fix #5219 underlay links are now base64 encoded in the svg before sending it to web UI

this is not really the best solution and might need to look for better ones

src/bonsai/bonsai/bim/data/webui/sioserver.py

@@ -1,6 +1,6 @@
 import sys
 import os
-import webbrowser
+
 
 bonsai_lib_path = os.environ.get("BONSAI_LIB_PATH")
 bonsai_version = os.environ.get("BONSAI_VERSION")
@@ -13,6 +13,8 @@ from aiohttp import web
 import socketio
 import pystache
 import json
+import base64
+import xml.etree.ElementTree as ET
 
 sio_port = 8080  # default port
 
@@ -56,9 +58,8 @@ class WebNamespace(socketio.AsyncNamespace):
 
     async def on_get_svg(self, sid, data):
         file_path = data["path"]
-        with open(file_path, "r") as file:
-            svg_data = file.read()
-        await sio.emit("svg_data", svg_data, room=sid, namespace="/web")
+        svg = await self.process_svg(file_path)
+        await sio.emit("svg_data", svg, room=sid, namespace="/web")
 
     async def send_cached_messages(self, sid):
         # Send cached messages to the connected web client
@@ -70,6 +71,35 @@ class WebNamespace(socketio.AsyncNamespace):
             if "demo_data" in messages:
                 await self.emit("demo_data", {"blenderId": blenderId, "data": messages["demo_data"]}, room=sid)
 
+    async def process_svg(self, file_path):
+        def encode_image(filepath):
+            # Encode file content to base64 string
+            with open(filepath, "rb") as file:
+                encoded_string = base64.b64encode(file.read()).decode("utf-8")
+            return f"data:image;base64,{encoded_string}"
+
+        file_dir = os.path.dirname(file_path)
+
+        ET.register_namespace("", "http://www.w3.org/2000/svg")
+        ET.register_namespace("xlink", "http://www.w3.org/1999/xlink")
+
+        tree = ET.parse(file_path)
+        root = tree.getroot()
+
+        namespaces = {
+            "svg": "http://www.w3.org/2000/svg",
+            "xlink": "http://www.w3.org/1999/xlink",
+        }
+
+        for element in root.findall(".//svg:image[@xlink:href]", namespaces):
+            href = element.get("{http://www.w3.org/1999/xlink}href")
+            if href and href.endswith((".png", ".svg", ".jpeg")):
+                img_path = os.path.join(file_dir, href)
+                if os.path.exists(img_path):
+                    base64_data = encode_image(img_path)
+                    element.set("{http://www.w3.org/1999/xlink}href", base64_data)
+        return ET.tostring(root, "unicode")
+
 
 # Blender namespace
 class BlenderNamespace(socketio.AsyncNamespace):