Migrations + Cleanup

* adds needed migrations
* refactors forms.py (700+ lines) in main konova app
    * splits into forms/ and forms/modals and single class/topic-files for better maintainability and overview
* fixes bug in main konova app migration which could occur if a certain compensation migration did not run before

konova/forms/geometry_form.py

@@ -0,0 +1,133 @@
+"""
+Author: Michel Peltriaux
+Organization: Struktur- und Genehmigungsdirektion Nord, Rhineland-Palatinate, Germany
+Contact: ksp-servicestelle@sgdnord.rlp.de
+Created on: 15.08.22
+
+"""
+import json
+
+from django.contrib.gis import gdal
+from django.contrib.gis.forms import MultiPolygonField
+from django.contrib.gis.geos import MultiPolygon, Polygon
+from django.utils.translation import gettext_lazy as _
+
+from konova.forms.base_form import BaseForm
+from konova.models import Geometry
+from konova.tasks import celery_update_parcels
+from konova.sub_settings.lanis_settings import DEFAULT_SRID_RLP
+from user.models import UserActionLogEntry
+
+
+class SimpleGeomForm(BaseForm):
+    """ A geometry form for rendering geometry read-only using a widget
+
+    """
+    read_only = True
+    geom = MultiPolygonField(
+        srid=DEFAULT_SRID_RLP,
+        label=_("Geometry"),
+        help_text=_(""),
+        label_suffix="",
+        required=False,
+        disabled=False,
+    )
+
+    def __init__(self, *args, **kwargs):
+        self.read_only = kwargs.pop("read_only", True)
+        super().__init__(*args, **kwargs)
+
+        # Initialize geometry
+        try:
+            geom = self.instance.geometry.geom
+            self.empty = geom.empty
+
+            if self.empty:
+                raise AttributeError
+
+            geojson = self.instance.geometry.as_feature_collection(srid=DEFAULT_SRID_RLP)
+            geom = json.dumps(geojson)
+        except AttributeError:
+            # If no geometry exists for this form, we simply set the value to None and zoom to the maximum level
+            geom = ""
+            self.empty = True
+
+        self.initialize_form_field("geom", geom)
+
+    def is_valid(self):
+        super().is_valid()
+        is_valid = True
+
+        # Get geojson from form
+        geom = self.data["geom"]
+        if geom is None or len(geom) == 0:
+            # empty geometry is a valid geometry
+            return is_valid
+        geom = json.loads(geom)
+
+        # Write submitted data back into form field to make sure invalid geometry
+        # will be rendered again on failed submit
+        self.initialize_form_field("geom", self.data["geom"])
+
+        # Read geojson into gdal geometry
+        # HINT: This can be simplified if the geojson format holds data in epsg:4326 (GDAL provides direct creation for
+        # this case)
+        features = []
+        features_json = geom.get("features", [])
+        for feature in features_json:
+            g = gdal.OGRGeometry(json.dumps(feature.get("geometry", feature)), srs=DEFAULT_SRID_RLP)
+            if g.geom_type not in ["Polygon", "MultiPolygon"]:
+                self.add_error("geom", _("Only surfaces allowed. Points or lines must be buffered."))
+                is_valid = False
+                return is_valid
+
+            polygon = Polygon.from_ewkt(g.ewkt)
+            is_valid = polygon.valid
+            if not is_valid:
+                self.add_error("geom", polygon.valid_reason)
+                return is_valid
+
+            features.append(polygon)
+        form_geom = MultiPolygon(srid=DEFAULT_SRID_RLP)
+        for feature in features:
+            form_geom = form_geom.union(feature)
+
+        # Make sure to convert into a MultiPolygon. Relevant if a single Polygon is provided.
+        if form_geom.geom_type != "MultiPolygon":
+            form_geom = MultiPolygon(form_geom, srid=DEFAULT_SRID_RLP)
+
+        # Write unioned Multipolygon into cleaned data
+        if self.cleaned_data is None:
+            self.cleaned_data = {}
+        self.cleaned_data["geom"] = form_geom.ewkt
+
+        return is_valid
+
+    def save(self, action: UserActionLogEntry):
+        """ Saves the form's geometry
+
+        Creates a new geometry entry if none is set, yet
+
+        Args:
+            action ():
+
+        Returns:
+
+        """
+        try:
+            if self.instance is None or self.instance.geometry is None:
+                raise LookupError
+            geometry = self.instance.geometry
+            geometry.geom = self.cleaned_data.get("geom", MultiPolygon(srid=DEFAULT_SRID_RLP))
+            geometry.modified = action
+
+            geometry.save()
+        except LookupError:
+            # No geometry or linked instance holding a geometry exist --> create a new one!
+            geometry = Geometry.objects.create(
+                geom=self.cleaned_data.get("geom", MultiPolygon(srid=DEFAULT_SRID_RLP)),
+                created=action,
+            )
+        # Start the parcel update procedure in a background process
+        celery_update_parcels.delay(geometry.id)
+        return geometry