feat: Make splits resizable

apps/client/src/services/resizer.ts

@@ -10,6 +10,10 @@ let leftInstance: ReturnType<typeof Split> | null;
 let rightPaneWidth: number;
 let rightInstance: ReturnType<typeof Split> | null;
 
+const noteSplitMap = new Map<string[], ReturnType<typeof Split> | undefined>(); // key: a group of ntxIds, value: the corresponding Split instance
+const noteSplitRafMap = new Map<string[], number>();
+let splitNoteContainer: HTMLElement | undefined;
+
 function setupLeftPaneResizer(leftPaneVisible: boolean) {
     if (leftInstance) {
         leftInstance.destroy();
@@ -83,7 +87,94 @@ function setupRightPaneResizer() {
     }
 }
 
+function findKeyByNtxId(ntxId: string): string[] | undefined {
+    // Find the corresponding key in noteSplitMap based on ntxId
+    for (const key of noteSplitMap.keys()) {
+        if (key.includes(ntxId)) return key;
+    }
+    return undefined;
+}
+
+function setupNoteSplitResizer(ntxIds: string[]) {
+    let targetNtxIds: string[] | undefined;
+    for (const ntxId of ntxIds) {
+        targetNtxIds = findKeyByNtxId(ntxId);
+        if (targetNtxIds) break; 
+    }
+
+    if (targetNtxIds) {
+        noteSplitMap.get(targetNtxIds)?.destroy();
+        for (const id of ntxIds) {
+            if (!targetNtxIds.includes(id)) {
+                targetNtxIds.push(id)
+            };
+        }
+    } else {
+        targetNtxIds = [...ntxIds];
+    }
+    noteSplitMap.set(targetNtxIds, undefined);
+    createSplitInstance(targetNtxIds);
+}
+
+
+function delNoteSplitResizer(ntxIds: string[]) {
+    let targetNtxIds = findKeyByNtxId(ntxIds[0]);
+
+    if (targetNtxIds) {
+        noteSplitMap.get(targetNtxIds)?.destroy();
+        noteSplitMap.delete(targetNtxIds);
+        targetNtxIds = targetNtxIds.filter(id => !ntxIds.includes(id));
+    }
+    if (targetNtxIds && targetNtxIds.length >= 2) {
+        noteSplitMap.set(targetNtxIds, undefined);
+        createSplitInstance(targetNtxIds);
+    }
+}
+
+function moveNoteSplitResizer(ntxId: string) {
+    const targetNtxIds = findKeyByNtxId(ntxId);
+
+    if (targetNtxIds) {
+        noteSplitMap.get(targetNtxIds)?.destroy();
+        noteSplitMap.set(targetNtxIds, undefined);
+    }
+
+    if (targetNtxIds) {
+        createSplitInstance(targetNtxIds);
+    }
+}
+
+function createSplitInstance(targetNtxIds: string[]) {
+    const prevRafId = noteSplitRafMap.get(targetNtxIds);
+    if (prevRafId) {
+        cancelAnimationFrame(prevRafId);
+    }
+
+    const rafId = requestAnimationFrame(() => {
+        if (!splitNoteContainer){
+            splitNoteContainer =  $("#center-pane").find(".split-note-container-widget")[0];
+        }
+        const splitPanels: HTMLElement[] = [];
+        for (const el of splitNoteContainer.querySelectorAll(':scope > .note-split')) {
+            const dataId = el.getAttribute('data-ntx-id');
+            if (dataId && targetNtxIds.includes(dataId)) {
+                splitPanels.push(el as HTMLElement);
+            }
+        }
+        const splitInstance = Split(splitPanels, {
+            gutterSize: DEFAULT_GUTTER_SIZE,
+            minSize: 150,
+        });
+        noteSplitMap.set(targetNtxIds, splitInstance);
+        noteSplitRafMap.delete(targetNtxIds);
+    });
+    noteSplitRafMap.set(targetNtxIds, rafId);
+}
+
 export default {
     setupLeftPaneResizer,
-    setupRightPaneResizer
+    setupRightPaneResizer,
+    setupNoteSplitResizer,
+    delNoteSplitResizer,
+    moveNoteSplitResizer
 };

apps/client/src/stylesheets/style.css

@@ -1171,6 +1171,10 @@ a.external:not(.no-arrow):after, a[href^="http://"]:not(.no-arrow):after, a[href
     cursor: row-resize;
 }
 
+.hidden-ext.note-split + .gutter {
+    display: none;
+}
+
 #context-menu-cover.show {
     position: fixed;
     top: 0;
@@ -1700,7 +1704,6 @@ body:not(.mobile) #launcher-pane.horizontal .dropdown-submenu > .dropdown-menu {
 }
 
 .note-split {
-    flex-basis: 0; /* so that each split has same width */
     margin-left: auto;
     margin-right: auto;
 }

apps/client/src/stylesheets/theme-next/shell.css

@@ -90,7 +90,7 @@ body.background-effects.zen #root-widget {
  * Gutter
  */
 
- .gutter {
+.gutter {
     background: var(--gutter-color) !important;
     transition: background 150ms ease-out;
 }
@@ -1092,6 +1092,11 @@ body.layout-vertical .tab-row-widget-is-sorting .note-tab.note-tab-is-dragging .
     /* will-change: opacity; -- causes some weird artifacts to the note menu in split view */
 }
 
+.split-note-container-widget > .gutter {
+    background: var(--root-background) !important;
+    transition: background 150ms ease-out;
+}
+
 /*
  * Ribbon & note header
  */
@@ -1100,10 +1105,6 @@ body.layout-vertical .tab-row-widget-is-sorting .note-tab.note-tab-is-dragging .
     margin-bottom: 0 !important;
 }
 
-.note-split:not(.hidden-ext) + .note-split:not(.hidden-ext) {
-    border-left: 4px solid var(--root-background);
-}
-
 @keyframes note-entrance {
     from {
         opacity: 0;

apps/client/src/widgets/containers/split_note_container.ts

@@ -2,6 +2,7 @@ import FlexContainer from "./flex_container.js";
 import appContext, { type CommandData, type CommandListenerData, type EventData, type EventNames, type NoteSwitchedContext } from "../../components/app_context.js";
 import type BasicWidget from "../basic_widget.js";
 import type NoteContext from "../../components/note_context.js";
+import splitService from "../../services/resizer.js";
 
 interface NoteContextEvent {
     noteContext: NoteContext;
@@ -51,6 +52,10 @@ export default class SplitNoteContainer extends FlexContainer<SplitNoteWidget> {
         await widget.handleEvent("setNoteContext", { noteContext });
 
         this.child(widget);
+
+        if (noteContext.mainNtxId && noteContext.ntxId) {
+            splitService.setupNoteSplitResizer([noteContext.mainNtxId,noteContext.ntxId]);
+        }
     }
 
     async openNewNoteSplitEvent({ ntxId, notePath, hoistedNoteId, viewScope }: EventData<"openNewNoteSplit">) {
@@ -94,9 +99,11 @@ export default class SplitNoteContainer extends FlexContainer<SplitNoteWidget> {
         }
     }
 
-    closeThisNoteSplitCommand({ ntxId }: CommandListenerData<"closeThisNoteSplit">) {
+    async closeThisNoteSplitCommand({ ntxId }: CommandListenerData<"closeThisNoteSplit">) {
         if (ntxId) {
-            appContext.tabManager.removeNoteContext(ntxId);
+            await appContext.tabManager.removeNoteContext(ntxId);
+            
+            splitService.delNoteSplitResizer([ntxId]);
         }
     }
 
@@ -136,6 +143,8 @@ export default class SplitNoteContainer extends FlexContainer<SplitNoteWidget> {
 
         // activate context that now contains the original note
         await appContext.tabManager.activateNoteContext(isMovingLeft ? ntxIds[leftIndex + 1] : ntxIds[leftIndex]);
+
+        splitService.moveNoteSplitResizer(ntxIds[leftIndex]);
     }
 
     activeContextChangedEvent() {
@@ -154,6 +163,8 @@ export default class SplitNoteContainer extends FlexContainer<SplitNoteWidget> {
 
             delete this.widgets[ntxId];
         }
+
+        splitService.delNoteSplitResizer(ntxIds);
     }
 
     contextsReopenedEvent({ ntxId, afterNtxId }: EventData<"contextsReopened">) {