From d9c5bf1bd4e7cf9de248881672d820941ca34126 Mon Sep 17 00:00:00 2001
From: tegwick <bernd.worsch@gmail.com>
Date: Tue, 19 May 2026 00:16:57 +0200
Subject: [PATCH] Add graph selection anchors

---
 railiance_fabric/graph_explorer_ui.py | 134 +++++++++++++++++++++++++-
 tests/test_graph_explorer.py          |   3 +
 2 files changed, 136 insertions(+), 1 deletion(-)

diff --git a/railiance_fabric/graph_explorer_ui.py b/railiance_fabric/graph_explorer_ui.py
index 2278120..f9bd25f 100644
--- a/railiance_fabric/graph_explorer_ui.py
+++ b/railiance_fabric/graph_explorer_ui.py
@@ -129,6 +129,55 @@ def graph_explorer_page() -> str:
       box-shadow: 0 12px 30px rgba(23, 32, 51, .12);
     }
     .map-controls button { min-width: 54px; }
+    .selection-anchor {
+      position: absolute;
+      z-index: 5;
+      display: none;
+      width: 0;
+      height: 0;
+      pointer-events: none;
+      transform: translate(-50%, -100%);
+    }
+    .selection-anchor::before {
+      content: "";
+      position: absolute;
+      left: -1px;
+      top: -36px;
+      width: 2px;
+      height: 28px;
+      border-radius: 999px;
+      background: #111827;
+      box-shadow: 0 1px 2px rgba(23, 32, 51, .28);
+    }
+    .selection-anchor::after {
+      content: "";
+      position: absolute;
+      left: -6px;
+      top: -10px;
+      width: 0;
+      height: 0;
+      border-left: 6px solid transparent;
+      border-right: 6px solid transparent;
+      border-top: 10px solid #111827;
+      filter: drop-shadow(0 1px 1px rgba(23, 32, 51, .24));
+    }
+    .selection-anchor-label {
+      position: absolute;
+      left: 12px;
+      top: -48px;
+      max-width: 220px;
+      overflow: hidden;
+      border: 1px solid var(--line);
+      border-radius: 8px;
+      background: rgba(255, 255, 255, .96);
+      box-shadow: 0 12px 30px rgba(23, 32, 51, .12);
+      color: var(--text);
+      font-size: 12px;
+      line-height: 1.25;
+      padding: 6px 8px;
+      text-overflow: ellipsis;
+      white-space: nowrap;
+    }
     .button-row { display: flex; flex-wrap: wrap; gap: 8px; }
     .meta { color: var(--muted); font-size: 12px; margin: 0; }
     .pill {
@@ -203,6 +252,9 @@ def graph_explorer_page() -> str:
           <button type="button" data-action="focus" title="Focus selected neighborhood">Focus</button>
           <button type="button" data-action="clear" class="primary" title="Reset map controls">Reset</button>
         </div>
+        <div id="selection-anchor" class="selection-anchor" aria-hidden="true">
+          <span id="selection-anchor-label" class="selection-anchor-label"></span>
+        </div>
         <div id="popup" class="popup"></div>
       </div>
       <aside class="side">
@@ -248,6 +300,8 @@ def graph_explorer_page() -> str:
       const graphUrl = "/exports/graph-explorer";
       const canvas = document.getElementById("graph-canvas");
       const popup = document.getElementById("popup");
+      const selectionAnchor = document.getElementById("selection-anchor");
+      const selectionAnchorLabel = document.getElementById("selection-anchor-label");
       const searchInput = document.getElementById("search");
       const modeSelect = document.getElementById("mode-select");
       const layoutSelect = document.getElementById("layout-select");
@@ -272,6 +326,7 @@ def graph_explorer_page() -> str:
       const profileStorageKey = "railiance.fabric.graphExplorer.profiles";
       let cy = null;
       let selected = null;
+      let selectedAnchor = null;
       let focusSet = null;
       let manualOverrides = {};
       let layerColors = {};
@@ -354,6 +409,59 @@ def graph_explorer_page() -> str:
         }).join("");
       };
 
+      const isFinitePoint = (position) =>
+        position && Number.isFinite(position.x) && Number.isFinite(position.y);
+
+      const elementLabel = (element) => {
+        if (!element) return "";
+        const data = element.data();
+        return data.name || data.label || data.edgeType || data.id;
+      };
+
+      const renderedElementPosition = (element) => {
+        if (!element || !cy) return null;
+        if (element.isNode && element.isNode()) return element.renderedPosition();
+        if (element.isEdge && element.isEdge()) {
+          if (typeof element.renderedMidpoint === "function") {
+            const midpoint = element.renderedMidpoint();
+            if (isFinitePoint(midpoint)) return midpoint;
+          }
+          const source = cy.getElementById(element.data("source"));
+          const target = cy.getElementById(element.data("target"));
+          if (source.length > 0 && target.length > 0) {
+            const sourcePosition = source.renderedPosition();
+            const targetPosition = target.renderedPosition();
+            if (isFinitePoint(sourcePosition) && isFinitePoint(targetPosition)) {
+              return {
+                x: (sourcePosition.x + targetPosition.x) / 2,
+                y: (sourcePosition.y + targetPosition.y) / 2,
+              };
+            }
+          }
+        }
+        return null;
+      };
+
+      const updateSelectionAnchor = () => {
+        if (!selected || !selectionAnchor) {
+          selectedAnchor = null;
+          selectionAnchor.style.display = "none";
+          return;
+        }
+        const position = renderedElementPosition(selected);
+        if (isFinitePoint(position)) {
+          selectedAnchor = {x: position.x, y: position.y, label: elementLabel(selected)};
+        }
+        if (!selectedAnchor) {
+          selectionAnchor.style.display = "none";
+          return;
+        }
+        selectionAnchor.style.left = `${selectedAnchor.x}px`;
+        selectionAnchor.style.top = `${selectedAnchor.y}px`;
+        selectionAnchorLabel.textContent = selectedAnchor.label;
+        selectionAnchor.style.display = "block";
+      };
+
       const currentViewState = () => ({
         search: searchInput.value,
         mode: modeSelect.value || "full",
@@ -603,6 +711,7 @@ def graph_explorer_page() -> str:
         const hidden = cy.elements().length - visibleNodes - visibleEdges;
         counts.textContent = `${visibleNodes} nodes / ${visibleEdges} edges`;
         hiddenSummary.textContent = `Hidden ${hidden}`;
+        updateSelectionAnchor();
       };
 
       const showDetails = (element) => {
@@ -614,6 +723,7 @@ def graph_explorer_page() -> str:
           detailList.innerHTML = "";
           orientationTitle.textContent = "Select a service, interface, dependency, or registered-only repo.";
           orientationList.innerHTML = "";
+          updateSelectionAnchor();
           return;
         }
         const data = element.data();
@@ -639,6 +749,7 @@ def graph_explorer_page() -> str:
           .map(([key, value]) => `<li><strong>${escapeHtml(key)}</strong> ${escapeHtml(value)}</li>`)
           .join("");
         renderOrientation(element);
+        updateSelectionAnchor();
       };
 
       const renderOrientation = (element) => {
@@ -751,6 +862,7 @@ def graph_explorer_page() -> str:
               }
             : {name, padding: 48, animate: false};
         cy.layout(options).run();
+        updateSelectionAnchor();
       };
 
       const renderLegend = (layers) => {
@@ -809,6 +921,16 @@ def graph_explorer_page() -> str:
               "text-max-width": 130,
               "width": "data(visualSize)"
             }},
+            {selector: "node[layer = 'repository']", style: {"shape": "round-rectangle"}},
+            {selector: "node[layer = 'server']", style: {"shape": "pentagon"}},
+            {selector: "node[layer = 'deployment']", style: {"shape": "diamond"}},
+            {selector: "node[layer = 'service']", style: {"shape": "hexagon"}},
+            {selector: "node[layer = 'capability']", style: {"shape": "vee"}},
+            {selector: "node[layer = 'interface']", style: {"shape": "rectangle"}},
+            {selector: "node[layer = 'dependency']", style: {"shape": "triangle"}},
+            {selector: "node[layer = 'binding']", style: {"shape": "rhomboid"}},
+            {selector: "node[unresolved = true]", style: {"border-color": "#b45309", "border-style": "dashed", "border-width": 3}},
+            {selector: "node[lifecycle = 'registered-only']", style: {"border-color": "#be123c", "border-style": "dashed", "border-width": 3}},
             {selector: "edge", style: {
               "curve-style": "bezier",
               "line-color": "#98a2b3",
@@ -818,13 +940,23 @@ def graph_explorer_page() -> str:
             }},
             {selector: "edge[strength = 'strong']", style: {"line-color": "#344054", "target-arrow-color": "#344054"}},
             {selector: "edge[strength = 'weak']", style: {"line-style": "dotted"}},
+            {selector: "edge.hover", style: {
+              "label": "data(edgeType)",
+              "font-size": 10,
+              "text-background-color": "#ffffff",
+              "text-background-opacity": .9,
+              "text-background-padding": 2,
+              "z-index": 2
+            }},
             {selector: ".display-blur", style: {"opacity": .24, "label": ""}},
             {selector: ".display-blur:selected, .display-blur.hover", style: {"opacity": .78, "label": "data(label)"}},
-            {selector: ":selected", style: {"border-width": 4, "border-color": "#111827", "line-color": "#111827", "target-arrow-color": "#111827"}}
+            {selector: ":selected", style: {"overlay-opacity": 0}}
           ]
         });
         cy.on("tap", "node, edge", (event) => showDetails(event.target));
         cy.on("tap", (event) => { if (event.target === cy) showDetails(null); });
+        cy.on("pan zoom resize render layoutstop", updateSelectionAnchor);
+        cy.on("position", "node", updateSelectionAnchor);
         cy.on("mouseover", "node, edge", (event) => {
           event.target.addClass("hover");
           const data = event.target.data();
diff --git a/tests/test_graph_explorer.py b/tests/test_graph_explorer.py
index 632dfce..1177a39 100644
--- a/tests/test_graph_explorer.py
+++ b/tests/test_graph_explorer.py
@@ -208,9 +208,12 @@ def test_registry_serves_graph_explorer_exports(tmp_path: Path) -> None:
         assert 'id="layout-select"' in page
         assert 'id="node-type-filter"' in page
         assert 'id="edge-type-filter"' in page
+        assert 'id="selection-anchor"' in page
+        assert "updateSelectionAnchor" in page
         assert "Node Types" in page
         assert "Edge Types" in page
         assert 'id="layer-filter"' not in page
+        assert '"border-width": 4' not in page
         assert 'id="profile-select"' in page
         assert 'id="profile-name"' in page
         assert 'id="orientation-list"' in page