fix: deduplicate and focus code on projects

src/main/engine/ProjectEngine.ts

@@ -23,6 +23,25 @@ export class ProjectEngine extends EventEmitter {
     super();
   }
 
+  private assertDeletableProject(id: string): void {
+    if (id === 'default') {
+      throw new Error('Cannot delete the default project');
+    }
+  }
+
+  private mapDbProjectToProjectData(dbProject: Project): ProjectData {
+    return {
+      id: dbProject.id,
+      name: dbProject.name,
+      slug: dbProject.slug,
+      description: dbProject.description || undefined,
+      dataPath: dbProject.dataPath || undefined,
+      createdAt: dbProject.createdAt,
+      updatedAt: dbProject.updatedAt,
+      isActive: dbProject.isActive ?? false,
+    };
+  }
+
   private generateSlug(name: string): string {
     return name
       .toLowerCase()
@@ -160,10 +179,7 @@ export class ProjectEngine extends EventEmitter {
   }
 
   async deleteProject(id: string): Promise<boolean> {
-    // Prevent deleting the default project
-    if (id === 'default') {
-      throw new Error('Cannot delete the default project');
-    }
+    this.assertDeletableProject(id);
 
     const db = getDatabase().getLocal();
     const existing = await db.select().from(projects).where(eq(projects.id, id)).get();
@@ -182,10 +198,7 @@ export class ProjectEngine extends EventEmitter {
   }
 
   async deleteProjectWithData(id: string): Promise<boolean> {
-    // Prevent deleting the default project
-    if (id === 'default') {
-      throw new Error('Cannot delete the default project');
-    }
+    this.assertDeletableProject(id);
 
     const db = getDatabase().getLocal();
     const existing = await db.select().from(projects).where(eq(projects.id, id)).get();
@@ -224,32 +237,14 @@ export class ProjectEngine extends EventEmitter {
       return null;
     }
 
-    return {
-      id: dbProject.id,
-      name: dbProject.name,
-      slug: dbProject.slug,
-      description: dbProject.description || undefined,
-      dataPath: dbProject.dataPath || undefined,
-      createdAt: dbProject.createdAt,
-      updatedAt: dbProject.updatedAt,
-      isActive: dbProject.isActive ?? false,
-    };
+    return this.mapDbProjectToProjectData(dbProject);
   }
 
   async getAllProjects(): Promise<ProjectData[]> {
     const db = getDatabase().getLocal();
     const dbProjects = await db.select().from(projects).all();
 
-    return dbProjects.map(p => ({
-      id: p.id,
-      name: p.name,
-      slug: p.slug,
-      description: p.description || undefined,
-      dataPath: p.dataPath || undefined,
-      createdAt: p.createdAt,
-      updatedAt: p.updatedAt,
-      isActive: p.isActive ?? false,
-    }));
+    return dbProjects.map(p => this.mapDbProjectToProjectData(p));
   }
 
   async getActiveProject(): Promise<ProjectData | null> {
@@ -261,16 +256,7 @@ export class ProjectEngine extends EventEmitter {
       return this.getProject('default');
     }
 
-    return {
-      id: dbProject.id,
-      name: dbProject.name,
-      slug: dbProject.slug,
-      description: dbProject.description || undefined,
-      dataPath: dbProject.dataPath || undefined,
-      createdAt: dbProject.createdAt,
-      updatedAt: dbProject.updatedAt,
-      isActive: dbProject.isActive ?? false,
-    };
+    return this.mapDbProjectToProjectData(dbProject);
   }
 
   async setActiveProject(id: string): Promise<ProjectData | null> {

tests/engine/ProjectEngine.test.ts

@@ -215,6 +215,15 @@ describe('ProjectEngine', () => {
       );
     });
 
+    it('should short-circuit before database access when deleting default project', async () => {
+      await expect(projectEngine.deleteProject('default')).rejects.toThrow(
+        'Cannot delete the default project'
+      );
+
+      expect(mockLocalDb.select).not.toHaveBeenCalled();
+      expect(mockLocalDb.delete).not.toHaveBeenCalled();
+    });
+
     it('should return false for non-existent project', async () => {
       const result = await projectEngine.deleteProject('non-existent-id');
       expect(result).toBe(false);
@@ -260,6 +269,15 @@ describe('ProjectEngine', () => {
       );
     });
 
+    it('should short-circuit before database access when deleting default project', async () => {
+      await expect(projectEngine.deleteProjectWithData('default')).rejects.toThrow(
+        'Cannot delete the default project'
+      );
+
+      expect(mockLocalDb.select).not.toHaveBeenCalled();
+      expect(mockLocalDb.delete).not.toHaveBeenCalled();
+    });
+
     it('should return false for non-existent project', async () => {
       const result = await projectEngine.deleteProjectWithData('non-existent-id');
       expect(result).toBe(false);
@@ -990,6 +1008,35 @@ describe('ProjectEngine', () => {
       expect(result?.id).toBe('active-project');
       expect(result?.isActive).toBe(true);
     });
+
+    it('should normalize nullable fields in active project mapping', async () => {
+      const activeProject = {
+        id: 'active-nullable',
+        name: 'Active Nullable',
+        slug: 'active-nullable',
+        description: null,
+        dataPath: null,
+        createdAt: new Date(),
+        updatedAt: new Date(),
+        isActive: null,
+      };
+
+      vi.mocked(mockLocalDb.select).mockImplementation(() => {
+        const chain = createSelectChain();
+        chain.where = vi.fn().mockReturnValue({
+          ...chain,
+          get: vi.fn().mockResolvedValue(activeProject),
+        });
+        return chain;
+      });
+
+      const result = await projectEngine.getActiveProject();
+
+      expect(result).not.toBeNull();
+      expect(result?.description).toBeUndefined();
+      expect(result?.dataPath).toBeUndefined();
+      expect(result?.isActive).toBe(false);
+    });
   });
 
   describe('setActiveProject', () => {