Initial draft

Author: mrbazzan

djangocms_picture/fields.py

@@ -0,0 +1,79 @@
+from django.contrib.contenttypes.fields import GenericForeignKey
+from django.contrib.contenttypes.models import ContentType
+from django import forms
+from django.db import models
+
+
+class PictureWidget(forms.MultiWidget):
+    def __init__(self):
+        widgets = [
+            forms.Select(attrs={},choices=[
+                (ct.id, ct.name) for ct in ContentType.objects.filter(id=45)
+            ]),
+            forms.NumberInput(attrs={}),
+        ]
+        super().__init__(widgets)
+
+    def decompress(self, value):
+        print("Decompress Value: ", value)
+        if value:
+            return [value.content_type.id, value.object_id]
+        return [None, None]
+
+    def value_from_datadict(self, data, file, name):
+        value = super().value_from_datadict(data, file, name)
+        value = ContentType.objects.filter(id=value[0]).first()
+        return value
+
+
+class PictureFormField(forms.Field):
+    widget = PictureWidget
+
+    def __init__(self, *args, **kwargs):
+        kwargs.pop('encoder', None)
+        kwargs.pop('decoder', None)
+        super().__init__(*args, **kwargs)
+
+    def prepare_value(self, value):
+        print("picture form: ", value)
+        # if we return list or tuple from here,
+        # django skips decompress
+        # value = (4, 3)
+        return value
+
+    # def to_python(self, value):
+    #     # This is called inside `clean`
+    #     # Note that `clean` is called inside `full_clean`'s `_clean_fields()`
+    #     pass
+
+
+class PictureField(GenericForeignKey, models.JSONField):
+    def __init__(self, **kwargs):
+        # call to models.JSONField
+        super(GenericForeignKey, self).__init__(**kwargs)
+
+        # call to GenericForeignKey
+        super().__init__(**kwargs)
+        self.editable = True
+
+    def contribute_to_class(self, cls, name):
+        ct = models.ForeignKey(ContentType,
+                               editable=False,
+                               on_delete=models.CASCADE)
+        fk = models.PositiveIntegerField(editable=False)
+
+        self.ct_field = picture_ct = f"{name}_ct"
+        self.fk_field = picture_fk = f"{name}_fk"
+ 
+        cls.add_to_class(picture_ct, ct)
+        cls.add_to_class(picture_fk, fk)
+        super().contribute_to_class(cls, name)
+
+        # this is required by _post_clean hook used during
+        # model validation in forms
+        self.attname = self.name
+
+    def formfield(self, **kwargs):
+        kwargs.setdefault("form_class", PictureFormField)
+        return super().formfield(**kwargs)
+