Restructuring bidirectionalTool to improve maintainability

Packages/ohif-lesiontracker/client/compatibility/bidirectionalTool/mouseMoveCallback.js

@@ -0,0 +1,64 @@
+import { cornerstone, cornerstoneTools } from 'meteor/ohif:cornerstone';
+import { toolType } from './definitions';
+import pointNearTool from './pointNearTool';
+
+// Replaces the cornerstoneTools.handleActivator function by skiping the active handle comparison
+const handleActivator = (element, handles, canvasPoint, distanceThreshold=6) => {
+    const nearbyHandle = cornerstoneTools.getHandleNearImagePoint(element, handles, canvasPoint, distanceThreshold);
+
+    let handleActivatorChanged = false;
+    Object.keys(handles).forEach(handleKey => {
+        if (handleKey === 'textBox') return;
+        const handle = handles[handleKey];
+        const newActiveState = handle === nearbyHandle;
+        if (handle.active !== newActiveState) {
+            handleActivatorChanged = true;
+        }
+
+        handle.active = newActiveState;
+    });
+
+    return handleActivatorChanged;
+};
+
+// mouseMoveCallback is used to hide handles when mouse is away
+export default function (event, eventData) {
+    cornerstoneTools.toolCoordinates.setCoords(eventData);
+    // if a mouse button is down, do nothing
+    if (eventData.which !== 0) {
+        return;
+    }
+
+    // if we have no tool data for this element, do nothing
+    const toolData = cornerstoneTools.getToolState(eventData.element, toolType);
+    if (!toolData) return;
+
+    // We have tool data, search through all data and see if we can activate a handle
+    let imageNeedsUpdate = false;
+    for (let i = 0; i < toolData.data.length; i++) {
+        // get the cursor position in canvas coordinates
+        const coords = eventData.currentPoints.canvas;
+
+        const data = toolData.data[i];
+        const handleActivatorChanged = handleActivator(eventData.element, data.handles, coords);
+        Object.keys(data.handles).forEach(handleKey => {
+            if (handleKey === 'textBox') return;
+            const handle = data.handles[handleKey];
+            handle.hover = handle.active;
+        });
+
+        if (handleActivatorChanged) {
+            imageNeedsUpdate = true;
+        }
+
+        if ((pointNearTool(eventData.element, data, coords) && !data.active) || (!pointNearTool(eventData.element, data, coords) && data.active)) {
+            data.active = !data.active;
+            imageNeedsUpdate = true;
+        }
+    }
+
+    // Handle activation status changed, redraw the image
+    if (imageNeedsUpdate === true) {
+        cornerstone.updateImage(eventData.element);
+    }
+}