Introduce TimespanMixins

apis_core/apis_metainfo/mixins/dt.py

@@ -0,0 +1,49 @@
+# SPDX-FileCopyrightText: 2023 Birger Schacht
+# SPDX-License-Identifier: MIT
+
+"""
+Date and Time related Mixins
+"""
+
+from django.db.models import DateTimeField, CharField
+from django.core.exceptions import ValidationError
+from django.utils.translation import gettext as _
+
+from apis_core.helper_functions import DateParser
+
+
+class TimespanMixin:
+    """A simple mixin to implement a timespan"""
+
+    begin = DateTimeField(blank=True, null=True)
+    end = DateTimeField(blank=True, null=True)
+
+
+class TimespanInvervalMixin(TimespanMixin):
+    """A timespan mixin of which the begin and the end consist of invervals"""
+
+    begin_from = DateTimeField(blank=True, null=True)
+    begin_to = DateTimeField(blank=True, null=True)
+    end_from = DateTimeField(blank=True, null=True)
+    end_to = DateTimeField(blank=True, null=True)
+
+    def clean(self):
+        if self.begin_from > self.begin_to:
+            raise ValidationError(_("Begin from can not be greater than begin to."))
+        if self.end_from > self.end_to:
+            raise ValidationError(_("End from can not be greater than end to."))
+
+
+class ParseTimespanIntervalMixin(TimespanMixin):
+    """A timespan inverval mixin that allows to enter the date in a string field"""
+
+    begin_string = CharField(
+        max_length=255, blank=True, null=True, verbose_name=_("Begin")
+    )
+    end_string = CharField(max_length=255, blank=True, null=True, verbose_name=_("End"))
+
+    def save(self, *args, **kwargs):
+        if self.begin_string:
+            self.begin, self.begin_from, self.begin_to = DateParser(self.begin_string)
+        if self.end_string:
+            self.end, self.end_from, self.end_to = DateParser(self.end_string)