From 0492a7a466d510c2809bbb47f4756b3f9c7eb3d3 Mon Sep 17 00:00:00 2001
From: huyenngn <ngan-huyen.thi-nguyen@deutschebahn.com>
Date: Mon, 2 Sep 2024 19:30:03 +0200
Subject: [PATCH] fix: Fix snapping of oblique edges

---
 capellambse/aird/_edge_factories.py | 24 +++++++++++++++++++++---
 capellambse/diagram/_diagram.py     |  5 ++++-
 capellambse/svg/drawing.py          |  2 ++
 3 files changed, 27 insertions(+), 4 deletions(-)

diff --git a/capellambse/aird/_edge_factories.py b/capellambse/aird/_edge_factories.py
index 1ce5b6ff..624c5596 100644
--- a/capellambse/aird/_edge_factories.py
+++ b/capellambse/aird/_edge_factories.py
@@ -62,13 +62,14 @@ def generic_factory(seb: C.SemanticElementBuilder) -> diagram.Edge:
     edge.styleoverrides = _styling.apply_style_overrides(
         seb.target_diagram.styleclass, f"Edge.{seb.styleclass}", ostyle
     )  # type: ignore[assignment]
-    edge.labels.extend(_construct_labels(edge, seb))
 
     if isinstance(targetport, diagram.Box):
         snaptarget(edge, -1, -2, targetport, not edge.hidden, routingstyle)
     if isinstance(sourceport, diagram.Box):
         snaptarget(edge, 0, 1, sourceport, not edge.hidden, routingstyle)
 
+    edge.labels.extend(_construct_labels(edge, seb))
+
     sourceport.add_context(seb.data_element.attrib["element"])
     if targetport is not None:
         targetport.add_context(seb.data_element.attrib["element"])
@@ -310,9 +311,18 @@ def snap_oblique(
     target: diagram.DiagramElement,
 ) -> None:
     """Snap ``points``' end to ``target`` in a straight line."""
-    points[i] = target.vector_snap(
-        points[i], source=points[next_i], style=diagram.RoutingStyle.OBLIQUE
+    source = points[next_i]
+    new_point = target.vector_snap(
+        points[i], style=diagram.RoutingStyle.OBLIQUE, source=source
     )
+    delta = (points[i] - source).angleto(new_point - source)
+    if (math.ceil(delta) != 0) and (math.floor(delta) != 0):
+        new_point = target.vector_snap(
+            source,
+            style=diagram.RoutingStyle.OBLIQUE,
+            source=points[next_i - i + next_i],
+        )
+    points[i] = new_point
 
 
 def snap_manhattan(
@@ -388,6 +398,14 @@ def _construct_labels(
             int(layout.attrib.get("height", "0")),
         )
 
+        if melodyobj.tag == "ownedFeatures" and len(melodyobj) == 2:
+            start_obj, end_obj = melodyobj
+            start, end = start_obj.get("value", "1"), end_obj.get("value", "1")
+            if (start != "1") or (end != "1"):
+                if start_obj.tag != "ownedMinCard":
+                    end, start = start, end
+                labeltext = f"[{start}..{end}] {labeltext}"
+
         # Rotate the position vector into place
         label_pos = label_pos.rotatedby(travel_direction.angleto((1, 0)))
 
diff --git a/capellambse/diagram/_diagram.py b/capellambse/diagram/_diagram.py
index c0f38307..8f516068 100644
--- a/capellambse/diagram/_diagram.py
+++ b/capellambse/diagram/_diagram.py
@@ -272,7 +272,7 @@ def vector_snap(
             source = diagram.Vector2D(*source)
 
         if style is RoutingStyle.OBLIQUE:
-            return self.__vector_snap_oblique(source)
+            return self.__vector_snap_oblique(point)
         if style is RoutingStyle.MANHATTAN:
             return self.__vector_snap_manhattan(point, point - source)
         if style is RoutingStyle.TREE:
@@ -282,6 +282,9 @@ def vector_snap(
     def __vector_snap_oblique(
         self, source: diagram.Vector2D
     ) -> diagram.Vector2D:
+        if source == self.center:
+            return source
+
         angle = self.size.angleto(source - self.center)
         alpha = 2 * self.size.angleto((1, 0))
         assert alpha >= 0
diff --git a/capellambse/svg/drawing.py b/capellambse/svg/drawing.py
index dedbf285..0a903d6a 100644
--- a/capellambse/svg/drawing.py
+++ b/capellambse/svg/drawing.py
@@ -286,6 +286,8 @@ def _draw_feature_text(
 
     def _draw_label(self, builder: LabelBuilder) -> LinesData | None:
         """Draw label text on given object and return the label's group."""
+        if not builder.labels:
+            return None
         builder.icon &= diagram.has_icon(builder.class_ or "")
         text = self._make_text(builder)
         lines = None