bitwarden-browser/apps/browser/src/autofill/services/autofill-overlay-content.service.spec.ts

import { mock } from "jest-mock-extended";

import { AuthenticationStatus } from "@bitwarden/common/auth/enums/authentication-status";

import { EVENTS } from "../constants";
import { createAutofillFieldMock } from "../jest/autofill-mocks";
import { flushPromises } from "../jest/testing-utils";
import AutofillField from "../models/autofill-field";
import { ElementWithOpId, FormFieldElement } from "../types";
import {
  AutofillOverlayElement,
  AutofillOverlayVisibility,
  RedirectFocusDirection,
} from "../utils/autofill-overlay.enum";

import { AutoFillConstants } from "./autofill-constants";
import AutofillOverlayContentService from "./autofill-overlay-content.service";

const defaultWindowReadyState = document.readyState;
const defaultDocumentVisibilityState = document.visibilityState;
describe("AutofillOverlayContentService", () => {
  let autofillOverlayContentService: AutofillOverlayContentService;
  let sendExtensionMessageSpy: jest.SpyInstance;

  beforeEach(() => {
    autofillOverlayContentService = new AutofillOverlayContentService();
    sendExtensionMessageSpy = jest
      .spyOn(autofillOverlayContentService as any, "sendExtensionMessage")
      .mockResolvedValue(undefined);
    Object.defineProperty(document, "readyState", {
      value: defaultWindowReadyState,
      writable: true,
    });
    Object.defineProperty(document, "visibilityState", {
      value: defaultDocumentVisibilityState,
      writable: true,
    });
    Object.defineProperty(document, "activeElement", {
      value: null,
      writable: true,
    });
    Object.defineProperty(window, "innerHeight", {
      value: 1080,
      writable: true,
    });
  });

  afterEach(() => {
    jest.clearAllMocks();
  });

  describe("init", () => {
    let setupGlobalEventListenersSpy: jest.SpyInstance;
    let setupMutationObserverSpy: jest.SpyInstance;

    beforeEach(() => {
      jest.spyOn(document, "addEventListener");
      jest.spyOn(window, "addEventListener");
      setupGlobalEventListenersSpy = jest.spyOn(
        autofillOverlayContentService as any,
        "setupGlobalEventListeners"
      );
      setupMutationObserverSpy = jest.spyOn(
        autofillOverlayContentService as any,
        "setupMutationObserver"
      );
    });

    it("sets up a DOMContentLoaded event listener that triggers setting up the mutation observers", () => {
      Object.defineProperty(document, "readyState", {
        value: "loading",
        writable: true,
      });

      autofillOverlayContentService.init();

      expect(document.addEventListener).toHaveBeenCalledWith(
        "DOMContentLoaded",
        setupGlobalEventListenersSpy
      );
      expect(setupGlobalEventListenersSpy).not.toHaveBeenCalled();
    });

    it("sets up a visibility change listener for the DOM", () => {
      const handleVisibilityChangeEventSpy = jest.spyOn(
        autofillOverlayContentService as any,
        "handleVisibilityChangeEvent"
      );

      autofillOverlayContentService.init();

      expect(document.addEventListener).toHaveBeenCalledWith(
        "visibilitychange",
        handleVisibilityChangeEventSpy
      );
    });

    it("sets up a focus out listener for the window", () => {
      const handleFormFieldBlurEventSpy = jest.spyOn(
        autofillOverlayContentService as any,
        "handleFormFieldBlurEvent"
      );

      autofillOverlayContentService.init();

      expect(window.addEventListener).toHaveBeenCalledWith("focusout", handleFormFieldBlurEventSpy);
    });

    it("sets up mutation observers for the body and html element", () => {
      jest
        .spyOn(globalThis, "MutationObserver")
        .mockImplementation(() => mock<MutationObserver>({ observe: jest.fn() }));
      const handleOverlayElementMutationObserverUpdateSpy = jest.spyOn(
        autofillOverlayContentService as any,
        "handleOverlayElementMutationObserverUpdate"
      );
      const handleBodyElementMutationObserverUpdateSpy = jest.spyOn(
        autofillOverlayContentService as any,
        "handleBodyElementMutationObserverUpdate"
      );
      const handleDocumentElementMutationObserverUpdateSpy = jest.spyOn(
        autofillOverlayContentService as any,
        "handleDocumentElementMutationObserverUpdate"
      );

      autofillOverlayContentService.init();

      expect(setupMutationObserverSpy).toHaveBeenCalledTimes(1);
      expect(globalThis.MutationObserver).toHaveBeenNthCalledWith(
        1,
        handleOverlayElementMutationObserverUpdateSpy
      );
      expect(globalThis.MutationObserver).toHaveBeenNthCalledWith(
        2,
        handleBodyElementMutationObserverUpdateSpy
      );
      expect(globalThis.MutationObserver).toHaveBeenNthCalledWith(
        3,
        handleDocumentElementMutationObserverUpdateSpy
      );
    });
  });

  describe("setupAutofillOverlayListenerOnField", () => {
    let autofillFieldElement: ElementWithOpId<FormFieldElement>;
    let autofillFieldData: AutofillField;

    beforeEach(() => {
      document.body.innerHTML = `
      <form id="validFormId">
        <input type="text" id="username-field" placeholder="username" />
        <input type="password" id="password-field" placeholder="password" />
      </form>
      `;

      autofillFieldElement = document.getElementById(
        "username-field"
      ) as ElementWithOpId<FormFieldElement>;
      autofillFieldElement.opid = "op-1";
      jest.spyOn(autofillFieldElement, "addEventListener");
      autofillFieldData = createAutofillFieldMock({
        opid: "username-field",
        form: "validFormId",
        placeholder: "username",
        elementNumber: 1,
      });
    });

    describe("skips setup for ignored form fields", () => {
      beforeEach(() => {
        autofillFieldData = mock<AutofillField>();
      });

      it("ignores fields that are readonly", () => {
        autofillFieldData.readonly = true;

        autofillOverlayContentService.setupAutofillOverlayListenerOnField(
          autofillFieldElement,
          autofillFieldData
        );

        expect(autofillFieldElement.addEventListener).not.toHaveBeenCalled();
      });

      it("ignores fields that contain a disabled attribute", () => {
        autofillFieldData.disabled = true;

        autofillOverlayContentService.setupAutofillOverlayListenerOnField(
          autofillFieldElement,
          autofillFieldData
        );

        expect(autofillFieldElement.addEventListener).not.toHaveBeenCalled();
      });

      it("ignores fields that are not viewable", () => {
        autofillFieldData.viewable = false;

        autofillOverlayContentService.setupAutofillOverlayListenerOnField(
          autofillFieldElement,
          autofillFieldData
        );

        expect(autofillFieldElement.addEventListener).not.toHaveBeenCalled();
      });

      it("ignores fields that are part of the ExcludedAutofillTypes", () => {
        AutoFillConstants.ExcludedAutofillTypes.forEach((excludedType) => {
          autofillFieldData.type = excludedType;

          autofillOverlayContentService.setupAutofillOverlayListenerOnField(
            autofillFieldElement,
            autofillFieldData
          );

          expect(autofillFieldElement.addEventListener).not.toHaveBeenCalled();
        });
      });

      it("ignores fields that contain the keyword `search`", () => {
        autofillFieldData.placeholder = "search";

        autofillOverlayContentService.setupAutofillOverlayListenerOnField(
          autofillFieldElement,
          autofillFieldData
        );

        expect(autofillFieldElement.addEventListener).not.toHaveBeenCalled();
      });

      it("ignores fields that contain the keyword `captcha` ", () => {
        autofillFieldData.placeholder = "captcha";

        autofillOverlayContentService.setupAutofillOverlayListenerOnField(
          autofillFieldElement,
          autofillFieldData
        );

        expect(autofillFieldElement.addEventListener).not.toHaveBeenCalled();
      });

      it("ignores fields that do not appear as a login field", () => {
        autofillFieldData.placeholder = "not-a-login-field";

        autofillOverlayContentService.setupAutofillOverlayListenerOnField(
          autofillFieldElement,
          autofillFieldData
        );

        expect(autofillFieldElement.addEventListener).not.toHaveBeenCalled();
      });
    });

    describe("identifies the overlay visibility setting", () => {
      it("defaults the overlay visibility setting to `OnFieldFocus` if a value is not set", async () => {
        sendExtensionMessageSpy.mockResolvedValueOnce(undefined);
        autofillOverlayContentService["autofillOverlayVisibility"] = undefined;

        await autofillOverlayContentService.setupAutofillOverlayListenerOnField(
          autofillFieldElement,
          autofillFieldData
        );

        expect(sendExtensionMessageSpy).toHaveBeenCalledWith("getAutofillOverlayVisibility");
        expect(autofillOverlayContentService["autofillOverlayVisibility"]).toEqual(
          AutofillOverlayVisibility.OnFieldFocus
        );
      });

      it("sets the overlay visibility setting to the value returned from the background script", async () => {
        sendExtensionMessageSpy.mockResolvedValueOnce(AutofillOverlayVisibility.OnFieldFocus);
        autofillOverlayContentService["autofillOverlayVisibility"] = undefined;

        await autofillOverlayContentService.setupAutofillOverlayListenerOnField(
          autofillFieldElement,
          autofillFieldData
        );

        expect(autofillOverlayContentService["autofillOverlayVisibility"]).toEqual(
          AutofillOverlayVisibility.OnFieldFocus
        );
      });
    });

    describe("sets up form field element listeners", () => {
      it("removes all cached event listeners from the form field element", async () => {
        jest.spyOn(autofillFieldElement, "removeEventListener");
        const inputHandler = jest.fn();
        const clickHandler = jest.fn();
        const focusHandler = jest.fn();
        autofillOverlayContentService["eventHandlersMemo"] = {
          "op-1-username-field-input-handler": inputHandler,
          "op-1-username-field-click-handler": clickHandler,
          "op-1-username-field-focus-handler": focusHandler,
        };

        await autofillOverlayContentService.setupAutofillOverlayListenerOnField(
          autofillFieldElement,
          autofillFieldData
        );

        expect(autofillFieldElement.removeEventListener).toHaveBeenNthCalledWith(
          1,
          "input",
          inputHandler
        );
        expect(autofillFieldElement.removeEventListener).toHaveBeenNthCalledWith(
          2,
          "click",
          clickHandler
        );
        expect(autofillFieldElement.removeEventListener).toHaveBeenNthCalledWith(
          3,
          "focus",
          focusHandler
        );
      });

      describe("form field blur event listener", () => {
        beforeEach(async () => {
          await autofillOverlayContentService.setupAutofillOverlayListenerOnField(
            autofillFieldElement,
            autofillFieldData
          );
        });

        it("updates the isFieldCurrentlyFocused value to false", async () => {
          autofillOverlayContentService["isFieldCurrentlyFocused"] = true;

          autofillFieldElement.dispatchEvent(new Event("blur"));

          expect(autofillOverlayContentService["isFieldCurrentlyFocused"]).toEqual(false);
        });

        it("sends a message to the background to check if the overlay is focused", () => {
          autofillFieldElement.dispatchEvent(new Event("blur"));

          expect(sendExtensionMessageSpy).toHaveBeenCalledWith("checkAutofillOverlayFocused");
        });
      });

      describe("form field keyup event listener", () => {
        beforeEach(async () => {
          await autofillOverlayContentService.setupAutofillOverlayListenerOnField(
            autofillFieldElement,
            autofillFieldData
          );
          jest.spyOn(globalThis.customElements, "define").mockImplementation();
        });

        it("removes the autofill overlay when the `Escape` key is pressed", () => {
          jest.spyOn(autofillOverlayContentService as any, "removeAutofillOverlay");

          autofillFieldElement.dispatchEvent(new KeyboardEvent("keyup", { code: "Escape" }));

          expect(autofillOverlayContentService.removeAutofillOverlay).toHaveBeenCalled();
        });

        it("repositions the overlay if autofill is not currently filling when the `Enter` key is pressed", () => {
          const handleOverlayRepositionEventSpy = jest.spyOn(
            autofillOverlayContentService as any,
            "handleOverlayRepositionEvent"
          );
          autofillOverlayContentService["isCurrentlyFilling"] = false;

          autofillFieldElement.dispatchEvent(new KeyboardEvent("keyup", { code: "Enter" }));

          expect(handleOverlayRepositionEventSpy).toHaveBeenCalled();
        });

        it("skips repositioning the overlay if autofill is currently filling when the `Enter` key is pressed", () => {
          const handleOverlayRepositionEventSpy = jest.spyOn(
            autofillOverlayContentService as any,
            "handleOverlayRepositionEvent"
          );
          autofillOverlayContentService["isCurrentlyFilling"] = true;

          autofillFieldElement.dispatchEvent(new KeyboardEvent("keyup", { code: "Enter" }));

          expect(handleOverlayRepositionEventSpy).not.toHaveBeenCalled();
        });

        it("opens the overlay list and focuses it after a delay if it is not visible when the `ArrowDown` key is pressed", async () => {
          jest.useFakeTimers();
          const updateMostRecentlyFocusedFieldSpy = jest.spyOn(
            autofillOverlayContentService as any,
            "updateMostRecentlyFocusedField"
          );
          const openAutofillOverlaySpy = jest.spyOn(
            autofillOverlayContentService as any,
            "openAutofillOverlay"
          );
          autofillOverlayContentService["isOverlayListVisible"] = false;

          autofillFieldElement.dispatchEvent(new KeyboardEvent("keyup", { code: "ArrowDown" }));
          await flushPromises();

          expect(updateMostRecentlyFocusedFieldSpy).toHaveBeenCalledWith(autofillFieldElement);
          expect(openAutofillOverlaySpy).toHaveBeenCalledWith({ isOpeningFullOverlay: true });
          expect(sendExtensionMessageSpy).not.toHaveBeenCalledWith("focusAutofillOverlayList");

          jest.advanceTimersByTime(150);

          expect(sendExtensionMessageSpy).toHaveBeenCalledWith("focusAutofillOverlayList");
        });

        it("focuses the overlay list when the `ArrowDown` key is pressed", () => {
          autofillOverlayContentService["isOverlayListVisible"] = true;

          autofillFieldElement.dispatchEvent(new KeyboardEvent("keyup", { code: "ArrowDown" }));

          expect(sendExtensionMessageSpy).toHaveBeenCalledWith("focusAutofillOverlayList");
        });
      });

      describe("form field input change event listener", () => {
        beforeEach(() => {
          jest.spyOn(globalThis.customElements, "define").mockImplementation();
        });

        it("ignores span elements that trigger the listener", async () => {
          const spanAutofillFieldElement = document.createElement(
            "span"
          ) as ElementWithOpId<HTMLSpanElement>;
          jest.spyOn(autofillOverlayContentService as any, "storeModifiedFormElement");

          await autofillOverlayContentService.setupAutofillOverlayListenerOnField(
            spanAutofillFieldElement,
            autofillFieldData
          );

          spanAutofillFieldElement.dispatchEvent(new Event("input"));

          expect(autofillOverlayContentService["storeModifiedFormElement"]).not.toHaveBeenCalled();
        });

        it("stores the field as a user filled field if the form field data indicates that it is for a username", async () => {
          await autofillOverlayContentService.setupAutofillOverlayListenerOnField(
            autofillFieldElement,
            autofillFieldData
          );
          autofillFieldElement.dispatchEvent(new Event("input"));

          expect(autofillOverlayContentService["userFilledFields"].username).toEqual(
            autofillFieldElement
          );
        });

        it("stores the field as a user filled field if the form field is of type password", async () => {
          const passwordFieldElement = document.getElementById(
            "password-field"
          ) as ElementWithOpId<FormFieldElement>;

          await autofillOverlayContentService.setupAutofillOverlayListenerOnField(
            passwordFieldElement,
            autofillFieldData
          );
          passwordFieldElement.dispatchEvent(new Event("input"));

          expect(autofillOverlayContentService["userFilledFields"].password).toEqual(
            passwordFieldElement
          );
        });

        it("removes the overlay if the form field element has a value and the user is not authed", async () => {
          jest.spyOn(autofillOverlayContentService as any, "isUserAuthed").mockReturnValue(false);
          const removeAutofillOverlayListSpy = jest.spyOn(
            autofillOverlayContentService as any,
            "removeAutofillOverlayList"
          );
          (autofillFieldElement as HTMLInputElement).value = "test";

          await autofillOverlayContentService.setupAutofillOverlayListenerOnField(
            autofillFieldElement,
            autofillFieldData
          );
          autofillFieldElement.dispatchEvent(new Event("input"));

          expect(removeAutofillOverlayListSpy).toHaveBeenCalled();
        });

        it("removes the overlay if the form field element has a value and the overlay ciphers are populated", async () => {
          jest.spyOn(autofillOverlayContentService as any, "isUserAuthed").mockReturnValue(true);
          autofillOverlayContentService["isOverlayCiphersPopulated"] = true;
          const removeAutofillOverlayListSpy = jest.spyOn(
            autofillOverlayContentService as any,
            "removeAutofillOverlayList"
          );
          (autofillFieldElement as HTMLInputElement).value = "test";

          await autofillOverlayContentService.setupAutofillOverlayListenerOnField(
            autofillFieldElement,
            autofillFieldData
          );
          autofillFieldElement.dispatchEvent(new Event("input"));

          expect(removeAutofillOverlayListSpy).toHaveBeenCalled();
        });

        it("opens the autofill overlay if the form field is empty", async () => {
          jest.spyOn(autofillOverlayContentService as any, "openAutofillOverlay");
          (autofillFieldElement as HTMLInputElement).value = "";

          await autofillOverlayContentService.setupAutofillOverlayListenerOnField(
            autofillFieldElement,
            autofillFieldData
          );
          autofillFieldElement.dispatchEvent(new Event("input"));

          expect(autofillOverlayContentService["openAutofillOverlay"]).toHaveBeenCalled();
        });

        it("opens the autofill overlay if the form field is empty and the user is authed", async () => {
          jest.spyOn(autofillOverlayContentService as any, "isUserAuthed").mockReturnValue(true);
          jest.spyOn(autofillOverlayContentService as any, "openAutofillOverlay");
          (autofillFieldElement as HTMLInputElement).value = "";

          await autofillOverlayContentService.setupAutofillOverlayListenerOnField(
            autofillFieldElement,
            autofillFieldData
          );
          autofillFieldElement.dispatchEvent(new Event("input"));

          expect(autofillOverlayContentService["openAutofillOverlay"]).toHaveBeenCalled();
        });

        it("opens the autofill overlay if the form field is empty and the overlay ciphers are not populated", async () => {
          jest.spyOn(autofillOverlayContentService as any, "isUserAuthed").mockReturnValue(false);
          autofillOverlayContentService["isOverlayCiphersPopulated"] = false;
          jest.spyOn(autofillOverlayContentService as any, "openAutofillOverlay");
          (autofillFieldElement as HTMLInputElement).value = "";

          await autofillOverlayContentService.setupAutofillOverlayListenerOnField(
            autofillFieldElement,
            autofillFieldData
          );
          autofillFieldElement.dispatchEvent(new Event("input"));

          expect(autofillOverlayContentService["openAutofillOverlay"]).toHaveBeenCalled();
        });
      });

      describe("form field click event listener", () => {
        beforeEach(async () => {
          jest
            .spyOn(autofillOverlayContentService as any, "triggerFormFieldFocusedAction")
            .mockImplementation();
          autofillOverlayContentService["isOverlayListVisible"] = false;
          autofillOverlayContentService["isOverlayListVisible"] = false;
          await autofillOverlayContentService.setupAutofillOverlayListenerOnField(
            autofillFieldElement,
            autofillFieldData
          );
        });

        it("triggers the field focused handler if the overlay is not visible", async () => {
          autofillFieldElement.dispatchEvent(new Event("click"));

          expect(autofillOverlayContentService["triggerFormFieldFocusedAction"]).toHaveBeenCalled();
        });

        it("skips triggering the field focused handler if the overlay list is visible", () => {
          autofillOverlayContentService["isOverlayListVisible"] = true;

          autofillFieldElement.dispatchEvent(new Event("click"));

          expect(
            autofillOverlayContentService["triggerFormFieldFocusedAction"]
          ).not.toHaveBeenCalled();
        });

        it("skips triggering the field focused handler if the overlay button is visible", () => {
          autofillOverlayContentService["isOverlayButtonVisible"] = true;

          autofillFieldElement.dispatchEvent(new Event("click"));

          expect(
            autofillOverlayContentService["triggerFormFieldFocusedAction"]
          ).not.toHaveBeenCalled();
        });
      });

      describe("form field focus event listener", () => {
        let updateMostRecentlyFocusedFieldSpy: jest.SpyInstance;

        beforeEach(() => {
          jest.spyOn(globalThis.customElements, "define").mockImplementation();
          updateMostRecentlyFocusedFieldSpy = jest.spyOn(
            autofillOverlayContentService as any,
            "updateMostRecentlyFocusedField"
          );
          autofillOverlayContentService["isCurrentlyFilling"] = false;
        });

        it("skips triggering the handler logic if autofill is currently filling", async () => {
          autofillOverlayContentService["isCurrentlyFilling"] = true;
          autofillOverlayContentService["mostRecentlyFocusedField"] = autofillFieldElement;
          autofillOverlayContentService["autofillOverlayVisibility"] =
            AutofillOverlayVisibility.OnFieldFocus;
          await autofillOverlayContentService.setupAutofillOverlayListenerOnField(
            autofillFieldElement,
            autofillFieldData
          );

          autofillFieldElement.dispatchEvent(new Event("focus"));

          expect(updateMostRecentlyFocusedFieldSpy).not.toHaveBeenCalled();
        });

        it("updates the most recently focused field", async () => {
          await autofillOverlayContentService.setupAutofillOverlayListenerOnField(
            autofillFieldElement,
            autofillFieldData
          );

          autofillFieldElement.dispatchEvent(new Event("focus"));

          expect(updateMostRecentlyFocusedFieldSpy).toHaveBeenCalledWith(autofillFieldElement);
          expect(autofillOverlayContentService["mostRecentlyFocusedField"]).toEqual(
            autofillFieldElement
          );
        });

        it("removes the overlay list if the autofill visibility is set to onClick", async () => {
          autofillOverlayContentService["overlayListElement"] = document.createElement("div");
          autofillOverlayContentService["autofillOverlayVisibility"] =
            AutofillOverlayVisibility.OnButtonClick;
          await autofillOverlayContentService.setupAutofillOverlayListenerOnField(
            autofillFieldElement,
            autofillFieldData
          );

          autofillFieldElement.dispatchEvent(new Event("focus"));
          await flushPromises();

          expect(sendExtensionMessageSpy).toHaveBeenCalledWith("autofillOverlayElementClosed", {
            overlayElement: "autofill-overlay-list",
          });
        });

        it("removes the overlay list if the form element has a value and the focused field is newly focused", async () => {
          autofillOverlayContentService["overlayListElement"] = document.createElement("div");
          autofillOverlayContentService["mostRecentlyFocusedField"] = document.createElement(
            "input"
          ) as ElementWithOpId<HTMLInputElement>;
          (autofillFieldElement as HTMLInputElement).value = "test";
          await autofillOverlayContentService.setupAutofillOverlayListenerOnField(
            autofillFieldElement,
            autofillFieldData
          );

          autofillFieldElement.dispatchEvent(new Event("focus"));
          await flushPromises();

          expect(sendExtensionMessageSpy).toHaveBeenCalledWith("autofillOverlayElementClosed", {
            overlayElement: "autofill-overlay-list",
          });
        });

        it("opens the autofill overlay if the form element has no value", async () => {
          autofillOverlayContentService["overlayListElement"] = document.createElement("div");
          (autofillFieldElement as HTMLInputElement).value = "";
          autofillOverlayContentService["autofillOverlayVisibility"] =
            AutofillOverlayVisibility.OnFieldFocus;
          await autofillOverlayContentService.setupAutofillOverlayListenerOnField(
            autofillFieldElement,
            autofillFieldData
          );

          autofillFieldElement.dispatchEvent(new Event("focus"));
          await flushPromises();

          expect(sendExtensionMessageSpy).toHaveBeenCalledWith("openAutofillOverlay");
        });

        it("opens the autofill overlay if the overlay ciphers are not populated and the user is authed", async () => {
          autofillOverlayContentService["overlayListElement"] = document.createElement("div");
          (autofillFieldElement as HTMLInputElement).value = "";
          autofillOverlayContentService["autofillOverlayVisibility"] =
            AutofillOverlayVisibility.OnFieldFocus;
          jest.spyOn(autofillOverlayContentService as any, "isUserAuthed").mockReturnValue(true);
          await autofillOverlayContentService.setupAutofillOverlayListenerOnField(
            autofillFieldElement,
            autofillFieldData
          );

          autofillFieldElement.dispatchEvent(new Event("focus"));
          await flushPromises();

          expect(sendExtensionMessageSpy).toHaveBeenCalledWith("openAutofillOverlay");
        });

        it("updates the overlay button position if the focus event is not opening the overlay", async () => {
          autofillOverlayContentService["autofillOverlayVisibility"] =
            AutofillOverlayVisibility.OnFieldFocus;
          (autofillFieldElement as HTMLInputElement).value = "test";
          autofillOverlayContentService["isOverlayCiphersPopulated"] = true;
          await autofillOverlayContentService.setupAutofillOverlayListenerOnField(
            autofillFieldElement,
            autofillFieldData
          );

          autofillFieldElement.dispatchEvent(new Event("focus"));
          await flushPromises();

          expect(sendExtensionMessageSpy).toHaveBeenCalledWith("updateAutofillOverlayPosition", {
            overlayElement: AutofillOverlayElement.Button,
          });
        });
      });
    });

    it("triggers the form field focused handler if the current active element in the document is the passed form field", async () => {
      const documentRoot = autofillFieldElement.getRootNode() as Document;
      Object.defineProperty(documentRoot, "activeElement", {
        value: autofillFieldElement,
        writable: true,
      });

      await autofillOverlayContentService.setupAutofillOverlayListenerOnField(
        autofillFieldElement,
        autofillFieldData
      );

      expect(sendExtensionMessageSpy).toHaveBeenCalledWith("openAutofillOverlay");
      expect(autofillOverlayContentService["mostRecentlyFocusedField"]).toEqual(
        autofillFieldElement
      );
    });

    it("sets the most recently focused field to the passed form field element if the value is not set", async () => {
      autofillOverlayContentService["mostRecentlyFocusedField"] = undefined;

      await autofillOverlayContentService.setupAutofillOverlayListenerOnField(
        autofillFieldElement,
        autofillFieldData
      );

      expect(autofillOverlayContentService["mostRecentlyFocusedField"]).toEqual(
        autofillFieldElement
      );
    });
  });

  describe("openAutofillOverlay", () => {
    let autofillFieldElement: ElementWithOpId<FormFieldElement>;

    beforeEach(() => {
      document.body.innerHTML = `
      <form id="validFormId">
        <input type="text" id="username-field" placeholder="username" />
        <input type="password" id="password-field" placeholder="password" />
      </form>
      `;

      autofillFieldElement = document.getElementById(
        "username-field"
      ) as ElementWithOpId<FormFieldElement>;
      autofillFieldElement.opid = "op-1";
      autofillOverlayContentService["mostRecentlyFocusedField"] = autofillFieldElement;
    });

    it("skips opening the overlay if a field has not been recently focused", () => {
      autofillOverlayContentService["mostRecentlyFocusedField"] = undefined;

      autofillOverlayContentService["openAutofillOverlay"]();

      expect(sendExtensionMessageSpy).not.toHaveBeenCalled();
    });

    it("focuses the most recent overlay field if the field is not focused", () => {
      jest.spyOn(autofillFieldElement, "getRootNode").mockReturnValue(document);
      Object.defineProperty(document, "activeElement", {
        value: document.createElement("div"),
        writable: true,
      });
      const focusMostRecentOverlayFieldSpy = jest.spyOn(
        autofillOverlayContentService as any,
        "focusMostRecentOverlayField"
      );

      autofillOverlayContentService["openAutofillOverlay"]({ isFocusingFieldElement: true });

      expect(focusMostRecentOverlayFieldSpy).toHaveBeenCalled();
    });

    it("skips focusing the most recent overlay field if the field is already focused", () => {
      jest.spyOn(autofillFieldElement, "getRootNode").mockReturnValue(document);
      Object.defineProperty(document, "activeElement", {
        value: autofillFieldElement,
        writable: true,
      });
      const focusMostRecentOverlayFieldSpy = jest.spyOn(
        autofillOverlayContentService as any,
        "focusMostRecentOverlayField"
      );

      autofillOverlayContentService["openAutofillOverlay"]({ isFocusingFieldElement: true });

      expect(focusMostRecentOverlayFieldSpy).not.toHaveBeenCalled();
    });

    it("stores the user's auth status", () => {
      autofillOverlayContentService["authStatus"] = undefined;

      autofillOverlayContentService["openAutofillOverlay"]({
        authStatus: AuthenticationStatus.Unlocked,
      });

      expect(autofillOverlayContentService["authStatus"]).toEqual(AuthenticationStatus.Unlocked);
    });

    it("opens both autofill overlay elements", () => {
      autofillOverlayContentService["mostRecentlyFocusedField"] = autofillFieldElement;

      autofillOverlayContentService["openAutofillOverlay"]();

      expect(sendExtensionMessageSpy).toHaveBeenCalledWith("updateAutofillOverlayPosition", {
        overlayElement: AutofillOverlayElement.Button,
      });
      expect(sendExtensionMessageSpy).toHaveBeenCalledWith("updateAutofillOverlayPosition", {
        overlayElement: AutofillOverlayElement.List,
      });
    });

    it("opens the autofill overlay button only if overlay visibility is set for onButtonClick", () => {
      autofillOverlayContentService["autofillOverlayVisibility"] =
        AutofillOverlayVisibility.OnButtonClick;

      autofillOverlayContentService["openAutofillOverlay"]({ isOpeningFullOverlay: false });

      expect(sendExtensionMessageSpy).toHaveBeenCalledWith("updateAutofillOverlayPosition", {
        overlayElement: AutofillOverlayElement.Button,
      });
      expect(sendExtensionMessageSpy).not.toHaveBeenCalledWith("updateAutofillOverlayPosition", {
        overlayElement: AutofillOverlayElement.List,
      });
    });

    it("overrides the onButtonClick visibility setting to open both overlay elements", () => {
      autofillOverlayContentService["autofillOverlayVisibility"] =
        AutofillOverlayVisibility.OnButtonClick;

      autofillOverlayContentService["openAutofillOverlay"]({ isOpeningFullOverlay: true });

      expect(sendExtensionMessageSpy).toHaveBeenCalledWith("updateAutofillOverlayPosition", {
        overlayElement: AutofillOverlayElement.Button,
      });
      expect(sendExtensionMessageSpy).toHaveBeenCalledWith("updateAutofillOverlayPosition", {
        overlayElement: AutofillOverlayElement.List,
      });
    });

    it("sends an extension message requesting an re-collection of page details if they need to update", () => {
      jest.spyOn(autofillOverlayContentService as any, "sendExtensionMessage");
      autofillOverlayContentService.pageDetailsUpdateRequired = true;

      autofillOverlayContentService["openAutofillOverlay"]();

      expect(sendExtensionMessageSpy).toHaveBeenCalledWith("bgCollectPageDetails", {
        sender: "autofillOverlayContentService",
      });
    });
  });

  describe("focusMostRecentOverlayField", () => {
    it("focuses the most recently focused overlay field", () => {
      const mostRecentlyFocusedField = document.createElement(
        "input"
      ) as ElementWithOpId<HTMLInputElement>;
      autofillOverlayContentService["mostRecentlyFocusedField"] = mostRecentlyFocusedField;
      jest.spyOn(mostRecentlyFocusedField, "focus");

      autofillOverlayContentService["focusMostRecentOverlayField"]();

      expect(mostRecentlyFocusedField.focus).toHaveBeenCalled();
    });
  });

  describe("blurMostRecentOverlayField", () => {
    it("removes focus from the most recently focused overlay field", () => {
      const mostRecentlyFocusedField = document.createElement(
        "input"
      ) as ElementWithOpId<HTMLInputElement>;
      autofillOverlayContentService["mostRecentlyFocusedField"] = mostRecentlyFocusedField;
      jest.spyOn(mostRecentlyFocusedField, "blur");

      autofillOverlayContentService["blurMostRecentOverlayField"]();

      expect(mostRecentlyFocusedField.blur).toHaveBeenCalled();
    });
  });

  describe("removeAutofillOverlay", () => {
    it("disconnects the body's mutation observer", () => {
      const bodyMutationObserver = mock<MutationObserver>();
      autofillOverlayContentService["bodyElementMutationObserver"] = bodyMutationObserver;

      autofillOverlayContentService.removeAutofillOverlay();

      expect(bodyMutationObserver.disconnect).toHaveBeenCalled();
    });
  });

  describe("removeAutofillOverlayButton", () => {
    beforeEach(() => {
      document.body.innerHTML = `<div class="overlay-button"></div>`;
      autofillOverlayContentService["overlayButtonElement"] = document.querySelector(
        ".overlay-button"
      ) as HTMLElement;
    });

    it("removes the overlay button from the DOM", () => {
      const overlayButtonElement = document.querySelector(".overlay-button") as HTMLElement;
      autofillOverlayContentService["isOverlayButtonVisible"] = true;

      autofillOverlayContentService.removeAutofillOverlay();

      expect(autofillOverlayContentService["isOverlayButtonVisible"]).toEqual(false);
      expect(document.body.contains(overlayButtonElement)).toEqual(false);
    });

    it("sends a message to the background indicating that the overlay button has been closed", () => {
      autofillOverlayContentService.removeAutofillOverlay();

      expect(sendExtensionMessageSpy).toHaveBeenCalledWith("autofillOverlayElementClosed", {
        overlayElement: AutofillOverlayElement.Button,
      });
    });

    it("removes the overlay reposition event listeners", () => {
      jest.spyOn(globalThis.document.body, "removeEventListener");
      jest.spyOn(globalThis, "removeEventListener");
      const handleOverlayRepositionEventSpy = jest.spyOn(
        autofillOverlayContentService as any,
        "handleOverlayRepositionEvent"
      );

      autofillOverlayContentService.removeAutofillOverlay();

      expect(globalThis.removeEventListener).toHaveBeenCalledWith(
        EVENTS.SCROLL,
        handleOverlayRepositionEventSpy,
        {
          capture: true,
        }
      );
      expect(globalThis.removeEventListener).toHaveBeenCalledWith(
        EVENTS.RESIZE,
        handleOverlayRepositionEventSpy
      );
    });
  });

  describe("removeAutofillOverlayList", () => {
    beforeEach(() => {
      document.body.innerHTML = `<div class="overlay-list"></div>`;
      autofillOverlayContentService["overlayListElement"] = document.querySelector(
        ".overlay-list"
      ) as HTMLElement;
    });

    it("removes the overlay list element from the dom", () => {
      const overlayListElement = document.querySelector(".overlay-list") as HTMLElement;
      autofillOverlayContentService["isOverlayListVisible"] = true;

      autofillOverlayContentService.removeAutofillOverlay();

      expect(autofillOverlayContentService["isOverlayListVisible"]).toEqual(false);
      expect(document.body.contains(overlayListElement)).toEqual(false);
    });

    it("sends a message to the extension background indicating that the overlay list has closed", () => {
      autofillOverlayContentService.removeAutofillOverlay();

      expect(sendExtensionMessageSpy).toHaveBeenCalledWith("autofillOverlayElementClosed", {
        overlayElement: AutofillOverlayElement.List,
      });
    });
  });

  describe("addNewVaultItem", () => {
    it("skips sending the message if the overlay list is not visible", () => {
      autofillOverlayContentService["isOverlayListVisible"] = false;

      autofillOverlayContentService.addNewVaultItem();

      expect(sendExtensionMessageSpy).not.toHaveBeenCalled();
    });

    it("sends a message that facilitates adding a new vault item with empty fields", () => {
      autofillOverlayContentService["isOverlayListVisible"] = true;

      autofillOverlayContentService.addNewVaultItem();

      expect(sendExtensionMessageSpy).toHaveBeenCalledWith("autofillOverlayAddNewVaultItem", {
        login: {
          username: "",
          password: "",
          uri: "http://localhost/",
          hostname: "localhost",
        },
      });
    });

    it("sends a message that facilitates adding a new vault item with data from user filled fields", () => {
      document.body.innerHTML = `
      <form id="validFormId">
        <input type="text" id="username-field" placeholder="username" />
        <input type="password" id="password-field" placeholder="password" />
      </form>
      `;
      const usernameField = document.getElementById(
        "username-field"
      ) as ElementWithOpId<HTMLInputElement>;
      const passwordField = document.getElementById(
        "password-field"
      ) as ElementWithOpId<HTMLInputElement>;
      usernameField.value = "test-username";
      passwordField.value = "test-password";
      autofillOverlayContentService["isOverlayListVisible"] = true;
      autofillOverlayContentService["userFilledFields"] = {
        username: usernameField,
        password: passwordField,
      };

      autofillOverlayContentService.addNewVaultItem();

      expect(sendExtensionMessageSpy).toHaveBeenCalledWith("autofillOverlayAddNewVaultItem", {
        login: {
          username: "test-username",
          password: "test-password",
          uri: "http://localhost/",
          hostname: "localhost",
        },
      });
    });
  });

  describe("redirectOverlayFocusOut", () => {
    let autofillFieldElement: ElementWithOpId<FormFieldElement>;
    let autofillFieldFocusSpy: jest.SpyInstance;
    let findTabsSpy: jest.SpyInstance;
    let previousFocusableElement: HTMLElement;
    let nextFocusableElement: HTMLElement;

    beforeEach(() => {
      document.body.innerHTML = `
      <div class="previous-focusable-element" tabindex="0"></div>
      <form id="validFormId">
        <input type="text" id="username-field" placeholder="username" />
        <input type="password" id="password-field" placeholder="password" />
      </form>
      <div class="next-focusable-element" tabindex="0"></div>
      `;
      autofillFieldElement = document.getElementById(
        "username-field"
      ) as ElementWithOpId<FormFieldElement>;
      autofillFieldElement.opid = "op-1";
      previousFocusableElement = document.querySelector(
        ".previous-focusable-element"
      ) as HTMLElement;
      nextFocusableElement = document.querySelector(".next-focusable-element") as HTMLElement;
      autofillFieldFocusSpy = jest.spyOn(autofillFieldElement, "focus");
      findTabsSpy = jest.spyOn(autofillOverlayContentService as any, "findTabs");
      autofillOverlayContentService["isOverlayListVisible"] = true;
      autofillOverlayContentService["mostRecentlyFocusedField"] = autofillFieldElement;
      autofillOverlayContentService["focusableElements"] = [
        previousFocusableElement,
        autofillFieldElement,
        nextFocusableElement,
      ];
    });

    it("skips focusing an element if the overlay is not visible", () => {
      autofillOverlayContentService["isOverlayListVisible"] = false;

      autofillOverlayContentService.redirectOverlayFocusOut(RedirectFocusDirection.Next);

      expect(findTabsSpy).not.toHaveBeenCalled();
    });

    it("skips focusing an element if no recently focused field exists", () => {
      autofillOverlayContentService["mostRecentlyFocusedField"] = undefined;

      autofillOverlayContentService.redirectOverlayFocusOut(RedirectFocusDirection.Next);

      expect(findTabsSpy).not.toHaveBeenCalled();
    });

    it("focuses the most recently focused field if the focus direction is `Current`", () => {
      autofillOverlayContentService.redirectOverlayFocusOut(RedirectFocusDirection.Current);

      expect(findTabsSpy).not.toHaveBeenCalled();
      expect(autofillFieldFocusSpy).toHaveBeenCalled();
    });

    it("removes the overlay if the focus direction is `Current`", () => {
      jest.useFakeTimers();
      const removeAutofillOverlaySpy = jest.spyOn(
        autofillOverlayContentService as any,
        "removeAutofillOverlay"
      );

      autofillOverlayContentService.redirectOverlayFocusOut(RedirectFocusDirection.Current);
      jest.advanceTimersByTime(150);

      expect(removeAutofillOverlaySpy).toHaveBeenCalled();
    });

    it("finds all focusable tabs if the focusable elements array is not populated", () => {
      autofillOverlayContentService["focusableElements"] = [];
      findTabsSpy.mockReturnValue([
        previousFocusableElement,
        autofillFieldElement,
        nextFocusableElement,
      ]);

      autofillOverlayContentService.redirectOverlayFocusOut(RedirectFocusDirection.Next);

      expect(findTabsSpy).toHaveBeenCalledWith(globalThis.document.body, { getShadowRoot: true });
    });

    it("focuses the previous focusable element if the focus direction is `Previous`", () => {
      jest.spyOn(previousFocusableElement, "focus");

      autofillOverlayContentService.redirectOverlayFocusOut(RedirectFocusDirection.Previous);

      expect(autofillFieldFocusSpy).not.toHaveBeenCalled();
      expect(previousFocusableElement.focus).toHaveBeenCalled();
    });

    it("focuses the next focusable element if the focus direction is `Next`", () => {
      jest.spyOn(nextFocusableElement, "focus");

      autofillOverlayContentService.redirectOverlayFocusOut(RedirectFocusDirection.Next);

      expect(autofillFieldFocusSpy).not.toHaveBeenCalled();
      expect(nextFocusableElement.focus).toHaveBeenCalled();
    });
  });

  describe("handleOverlayRepositionEvent", () => {
    beforeEach(() => {
      document.body.innerHTML = `
      <form id="validFormId">
        <input type="text" id="username-field" placeholder="username" />
        <input type="password" id="password-field" placeholder="password" />
      </form>
      `;
      const usernameField = document.getElementById(
        "username-field"
      ) as ElementWithOpId<HTMLInputElement>;
      autofillOverlayContentService["mostRecentlyFocusedField"] = usernameField;
      autofillOverlayContentService["setOverlayRepositionEventListeners"]();
      autofillOverlayContentService["isOverlayButtonVisible"] = true;
      autofillOverlayContentService["isOverlayListVisible"] = true;
      jest
        .spyOn(autofillOverlayContentService as any, "recentlyFocusedFieldIsCurrentlyFocused")
        .mockReturnValue(true);
    });

    it("skips handling the overlay reposition event if the overlay button and list elements are not visible", () => {
      autofillOverlayContentService["isOverlayButtonVisible"] = false;
      autofillOverlayContentService["isOverlayListVisible"] = false;

      globalThis.dispatchEvent(new Event(EVENTS.RESIZE));

      expect(sendExtensionMessageSpy).not.toHaveBeenCalled();
    });

    it("hides the overlay elements", () => {
      globalThis.dispatchEvent(new Event(EVENTS.SCROLL));

      expect(sendExtensionMessageSpy).toHaveBeenCalledWith("updateAutofillOverlayHidden", {
        display: "none",
      });
      expect(autofillOverlayContentService["isOverlayButtonVisible"]).toEqual(false);
      expect(autofillOverlayContentService["isOverlayListVisible"]).toEqual(false);
    });

    it("clears the user interaction timeout", () => {
      jest.useFakeTimers();
      const clearTimeoutSpy = jest.spyOn(globalThis, "clearTimeout");
      autofillOverlayContentService["userInteractionEventTimeout"] = setTimeout(jest.fn(), 123);

      globalThis.dispatchEvent(new Event(EVENTS.SCROLL));

      expect(clearTimeoutSpy).toHaveBeenCalledWith(expect.anything());
    });

    it("removes the overlay completely if the field is not focused", () => {
      jest.useFakeTimers();
      jest
        .spyOn(autofillOverlayContentService as any, "recentlyFocusedFieldIsCurrentlyFocused")
        .mockReturnValue(false);
      const removeAutofillOverlaySpy = jest.spyOn(
        autofillOverlayContentService as any,
        "removeAutofillOverlay"
      );
      autofillOverlayContentService["mostRecentlyFocusedField"] = undefined;

      globalThis.dispatchEvent(new Event(EVENTS.SCROLL));
      jest.advanceTimersByTime(800);

      expect(sendExtensionMessageSpy).toHaveBeenCalledWith("updateAutofillOverlayHidden", {
        display: "block",
      });
      expect(autofillOverlayContentService["isOverlayButtonVisible"]).toEqual(true);
      expect(autofillOverlayContentService["isOverlayListVisible"]).toEqual(true);
      expect(removeAutofillOverlaySpy).toHaveBeenCalled();
    });

    it("updates the overlay position if the most recently focused field is still within the viewport", async () => {
      jest.useFakeTimers();
      jest
        .spyOn(autofillOverlayContentService as any, "updateMostRecentlyFocusedField")
        .mockImplementation(() => {
          autofillOverlayContentService["focusedFieldData"] = {
            focusedFieldRects: {
              top: 100,
            },
            focusedFieldStyles: {},
          };
        });
      const clearUserInteractionEventTimeoutSpy = jest.spyOn(
        autofillOverlayContentService as any,
        "clearUserInteractionEventTimeout"
      );

      globalThis.dispatchEvent(new Event(EVENTS.SCROLL));
      jest.advanceTimersByTime(800);
      await flushPromises();

      expect(sendExtensionMessageSpy).toHaveBeenCalledWith("updateAutofillOverlayPosition", {
        overlayElement: AutofillOverlayElement.Button,
      });
      expect(sendExtensionMessageSpy).toHaveBeenCalledWith("updateAutofillOverlayPosition", {
        overlayElement: AutofillOverlayElement.List,
      });
      expect(clearUserInteractionEventTimeoutSpy).toHaveBeenCalled();
    });

    it("removes the autofill overlay if the focused field is outside of the viewport", async () => {
      jest.useFakeTimers();
      jest
        .spyOn(autofillOverlayContentService as any, "updateMostRecentlyFocusedField")
        .mockImplementation(() => {
          autofillOverlayContentService["focusedFieldData"] = {
            focusedFieldRects: {
              top: 4000,
            },
            focusedFieldStyles: {},
          };
        });
      const removeAutofillOverlaySpy = jest.spyOn(
        autofillOverlayContentService as any,
        "removeAutofillOverlay"
      );

      globalThis.dispatchEvent(new Event(EVENTS.SCROLL));
      jest.advanceTimersByTime(800);
      await flushPromises();

      expect(removeAutofillOverlaySpy).toHaveBeenCalled();
    });
  });

  describe("handleOverlayElementMutationObserverUpdate", () => {
    let usernameField: ElementWithOpId<HTMLInputElement>;

    beforeEach(() => {
      document.body.innerHTML = `
      <form id="validFormId">
        <input type="text" id="username-field" placeholder="username" />
        <input type="password" id="password-field" placeholder="password" />
      </form>
      `;
      usernameField = document.getElementById(
        "username-field"
      ) as ElementWithOpId<HTMLInputElement>;
      usernameField.style.setProperty("display", "block", "important");
      jest.spyOn(usernameField, "removeAttribute");
      jest.spyOn(usernameField.style, "setProperty");
      jest
        .spyOn(
          autofillOverlayContentService as any,
          "isTriggeringExcessiveMutationObserverIterations"
        )
        .mockReturnValue(false);
    });

    it("skips handling the mutation if excessive mutation observer events are triggered", () => {
      jest
        .spyOn(
          autofillOverlayContentService as any,
          "isTriggeringExcessiveMutationObserverIterations"
        )
        .mockReturnValue(true);

      autofillOverlayContentService["handleOverlayElementMutationObserverUpdate"]([
        mock<MutationRecord>({
          target: usernameField,
        }),
      ]);

      expect(usernameField.removeAttribute).not.toHaveBeenCalled();
    });

    it("skips handling the mutation if the record type is not for `attributes`", () => {
      autofillOverlayContentService["handleOverlayElementMutationObserverUpdate"]([
        mock<MutationRecord>({
          target: usernameField,
          type: "childList",
        }),
      ]);

      expect(usernameField.removeAttribute).not.toHaveBeenCalled();
    });

    it("removes all element attributes that are not the style attribute", () => {
      autofillOverlayContentService["handleOverlayElementMutationObserverUpdate"]([
        mock<MutationRecord>({
          target: usernameField,
          type: "attributes",
          attributeName: "placeholder",
        }),
      ]);

      expect(usernameField.removeAttribute).toHaveBeenCalledWith("placeholder");
    });

    it("removes all attached style attributes and sets the default styles", () => {
      autofillOverlayContentService["handleOverlayElementMutationObserverUpdate"]([
        mock<MutationRecord>({
          target: usernameField,
          type: "attributes",
          attributeName: "style",
        }),
      ]);

      expect(usernameField.removeAttribute).toHaveBeenCalledWith("style");
      expect(usernameField.style.setProperty).toHaveBeenCalledWith("all", "initial", "important");
      expect(usernameField.style.setProperty).toHaveBeenCalledWith(
        "position",
        "fixed",
        "important"
      );
      expect(usernameField.style.setProperty).toHaveBeenCalledWith("display", "block", "important");
    });
  });

  describe("handleBodyElementMutationObserverUpdate", () => {
    let overlayButtonElement: HTMLElement;
    let overlayListElement: HTMLElement;

    beforeEach(() => {
      document.body.innerHTML = `
      <div class="overlay-button"></div>
      <div class="overlay-list"></div>
      `;
      overlayButtonElement = document.querySelector(".overlay-button") as HTMLElement;
      overlayListElement = document.querySelector(".overlay-list") as HTMLElement;
      autofillOverlayContentService["overlayButtonElement"] = overlayButtonElement;
      autofillOverlayContentService["overlayListElement"] = overlayListElement;
      autofillOverlayContentService["isOverlayListVisible"] = true;
      jest.spyOn(globalThis.document.body, "insertBefore");
      jest
        .spyOn(
          autofillOverlayContentService as any,
          "isTriggeringExcessiveMutationObserverIterations"
        )
        .mockReturnValue(false);
    });

    it("skips handling the mutation if the overlay elements are not present in the DOM", () => {
      autofillOverlayContentService["overlayButtonElement"] = undefined;
      autofillOverlayContentService["overlayListElement"] = undefined;

      autofillOverlayContentService["handleBodyElementMutationObserverUpdate"]();

      expect(globalThis.document.body.insertBefore).not.toHaveBeenCalled();
    });

    it("skips handling the mutation if excessive mutations are being triggered", () => {
      jest
        .spyOn(
          autofillOverlayContentService as any,
          "isTriggeringExcessiveMutationObserverIterations"
        )
        .mockReturnValue(true);

      autofillOverlayContentService["handleBodyElementMutationObserverUpdate"]();

      expect(globalThis.document.body.insertBefore).not.toHaveBeenCalled();
    });

    it("skips re-arranging the DOM elements if the last child of the body is the overlay list and the second to last child of the body is the overlay button", () => {
      autofillOverlayContentService["handleBodyElementMutationObserverUpdate"]();

      expect(globalThis.document.body.insertBefore).not.toHaveBeenCalled();
    });

    it("skips re-arranging the DOM elements if the last child is the overlay button and the overlay list is not visible", () => {
      overlayListElement.remove();
      autofillOverlayContentService["isOverlayListVisible"] = false;

      autofillOverlayContentService["handleBodyElementMutationObserverUpdate"]();

      expect(globalThis.document.body.insertBefore).not.toHaveBeenCalled();
    });

    it("positions the overlay button before the overlay list if an element has inserted itself after the button element", () => {
      const injectedElement = document.createElement("div");
      document.body.insertBefore(injectedElement, overlayListElement);

      autofillOverlayContentService["handleBodyElementMutationObserverUpdate"]();

      expect(globalThis.document.body.insertBefore).toHaveBeenCalledWith(
        overlayButtonElement,
        overlayListElement
      );
    });

    it("positions the overlay button before the overlay list if the elements have inserted in incorrect order", () => {
      document.body.appendChild(overlayButtonElement);

      autofillOverlayContentService["handleBodyElementMutationObserverUpdate"]();

      expect(globalThis.document.body.insertBefore).toHaveBeenCalledWith(
        overlayButtonElement,
        overlayListElement
      );
    });

    it("positions the last child before the overlay button if it is not the overlay list", () => {
      const injectedElement = document.createElement("div");
      document.body.appendChild(injectedElement);

      autofillOverlayContentService["handleBodyElementMutationObserverUpdate"]();

      expect(globalThis.document.body.insertBefore).toHaveBeenCalledWith(
        injectedElement,
        overlayButtonElement
      );
    });
  });

  describe("handleDocumentElementMutationObserverUpdate", () => {
    let overlayButtonElement: HTMLElement;
    let overlayListElement: HTMLElement;

    beforeEach(() => {
      document.body.innerHTML = `
      <div class="overlay-button"></div>
      <div class="overlay-list"></div>
      `;
      document.head.innerHTML = `<title>test</title>`;
      overlayButtonElement = document.querySelector(".overlay-button") as HTMLElement;
      overlayListElement = document.querySelector(".overlay-list") as HTMLElement;
      autofillOverlayContentService["overlayButtonElement"] = overlayButtonElement;
      autofillOverlayContentService["overlayListElement"] = overlayListElement;
      autofillOverlayContentService["isOverlayListVisible"] = true;
      jest.spyOn(globalThis.document.body, "appendChild");
      jest
        .spyOn(
          autofillOverlayContentService as any,
          "isTriggeringExcessiveMutationObserverIterations"
        )
        .mockReturnValue(false);
    });

    it("skips modification of the DOM if the overlay button and list elements are not present", () => {
      autofillOverlayContentService["overlayButtonElement"] = undefined;
      autofillOverlayContentService["overlayListElement"] = undefined;

      autofillOverlayContentService["handleDocumentElementMutationObserverUpdate"]([
        mock<MutationRecord>(),
      ]);

      expect(globalThis.document.body.appendChild).not.toHaveBeenCalled();
    });

    it("skips modification of the DOM if excessive mutation events are being triggered", () => {
      jest
        .spyOn(
          autofillOverlayContentService as any,
          "isTriggeringExcessiveMutationObserverIterations"
        )
        .mockReturnValue(true);

      autofillOverlayContentService["handleDocumentElementMutationObserverUpdate"]([
        mock<MutationRecord>(),
      ]);

      expect(globalThis.document.body.appendChild).not.toHaveBeenCalled();
    });

    it("ignores the mutation record if the record is not of type `childlist`", () => {
      autofillOverlayContentService["handleDocumentElementMutationObserverUpdate"]([
        mock<MutationRecord>({
          type: "attributes",
        }),
      ]);

      expect(globalThis.document.body.appendChild).not.toHaveBeenCalled();
    });

    it("ignores the mutation record if the record does not contain any added nodes", () => {
      autofillOverlayContentService["handleDocumentElementMutationObserverUpdate"]([
        mock<MutationRecord>({
          type: "childList",
          addedNodes: mock<NodeList>({ length: 0 }),
        }),
      ]);

      expect(globalThis.document.body.appendChild).not.toHaveBeenCalled();
    });

    it("ignores mutations for the document body and head", () => {
      autofillOverlayContentService["handleDocumentElementMutationObserverUpdate"]([
        {
          type: "childList",
          addedNodes: document.querySelectorAll("body, head"),
        } as unknown as MutationRecord,
      ]);

      expect(globalThis.document.body.appendChild).not.toHaveBeenCalled();
    });

    it("appends the identified node to the body", async () => {
      jest.useFakeTimers();
      const injectedElement = document.createElement("div");
      injectedElement.id = "test";
      document.documentElement.appendChild(injectedElement);
      autofillOverlayContentService["handleDocumentElementMutationObserverUpdate"]([
        {
          type: "childList",
          addedNodes: document.querySelectorAll("#test"),
        } as unknown as MutationRecord,
      ]);
      jest.advanceTimersByTime(10);

      expect(globalThis.document.body.appendChild).toHaveBeenCalledWith(injectedElement);
    });
  });

  describe("isTriggeringExcessiveMutationObserverIterations", () => {
    it("clears any existing reset timeout", () => {
      jest.useFakeTimers();
      const clearTimeoutSpy = jest.spyOn(globalThis, "clearTimeout");
      autofillOverlayContentService["mutationObserverIterationsResetTimeout"] = setTimeout(
        jest.fn(),
        123
      );

      autofillOverlayContentService["isTriggeringExcessiveMutationObserverIterations"]();

      expect(clearTimeoutSpy).toHaveBeenCalledWith(expect.anything());
    });

    it("will reset the number of mutationObserverIterations after two seconds", () => {
      jest.useFakeTimers();
      autofillOverlayContentService["mutationObserverIterations"] = 10;

      autofillOverlayContentService["isTriggeringExcessiveMutationObserverIterations"]();
      jest.advanceTimersByTime(2000);

      expect(autofillOverlayContentService["mutationObserverIterations"]).toEqual(0);
    });

    it("will blur the overlay field and remove the autofill overlay if excessive mutation observer iterations are triggering", async () => {
      autofillOverlayContentService["mutationObserverIterations"] = 101;
      const blurMostRecentOverlayFieldSpy = jest.spyOn(
        autofillOverlayContentService as any,
        "blurMostRecentOverlayField"
      );
      const removeAutofillOverlaySpy = jest.spyOn(
        autofillOverlayContentService as any,
        "removeAutofillOverlay"
      );

      autofillOverlayContentService["isTriggeringExcessiveMutationObserverIterations"]();
      await flushPromises();

      expect(blurMostRecentOverlayFieldSpy).toHaveBeenCalled();
      expect(removeAutofillOverlaySpy).toHaveBeenCalled();
    });
  });

  describe("handleVisibilityChangeEvent", () => {
    it("skips removing the overlay if the document is visible", () => {
      jest.spyOn(autofillOverlayContentService as any, "removeAutofillOverlay");

      autofillOverlayContentService["handleVisibilityChangeEvent"]();

      expect(autofillOverlayContentService["removeAutofillOverlay"]).not.toHaveBeenCalled();
    });

    it("removes the overlay if the document is not visible", () => {
      Object.defineProperty(document, "visibilityState", {
        value: "hidden",
        writable: true,
      });
      jest.spyOn(autofillOverlayContentService as any, "removeAutofillOverlay");

      autofillOverlayContentService["handleVisibilityChangeEvent"]();

      expect(autofillOverlayContentService["removeAutofillOverlay"]).toHaveBeenCalled();
    });
  });
});