Introduce zoom control with tentative UI

calm-visualizer/src/App.tsx

@@ -4,6 +4,7 @@ import Drawer from './components/drawer/Drawer';
 import Navbar from './components/navbar/Navbar';
 import { CALMArchitecture } from '../../shared/src/types';
 import React from 'react';
+import { ZoomProvider } from './components/zoom-context.provider';
 
 function App() {
     const [title, setTitle] = useState<string | undefined>(undefined);
@@ -21,20 +22,22 @@ function App() {
     }
 
     return (
-        <div className="h-screen flex flex-col">
-            <Navbar
-                handleUpload={handleFile}
-                isGraphRendered={instance ? true : false}
-                toggleNodeDesc={() => setNodeDescActive((isNodeDescActive) => !isNodeDescActive)}
-                toggleConnectionDesc={() => setConDescActive((isConDescActive) => !isConDescActive)}
-            />
-            <Drawer
-                isNodeDescActive={isNodeDescActive}
-                isConDescActive={isConDescActive}
-                calmInstance={instance}
-                title={title}
-            />
-        </div>
+        <ZoomProvider>
+            <div className="h-screen flex flex-col">
+                <Navbar
+                    handleUpload={handleFile}
+                    isGraphRendered={instance ? true : false}
+                    toggleNodeDesc={() => setNodeDescActive((isNodeDescActive) => !isNodeDescActive)}
+                    toggleConnectionDesc={() => setConDescActive((isConDescActive) => !isConDescActive)}
+                />
+                <Drawer
+                    isNodeDescActive={isNodeDescActive}
+                    isConDescActive={isConDescActive}
+                    calmInstance={instance}
+                    title={title}
+                />
+            </div>
+        </ZoomProvider>
     );
 }
 

calm-visualizer/src/components/cytoscape-renderer/CytoscapeRenderer.tsx

@@ -1,13 +1,14 @@
 /* eslint-disable @typescript-eslint/no-unused-vars */
 import './cytoscape.css';
-import { useEffect, useRef, useState } from 'react';
+import { useContext, useEffect, useRef, useState } from 'react';
 import cytoscape, { Core, EdgeSingular, NodeSingular } from 'cytoscape';
 import nodeHtmlLabel from 'cytoscape-node-html-label';
 import nodeEdgeHtmlLabel from 'cytoscape-node-edge-html-label';
 import coseBilkent from 'cytoscape-cose-bilkent';
 import expandCollapse from 'cytoscape-expand-collapse';
 import fcose from 'cytoscape-fcose';
 import Sidebar from '../sidebar/Sidebar';
+import { ZoomContext } from '../zoom-context.provider';
 
 //Make some information available on tooltip hover
 
@@ -50,7 +51,6 @@ export type Edge = {
     };
 };
 
-
 interface Props {
     title?: string;
     isNodeDescActive: boolean;
@@ -68,11 +68,16 @@ const CytoscapeRenderer = ({
 }: Props) => {
     const cyRef = useRef<HTMLDivElement>(null);
     const [cy, setCy] = useState<Core | null>(null);
+    const { zoomLevel, updateZoom } = useContext(ZoomContext);
     const [selectedNode, setSelectedNode] = useState<Node['data'] | null>(null);
     const [selectedEdge, setSelectedEdge] = useState<Edge['data'] | null>(null);
 
     useEffect(() => {
         if (cy) {
+            //Ensure cytoscape zoom and context state are synchronised
+            if (cy.zoom() !== zoomLevel) {
+                updateZoom(cy.zoom());
+            }
             /* eslint-disable @typescript-eslint/no-explicit-any */
             (cy as Core & { nodeHtmlLabel: any }).nodeHtmlLabel([
                 {
@@ -103,11 +108,13 @@ const CytoscapeRenderer = ({
                 setSelectedEdge(edge?.data()); // Update state with the clicked node's data
             });
 
+            cy.on('zoom', () => updateZoom(cy.zoom()));
+
             return () => {
                 cy.destroy();
             };
         }
-    }, [cy, isNodeDescActive]);
+    }, [cy, zoomLevel, updateZoom, isNodeDescActive]);
 
     useEffect(() => {
         // Initialize Cytoscape instance
@@ -154,6 +161,13 @@ const CytoscapeRenderer = ({
         );
     }, [nodes, edges, isConDescActive]); // Re-render on cy, nodes or edges change
 
+    useEffect(() => {
+        //Ensure cytoscape zoom and context state are synchronised
+        if (cy?.zoom() !== zoomLevel) {
+            cy?.zoom(zoomLevel);
+        }
+    }, [zoomLevel]);
+
     return (
         <div className="relative flex m-auto border">
             {title && (

calm-visualizer/src/components/navbar/Navbar.css

@@ -0,0 +1,8 @@
+.zoom-button {
+    border: solid;
+    border-width: 1px;
+}
+
+.zoom-button:hover {
+    background-color: aliceblue;
+}

calm-visualizer/src/components/navbar/Navbar.tsx

@@ -1,4 +1,6 @@
-import React from 'react';
+import './Navbar.css'
+import React, { useContext } from 'react';
+import { ZoomContext } from '../zoom-context.provider';
 
 interface NavbarProps {
     handleUpload: (instanceFile: File) => void;
@@ -16,6 +18,23 @@ function Navbar({
     const upload = (file: File) => {
         handleUpload(file);
     };
+    const { zoomLevel, updateZoom } = useContext(ZoomContext);
+
+    function zoomIn() {
+        //Obtain percentage as integer
+        const currentPercentageZoom = Math.round(zoomLevel*100);
+        //Add 10% to the zoom or round to upper 10% interval
+        const newPercentageZoom = Math.floor(currentPercentageZoom/10)*10 + 10;
+        updateZoom(newPercentageZoom/100);
+    }
+
+    function zoomOut() {
+        //Obtain percentage as integer
+        const currentPercentageZoom = Math.round(zoomLevel*100);
+        //Subtract 10% from the zoom or round to lower 10% interval - but not less than zero
+        const newPercentageZoom = Math.max(Math.ceil(currentPercentageZoom/10)*10 - 10, 0);
+        updateZoom(newPercentageZoom/100);
+    }
 
     return (
         <div className="navbar bg-secondary text-secondary-content">
@@ -51,8 +70,13 @@ function Navbar({
 
                 {isGraphRendered && (
                     <>
-                        <div className="divider divider-horizontal"></div>
+                        <div className="divider divider-horizontal"></div>  
                         <div className="toggles menu-horizontal">
+                            <div className="label">
+                                <span className="label label-text">Zoom: {(zoomLevel*100).toFixed(0)}%</span>
+                                <button className='ms-1 ps-2 pe-2 zoom-button' onClick={zoomIn}>+</button>
+                                <button className='ms-1 ps-2 pe-2 zoom-button' onClick={zoomOut}>-</button>
+                            </div> 
                             <label className="label cursor-pointer">
                                 <span className="label label-text text-secondary-content">
                                     Connection Descriptions

calm-visualizer/src/components/zoom-context.provider.tsx

@@ -0,0 +1,28 @@
+import React, { createContext, useState } from 'react';
+
+type ZoomContextProps = {
+    zoomLevel: number,
+    updateZoom: (newZoomLevel: number) => void
+}
+
+type ZoomProviderProps = { children: React.ReactNode; };
+
+const ZoomContext = createContext<ZoomContextProps>({
+    zoomLevel: 1, updateZoom: () => {}
+});
+
+const ZoomProvider = ({children}: ZoomProviderProps) => {
+  const [zoomLevel, setZoomLevel] = useState(1);
+
+  const updateZoom = (newZoomLevel: number) => {
+    setZoomLevel(newZoomLevel);
+  };
+
+  return (
+    <ZoomContext.Provider value={{ zoomLevel, updateZoom }}>
+      {children}
+    </ZoomContext.Provider>
+  );
+};
+
+export { ZoomContext, ZoomProvider };