feat: reorder options

* fix: back button issue

* chore: add unit test

* fix : test cases

---------

Co-authored-by: Gaurav Tewari <tewarig@users.noreply.github.com>

frontend/src/lib/history.ts

@@ -1,4 +1,15 @@
 import { createBrowserHistory } from 'history';
 import { getBasePath } from 'utils/basePath';
 
-export default createBrowserHistory({ basename: getBasePath() });
+const history = createBrowserHistory({ basename: getBasePath() });
+
+let inAppPushCount = 0;
+history.listen((_, action) => {
+	if (action === 'PUSH') {
+		inAppPushCount += 1;
+	}
+});
+
+export const hasInAppHistory = (): boolean => inAppPushCount > 0;
+
+export default history;

frontend/src/pages/TraceDetailsV3/SpanDetailsPanel/DockModeSwitcher.tsx

@@ -0,0 +1,81 @@
+import { ReactNode } from 'react';
+import { Dock, PanelBottom, PanelRight } from '@signozhq/icons';
+import { ToggleGroup, ToggleGroupItem } from '@signozhq/ui/toggle-group';
+import {
+	TooltipContent,
+	TooltipProvider,
+	TooltipRoot,
+	TooltipTrigger,
+} from '@signozhq/ui/tooltip';
+
+import { SpanDetailVariant } from './constants';
+
+interface DockOption {
+	value: SpanDetailVariant;
+	icon: ReactNode;
+	tooltip: string;
+}
+
+const DOCK_OPTIONS: DockOption[] = [
+	{
+		value: SpanDetailVariant.DIALOG,
+		icon: <Dock size={14} />,
+		tooltip: 'Open as floating panel',
+	},
+	{
+		value: SpanDetailVariant.DOCKED,
+		icon: <PanelBottom size={14} />,
+		tooltip: 'Dock at the bottom',
+	},
+	{
+		value: SpanDetailVariant.DOCKED_RIGHT,
+		icon: <PanelRight size={14} />,
+		tooltip: 'Dock on the right',
+	},
+];
+
+interface DockModeSwitcherProps {
+	value: SpanDetailVariant;
+	onChange: (value: SpanDetailVariant) => void;
+	tooltipClassName?: string;
+}
+
+// Icon-segmented control for picking the Span Details panel dock mode.
+// The inner <span> wrap is load-bearing: TooltipTrigger asChild clones its
+// child and merges its own data-state, which would otherwise clobber
+// ToggleGroupItem's data-state="on"/"off" active styling.
+function DockModeSwitcher({
+	value,
+	onChange,
+	tooltipClassName,
+}: DockModeSwitcherProps): JSX.Element {
+	return (
+		<TooltipProvider>
+			<ToggleGroup
+				type="single"
+				value={value}
+				onChange={(v): void => {
+					if (v) {
+						onChange(v as SpanDetailVariant);
+					}
+				}}
+				size="sm"
+			>
+				{DOCK_OPTIONS.map((option) => (
+					<TooltipRoot key={option.value}>
+						<TooltipTrigger asChild>
+							<span>
+								<ToggleGroupItem value={option.value}>{option.icon}</ToggleGroupItem>
+							</span>
+						</TooltipTrigger>
+						<TooltipContent className={tooltipClassName}>
+							{option.tooltip}
+						</TooltipContent>
+					</TooltipRoot>
+				))}
+			</ToggleGroup>
+		</TooltipProvider>
+	);
+}
+
+export default DockModeSwitcher;

frontend/src/pages/TraceDetailsV3/SpanDetailsPanel/SpanDetailsPanel.tsx

@@ -1,25 +1,16 @@
 import { useCallback, useMemo } from 'react';
-import { Button } from '@signozhq/ui/button';
 import {
 	TabsContent,
 	TabsList,
 	TabsRoot,
 	TabsTrigger,
 } from '@signozhq/ui/tabs';
-import {
-	TooltipRoot,
-	TooltipContent,
-	TooltipProvider,
-	TooltipTrigger,
-} from '@signozhq/ui/tooltip';
 import {
 	Bookmark,
 	CalendarClock,
 	ChartColumnBig,
-	Dock,
 	Link2,
 	List,
-	PanelBottom,
 	ScrollText,
 	Timer,
 } from '@signozhq/icons';
@@ -61,6 +52,7 @@ import {
 	SpanDetailVariant,
 	VISIBLE_ACTIONS,
 } from './constants';
+import DockModeSwitcher from './DockModeSwitcher';
 import { useSpanAttributeActions } from './hooks/useSpanAttributeActions';
 import { useTracePinnedFields } from './hooks/useTracePinnedFields';
 import {
@@ -492,31 +484,14 @@ function SpanDetailsPanel({
 		];
 
 		if (onVariantChange) {
-			const isDocked = variant === SpanDetailVariant.DOCKED;
 			actions.push({
-				key: 'dock-toggle',
+				key: 'dock-mode',
 				component: (
-					<TooltipProvider>
-						<TooltipRoot>
-							<TooltipTrigger asChild>
-								<Button
-									variant="ghost"
-									size="icon"
-									color="secondary"
-									onClick={(): void =>
-										onVariantChange(
-											isDocked ? SpanDetailVariant.DIALOG : SpanDetailVariant.DOCKED,
-										)
-									}
-								>
-									{isDocked ? <Dock size={14} /> : <PanelBottom size={14} />}
-								</Button>
-							</TooltipTrigger>
-							<TooltipContent className={styles.dockToggleTooltip}>
-								{isDocked ? 'Open as floating panel' : 'Dock at the bottom'}
-							</TooltipContent>
-						</TooltipRoot>
-					</TooltipProvider>
+					<DockModeSwitcher
+						value={variant}
+						onChange={onVariantChange}
+						tooltipClassName={styles.dockToggleTooltip}
+					/>
 				),
 			});
 		}
@@ -553,7 +528,10 @@ function SpanDetailsPanel({
 		</>
 	);
 
-	if (variant === SpanDetailVariant.DOCKED) {
+	if (
+		variant === SpanDetailVariant.DOCKED ||
+		variant === SpanDetailVariant.DOCKED_RIGHT
+	) {
 		return <div className={styles.root}>{content}</div>;
 	}
 

frontend/src/pages/TraceDetailsV3/SpanDetailsPanel/constants.ts

@@ -22,6 +22,7 @@ export enum SpanDetailVariant {
 	DRAWER = 'drawer',
 	DIALOG = 'dialog',
 	DOCKED = 'docked',
+	DOCKED_RIGHT = 'right',
 }
 
 export const KEY_ATTRIBUTE_KEYS: Record<string, string[]> = {

frontend/src/pages/TraceDetailsV3/TraceDetailsHeader/TraceDetailsHeader.tsx

@@ -16,7 +16,7 @@ import { LOCALSTORAGE } from 'constants/localStorage';
 import ROUTES from 'constants/routes';
 import { convertTimeToRelevantUnit } from 'container/TraceDetail/utils';
 import dayjs from 'dayjs';
-import history from 'lib/history';
+import history, { hasInAppHistory } from 'lib/history';
 import {
 	ArrowLeft,
 	CalendarClock,
@@ -96,13 +96,7 @@ function TraceDetailsHeader({
 	}, [traceID]);
 
 	const handlePreviousBtnClick = useCallback((): void => {
-		const isSpaNavigate =
-			document.referrer &&
-			// oxlint-disable-next-line signoz/no-raw-absolute-path
-			new URL(document.referrer).origin === window.location.origin;
-		const hasBackHistory = window.history.length > 1;
-
-		if (isSpaNavigate && hasBackHistory) {
+		if (hasInAppHistory()) {
 			history.goBack();
 		} else {
 			history.push(ROUTES.TRACES_EXPLORER);
@@ -130,6 +124,7 @@ function TraceDetailsHeader({
 							size="md"
 							className={styles.backBtn}
 							onClick={handlePreviousBtnClick}
+							aria-label="Back"
 						>
 							<ArrowLeft size={14} />
 						</Button>

frontend/src/pages/TraceDetailsV3/TraceDetailsHeader/__tests__/TraceDetailsHeader.test.tsx

@@ -0,0 +1,60 @@
+import { fireEvent, screen } from '@testing-library/react';
+import ROUTES from 'constants/routes';
+import { render } from 'tests/test-utils';
+
+import TraceDetailsHeader from '../TraceDetailsHeader';
+
+const mockGoBack = jest.fn();
+const mockPush = jest.fn();
+const mockHasInAppHistory = jest.fn();
+
+jest.mock('lib/history', () => ({
+	__esModule: true,
+	default: {
+		goBack: (): void => mockGoBack(),
+		push: (path: string): void => mockPush(path),
+		replace: jest.fn(),
+		location: { pathname: '/', search: '' },
+		listen: (): (() => void) => (): void => undefined,
+	},
+	hasInAppHistory: (): boolean => mockHasInAppHistory(),
+}));
+
+const baseProps = {
+	filterMetadata: {
+		startTime: 0,
+		endTime: 1,
+		traceId: 'trace-123',
+	},
+	onFilteredSpansChange: jest.fn(),
+	isDataLoaded: false,
+};
+
+describe('TraceDetailsHeader – back button', () => {
+	beforeEach(() => {
+		mockGoBack.mockClear();
+		mockPush.mockClear();
+		mockHasInAppHistory.mockReset();
+	});
+
+	it('calls history.goBack() when there is in-app SPA history', () => {
+		mockHasInAppHistory.mockReturnValue(true);
+		render(<TraceDetailsHeader {...baseProps} />);
+
+		fireEvent.click(screen.getByRole('button', { name: /back/i }));
+
+		expect(mockGoBack).toHaveBeenCalledTimes(1);
+		expect(mockPush).not.toHaveBeenCalled();
+	});
+
+	it('pushes to the traces explorer route when there is no in-app SPA history', () => {
+		mockHasInAppHistory.mockReturnValue(false);
+		render(<TraceDetailsHeader {...baseProps} />);
+
+		fireEvent.click(screen.getByRole('button', { name: /back/i }));
+
+		expect(mockPush).toHaveBeenCalledTimes(1);
+		expect(mockPush).toHaveBeenCalledWith(ROUTES.TRACES_EXPLORER);
+		expect(mockGoBack).not.toHaveBeenCalled();
+	});
+});

frontend/src/pages/TraceDetailsV3/TraceDetailsV3.module.scss

@@ -4,13 +4,28 @@
 	flex-direction: column;
 }
 
+.layoutRow {
+	display: flex;
+	flex: 1;
+	min-height: 0;
+	overflow: hidden;
+}
+
 .content {
 	display: flex;
 	flex-direction: column;
 	flex: 1;
+	min-width: 0;
 	overflow: hidden;
 }
 
+.rightDock {
+	display: flex;
+	flex-direction: column;
+	border-left: 1px solid var(--l2-border);
+	min-width: 0;
+}
+
 // Shared Ant Collapse chrome reset for both the flamegraph and waterfall
 // collapse panels.
 .flameCollapse,

frontend/src/pages/TraceDetailsV3/index.tsx

@@ -242,9 +242,13 @@ function TraceDetailsV3(): JSX.Element {
 		() =>
 			(getLocalStorageKey(
 				LOCALSTORAGE.TRACE_DETAILS_SPAN_DETAILS_POSITION,
-			) as SpanDetailVariant) || SpanDetailVariant.DIALOG,
+			) as SpanDetailVariant) || SpanDetailVariant.DOCKED_RIGHT,
 	);
 
+	const RIGHT_DOCK_MIN = 480;
+	const RIGHT_DOCK_MAX = 720;
+	const [rightDockWidth, setRightDockWidth] = useState(RIGHT_DOCK_MIN);
+
 	const handleVariantChange = useCallback(
 		(newVariant: SpanDetailVariant): void => {
 			setLocalStorageKey(
@@ -291,7 +295,9 @@ function TraceDetailsV3(): JSX.Element {
 		(!!errorFetchingTraceData || !traceData?.payload?.spans?.length);
 
 	const isDocked = spanDetailVariant === SpanDetailVariant.DOCKED;
+	const isRightDocked = spanDetailVariant === SpanDetailVariant.DOCKED_RIGHT;
 	const isWaterfallDocked = panelState.isOpen && isDocked;
+	const showRightDock = panelState.isOpen && isRightDocked;
 
 	const waterfallChildren = (
 		<ResizableBox
@@ -332,94 +338,119 @@ function TraceDetailsV3(): JSX.Element {
 					<NoData />
 				) : (
 					<>
-						<div className={styles.content}>
-							<Collapse
-								// @ts-expect-error motion is passed through to rc-collapse to disable animation
-								motion={false}
-								activeKey={activeKeys.filter((k) => k === 'flame')}
-								onChange={(): void => handleCollapseChange('flame')}
-								size="small"
-								className={styles.flameCollapse}
-								items={[
-									{
-										key: 'flame',
-										label: (
-											<div className={styles.collapseLabel}>
-												<span className={styles.collapseTitle}>
-													Flame Graph
-													{traceData?.payload?.totalSpansCount &&
-														traceData.payload.totalSpansCount > FLAMEGRAPH_SPAN_LIMIT && (
-															<WarningPopover
-																message="The total span count exceeds the visualization limit. Displaying a sampled subset of spans in flamegraph."
-																placement="bottomLeft"
-															/>
-														)}
-												</span>
-												{traceData?.payload?.totalSpansCount ? (
-													<span className={styles.collapseCount}>
-														<span className={styles.collapseCountItem}>
-															<ChartNoAxesGantt size={13} />
-															Spans: {traceData.payload.totalSpansCount}
-														</span>
-														<span
-															className={cx(styles.collapseCountItem, {
-																[styles.hasErrors]: traceData.payload.totalErrorSpansCount > 0,
-															})}
-														>
-															<TriangleAlert size={13} />
-															Errors: {traceData.payload.totalErrorSpansCount ?? 0}
-														</span>
+						<div className={styles.layoutRow}>
+							<div className={styles.content}>
+								<Collapse
+									// @ts-expect-error motion is passed through to rc-collapse to disable animation
+									motion={false}
+									activeKey={activeKeys.filter((k) => k === 'flame')}
+									onChange={(): void => handleCollapseChange('flame')}
+									size="small"
+									className={styles.flameCollapse}
+									items={[
+										{
+											key: 'flame',
+											label: (
+												<div className={styles.collapseLabel}>
+													<span className={styles.collapseTitle}>
+														Flame Graph
+														{traceData?.payload?.totalSpansCount &&
+															traceData.payload.totalSpansCount > FLAMEGRAPH_SPAN_LIMIT && (
+																<WarningPopover
+																	message="The total span count exceeds the visualization limit. Displaying a sampled subset of spans in flamegraph."
+																	placement="bottomLeft"
+																/>
+															)}
 													</span>
-												) : null}
-											</div>
-										),
-										children: (
-											<ResizableBox defaultHeight={300} minHeight={100} maxHeight={400}>
-												<TraceFlamegraph
-													filteredSpanIds={filteredSpanIds}
-													isFilterActive={isFilterActive}
-													selectedSpan={selectedSpan}
-													totalSpansCount={totalSpansCount}
-												/>
-											</ResizableBox>
-										),
-									},
-								]}
-							/>
+													{traceData?.payload?.totalSpansCount ? (
+														<span className={styles.collapseCount}>
+															<span className={styles.collapseCountItem}>
+																<ChartNoAxesGantt size={13} />
+																Spans: {traceData.payload.totalSpansCount}
+															</span>
+															<span
+																className={cx(styles.collapseCountItem, {
+																	[styles.hasErrors]: traceData.payload.totalErrorSpansCount > 0,
+																})}
+															>
+																<TriangleAlert size={13} />
+																Errors: {traceData.payload.totalErrorSpansCount ?? 0}
+															</span>
+														</span>
+													) : null}
+												</div>
+											),
+											children: (
+												<ResizableBox defaultHeight={300} minHeight={100} maxHeight={400}>
+													<TraceFlamegraph
+														filteredSpanIds={filteredSpanIds}
+														isFilterActive={isFilterActive}
+														selectedSpan={selectedSpan}
+														totalSpansCount={totalSpansCount}
+													/>
+												</ResizableBox>
+											),
+										},
+									]}
+								/>
 
-							<Collapse
-								// @ts-expect-error motion is passed through to rc-collapse to disable animation
-								motion={false}
-								activeKey={activeKeys.filter((k) => k === 'waterfall')}
-								onChange={(): void => handleCollapseChange('waterfall')}
-								size="small"
-								className={cx(styles.waterfallCollapse, {
-									[styles.isDocked]: isWaterfallDocked,
-								})}
-								items={[
-									{
-										key: 'waterfall',
-										label: 'Waterfall',
-										children: activeKeys.includes('waterfall') ? waterfallChildren : null,
-									},
-								]}
-							/>
+								<Collapse
+									// @ts-expect-error motion is passed through to rc-collapse to disable animation
+									motion={false}
+									activeKey={activeKeys.filter((k) => k === 'waterfall')}
+									onChange={(): void => handleCollapseChange('waterfall')}
+									size="small"
+									className={cx(styles.waterfallCollapse, {
+										[styles.isDocked]: isWaterfallDocked,
+									})}
+									items={[
+										{
+											key: 'waterfall',
+											label: 'Waterfall',
+											children: activeKeys.includes('waterfall')
+												? waterfallChildren
+												: null,
+										},
+									]}
+								/>
 
-							{panelState.isOpen && isDocked && (
-								<div className={styles.dockedSpanDetails}>
+								{panelState.isOpen && isDocked && (
+									<div className={styles.dockedSpanDetails}>
+										<SpanDetailsPanel
+											panelState={panelState}
+											selectedSpan={selectedSpan}
+											variant={SpanDetailVariant.DOCKED}
+											onVariantChange={handleVariantChange}
+											traceStartTime={traceData?.payload?.startTimestampMillis}
+											traceEndTime={traceData?.payload?.endTimestampMillis}
+										/>
+									</div>
+								)}
+							</div>
+
+							{showRightDock && (
+								<ResizableBox
+									direction="horizontal"
+									handlePosition="start"
+									defaultWidth={rightDockWidth}
+									minWidth={RIGHT_DOCK_MIN}
+									maxWidth={RIGHT_DOCK_MAX}
+									onResize={setRightDockWidth}
+									className={styles.rightDock}
+								>
 									<SpanDetailsPanel
 										panelState={panelState}
 										selectedSpan={selectedSpan}
-										variant={SpanDetailVariant.DOCKED}
+										variant={SpanDetailVariant.DOCKED_RIGHT}
 										onVariantChange={handleVariantChange}
 										traceStartTime={traceData?.payload?.startTimestampMillis}
 										traceEndTime={traceData?.payload?.endTimestampMillis}
 									/>
-								</div>
+								</ResizableBox>
 							)}
 						</div>
 
-						{panelState.isOpen && !isDocked && (
+						{panelState.isOpen && spanDetailVariant === SpanDetailVariant.DIALOG && (
 							<SpanDetailsPanel
 								panelState={panelState}
 								selectedSpan={selectedSpan}

frontend/src/periscope/components/ResizableBox/ResizableBox.styles.scss

@@ -24,7 +24,6 @@
 		}
 
 		&--vertical {
-			bottom: 0;
 			left: 0;
 			right: 0;
 			height: 1px;
@@ -32,11 +31,26 @@
 		}
 
 		&--horizontal {
-			right: 0;
 			top: 0;
 			bottom: 0;
 			width: 1px;
 			cursor: col-resize;
 		}
+
+		&--vertical-end {
+			bottom: 0;
+		}
+
+		&--vertical-start {
+			top: 0;
+		}
+
+		&--horizontal-end {
+			right: 0;
+		}
+
+		&--horizontal-start {
+			left: 0;
+		}
 	}
 }

frontend/src/periscope/components/ResizableBox/ResizableBox.tsx

@@ -5,6 +5,10 @@ import './ResizableBox.styles.scss';
 export interface ResizableBoxProps {
 	children: React.ReactNode;
 	direction?: 'vertical' | 'horizontal';
+	// Which edge the resize handle sits on. 'end' = bottom (vertical) or right
+	// (horizontal); 'start' = top or left. Dragging the start handle towards the
+	// content shrinks it; away grows it.
+	handlePosition?: 'start' | 'end';
 	defaultHeight?: number;
 	minHeight?: number;
 	maxHeight?: number;
@@ -19,6 +23,7 @@ export interface ResizableBoxProps {
 function ResizableBox({
 	children,
 	direction = 'vertical',
+	handlePosition = 'end',
 	defaultHeight = 200,
 	minHeight = 50,
 	maxHeight = Infinity,
@@ -30,6 +35,7 @@ function ResizableBox({
 	className,
 }: ResizableBoxProps): JSX.Element {
 	const isHorizontal = direction === 'horizontal';
+	const isStartHandle = handlePosition === 'start';
 	const [size, setSize] = useState(isHorizontal ? defaultWidth : defaultHeight);
 	const containerRef = useRef<HTMLDivElement>(null);
 
@@ -40,10 +46,13 @@ function ResizableBox({
 			const startSize = size;
 			const min = isHorizontal ? minWidth : minHeight;
 			const max = isHorizontal ? maxWidth : maxHeight;
+			// Start-edge handle: pointer moving away from content (negative delta)
+			// grows the box, so invert the sign.
+			const deltaSign = isStartHandle ? -1 : 1;
 
 			const onMouseMove = (moveEvent: MouseEvent): void => {
 				const currentPos = isHorizontal ? moveEvent.clientX : moveEvent.clientY;
-				const delta = currentPos - startPos;
+				const delta = (currentPos - startPos) * deltaSign;
 				const newSize = Math.min(max, Math.max(min, startSize + delta));
 				setSize(newSize);
 				onResize?.(newSize);
@@ -61,7 +70,16 @@ function ResizableBox({
 			document.addEventListener('mousemove', onMouseMove);
 			document.addEventListener('mouseup', onMouseUp);
 		},
-		[size, isHorizontal, minWidth, maxWidth, minHeight, maxHeight, onResize],
+		[
+			size,
+			isHorizontal,
+			isStartHandle,
+			minWidth,
+			maxWidth,
+			minHeight,
+			maxHeight,
+			onResize,
+		],
 	);
 
 	const containerStyle = disabled
@@ -69,7 +87,11 @@ function ResizableBox({
 		: isHorizontal
 			? { width: size }
 			: { height: size };
-	const handleClass = `resizable-box__handle resizable-box__handle--${direction}`;
+	const handleClass = [
+		'resizable-box__handle',
+		`resizable-box__handle--${direction}`,
+		`resizable-box__handle--${direction}-${handlePosition}`,
+	].join(' ');
 
 	return (
 		<div