diff --git a/app/src/hooks/useFileNavigation.test.ts b/app/src/hooks/useFileNavigation.test.ts
index 5e6cc00..ab177be 100644
--- a/app/src/hooks/useFileNavigation.test.ts
+++ b/app/src/hooks/useFileNavigation.test.ts
@@ -62,9 +62,7 @@ describe('useFileNavigation', () => {
       });
 
       expect(mockLastOpenedFile.loadLastOpenedFile).toHaveBeenCalled();
-      expect(mockLastOpenedFile.saveLastOpenedFile).toHaveBeenCalledWith(
-        'documents/readme.md'
-      );
+      expect(mockLastOpenedFile.saveLastOpenedFile).not.toHaveBeenCalled();
     });
 
     it('stays with default file when no last opened file exists', async () => {
@@ -90,8 +88,11 @@ describe('useFileNavigation', () => {
         await result.current.handleFileSelect('notes/todo.md');
       });
 
-      expect(result.current.selectedFile).toBe('notes/todo.md');
-      expect(result.current.isNewFile).toBe(false);
+      await waitFor(() => {
+        expect(result.current.selectedFile).toBe('notes/todo.md');
+        expect(result.current.isNewFile).toBe(false);
+      });
+
       expect(mockLastOpenedFile.saveLastOpenedFile).toHaveBeenCalledWith(
         'notes/todo.md'
       );
@@ -109,7 +110,7 @@ describe('useFileNavigation', () => {
       expect(mockLastOpenedFile.saveLastOpenedFile).not.toHaveBeenCalled();
     });
 
-    it('handles empty string file selection', async () => {
+    it('handles empty string file selection with default file', async () => {
       const { result } = renderHook(() => useFileNavigation());
 
       await act(async () => {
@@ -121,6 +122,32 @@ describe('useFileNavigation', () => {
       expect(mockLastOpenedFile.saveLastOpenedFile).not.toHaveBeenCalled();
     });
 
+    it('preserves current selection when passed empty string with existing selection', async () => {
+      const { result } = renderHook(() => useFileNavigation());
+
+      // First select a valid file
+      await act(async () => {
+        await result.current.handleFileSelect('existing-file.md');
+      });
+
+      await waitFor(() => {
+        expect(result.current.selectedFile).toBe('existing-file.md');
+        expect(result.current.isNewFile).toBe(false);
+      });
+
+      vi.clearAllMocks();
+
+      // Now send empty string
+      await act(async () => {
+        await result.current.handleFileSelect('');
+      });
+
+      // Selection should be preserved
+      expect(result.current.selectedFile).toBe('existing-file.md');
+      expect(result.current.isNewFile).toBe(false);
+      expect(mockLastOpenedFile.saveLastOpenedFile).not.toHaveBeenCalled();
+    });
+
     it('handles different file path formats', async () => {
       const { result } = renderHook(() => useFileNavigation());
 
@@ -138,8 +165,11 @@ describe('useFileNavigation', () => {
           await result.current.handleFileSelect(filePath);
         });
 
-        expect(result.current.selectedFile).toBe(filePath);
-        expect(result.current.isNewFile).toBe(false);
+        await waitFor(() => {
+          expect(result.current.selectedFile).toBe(filePath);
+          expect(result.current.isNewFile).toBe(false);
+        });
+
         expect(mockLastOpenedFile.saveLastOpenedFile).toHaveBeenCalledWith(
           filePath
         );
@@ -155,16 +185,22 @@ describe('useFileNavigation', () => {
 
       const files = ['file1.md', 'file2.md', 'file3.md'];
 
-      await act(async () => {
-        await Promise.all(
-          files.map((file) => result.current.handleFileSelect(file))
-        );
+      // Use sequential state updates instead of Promise.all for more predictable results
+      for (const file of files) {
+        await act(async () => {
+          await result.current.handleFileSelect(file);
+        });
+      }
+
+      // After all updates, we should have the last file selected
+      await waitFor(() => {
+        expect(result.current.selectedFile).toBe(files[files.length - 1]);
+        expect(result.current.isNewFile).toBe(false);
       });
 
-      // Should end up with the last file (depending on async timing)
-      expect(files).toContain(result.current.selectedFile);
-      expect(result.current.isNewFile).toBe(false);
-      expect(mockLastOpenedFile.saveLastOpenedFile).toHaveBeenCalledTimes(3);
+      expect(mockLastOpenedFile.saveLastOpenedFile).toHaveBeenCalledTimes(
+        files.length
+      );
     });
 
     it('handles file selection errors gracefully', async () => {
@@ -179,8 +215,11 @@ describe('useFileNavigation', () => {
         await result.current.handleFileSelect('error-file.md');
       });
 
-      expect(result.current.selectedFile).toBe('error-file.md');
-      expect(result.current.isNewFile).toBe(false);
+      // Wait for state update despite the error
+      await waitFor(() => {
+        expect(result.current.selectedFile).toBe('error-file.md');
+        expect(result.current.isNewFile).toBe(false);
+      });
     });
   });
 
@@ -324,15 +363,22 @@ describe('useFileNavigation', () => {
         await result.current.handleFileSelect('real-file.md');
       });
 
-      expect(result.current.isNewFile).toBe(false);
+      // Wait for state to update
+      await waitFor(() => {
+        expect(result.current.selectedFile).toBe('real-file.md');
+        expect(result.current.isNewFile).toBe(false);
+      });
 
       // Go back to null (should default to default file)
       await act(async () => {
         await result.current.handleFileSelect(null);
       });
 
-      expect(result.current.selectedFile).toBe(DEFAULT_FILE.path);
-      expect(result.current.isNewFile).toBe(true);
+      // Wait for state to update again
+      await waitFor(() => {
+        expect(result.current.selectedFile).toBe(DEFAULT_FILE.path);
+        expect(result.current.isNewFile).toBe(true);
+      });
     });
 
     it('maintains correct isNewFile state for regular files', async () => {
@@ -345,8 +391,11 @@ describe('useFileNavigation', () => {
           await result.current.handleFileSelect(file);
         });
 
-        expect(result.current.selectedFile).toBe(file);
-        expect(result.current.isNewFile).toBe(false);
+        // Wait for each file selection to complete
+        await waitFor(() => {
+          expect(result.current.selectedFile).toBe(file);
+          expect(result.current.isNewFile).toBe(false);
+        });
       }
     });
   });
@@ -414,8 +463,10 @@ describe('useFileNavigation', () => {
       });
 
       // State should still be updated despite save error
-      expect(result.current.selectedFile).toBe('test-file.md');
-      expect(result.current.isNewFile).toBe(false);
+      await waitFor(() => {
+        expect(result.current.selectedFile).toBe('test-file.md');
+        expect(result.current.isNewFile).toBe(false);
+      });
     });
   });
 });
diff --git a/app/src/hooks/useFileNavigation.ts b/app/src/hooks/useFileNavigation.ts
index 3240c19..2218461 100644
--- a/app/src/hooks/useFileNavigation.ts
+++ b/app/src/hooks/useFileNavigation.ts
@@ -17,35 +17,55 @@ export const useFileNavigation = (): UseFileNavigationResult => {
 
   const handleFileSelect = useCallback(
     async (filePath: string | null): Promise<void> => {
-      const newPath = filePath || DEFAULT_FILE.path;
-      setSelectedFile(newPath);
-      setIsNewFile(!filePath);
+      // Consider empty string as null
+      const effectiveFilePath = filePath === '' ? null : filePath;
 
-      if (filePath) {
-        await saveLastOpenedFile(filePath);
+      if (effectiveFilePath) {
+        setSelectedFile(effectiveFilePath);
+        setIsNewFile(false);
+
+        try {
+          // Try to save the last opened file
+          await saveLastOpenedFile(effectiveFilePath);
+        } catch (err) {
+          // Silently handle the error so state still updates
+          console.error('Failed to save last opened file:', err);
+        }
+      } else if (selectedFile === DEFAULT_FILE.path || filePath === null) {
+        setSelectedFile(DEFAULT_FILE.path);
+        setIsNewFile(true);
       }
     },
-    [saveLastOpenedFile]
+    [saveLastOpenedFile, selectedFile]
   );
 
   // Load last opened file when workspace changes
   useEffect(() => {
     const initializeFile = async (): Promise<void> => {
-      setSelectedFile(DEFAULT_FILE.path);
-      setIsNewFile(true);
+      try {
+        setSelectedFile(DEFAULT_FILE.path);
+        setIsNewFile(true);
 
-      const lastFile = await loadLastOpenedFile();
-      if (lastFile) {
-        await handleFileSelect(lastFile);
-      } else {
-        await handleFileSelect(null);
+        const lastFile = await loadLastOpenedFile();
+
+        if (lastFile) {
+          setSelectedFile(lastFile);
+          setIsNewFile(false);
+        }
+      } catch (err) {
+        console.error('Failed to load last opened file:', err);
+        setSelectedFile(DEFAULT_FILE.path);
+        setIsNewFile(true);
       }
     };
 
     if (currentWorkspace) {
       void initializeFile();
+    } else {
+      setSelectedFile(DEFAULT_FILE.path);
+      setIsNewFile(true);
     }
-  }, [currentWorkspace, loadLastOpenedFile, handleFileSelect]);
+  }, [currentWorkspace, loadLastOpenedFile, saveLastOpenedFile]);
 
   return { selectedFile, isNewFile, handleFileSelect };
 };
diff --git a/app/src/hooks/useUserAdmin.ts b/app/src/hooks/useUserAdmin.ts
index 9258eb0..07e5763 100644
--- a/app/src/hooks/useUserAdmin.ts
+++ b/app/src/hooks/useUserAdmin.ts
@@ -5,6 +5,7 @@ import {
   deleteUser as adminDeleteUser,
 } from '../api/admin';
 import { notifications } from '@mantine/notifications';
+import { useCallback } from 'react';
 import type { User } from '@/types/models';
 import type { CreateUserRequest, UpdateUserRequest } from '@/types/api';
 
@@ -20,73 +21,77 @@ interface UseUserAdminResult {
 export const useUserAdmin = (): UseUserAdminResult => {
   const { data: users, loading, error, reload } = useAdminData('users');
 
-  const handleCreate = async (
-    userData: CreateUserRequest
-  ): Promise<boolean> => {
-    try {
-      await createUser(userData);
-      notifications.show({
-        title: 'Success',
-        message: 'User created successfully',
-        color: 'green',
-      });
-      await reload();
-      return true;
-    } catch (err) {
-      const message = err instanceof Error ? err.message : String(err);
-      notifications.show({
-        title: 'Error',
-        message: `Failed to create user: ${message}`,
-        color: 'red',
-      });
-      return false;
-    }
-  };
+  const handleCreate = useCallback(
+    async (userData: CreateUserRequest): Promise<boolean> => {
+      try {
+        await createUser(userData);
+        notifications.show({
+          title: 'Success',
+          message: 'User created successfully',
+          color: 'green',
+        });
+        await reload();
+        return true;
+      } catch (err) {
+        const message = err instanceof Error ? err.message : String(err);
+        notifications.show({
+          title: 'Error',
+          message: `Failed to create user: ${message}`,
+          color: 'red',
+        });
+        return false;
+      }
+    },
+    [reload]
+  );
 
-  const handleUpdate = async (
-    userId: number,
-    userData: UpdateUserRequest
-  ): Promise<boolean> => {
-    try {
-      await updateUser(userId, userData);
-      notifications.show({
-        title: 'Success',
-        message: 'User updated successfully',
-        color: 'green',
-      });
-      await reload();
-      return true;
-    } catch (err) {
-      const message = err instanceof Error ? err.message : String(err);
-      notifications.show({
-        title: 'Error',
-        message: `Failed to update user: ${message}`,
-        color: 'red',
-      });
-      return false;
-    }
-  };
+  const handleUpdate = useCallback(
+    async (userId: number, userData: UpdateUserRequest): Promise<boolean> => {
+      try {
+        await updateUser(userId, userData);
+        notifications.show({
+          title: 'Success',
+          message: 'User updated successfully',
+          color: 'green',
+        });
+        await reload();
+        return true;
+      } catch (err) {
+        const message = err instanceof Error ? err.message : String(err);
+        notifications.show({
+          title: 'Error',
+          message: `Failed to update user: ${message}`,
+          color: 'red',
+        });
+        return false;
+      }
+    },
+    [reload]
+  );
 
-  const handleDelete = async (userId: number): Promise<boolean> => {
-    try {
-      await adminDeleteUser(userId);
-      notifications.show({
-        title: 'Success',
-        message: 'User deleted successfully',
-        color: 'green',
-      });
-      await reload();
-      return true;
-    } catch (err) {
-      const message = err instanceof Error ? err.message : String(err);
-      notifications.show({
-        title: 'Error',
-        message: `Failed to delete user: ${message}`,
-        color: 'red',
-      });
-      return false;
-    }
-  };
+  const handleDelete = useCallback(
+    async (userId: number): Promise<boolean> => {
+      try {
+        await adminDeleteUser(userId);
+        notifications.show({
+          title: 'Success',
+          message: 'User deleted successfully',
+          color: 'green',
+        });
+        await reload();
+        return true;
+      } catch (err) {
+        const message = err instanceof Error ? err.message : String(err);
+        notifications.show({
+          title: 'Error',
+          message: `Failed to delete user: ${message}`,
+          color: 'red',
+        });
+        return false;
+      }
+    },
+    [reload]
+  );
 
   return {
     users,
diff --git a/app/src/hooks/useWorkspace.test.ts b/app/src/hooks/useWorkspace.test.ts
new file mode 100644
index 0000000..945285f
--- /dev/null
+++ b/app/src/hooks/useWorkspace.test.ts
@@ -0,0 +1,548 @@
+import { describe, it, expect, vi, beforeEach, afterEach } from 'vitest';
+import { renderHook } from '@testing-library/react';
+import { useWorkspace } from './useWorkspace';
+import {
+  Theme,
+  type Workspace,
+  DEFAULT_WORKSPACE_SETTINGS,
+} from '@/types/models';
+import type { MantineColorScheme } from '@mantine/core';
+
+// Mock the constituent hooks
+const mockWorkspaceData = {
+  currentWorkspace: null as Workspace | null,
+  workspaces: [] as Workspace[],
+  settings: DEFAULT_WORKSPACE_SETTINGS,
+  loading: false,
+};
+
+const mockTheme = {
+  colorScheme: 'light' as MantineColorScheme,
+  updateColorScheme: vi.fn(),
+};
+
+const mockWorkspaceOperations = {
+  switchWorkspace: vi.fn(),
+  deleteCurrentWorkspace: vi.fn(),
+  updateSettings: vi.fn(),
+};
+
+vi.mock('../contexts/WorkspaceDataContext', () => ({
+  useWorkspaceData: () => mockWorkspaceData,
+}));
+
+vi.mock('../contexts/ThemeContext', () => ({
+  useTheme: () => mockTheme,
+}));
+
+vi.mock('./useWorkspaceOperations', () => ({
+  useWorkspaceOperations: () => mockWorkspaceOperations,
+}));
+
+// Mock workspace data
+const mockWorkspace: Workspace = {
+  id: 1,
+  userId: 1,
+  name: 'test-workspace',
+  createdAt: '2024-01-01T00:00:00Z',
+  theme: Theme.Light,
+  autoSave: false,
+  showHiddenFiles: false,
+  gitEnabled: false,
+  gitUrl: '',
+  gitUser: '',
+  gitToken: '',
+  gitAutoCommit: false,
+  gitCommitMsgTemplate: '${action} ${filename}',
+  gitCommitName: '',
+  gitCommitEmail: '',
+};
+
+const mockWorkspaces: Workspace[] = [
+  mockWorkspace,
+  {
+    id: 2,
+    userId: 1,
+    name: 'second-workspace',
+    createdAt: '2024-01-02T00:00:00Z',
+    theme: Theme.Dark,
+    autoSave: true,
+    showHiddenFiles: true,
+    gitEnabled: true,
+    gitUrl: 'https://github.com/user/repo.git',
+    gitUser: 'user',
+    gitToken: 'token',
+    gitAutoCommit: true,
+    gitCommitMsgTemplate: 'auto: ${action} ${filename}',
+    gitCommitName: 'Test User',
+    gitCommitEmail: 'test@example.com',
+  },
+];
+
+describe('useWorkspace', () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+    // Reset mock data to defaults
+    mockWorkspaceData.currentWorkspace = null;
+    mockWorkspaceData.workspaces = [];
+    mockWorkspaceData.settings = DEFAULT_WORKSPACE_SETTINGS;
+    mockWorkspaceData.loading = false;
+    mockTheme.colorScheme = 'light';
+  });
+
+  afterEach(() => {
+    vi.restoreAllMocks();
+  });
+
+  describe('initial state', () => {
+    it('returns default values when no workspace is loaded', () => {
+      const { result } = renderHook(() => useWorkspace());
+
+      expect(result.current.currentWorkspace).toBeNull();
+      expect(result.current.workspaces).toEqual([]);
+      expect(result.current.settings).toEqual(DEFAULT_WORKSPACE_SETTINGS);
+      expect(result.current.loading).toBe(false);
+      expect(result.current.colorScheme).toBe('light');
+    });
+
+    it('provides all expected functions', () => {
+      const { result } = renderHook(() => useWorkspace());
+
+      expect(typeof result.current.updateSettings).toBe('function');
+      expect(typeof result.current.updateColorScheme).toBe('function');
+      expect(typeof result.current.switchWorkspace).toBe('function');
+      expect(typeof result.current.deleteCurrentWorkspace).toBe('function');
+    });
+  });
+
+  describe('workspace data integration', () => {
+    it('returns current workspace data', () => {
+      mockWorkspaceData.currentWorkspace = mockWorkspace;
+      mockWorkspaceData.workspaces = mockWorkspaces;
+      mockWorkspaceData.settings = mockWorkspace;
+
+      const { result } = renderHook(() => useWorkspace());
+
+      expect(result.current.currentWorkspace).toEqual(mockWorkspace);
+      expect(result.current.workspaces).toEqual(mockWorkspaces);
+      expect(result.current.settings).toEqual(mockWorkspace);
+    });
+
+    it('returns loading state from workspace data', () => {
+      mockWorkspaceData.loading = true;
+
+      const { result } = renderHook(() => useWorkspace());
+
+      expect(result.current.loading).toBe(true);
+    });
+
+    it('uses default settings when no current workspace', () => {
+      mockWorkspaceData.currentWorkspace = null;
+      mockWorkspaceData.settings = DEFAULT_WORKSPACE_SETTINGS;
+
+      const { result } = renderHook(() => useWorkspace());
+
+      expect(result.current.settings).toEqual(DEFAULT_WORKSPACE_SETTINGS);
+    });
+
+    it('uses current workspace as settings when available', () => {
+      mockWorkspaceData.currentWorkspace = mockWorkspace;
+      mockWorkspaceData.settings = mockWorkspace;
+
+      const { result } = renderHook(() => useWorkspace());
+
+      expect(result.current.settings).toEqual(mockWorkspace);
+    });
+  });
+
+  describe('theme integration', () => {
+    it('returns color scheme from theme context', () => {
+      mockTheme.colorScheme = 'dark';
+
+      const { result } = renderHook(() => useWorkspace());
+
+      expect(result.current.colorScheme).toBe('dark');
+    });
+
+    it('provides updateColorScheme function from theme context', () => {
+      const { result } = renderHook(() => useWorkspace());
+
+      expect(result.current.updateColorScheme).toBe(
+        mockTheme.updateColorScheme
+      );
+    });
+
+    it('handles light theme', () => {
+      mockTheme.colorScheme = 'light';
+
+      const { result } = renderHook(() => useWorkspace());
+
+      expect(result.current.colorScheme).toBe('light');
+    });
+
+    it('handles auto theme', () => {
+      mockTheme.colorScheme = 'auto';
+
+      const { result } = renderHook(() => useWorkspace());
+
+      expect(result.current.colorScheme).toBe('auto');
+    });
+  });
+
+  describe('workspace operations integration', () => {
+    it('provides switchWorkspace function from operations', () => {
+      const { result } = renderHook(() => useWorkspace());
+
+      expect(result.current.switchWorkspace).toBe(
+        mockWorkspaceOperations.switchWorkspace
+      );
+    });
+
+    it('provides deleteCurrentWorkspace function from operations', () => {
+      const { result } = renderHook(() => useWorkspace());
+
+      expect(result.current.deleteCurrentWorkspace).toBe(
+        mockWorkspaceOperations.deleteCurrentWorkspace
+      );
+    });
+
+    it('provides updateSettings function from operations', () => {
+      const { result } = renderHook(() => useWorkspace());
+
+      expect(result.current.updateSettings).toBe(
+        mockWorkspaceOperations.updateSettings
+      );
+    });
+  });
+
+  describe('data consistency', () => {
+    it('returns consistent data across multiple renders', () => {
+      mockWorkspaceData.currentWorkspace = mockWorkspace;
+      mockWorkspaceData.workspaces = mockWorkspaces;
+      mockWorkspaceData.settings = mockWorkspace;
+      mockTheme.colorScheme = 'dark';
+
+      const { result, rerender } = renderHook(() => useWorkspace());
+
+      const firstResult = { ...result.current };
+
+      rerender();
+
+      expect(result.current.currentWorkspace).toEqual(
+        firstResult.currentWorkspace
+      );
+      expect(result.current.workspaces).toEqual(firstResult.workspaces);
+      expect(result.current.settings).toEqual(firstResult.settings);
+      expect(result.current.colorScheme).toEqual(firstResult.colorScheme);
+    });
+
+    it('reflects changes in underlying data', () => {
+      const { result, rerender } = renderHook(() => useWorkspace());
+
+      // Initially no workspace
+      expect(result.current.currentWorkspace).toBeNull();
+      expect(result.current.workspaces).toEqual([]);
+
+      // Add workspace data
+      mockWorkspaceData.currentWorkspace = mockWorkspace;
+      mockWorkspaceData.workspaces = mockWorkspaces;
+      mockWorkspaceData.settings = mockWorkspace;
+
+      rerender();
+
+      expect(result.current.currentWorkspace).toEqual(mockWorkspace);
+      expect(result.current.workspaces).toEqual(mockWorkspaces);
+      expect(result.current.settings).toEqual(mockWorkspace);
+    });
+
+    it('reflects theme changes', () => {
+      const { result, rerender } = renderHook(() => useWorkspace());
+
+      // Initially light theme
+      expect(result.current.colorScheme).toBe('light');
+
+      // Change to dark theme
+      mockTheme.colorScheme = 'dark';
+
+      rerender();
+
+      expect(result.current.colorScheme).toBe('dark');
+    });
+
+    it('reflects loading state changes', () => {
+      const { result, rerender } = renderHook(() => useWorkspace());
+
+      // Initially not loading
+      expect(result.current.loading).toBe(false);
+
+      // Change to loading
+      mockWorkspaceData.loading = true;
+
+      rerender();
+
+      expect(result.current.loading).toBe(true);
+    });
+  });
+
+  describe('function stability', () => {
+    it('maintains stable function references across re-renders', () => {
+      const { result, rerender } = renderHook(() => useWorkspace());
+
+      const initialFunctions = {
+        updateSettings: result.current.updateSettings,
+        updateColorScheme: result.current.updateColorScheme,
+        switchWorkspace: result.current.switchWorkspace,
+        deleteCurrentWorkspace: result.current.deleteCurrentWorkspace,
+      };
+
+      rerender();
+
+      expect(result.current.updateSettings).toBe(
+        initialFunctions.updateSettings
+      );
+      expect(result.current.updateColorScheme).toBe(
+        initialFunctions.updateColorScheme
+      );
+      expect(result.current.switchWorkspace).toBe(
+        initialFunctions.switchWorkspace
+      );
+      expect(result.current.deleteCurrentWorkspace).toBe(
+        initialFunctions.deleteCurrentWorkspace
+      );
+    });
+
+    it('maintains stable function references when data changes', () => {
+      const { result, rerender } = renderHook(() => useWorkspace());
+
+      const initialFunctions = {
+        updateSettings: result.current.updateSettings,
+        updateColorScheme: result.current.updateColorScheme,
+        switchWorkspace: result.current.switchWorkspace,
+        deleteCurrentWorkspace: result.current.deleteCurrentWorkspace,
+      };
+
+      // Change data
+      mockWorkspaceData.currentWorkspace = mockWorkspace;
+      mockWorkspaceData.workspaces = mockWorkspaces;
+      mockTheme.colorScheme = 'dark';
+
+      rerender();
+
+      expect(result.current.updateSettings).toBe(
+        initialFunctions.updateSettings
+      );
+      expect(result.current.updateColorScheme).toBe(
+        initialFunctions.updateColorScheme
+      );
+      expect(result.current.switchWorkspace).toBe(
+        initialFunctions.switchWorkspace
+      );
+      expect(result.current.deleteCurrentWorkspace).toBe(
+        initialFunctions.deleteCurrentWorkspace
+      );
+    });
+  });
+
+  describe('hook interface', () => {
+    it('returns correct interface structure', () => {
+      const { result } = renderHook(() => useWorkspace());
+
+      const expectedKeys = [
+        'currentWorkspace',
+        'workspaces',
+        'settings',
+        'updateSettings',
+        'loading',
+        'colorScheme',
+        'updateColorScheme',
+        'switchWorkspace',
+        'deleteCurrentWorkspace',
+      ];
+
+      expectedKeys.forEach((key) => {
+        expect(key in result.current).toBe(true);
+      });
+    });
+
+    it('returns correct types for all properties', () => {
+      const { result } = renderHook(() => useWorkspace());
+
+      expect(
+        result.current.currentWorkspace === null ||
+          typeof result.current.currentWorkspace === 'object'
+      ).toBe(true);
+      expect(Array.isArray(result.current.workspaces)).toBe(true);
+      expect(typeof result.current.settings === 'object').toBe(true);
+      expect(typeof result.current.updateSettings === 'function').toBe(true);
+      expect(typeof result.current.loading === 'boolean').toBe(true);
+      expect(typeof result.current.colorScheme === 'string').toBe(true);
+      expect(typeof result.current.updateColorScheme === 'function').toBe(true);
+      expect(typeof result.current.switchWorkspace === 'function').toBe(true);
+      expect(typeof result.current.deleteCurrentWorkspace === 'function').toBe(
+        true
+      );
+    });
+  });
+
+  describe('edge cases', () => {
+    it('handles undefined workspace data gracefully', () => {
+      // Simulate undefined data that might occur during loading
+      mockWorkspaceData.currentWorkspace = null;
+      mockWorkspaceData.workspaces = [];
+      mockWorkspaceData.settings = DEFAULT_WORKSPACE_SETTINGS;
+
+      const { result } = renderHook(() => useWorkspace());
+
+      expect(result.current.currentWorkspace).toBeNull();
+      expect(result.current.workspaces).toEqual([]);
+      expect(result.current.settings).toEqual(DEFAULT_WORKSPACE_SETTINGS);
+      expect(typeof result.current.updateSettings).toBe('function');
+    });
+
+    it('handles empty workspaces array', () => {
+      mockWorkspaceData.workspaces = [];
+
+      const { result } = renderHook(() => useWorkspace());
+
+      expect(result.current.workspaces).toEqual([]);
+    });
+
+    it('handles single workspace', () => {
+      const singleWorkspace = [mockWorkspace];
+      mockWorkspaceData.workspaces = singleWorkspace;
+      mockWorkspaceData.currentWorkspace = mockWorkspace;
+      mockWorkspaceData.settings = mockWorkspace;
+
+      const { result } = renderHook(() => useWorkspace());
+
+      expect(result.current.workspaces).toEqual(singleWorkspace);
+      expect(result.current.currentWorkspace).toEqual(mockWorkspace);
+    });
+
+    it('handles workspace with minimal data', () => {
+      const minimalWorkspace: Workspace = {
+        name: 'minimal',
+        createdAt: Date.now(),
+        ...DEFAULT_WORKSPACE_SETTINGS,
+      };
+
+      mockWorkspaceData.currentWorkspace = minimalWorkspace;
+      mockWorkspaceData.settings = minimalWorkspace;
+
+      const { result } = renderHook(() => useWorkspace());
+
+      expect(result.current.currentWorkspace).toEqual(minimalWorkspace);
+      expect(result.current.settings).toEqual(minimalWorkspace);
+    });
+  });
+
+  describe('integration scenarios', () => {
+    it('provides complete workspace management interface', () => {
+      mockWorkspaceData.currentWorkspace = mockWorkspace;
+      mockWorkspaceData.workspaces = mockWorkspaces;
+      mockWorkspaceData.settings = mockWorkspace;
+      mockTheme.colorScheme = 'light';
+
+      const { result } = renderHook(() => useWorkspace());
+
+      // Should have all data
+      expect(result.current.currentWorkspace).toEqual(mockWorkspace);
+      expect(result.current.workspaces).toEqual(mockWorkspaces);
+      expect(result.current.settings).toEqual(mockWorkspace);
+      expect(result.current.colorScheme).toBe('light');
+
+      // Should have all operations
+      expect(typeof result.current.updateSettings).toBe('function');
+      expect(typeof result.current.switchWorkspace).toBe('function');
+      expect(typeof result.current.deleteCurrentWorkspace).toBe('function');
+      expect(typeof result.current.updateColorScheme).toBe('function');
+    });
+
+    it('supports workspace switching workflow', () => {
+      const { result } = renderHook(() => useWorkspace());
+
+      // Initially no workspace
+      expect(result.current.currentWorkspace).toBeNull();
+
+      // Should provide switch function
+      expect(typeof result.current.switchWorkspace).toBe('function');
+      expect(result.current.switchWorkspace).toBe(
+        mockWorkspaceOperations.switchWorkspace
+      );
+    });
+
+    it('supports settings management workflow', () => {
+      mockWorkspaceData.currentWorkspace = mockWorkspace;
+      mockWorkspaceData.settings = mockWorkspace;
+
+      const { result } = renderHook(() => useWorkspace());
+
+      // Should have current settings
+      expect(result.current.settings).toEqual(mockWorkspace);
+
+      // Should provide update function
+      expect(typeof result.current.updateSettings).toBe('function');
+      expect(result.current.updateSettings).toBe(
+        mockWorkspaceOperations.updateSettings
+      );
+    });
+
+    it('supports theme management workflow', () => {
+      mockTheme.colorScheme = 'dark';
+
+      const { result } = renderHook(() => useWorkspace());
+
+      // Should have current color scheme
+      expect(result.current.colorScheme).toBe('dark');
+
+      // Should provide update function
+      expect(typeof result.current.updateColorScheme).toBe('function');
+      expect(result.current.updateColorScheme).toBe(
+        mockTheme.updateColorScheme
+      );
+    });
+  });
+
+  describe('mock integration validation', () => {
+    it('correctly integrates with WorkspaceDataContext mock', () => {
+      mockWorkspaceData.currentWorkspace = mockWorkspace;
+      mockWorkspaceData.workspaces = mockWorkspaces;
+      mockWorkspaceData.settings = mockWorkspace;
+      mockWorkspaceData.loading = true;
+
+      const { result } = renderHook(() => useWorkspace());
+
+      expect(result.current.currentWorkspace).toBe(
+        mockWorkspaceData.currentWorkspace
+      );
+      expect(result.current.workspaces).toBe(mockWorkspaceData.workspaces);
+      expect(result.current.settings).toBe(mockWorkspaceData.settings);
+      expect(result.current.loading).toBe(mockWorkspaceData.loading);
+    });
+
+    it('correctly integrates with ThemeContext mock', () => {
+      mockTheme.colorScheme = 'dark';
+
+      const { result } = renderHook(() => useWorkspace());
+
+      expect(result.current.colorScheme).toBe(mockTheme.colorScheme);
+      expect(result.current.updateColorScheme).toBe(
+        mockTheme.updateColorScheme
+      );
+    });
+
+    it('correctly integrates with useWorkspaceOperations mock', () => {
+      const { result } = renderHook(() => useWorkspace());
+
+      expect(result.current.switchWorkspace).toBe(
+        mockWorkspaceOperations.switchWorkspace
+      );
+      expect(result.current.deleteCurrentWorkspace).toBe(
+        mockWorkspaceOperations.deleteCurrentWorkspace
+      );
+      expect(result.current.updateSettings).toBe(
+        mockWorkspaceOperations.updateSettings
+      );
+    });
+  });
+});