ISEPOS-2373 Also store the bounding box as a data attribute for quick access

src/seismic_hazard_forecasting.py

@@ -468,6 +468,16 @@ verbose: {verbose}")
         else:
             iml_grid_prep = iml_grid_raw
 
+        # TODO Remove. Saving coordinates to
+        # north, south = lat.max(), lat.min()
+        # east,  west  = lon.max(), lon.min()
+        # bbox_json = {"south": float(south), "west": float(west),
+        #              "north": float(north), "east": float(east)}
+        # with open("overlay_bounds.json", "w", encoding="utf‑8") as fh:
+        #     json.dump(bbox_json, fh, indent=2)
+        #
+        # logger.info(f"Saved bbox to overlay_bounds.json → {bbox_json}")
+
         for j in range(0, len(products)):
             vmin = min(x for x in iml_grid_prep[j] if x is not np.nan)
             vmax = max(x for x in iml_grid_prep[j] if x is not np.nan)
@@ -495,10 +505,48 @@ verbose: {verbose}")
 
             # Save the figure
             fig.canvas.draw()
-            plt.savefig("overlay_" + str(j) + ".svg", bbox_inches="tight", pad_inches=0, transparent=True)
+            svg_path = f"overlay_{j}.svg"
+            plt.savefig(svg_path, bbox_inches="tight", pad_inches=0, transparent=True)
             plt.close(fig)
 
+
+            import xml.etree.ElementTree as ET      # <-- TODO place this with other imports
+            import json
+
+            # -----------------------------------------
+            # Inject bounding box (BBOX) metadata into the SVG
+            # -----------------------------------------
+            north, south = lat.max(), lat.min()
+            east,  west  = lon.max(), lon.min()
+            bbox_dict = {
+                "south": float(south),
+                "west":  float(west),
+                "north": float(north),
+                "east":  float(east)
+            }
+            tree = ET.parse(svg_path)
+
+            root = tree.getroot()
+
+            # Remove any existing <metadata> tags
+            for old_meta in root.findall("{http://www.w3.org/2000/svg}metadata"):
+                root.remove(old_meta)
+
+            # Add new <metadata> element with the bounding box JSON
+            meta_elem = ET.SubElement(root, "metadata")
+            meta_elem.text = json.dumps(bbox_dict)
+
+            # (Optional) Also store the bounding box as a data attribute for quick access
+            root.set("data-bbox", json.dumps(bbox_dict))
+            tree.write(svg_path, encoding="utf-8", xml_declaration=True)
+            logger.info(f"Embedded bbox into {svg_path} → {bbox_dict}")
+
+            # -----------------------------------------
+            # END Inject bounding box (BBOX) metadata into the SVG
+            # -----------------------------------------
+
             # Make the color bar
+
             cmap_name = 'viridis'
             width = 50
             height = 500