#138 WIP First draft

* adds first working draft of netgis map client

konova/forms.py

@@ -5,18 +5,20 @@ Contact: michel.peltriaux@sgdnord.rlp.de
 Created on: 16.11.20
 
 """
-
+import json
 from abc import abstractmethod
 
 from bootstrap_modal_forms.forms import BSModalForm
 from bootstrap_modal_forms.utils import is_ajax
 from django import forms
 from django.contrib import messages
+from django.contrib.gis import gdal
 from django.db.models.fields.files import FieldFile
 
+from konova.sub_settings.lanis_settings import DEFAULT_SRID_RLP
 from user.models import User
 from django.contrib.gis.forms import OSMWidget, MultiPolygonField
-from django.contrib.gis.geos import MultiPolygon
+from django.contrib.gis.geos import MultiPolygon, GEOSGeometry, Polygon
 from django.db import transaction
 from django.http import HttpRequest, HttpResponseRedirect
 from django.shortcuts import render
@@ -274,7 +276,7 @@ class SimpleGeomForm(BaseForm):
     """
     read_only = True
     geom = MultiPolygonField(
-        srid=DEFAULT_SRID,
+        srid=DEFAULT_SRID_RLP,
         label=_("Geometry"),
         help_text=_(""),
         label_suffix="",
@@ -289,15 +291,47 @@ class SimpleGeomForm(BaseForm):
         # Initialize geometry
         try:
             geom = self.instance.geometry.geom
+            geom.transform(ct=DEFAULT_SRID_RLP)
             self.empty = geom.empty
+            geom = geom.geojson
         except AttributeError:
             # If no geometry exists for this form, we simply set the value to None and zoom to the maximum level
-            geom = None
+            geom = ""
             self.empty = True
             self.fields["geom"].widget.attrs["default_zoom"] = 1
 
         self.initialize_form_field("geom", geom)
 
+    def is_valid(self):
+        super_valid = super().is_valid()
+        is_valid = True
+
+        # Get geojson from form
+        geom = self.data["geom"]
+        geom = json.loads(geom)
+
+        # Read geojson into gdal geometry
+        features = []
+        features_json = geom["features"]
+        for feature in features_json:
+            g = gdal.OGRGeometry(json.dumps(feature["geometry"]), 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
+            features.append(g)
+        if len(features) > 0:
+            form_geom = features[0]
+            for g in features[1:]:
+                form_geom = form_geom.union(g)
+            form_geom.transform(coord_trans=DEFAULT_SRID)
+            if form_geom.geom_type != "MultiPolygon":
+                form_geom = MultiPolygon(MultiPolygon.from_ewkt(form_geom.ewkt))
+            self.cleaned_data = {
+                "geom": form_geom.wkt
+            }
+        return is_valid
+
     def save(self, action: UserActionLogEntry):
         """ Saves the form's geometry