diff --git a/apps/web/modules/survey/editor/lib/survey.test.ts b/apps/web/modules/survey/editor/lib/survey.test.ts
new file mode 100644
index 0000000000..0b554409c9
--- /dev/null
+++ b/apps/web/modules/survey/editor/lib/survey.test.ts
@@ -0,0 +1,755 @@
+import { surveyCache } from "@/lib/survey/cache";
+import { getActionClasses } from "@/modules/survey/lib/action-class";
+import { getOrganizationAIKeys, getOrganizationIdFromEnvironmentId } from "@/modules/survey/lib/organization";
+import { getSurvey } from "@/modules/survey/lib/survey";
+import { ActionClass, Prisma } from "@prisma/client";
+import { afterEach, beforeEach, describe, expect, test, vi } from "vitest";
+import { prisma } from "@formbricks/database";
+import { DatabaseError, InvalidInputError, ResourceNotFoundError } from "@formbricks/types/errors";
+import { TSegment } from "@formbricks/types/segment";
+import { TSurvey, TSurveyQuestionTypeEnum } from "@formbricks/types/surveys/types";
+import { checkTriggersValidity, handleTriggerUpdates, updateSurvey } from "./survey";
+
+// Mock dependencies
+vi.mock("@formbricks/database", () => ({
+  prisma: {
+    survey: {
+      update: vi.fn(),
+    },
+    segment: {
+      update: vi.fn(),
+      delete: vi.fn(),
+    },
+  },
+}));
+
+vi.mock("@/lib/cache/segment", () => ({
+  segmentCache: {
+    revalidate: vi.fn(),
+  },
+}));
+
+vi.mock("@/lib/survey/cache", () => ({
+  surveyCache: {
+    revalidate: vi.fn(),
+  },
+}));
+
+vi.mock("@/lib/survey/utils", () => ({
+  checkForInvalidImagesInQuestions: vi.fn(),
+}));
+
+vi.mock("@/modules/survey/lib/action-class", () => ({
+  getActionClasses: vi.fn(),
+}));
+
+vi.mock("@/modules/survey/lib/organization", () => ({
+  getOrganizationIdFromEnvironmentId: vi.fn(),
+  getOrganizationAIKeys: vi.fn(),
+}));
+
+vi.mock("@/modules/survey/lib/survey", () => ({
+  getSurvey: vi.fn(),
+  selectSurvey: {
+    id: true,
+    createdAt: true,
+    updatedAt: true,
+    name: true,
+    type: true,
+    environmentId: true,
+  },
+}));
+
+vi.mock("@formbricks/logger", () => ({
+  logger: {
+    error: vi.fn(),
+  },
+}));
+
+describe("Survey Editor Library Tests", () => {
+  afterEach(() => {
+    vi.clearAllMocks();
+  });
+
+  describe("updateSurvey", () => {
+    const mockSurvey = {
+      id: "survey123",
+      createdAt: new Date(),
+      updatedAt: new Date(),
+      name: "Test Survey",
+      type: "app",
+      environmentId: "env123",
+      createdBy: "user123",
+      status: "draft",
+      displayOption: "displayOnce",
+      questions: [
+        {
+          id: "q1",
+          type: TSurveyQuestionTypeEnum.OpenText,
+          headline: { default: "Question 1" },
+          required: false,
+          inputType: "text",
+          charLimit: { enabled: false },
+        },
+      ],
+      welcomeCard: {
+        enabled: false,
+        timeToFinish: true,
+        showResponseCount: false,
+      },
+      triggers: [],
+      endings: [],
+      hiddenFields: { enabled: false },
+      delay: 0,
+      autoComplete: null,
+      closeOnDate: null,
+      runOnDate: null,
+      projectOverwrites: null,
+      styling: null,
+      showLanguageSwitch: false,
+      segment: null,
+      surveyClosedMessage: null,
+      singleUse: null,
+      isVerifyEmailEnabled: false,
+      recaptcha: null,
+      isSingleResponsePerEmailEnabled: false,
+      isBackButtonHidden: false,
+      pin: null,
+      resultShareKey: null,
+      displayPercentage: null,
+      languages: [
+        {
+          language: {
+            id: "en",
+            code: "en",
+            createdAt: new Date(),
+            updatedAt: new Date(),
+            alias: null,
+            projectId: "project1",
+          },
+          default: true,
+          enabled: true,
+        },
+      ],
+      variables: [],
+      followUps: [],
+    } as unknown as TSurvey;
+
+    const mockCurrentSurvey = { ...mockSurvey };
+    const mockActionClasses: ActionClass[] = [
+      {
+        id: "action1",
+        name: "Code Action",
+        description: "Action from code",
+        type: "code" as const,
+        environmentId: "env123",
+        createdAt: new Date(),
+        updatedAt: new Date(),
+        key: null,
+        noCodeConfig: null,
+      },
+    ];
+
+    const mockOrganizationId = "org123";
+    const mockOrganization = {
+      id: mockOrganizationId,
+      name: "Test Organization",
+      ownerUserId: "user123",
+      billing: {
+        stripeCustomerId: "cust_123",
+        plan: "free" as const,
+        features: {},
+        period: "monthly" as const,
+        periodStart: new Date(),
+      },
+      isAIEnabled: false,
+    };
+
+    beforeEach(() => {
+      vi.mocked(prisma.survey.update).mockResolvedValue(mockSurvey as any);
+      vi.mocked(prisma.segment.update).mockResolvedValue({
+        id: "segment1",
+        environmentId: "env123",
+        surveys: [{ id: "survey123" }],
+      } as any);
+
+      vi.mocked(getSurvey).mockResolvedValue(mockCurrentSurvey);
+      vi.mocked(getActionClasses).mockResolvedValue(mockActionClasses);
+      vi.mocked(getOrganizationIdFromEnvironmentId).mockResolvedValue(mockOrganizationId);
+      vi.mocked(getOrganizationAIKeys).mockResolvedValue(mockOrganization as any);
+    });
+
+    test("should handle languages update", async () => {
+      const updatedSurvey: TSurvey = {
+        ...mockSurvey,
+        languages: [
+          {
+            language: {
+              id: "en",
+              code: "en",
+              createdAt: new Date(),
+              updatedAt: new Date(),
+              alias: null,
+              projectId: "project1",
+            },
+            default: true,
+            enabled: true,
+          },
+          {
+            language: {
+              id: "es",
+              code: "es",
+              createdAt: new Date(),
+              updatedAt: new Date(),
+              alias: null,
+              projectId: "project1",
+            },
+            default: false,
+            enabled: true,
+          },
+        ],
+      };
+
+      await updateSurvey(updatedSurvey);
+
+      expect(prisma.survey.update).toHaveBeenCalledWith({
+        where: { id: "survey123" },
+        data: expect.objectContaining({
+          languages: {
+            updateMany: expect.any(Array),
+            create: expect.arrayContaining([
+              expect.objectContaining({
+                languageId: "es",
+                default: false,
+                enabled: true,
+              }),
+            ]),
+          },
+        }),
+        select: expect.any(Object),
+      });
+    });
+
+    test("should delete private segment for non-app type surveys", async () => {
+      const mockSegment: TSegment = {
+        id: "segment1",
+        title: "Test Segment",
+        isPrivate: true,
+        environmentId: "env123",
+        surveys: ["survey123"],
+        createdAt: new Date(),
+        updatedAt: new Date(),
+        description: null,
+        filters: [{ id: "filter1" } as any],
+      };
+
+      const updatedSurvey: TSurvey = {
+        ...mockSurvey,
+        type: "link",
+        segment: mockSegment,
+      };
+
+      await updateSurvey(updatedSurvey);
+
+      expect(prisma.segment.update).toHaveBeenCalledWith({
+        where: { id: "segment1" },
+        data: {
+          surveys: {
+            disconnect: {
+              id: "survey123",
+            },
+          },
+        },
+      });
+      expect(prisma.segment.delete).toHaveBeenCalledWith({
+        where: {
+          id: "segment1",
+        },
+      });
+    });
+
+    test("should disconnect public segment for non-app type surveys", async () => {
+      const mockSegment: TSegment = {
+        id: "segment1",
+        title: "Test Segment",
+        isPrivate: false,
+        environmentId: "env123",
+        surveys: ["survey123"],
+        createdAt: new Date(),
+        updatedAt: new Date(),
+        description: null,
+        filters: [],
+      };
+
+      const updatedSurvey: TSurvey = {
+        ...mockSurvey,
+        type: "link",
+        segment: mockSegment,
+      };
+
+      await updateSurvey(updatedSurvey);
+
+      expect(prisma.survey.update).toHaveBeenCalledWith({
+        where: {
+          id: "survey123",
+        },
+        data: {
+          segment: {
+            disconnect: true,
+          },
+        },
+      });
+    });
+
+    test("should handle followUps updates", async () => {
+      const updatedSurvey: TSurvey = {
+        ...mockSurvey,
+        followUps: [
+          {
+            id: "f1",
+            name: "Existing Follow Up",
+            createdAt: new Date(),
+            updatedAt: new Date(),
+            surveyId: "survey123",
+            trigger: {
+              type: "response",
+              properties: {
+                endingIds: ["ending1"],
+              },
+            },
+            action: {
+              type: "send-email",
+              properties: {
+                to: "test@example.com",
+                subject: "Test",
+                body: "Test body",
+                from: "test@formbricks.com",
+                replyTo: ["reply@formbricks.com"],
+                attachResponseData: false,
+              },
+            },
+            deleted: false,
+          },
+          {
+            id: "f2",
+            name: "New Follow Up",
+            createdAt: new Date(),
+            updatedAt: new Date(),
+            surveyId: "survey123",
+            trigger: {
+              type: "response",
+              properties: {
+                endingIds: ["ending1"],
+              },
+            },
+            action: {
+              type: "send-email",
+              properties: {
+                to: "new@example.com",
+                subject: "New Test",
+                body: "New test body",
+                from: "test@formbricks.com",
+                replyTo: ["reply@formbricks.com"],
+                attachResponseData: false,
+              },
+            },
+            deleted: false,
+          },
+          {
+            id: "f3",
+            name: "Follow Up To Delete",
+            createdAt: new Date(),
+            updatedAt: new Date(),
+            surveyId: "survey123",
+            trigger: {
+              type: "response",
+              properties: {
+                endingIds: ["ending1"],
+              },
+            },
+            action: {
+              type: "send-email",
+              properties: {
+                to: "delete@example.com",
+                subject: "Delete Test",
+                body: "Delete test body",
+                from: "test@formbricks.com",
+                replyTo: ["reply@formbricks.com"],
+                attachResponseData: false,
+              },
+            },
+            deleted: true,
+          },
+        ],
+      };
+
+      // Mock current survey with existing followUps
+      vi.mocked(getSurvey).mockResolvedValueOnce({
+        ...mockCurrentSurvey,
+        followUps: [
+          {
+            id: "f1",
+            name: "Existing Follow Up",
+            trigger: {
+              type: "response",
+              properties: {
+                endingIds: ["ending1"],
+              },
+            },
+            action: {
+              type: "send-email",
+              properties: {
+                to: "test@example.com",
+                subject: "Test",
+                body: "Test body",
+                from: "test@formbricks.com",
+                replyTo: ["reply@formbricks.com"],
+                attachResponseData: false,
+              },
+            },
+          },
+        ],
+      } as any);
+
+      await updateSurvey(updatedSurvey);
+
+      expect(prisma.survey.update).toHaveBeenCalledWith({
+        where: { id: "survey123" },
+        data: expect.objectContaining({
+          followUps: {
+            updateMany: [
+              {
+                where: {
+                  id: "f1",
+                },
+                data: expect.objectContaining({
+                  name: "Existing Follow Up",
+                }),
+              },
+            ],
+            createMany: {
+              data: [
+                expect.objectContaining({
+                  name: "New Follow Up",
+                }),
+              ],
+            },
+            deleteMany: [
+              {
+                id: "f3",
+              },
+            ],
+          },
+        }),
+        select: expect.any(Object),
+      });
+    });
+
+    test("should handle scheduled status based on runOnDate", async () => {
+      const tomorrow = new Date();
+      tomorrow.setDate(tomorrow.getDate() + 1);
+
+      const updatedSurvey: TSurvey = {
+        ...mockSurvey,
+        status: "completed",
+        runOnDate: tomorrow,
+      };
+
+      await updateSurvey(updatedSurvey);
+
+      expect(prisma.survey.update).toHaveBeenCalledWith({
+        where: { id: "survey123" },
+        data: expect.objectContaining({
+          status: "scheduled", // Should be changed to scheduled because runOnDate is in the future
+        }),
+        select: expect.any(Object),
+      });
+    });
+
+    test("should remove scheduled status when runOnDate is not set", async () => {
+      const updatedSurvey: TSurvey = {
+        ...mockSurvey,
+        status: "scheduled",
+        runOnDate: null,
+      };
+
+      await updateSurvey(updatedSurvey);
+
+      expect(prisma.survey.update).toHaveBeenCalledWith({
+        where: { id: "survey123" },
+        data: expect.objectContaining({
+          status: "inProgress", // Should be changed to inProgress because runOnDate is null
+        }),
+        select: expect.any(Object),
+      });
+    });
+
+    test("should throw ResourceNotFoundError when survey is not found", async () => {
+      vi.mocked(getSurvey).mockResolvedValueOnce(null as unknown as TSurvey);
+
+      await expect(updateSurvey(mockSurvey)).rejects.toThrow(ResourceNotFoundError);
+      expect(getSurvey).toHaveBeenCalledWith("survey123");
+    });
+
+    test("should throw ResourceNotFoundError when organization is not found", async () => {
+      vi.mocked(getOrganizationAIKeys).mockResolvedValueOnce(null);
+
+      await expect(updateSurvey(mockSurvey)).rejects.toThrow(ResourceNotFoundError);
+    });
+
+    test("should throw DatabaseError when Prisma throws a known request error", async () => {
+      const prismaError = new Prisma.PrismaClientKnownRequestError("Database error", {
+        code: "P2002",
+        clientVersion: "4.0.0",
+      });
+      vi.mocked(prisma.survey.update).mockRejectedValueOnce(prismaError);
+
+      await expect(updateSurvey(mockSurvey)).rejects.toThrow(DatabaseError);
+    });
+
+    test("should rethrow other errors", async () => {
+      const genericError = new Error("Some other error");
+      vi.mocked(prisma.survey.update).mockRejectedValueOnce(genericError);
+
+      await expect(updateSurvey(mockSurvey)).rejects.toThrow(genericError);
+    });
+
+    test("should throw InvalidInputError for invalid segment filters", async () => {
+      const updatedSurvey: TSurvey = {
+        ...mockSurvey,
+        segment: {
+          id: "segment1",
+          title: "Test Segment",
+          isPrivate: false,
+          environmentId: "env123",
+          surveys: ["survey123"],
+          createdAt: new Date(),
+          updatedAt: new Date(),
+          description: null,
+          filters: "invalid filters" as any,
+        },
+      };
+
+      await expect(updateSurvey(updatedSurvey)).rejects.toThrow(InvalidInputError);
+    });
+
+    test("should handle error in segment update", async () => {
+      vi.mocked(prisma.segment.update).mockRejectedValueOnce(new Error("Error updating survey"));
+
+      const updatedSurvey: TSurvey = {
+        ...mockSurvey,
+        segment: {
+          id: "segment1",
+          title: "Test Segment",
+          isPrivate: false,
+          environmentId: "env123",
+          surveys: ["survey123"],
+          createdAt: new Date(),
+          updatedAt: new Date(),
+          description: null,
+          filters: [],
+        },
+      };
+
+      await expect(updateSurvey(updatedSurvey)).rejects.toThrow("Error updating survey");
+    });
+  });
+
+  describe("checkTriggersValidity", () => {
+    const mockActionClasses: ActionClass[] = [
+      {
+        id: "action1",
+        name: "Action 1",
+        description: "Test Action 1",
+        type: "code" as const,
+        environmentId: "env123",
+        createdAt: new Date(),
+        updatedAt: new Date(),
+        key: null,
+        noCodeConfig: null,
+      },
+      {
+        id: "action2",
+        name: "Action 2",
+        description: "Test Action 2",
+        type: "noCode" as const,
+        environmentId: "env123",
+        createdAt: new Date(),
+        updatedAt: new Date(),
+        key: null,
+        noCodeConfig: null,
+      },
+    ];
+
+    const createFullActionClass = (id: string, type: "code" | "noCode" = "code"): ActionClass => ({
+      id,
+      name: `Action ${id}`,
+      description: `Test Action ${id}`,
+      type,
+      environmentId: "env123",
+      createdAt: new Date(),
+      updatedAt: new Date(),
+      key: null,
+      noCodeConfig: null,
+    });
+
+    test("should not throw error for valid triggers", () => {
+      const triggers = [
+        { actionClass: createFullActionClass("action1") },
+        { actionClass: createFullActionClass("action2", "noCode") },
+      ];
+
+      expect(() => checkTriggersValidity(triggers as any, mockActionClasses)).not.toThrow();
+    });
+
+    test("should throw error for invalid trigger id", () => {
+      const triggers = [
+        { actionClass: createFullActionClass("action1") },
+        { actionClass: createFullActionClass("invalid") },
+      ];
+
+      expect(() => checkTriggersValidity(triggers as any, mockActionClasses)).toThrow(InvalidInputError);
+      expect(() => checkTriggersValidity(triggers as any, mockActionClasses)).toThrow("Invalid trigger id");
+    });
+
+    test("should throw error for duplicate trigger ids", () => {
+      const triggers = [
+        { actionClass: createFullActionClass("action1") },
+        { actionClass: createFullActionClass("action1") },
+      ];
+
+      expect(() => checkTriggersValidity(triggers as any, mockActionClasses)).toThrow(InvalidInputError);
+      expect(() => checkTriggersValidity(triggers as any, mockActionClasses)).toThrow("Duplicate trigger id");
+    });
+
+    test("should do nothing when triggers are undefined", () => {
+      expect(() => checkTriggersValidity(undefined as any, mockActionClasses)).not.toThrow();
+    });
+  });
+
+  describe("handleTriggerUpdates", () => {
+    const mockActionClasses: ActionClass[] = [
+      {
+        id: "action1",
+        name: "Action 1",
+        description: "Test Action 1",
+        type: "code" as const,
+        environmentId: "env123",
+        createdAt: new Date(),
+        updatedAt: new Date(),
+        key: null,
+        noCodeConfig: null,
+      },
+      {
+        id: "action2",
+        name: "Action 2",
+        description: "Test Action 2",
+        type: "noCode" as const,
+        environmentId: "env123",
+        createdAt: new Date(),
+        updatedAt: new Date(),
+        key: null,
+        noCodeConfig: null,
+      },
+      {
+        id: "action3",
+        name: "Action 3",
+        description: "Test Action 3",
+        type: "noCode" as const,
+        environmentId: "env123",
+        createdAt: new Date(),
+        updatedAt: new Date(),
+        key: null,
+        noCodeConfig: null,
+      },
+    ];
+
+    const createActionClassObj = (id: string, type: "code" | "noCode" = "code"): ActionClass => ({
+      id,
+      name: `Action ${id}`,
+      description: `Test Action ${id}`,
+      type,
+      environmentId: "env123",
+      createdAt: new Date(),
+      updatedAt: new Date(),
+      key: null,
+      noCodeConfig: null,
+    });
+
+    test("should return empty object when updatedTriggers is undefined", () => {
+      const result = handleTriggerUpdates(undefined as any, [], mockActionClasses);
+      expect(result).toEqual({});
+    });
+
+    test("should identify added triggers correctly", () => {
+      const currentTriggers = [{ actionClass: createActionClassObj("action1") }];
+      const updatedTriggers = [
+        { actionClass: createActionClassObj("action1") },
+        { actionClass: createActionClassObj("action2", "noCode") },
+      ];
+
+      const result = handleTriggerUpdates(updatedTriggers as any, currentTriggers as any, mockActionClasses);
+
+      expect(result).toEqual({
+        create: [{ actionClassId: "action2" }],
+      });
+      expect(surveyCache.revalidate).toHaveBeenCalledWith({ actionClassId: "action2" });
+    });
+
+    test("should identify deleted triggers correctly", () => {
+      const currentTriggers = [
+        { actionClass: createActionClassObj("action1") },
+        { actionClass: createActionClassObj("action2", "noCode") },
+      ];
+      const updatedTriggers = [{ actionClass: createActionClassObj("action1") }];
+
+      const result = handleTriggerUpdates(updatedTriggers as any, currentTriggers as any, mockActionClasses);
+
+      expect(result).toEqual({
+        deleteMany: {
+          actionClassId: {
+            in: ["action2"],
+          },
+        },
+      });
+      expect(surveyCache.revalidate).toHaveBeenCalledWith({ actionClassId: "action2" });
+    });
+
+    test("should handle both added and deleted triggers", () => {
+      const currentTriggers = [
+        { actionClass: createActionClassObj("action1") },
+        { actionClass: createActionClassObj("action2", "noCode") },
+      ];
+      const updatedTriggers = [
+        { actionClass: createActionClassObj("action1") },
+        { actionClass: createActionClassObj("action3", "noCode") },
+      ];
+
+      const result = handleTriggerUpdates(updatedTriggers as any, currentTriggers as any, mockActionClasses);
+
+      expect(result).toEqual({
+        create: [{ actionClassId: "action3" }],
+        deleteMany: {
+          actionClassId: {
+            in: ["action2"],
+          },
+        },
+      });
+      expect(surveyCache.revalidate).toHaveBeenCalledTimes(2);
+      expect(surveyCache.revalidate).toHaveBeenCalledWith({ actionClassId: "action2" });
+      expect(surveyCache.revalidate).toHaveBeenCalledWith({ actionClassId: "action3" });
+    });
+
+    test("should validate triggers before processing", () => {
+      const currentTriggers = [{ actionClass: createActionClassObj("action1") }];
+      const updatedTriggers = [
+        { actionClass: createActionClassObj("action1") },
+        { actionClass: createActionClassObj("invalid") },
+      ];
+
+      expect(() =>
+        handleTriggerUpdates(updatedTriggers as any, currentTriggers as any, mockActionClasses)
+      ).toThrow(InvalidInputError);
+    });
+  });
+});