feat(desktop): open chat file tools in pane + diffs.com UI for edit tool (#1828)

* feat(desktop): open chat file tools in pane and render edit diffs with diffs.com

* fix(desktop): support ast edit diffs and explicit file-open action

Author: Kitenite

apps/desktop/src/renderer/screens/main/components/WorkspaceView/ContentView/TabsContent/TabView/ChatMastraPane/ChatMastraInterface/ChatMastraInterface.tsx

@@ -44,7 +44,7 @@ function toErrorMessage(error: unknown): string | null {
 
 export function ChatMastraInterface({
 	sessionId,
-	workspaceId: _workspaceId,
+	workspaceId,
 	cwd,
 	onStartFreshSession,
 	onRawSnapshotChange,
@@ -222,6 +222,8 @@ export function ChatMastraInterface({
 					messages={mergedMessages}
 					isRunning={canAbort}
 					currentMessage={currentMessage ?? null}
+					workspaceId={workspaceId}
+					workspaceCwd={cwd}
 					activeTools={activeTools}
 					toolInputBuffers={toolInputBuffers}
 				/>

apps/desktop/src/renderer/screens/main/components/WorkspaceView/ContentView/TabsContent/TabView/ChatMastraPane/ChatMastraInterface/components/ChatMastraMessageList/ChatMastraMessageList.tsx

@@ -37,6 +37,8 @@ interface ChatMastraMessageListProps {
 	messages: MastraMessage[];
 	isRunning: boolean;
 	currentMessage: MastraMessage | null;
+	workspaceId: string;
+	workspaceCwd?: string;
 	activeTools: MastraActiveTools | undefined;
 	toolInputBuffers: MastraToolInputBuffers | undefined;
 }
@@ -225,10 +227,14 @@ function UserMessage({ message }: { message: MastraMessage }) {
 function AssistantMessage({
 	message,
 	isStreaming,
+	workspaceId,
+	workspaceCwd,
 	previewToolParts = [],
 }: {
 	message: MastraMessage;
 	isStreaming: boolean;
+	workspaceId: string;
+	workspaceCwd?: string;
 	previewToolParts?: ToolPart[];
 }) {
 	const nodes: ReactNode[] = [];
@@ -287,6 +293,8 @@ function AssistantMessage({
 						result,
 						isStreaming,
 					})}
+					workspaceId={workspaceId}
+					workspaceCwd={workspaceCwd}
 				/>,
 			);
 
@@ -303,6 +311,8 @@ function AssistantMessage({
 				<MastraToolCallBlock
 					key={`${message.id}-tool-result-${part.id}`}
 					part={toToolPartFromResult(part)}
+					workspaceId={workspaceId}
+					workspaceCwd={workspaceCwd}
 				/>,
 			);
 			continue;
@@ -327,6 +337,8 @@ function AssistantMessage({
 			<MastraToolCallBlock
 				key={`${message.id}-tool-preview-${previewPart.toolCallId}`}
 				part={previewPart}
+				workspaceId={workspaceId}
+				workspaceCwd={workspaceCwd}
 			/>,
 		);
 	}
@@ -350,6 +362,8 @@ export function ChatMastraMessageList({
 	messages,
 	isRunning,
 	currentMessage,
+	workspaceId,
+	workspaceCwd,
 	activeTools,
 	toolInputBuffers,
 }: ChatMastraMessageListProps) {
@@ -392,6 +406,8 @@ export function ChatMastraMessageList({
 							<AssistantMessage
 								key={message.id}
 								message={message}
+								workspaceId={workspaceId}
+								workspaceCwd={workspaceCwd}
 								isStreaming={false}
 								previewToolParts={[]}
 							/>
@@ -402,6 +418,8 @@ export function ChatMastraMessageList({
 					<AssistantMessage
 						key={`current-${currentMessage.id}`}
 						message={currentMessage}
+						workspaceId={workspaceId}
+						workspaceCwd={workspaceCwd}
 						isStreaming
 						previewToolParts={previewToolParts}
 					/>
@@ -428,6 +446,8 @@ export function ChatMastraMessageList({
 									<MastraToolCallBlock
 										key={`tool-preview-${part.toolCallId}`}
 										part={part}
+										workspaceId={workspaceId}
+										workspaceCwd={workspaceCwd}
 									/>
 								))}
 							</MessageContent>

apps/desktop/src/renderer/screens/main/components/WorkspaceView/ContentView/TabsContent/TabView/ChatPane/ChatInterface/components/MastraToolCallBlock/MastraToolCallBlock.tsx

@@ -5,7 +5,10 @@ import { WebFetchTool } from "@superset/ui/ai-elements/web-fetch-tool";
 import { WebSearchTool } from "@superset/ui/ai-elements/web-search-tool";
 import { getToolName } from "ai";
 import { FileIcon, FolderIcon, MessageCircleQuestionIcon } from "lucide-react";
+import { useCallback } from "react";
+import { useTabsStore } from "renderer/stores/tabs/store";
 import { READ_ONLY_TOOLS } from "../../constants";
+import { normalizeWorkspaceFilePath } from "../../utils/file-paths";
 import type { ToolPart } from "../../utils/tool-helpers";
 import {
 	getArgs,
@@ -14,24 +17,42 @@ import {
 	toWsToolState,
 } from "../../utils/tool-helpers";
 import { ReadOnlyToolCall } from "../ReadOnlyToolCall";
+import { EditToolExpandedDiff } from "./components/EditToolExpandedDiff";
 import { GenericToolCall } from "./components/GenericToolCall";
 
 interface MastraToolCallBlockProps {
 	part: ToolPart;
+	workspaceId?: string;
+	workspaceCwd?: string;
 	onAnswer?: (toolCallId: string, answers: Record<string, string>) => void;
 }
 
 export function MastraToolCallBlock({
 	part,
+	workspaceId,
+	workspaceCwd,
 	onAnswer,
 }: MastraToolCallBlockProps) {
 	const args = getArgs(part);
 	const result = getResult(part);
 	const state = toWsToolState(part);
 	const toolName = normalizeToolName(getToolName(part));
+	const addFileViewerPane = useTabsStore((store) => store.addFileViewerPane);
 	const toolDisplayName = toolName
 		.replace("mastra_workspace_", "")
 		.replaceAll("_", " ");
+	const openFileInPane = useCallback(
+		(filePath: string) => {
+			if (!workspaceId) return;
+			const normalizedPath = normalizeWorkspaceFilePath({
+				filePath,
+				workspaceRoot: workspaceCwd,
+			});
+			if (!normalizedPath) return;
+			addFileViewerPane(workspaceId, { filePath: normalizedPath });
+		},
+		[addFileViewerPane, workspaceCwd, workspaceId],
+	);
 
 	const outputObject =
 		typeof result.output === "object" && result.output !== null
@@ -64,6 +85,17 @@ export function MastraToolCallBlock({
 		return undefined;
 	};
 
+	const toRecord = (value: unknown): Record<string, unknown> | undefined => {
+		if (typeof value === "object" && value !== null && !Array.isArray(value)) {
+			return value as Record<string, unknown>;
+		}
+		return undefined;
+	};
+
+	const getFilePath = (...values: unknown[]): string => {
+		return firstText(...values) ?? "";
+	};
+
 	const toNumber = (value: unknown): number | undefined => {
 		if (typeof value === "number" && Number.isFinite(value)) return value;
 		if (typeof value === "string" && value.trim().length > 0) {
@@ -151,36 +183,141 @@ export function MastraToolCallBlock({
 
 	// --- Write file → FileDiffTool (write mode) ---
 	if (toolName === "mastra_workspace_write_file") {
-		const filePath = String(
-			args.path ?? args.filePath ?? args.relative_workspace_path ?? "",
+		const filePath = getFilePath(
+			args.path,
+			args.filePath,
+			args.file_path,
+			args.relative_workspace_path,
+			args.relativePath,
+			args.file,
+			args.filename,
+			toRecord(args.target)?.path,
 		);
 		const content = String(args.content ?? args.data ?? "");
 		return (
 			<FileDiffTool
 				filePath={filePath}
 				content={content}
 				isWriteMode
+				onFilePathClick={openFileInPane}
 				state={state}
 			/>
 		);
 	}
 
 	// --- Edit file → FileDiffTool (diff mode) ---
-	if (toolName === "mastra_workspace_edit_file") {
-		const filePath = String(
-			args.path ?? args.filePath ?? args.relative_workspace_path ?? "",
-		);
-		const oldString = String(
-			args.oldString ?? args.old_string ?? args.old_str ?? "",
+	if (
+		toolName === "mastra_workspace_edit_file" ||
+		toolName === "ast_smart_edit"
+	) {
+		const editArgs = toRecord(args.edit);
+		const filePath = getFilePath(
+			args.path,
+			args.filePath,
+			args.file_path,
+			args.relative_workspace_path,
+			args.relativePath,
+			args.file,
+			args.filename,
+			args.file_name,
+			args.target_file,
+			args.target_path,
+			args.targetPath,
+			editArgs?.path,
+			editArgs?.filePath,
+			editArgs?.file_path,
+			toRecord(args.target)?.path,
 		);
-		const newString = String(
-			args.newString ?? args.new_string ?? args.new_str ?? "",
+		const oldString =
+			firstText(
+				args.oldString,
+				args.old_string,
+				args.old_str,
+				args.oldText,
+				args.old_text,
+				args.oldCode,
+				args.old_code,
+				args.before,
+				args.find,
+				args.search,
+				args.original,
+				args.previous,
+				args.from,
+				editArgs?.oldString,
+				editArgs?.old_string,
+				editArgs?.oldText,
+				editArgs?.before,
+				outputObject?.oldString,
+				outputObject?.old_string,
+				nestedResultObject?.oldString,
+				nestedResultObject?.old_string,
+			) ?? "";
+		const newString =
+			firstText(
+				args.newString,
+				args.new_string,
+				args.new_str,
+				args.newText,
+				args.new_text,
+				args.newCode,
+				args.new_code,
+				args.after,
+				args.replace,
+				args.replacement,
+				args.updated,
+				args.to,
+				editArgs?.newString,
+				editArgs?.new_string,
+				editArgs?.newText,
+				editArgs?.after,
+				outputObject?.newString,
+				outputObject?.new_string,
+				nestedResultObject?.newString,
+				nestedResultObject?.new_string,
+			) ?? "";
+
+		const structuredPatchValue =
+			(Array.isArray(result.structuredPatch)
+				? result.structuredPatch
+				: Array.isArray(outputObject?.structuredPatch)
+					? outputObject?.structuredPatch
+					: Array.isArray(nestedResultObject?.structuredPatch)
+						? nestedResultObject?.structuredPatch
+						: undefined) ??
+			(Array.isArray(result.structured_patch)
+				? result.structured_patch
+				: Array.isArray(outputObject?.structured_patch)
+					? outputObject?.structured_patch
+					: Array.isArray(nestedResultObject?.structured_patch)
+						? nestedResultObject?.structured_patch
+						: undefined);
+		const structuredPatch = structuredPatchValue?.filter(
+			(hunk): hunk is { lines: string[] } => {
+				return Boolean(
+					typeof hunk === "object" &&
+						hunk !== null &&
+						Array.isArray((hunk as { lines?: unknown }).lines),
+				);
+			},
 		);
 		return (
 			<FileDiffTool
 				filePath={filePath}
 				oldString={oldString}
 				newString={newString}
+				structuredPatch={structuredPatch}
+				onFilePathClick={openFileInPane}
+				renderExpandedContent={
+					oldString || newString
+						? () => (
+								<EditToolExpandedDiff
+									filePath={filePath}
+									oldString={oldString}
+									newString={newString}
+								/>
+							)
+						: undefined
+				}
 				state={state}
 			/>
 		);
@@ -247,7 +384,7 @@ export function MastraToolCallBlock({
 
 	// --- Read-only exploration tools ---
 	if (READ_ONLY_TOOLS.has(toolName)) {
-		return <ReadOnlyToolCall part={part} />;
+		return <ReadOnlyToolCall part={part} onOpenFileInPane={openFileInPane} />;
 	}
 
 	// --- Destructive workspace tools ---

apps/desktop/src/renderer/screens/main/components/WorkspaceView/ContentView/TabsContent/TabView/ChatPane/ChatInterface/components/MastraToolCallBlock/components/EditToolExpandedDiff/EditToolExpandedDiff.tsx

@@ -0,0 +1,35 @@
+import { LightDiffViewer } from "renderer/screens/main/components/WorkspaceView/ChangesContent/components/LightDiffViewer";
+import { useChangesStore } from "renderer/stores/changes";
+import type { FileContents } from "shared/changes-types";
+
+interface EditToolExpandedDiffProps {
+	filePath: string;
+	oldString: string;
+	newString: string;
+}
+
+export function EditToolExpandedDiff({
+	filePath,
+	oldString,
+	newString,
+}: EditToolExpandedDiffProps) {
+	const viewMode = useChangesStore((state) => state.viewMode);
+	const hideUnchangedRegions = useChangesStore(
+		(state) => state.hideUnchangedRegions,
+	);
+
+	const contents: FileContents = {
+		original: oldString,
+		modified: newString,
+		language: "text",
+	};
+
+	return (
+		<LightDiffViewer
+			contents={contents}
+			viewMode={viewMode}
+			hideUnchangedRegions={hideUnchangedRegions}
+			filePath={filePath}
+		/>
+	);
+}

apps/desktop/src/renderer/screens/main/components/WorkspaceView/ContentView/TabsContent/TabView/ChatPane/ChatInterface/components/MastraToolCallBlock/components/EditToolExpandedDiff/index.ts

@@ -0,0 +1 @@
+export { EditToolExpandedDiff } from "./EditToolExpandedDiff";