refactor(texteditor): lazy load heavy extensions and general optimization

contentcuration/contentcuration/frontend/channelEdit/components/AssessmentItemEditor/AssessmentItemEditor.vue

@@ -127,6 +127,7 @@
   import translator from '../../translator';
   import { updateAnswersToQuestionType, assessmentItemKey } from '../../utils';
   import { AssessmentItemTypeLabels } from '../../constants';
+  import EditorImageProcessor from 'shared/views/TipTapEditor/TipTapEditor/services/imageService';
   import {
     ContentModalities,
     AssessmentItemTypes,
@@ -136,7 +137,6 @@
   import ErrorList from 'shared/views/ErrorList/ErrorList';
   import DropdownWrapper from 'shared/views/form/DropdownWrapper';
   import TipTapEditor from 'shared/views/TipTapEditor/TipTapEditor/TipTapEditor.vue';
-  import EditorImageProcessor from 'shared/views/TipTapEditor/TipTapEditor/services/imageService';
 
   export default {
     name: 'AssessmentItemEditor',

contentcuration/contentcuration/frontend/shared/views/TipTapEditor/TipTapEditor/TipTapEditorStrings.js

@@ -299,6 +299,10 @@ const MESSAGES = {
     message: 'Special Characters',
     context: 'Title for the menu containing special characters and mathematical symbols.',
   },
+  loadingFormulas: {
+    message: 'Loading math editor',
+    context: 'Text displayed while the math editor is being loaded.',
+  },
 
   // Error Messages
   errorUploadingImage: {

contentcuration/contentcuration/frontend/shared/views/TipTapEditor/TipTapEditor/components/EditorToolbar.vue

@@ -135,11 +135,13 @@
     <!-- More dropdown - only visible when there are overflow categories -->
     <div
       v-if="overflowCategories.length > 0"
+      ref="moreDropdownContainer"
       class="more-dropdown-container"
       role="group"
       :aria-label="'More options'"
     >
       <ToolbarButton
+        ref="moreButton"
         :title="'More options'"
         :icon="require('../../assets/icon-chevron-down.svg')"
         :is-active="isMoreDropdownOpen"
@@ -150,8 +152,9 @@
       />
 
       <div
-        v-if="isMoreDropdownOpen"
+        v-show="isMoreDropdownOpen"
         id="more-options-menu"
+        ref="moreDropdown"
         class="more-dropdown"
         role="menu"
         :aria-label="'Additional formatting options'"
@@ -302,6 +305,9 @@
     },
     setup(props, { emit }) {
       const toolbarRef = ref(null);
+      const moreButton = ref(null);
+      const moreDropdown = ref(null);
+      const moreDropdownContainer = ref(null);
       const isMoreDropdownOpen = ref(false);
       const toolbarWidth = ref(0);
 
@@ -360,20 +366,24 @@
 
       const updateToolbarWidth = () => {
         if (toolbarRef.value) {
-          toolbarWidth.value = toolbarRef.value.offsetWidth;
+          // Batch layout reads in next frame
+          requestAnimationFrame(() => {
+            toolbarWidth.value = toolbarRef.value.offsetWidth;
+          });
         }
       };
 
       const handleResize = entries => {
-        setTimeout(() => {
+        // Use ResizeObserver data directly - no DOM reading
+        requestAnimationFrame(() => {
           for (const entry of entries) {
             toolbarWidth.value = entry.contentRect.width;
           }
-        }, 0);
+        });
       };
 
       const handleWindowResize = () => {
-        setTimeout(updateToolbarWidth, 0);
+        requestAnimationFrame(updateToolbarWidth);
       };
 
       const onToolClick = (tool, event) => {
@@ -405,14 +415,11 @@
           isMoreDropdownOpen.value = false;
           // Return focus to the more button
           await nextTick();
-          const moreButton = toolbarRef.value?.querySelector(
-            '.more-dropdown-container [role="button"]',
-          );
-          moreButton?.focus();
+          moreButton.value?.$el?.focus();
         } else if (event.key === 'ArrowDown' || event.key === 'ArrowUp') {
           event.preventDefault();
           const menuItems = Array.from(
-            event.currentTarget.querySelectorAll('[role="menuitem"]:not(:disabled)'),
+            moreDropdown.value?.querySelectorAll('[role="menuitem"]:not(:disabled)') || [],
           );
           const currentIndex = menuItems.indexOf(document.activeElement);
 
@@ -429,28 +436,29 @@
 
       // Close dropdown when clicking outside
       const handleClickOutside = event => {
-        const dropdown = event.target.closest('.more-dropdown-container');
-        if (!dropdown) {
+        if (moreDropdownContainer.value && !moreDropdownContainer.value.contains(event.target)) {
           isMoreDropdownOpen.value = false;
         }
       };
 
       onMounted(async () => {
         await nextTick();
 
-        // Initial width measurement
-        updateToolbarWidth();
+        // Initial width measurement in next frame
+        requestAnimationFrame(() => {
+          updateToolbarWidth();
+        });
 
         // Set up resize observer
         if (toolbarRef.value && window.ResizeObserver) {
           resizeObserver = new ResizeObserver(handleResize);
           resizeObserver.observe(toolbarRef.value);
         } else {
-          // Fallback to window resize listener
-          window.addEventListener('resize', handleWindowResize);
+          // Fallback to window resize listener with passive flag
+          window.addEventListener('resize', handleWindowResize, { passive: true });
         }
 
-        document.addEventListener('click', handleClickOutside);
+        document.addEventListener('click', handleClickOutside, { passive: true });
       });
 
       onUnmounted(() => {
@@ -464,6 +472,9 @@
 
       return {
         toolbarRef,
+        moreButton,
+        moreDropdown,
+        moreDropdownContainer,
         isMoreDropdownOpen,
         visibleCategories,
         overflowCategories,

contentcuration/contentcuration/frontend/shared/views/TipTapEditor/TipTapEditor/components/image/ImageNodeView.vue

@@ -2,6 +2,7 @@
 
   <NodeViewWrapper class="image-node-wrapper">
     <div
+      ref="containerRef"
       class="image-node-view"
       :class="{ 'is-selected': selected && editor.isEditable }"
       :style="{ width: styleWidth }"
@@ -47,6 +48,7 @@
 
       <div
         v-if="editor.isEditable"
+        ref="resizeHandleRef"
         class="resize-handle"
         tabindex="0"
         role="slider"
@@ -74,13 +76,18 @@
     components: {
       NodeViewWrapper,
     },
+
     setup(props) {
       const width = ref(props.node.attrs.width || null);
       const height = ref(props.node.attrs.height || null);
       const imageRef = ref(null);
+      const containerRef = ref(null);
+      const resizeHandleRef = ref(null);
       const naturalAspectRatio = ref(null);
       const minWidth = 50;
       const compactThreshold = 200;
+      const debounceTimer = null;
+      let resizeListeners = null;
 
       // Create debounced version of saveSize function
       const debouncedSaveSize = _.debounce(() => {
@@ -149,6 +156,7 @@
       };
 
       const isRtl = computed(() => {
+        // Cache the RTL check result to avoid repeated DOM traversal
         return props.editor.view.dom.closest('[dir="rtl"]') !== null;
       });
 
@@ -176,7 +184,7 @@
 
       const onResizeStart = startEvent => {
         const startX = startEvent.clientX;
-        const startWidth = width.value || startEvent.target.parentElement.offsetWidth;
+        const startWidth = width.value || containerRef.value.offsetWidth;
 
         const onMouseMove = moveEvent => {
           const deltaX = moveEvent.clientX - startX;
@@ -186,23 +194,39 @@
             : startWidth + deltaX; // In LTR, moving right should increase width
 
           const clampedWidth = Math.max(minWidth, newWidth);
-          width.value = clampedWidth;
-          height.value = calculateProportionalHeight(clampedWidth);
+
+          // Batch DOM updates
+          requestAnimationFrame(() => {
+            width.value = clampedWidth;
+            height.value = calculateProportionalHeight(clampedWidth);
+          });
         };
 
         const onMouseUp = () => {
-          document.removeEventListener('mousemove', onMouseMove);
-          document.removeEventListener('mouseup', onMouseUp);
+          // Clean up listeners
+          if (resizeListeners) {
+            document.removeEventListener('mousemove', resizeListeners.move);
+            document.removeEventListener('mouseup', resizeListeners.up);
+            resizeListeners = null;
+          }
           saveSize();
         };
 
-        document.addEventListener('mousemove', onMouseMove);
-        document.addEventListener('mouseup', onMouseUp);
+        // Store listeners for proper cleanup
+        resizeListeners = {
+          move: onMouseMove,
+          up: onMouseUp,
+        };
+
+        // Use passive listeners where possible
+        document.addEventListener('mousemove', onMouseMove, { passive: true });
+        document.addEventListener('mouseup', onMouseUp, { passive: true });
       };
 
       const onResizeKeyDown = event => {
         const step = 10;
-        const currentWidth = width.value || event.target.parentElement.offsetWidth;
+        // Use ref instead of DOM query
+        const currentWidth = width.value || containerRef.value.offsetWidth;
         let newWidth = currentWidth;
 
         // Invert keyboard controls for RTL
@@ -214,7 +238,8 @@
         } else if (event.key === leftKey) {
           newWidth = currentWidth - step;
         } else if (event.key === 'Escape' || event.key === 'Enter') {
-          event.target.blur();
+          // Use ref instead of DOM query
+          resizeHandleRef.value?.blur();
           const endPosition = props.getPos() + props.node.nodeSize;
           props.editor.chain().focus().insertContentAt(endPosition, { type: 'paragraph' }).run();
           return;
@@ -223,8 +248,12 @@
         }
 
         const clampedWidth = Math.max(minWidth, newWidth);
-        width.value = clampedWidth;
-        height.value = calculateProportionalHeight(clampedWidth);
+
+        // Batch DOM updates
+        requestAnimationFrame(() => {
+          width.value = clampedWidth;
+          height.value = calculateProportionalHeight(clampedWidth);
+        });
 
         debouncedSaveSize();
       };
@@ -251,13 +280,21 @@
       });
 
       onUnmounted(() => {
-        // Cancel any pending debounced calls
-        debouncedSaveSize.cancel();
+        clearTimeout(debounceTimer);
+
+        // Clean up any remaining resize listeners
+        if (resizeListeners) {
+          document.removeEventListener('mousemove', resizeListeners.move);
+          document.removeEventListener('mouseup', resizeListeners.up);
+          resizeListeners = null;
+        }
       });
 
       return {
         width,
         imageRef,
+        containerRef,
+        resizeHandleRef,
         styleWidth,
         onResizeStart,
         removeImage,