugin_kwargs():
     from pretix.base.plugins import get_all_plugins
 
@@ -644,6 +656,19 @@ DEFAULTS = {
             help_text=_("Only respected by some invoice renderers."),
         )
     },
+    'invoice_renderer_font': {
+        'default': 'Open Sans',
+        'type': str,
+        'form_class': forms.ChoiceField,
+        'serializer_class': serializers.ChoiceField,
+        'serializer_kwargs': lambda: dict(**invoice_font_kwargs()),
+        'form_kwargs': lambda: dict(
+            label=_('Font'),
+            help_text=_("Only respected by some invoice renderers."),
+            required=True,
+            **invoice_font_kwargs()
+        ),
+    },
     'invoice_renderer': {
         'default': 'classic',  # default for new events is 'modern1'
         'type': str,