Rework UrlPreviewSettings to use MatrixClient.CryptoApi.isEncryptionEnabledInRoom

src/components/views/room_settings/UrlPreviewSettings.tsx

@@ -9,107 +9,140 @@ SPDX-License-Identifier: AGPL-3.0-only OR GPL-3.0-only
 Please see LICENSE files in the repository root for full details.
 */
 
-import React, { ReactNode } from "react";
+import React, { ReactNode, JSX } from "react";
 import { Room } from "matrix-js-sdk/src/matrix";
 
-import { _t, _td } from "../../../languageHandler";
+import { _t } from "../../../languageHandler";
 import SettingsStore from "../../../settings/SettingsStore";
 import dis from "../../../dispatcher/dispatcher";
-import { MatrixClientPeg } from "../../../MatrixClientPeg";
 import { Action } from "../../../dispatcher/actions";
 import { SettingLevel } from "../../../settings/SettingLevel";
 import SettingsFlag from "../elements/SettingsFlag";
 import SettingsFieldset from "../settings/SettingsFieldset";
 import AccessibleButton, { ButtonEvent } from "../elements/AccessibleButton";
+import { useIsEncrypted } from "../../../hooks/useIsEncrypted.ts";
+import { useMatrixClientContext } from "../../../contexts/MatrixClientContext.tsx";
+import { useSettingValueAt } from "../../../hooks/useSettings.ts";
 
-interface IProps {
+/**
+ * The URL preview settings for a room
+ */
+interface UrlPreviewSettingsProps {
+    /**
+     * The room.
+     */
     room: Room;
 }
 
-export default class UrlPreviewSettings extends React.Component<IProps> {
-    private onClickUserSettings = (e: ButtonEvent): void => {
-        e.preventDefault();
-        e.stopPropagation();
-        dis.fire(Action.ViewUserSettings);
-    };
-
-    public render(): ReactNode {
-        const roomId = this.props.room.roomId;
-        const isEncrypted = MatrixClientPeg.safeGet().isRoomEncrypted(roomId);
-
-        let previewsForAccount: ReactNode | undefined;
-        let previewsForRoom: ReactNode | undefined;
-
-        if (!isEncrypted) {
-            // Only show account setting state and room state setting state in non-e2ee rooms where they apply
-            const accountEnabled = SettingsStore.getValueAt(SettingLevel.ACCOUNT, "urlPreviewsEnabled");
-            if (accountEnabled) {
-                previewsForAccount = _t(
-                    "room_settings|general|user_url_previews_default_on",
-                    {},
-                    {
-                        a: (sub) => (
-                            <AccessibleButton kind="link_inline" onClick={this.onClickUserSettings}>
-                                {sub}
-                            </AccessibleButton>
-                        ),
-                    },
-                );
-            } else {
-                previewsForAccount = _t(
-                    "room_settings|general|user_url_previews_default_off",
-                    {},
-                    {
-                        a: (sub) => (
-                            <AccessibleButton kind="link_inline" onClick={this.onClickUserSettings}>
-                                {sub}
-                            </AccessibleButton>
-                        ),
-                    },
-                );
-            }
-
-            if (SettingsStore.canSetValue("urlPreviewsEnabled", roomId, SettingLevel.ROOM)) {
-                previewsForRoom = (
-                    <SettingsFlag
-                        name="urlPreviewsEnabled"
-                        level={SettingLevel.ROOM}
-                        roomId={roomId}
-                        isExplicit={true}
-                    />
-                );
-            } else {
-                let str = _td("room_settings|general|default_url_previews_on");
-                if (!SettingsStore.getValueAt(SettingLevel.ROOM, "urlPreviewsEnabled", roomId, /*explicit=*/ true)) {
-                    str = _td("room_settings|general|default_url_previews_off");
-                }
-                previewsForRoom = <div>{_t(str)}</div>;
-            }
-        } else {
-            previewsForAccount = _t("room_settings|general|url_preview_encryption_warning");
-        }
-
-        const previewsForRoomAccount = // in an e2ee room we use a special key to enforce per-room opt-in
-            (
-                <SettingsFlag
-                    name={isEncrypted ? "urlPreviewsEnabled_e2ee" : "urlPreviewsEnabled"}
-                    level={SettingLevel.ROOM_DEVICE}
-                    roomId={roomId}
-                />
-            );
-
-        const description = (
-            <>
-                <p>{_t("room_settings|general|url_preview_explainer")}</p>
-                <p>{previewsForAccount}</p>
-            </>
+export function UrlPreviewSettings({ room }: UrlPreviewSettingsProps): JSX.Element {
+    const { roomId } = room;
+    const matrixClient = useMatrixClientContext();
+    const isEncrypted = Boolean(useIsEncrypted(matrixClient, room));
+    const previewsForRoomAccount = // in an e2ee room we use a special key to enforce per-room opt-in
+        (
+            <SettingsFlag
+                name={isEncrypted ? "urlPreviewsEnabled_e2ee" : "urlPreviewsEnabled"}
+                level={SettingLevel.ROOM_DEVICE}
+                roomId={roomId}
+            />
         );
 
-        return (
-            <SettingsFieldset legend={_t("room_settings|general|url_previews_section")} description={description}>
-                {previewsForRoom}
-                {previewsForRoomAccount}
-            </SettingsFieldset>
+    return (
+        <SettingsFieldset
+            legend={_t("room_settings|general|url_previews_section")}
+            description={<Description isEncrypted={isEncrypted} />}
+        >
+            <PreviewsForRoom isEncrypted={isEncrypted} roomId={roomId} />
+            {previewsForRoomAccount}
+        </SettingsFieldset>
+    );
+}
+
+/**
+ * Click handler for the user settings link
+ * @param e
+ */
+function onClickUserSettings(e: ButtonEvent): void {
+    e.preventDefault();
+    e.stopPropagation();
+    dis.fire(Action.ViewUserSettings);
+}
+
+/**
+ * The description for the URL preview settings
+ */
+interface DescriptionProps {
+    /**
+     * Whether the room is encrypted
+     */
+    isEncrypted: boolean;
+}
+
+function Description({ isEncrypted }: DescriptionProps): JSX.Element {
+    const urlPreviewsEnabled = useSettingValueAt(SettingLevel.ACCOUNT, "urlPreviewsEnabled");
+
+    let previewsForAccount: ReactNode | undefined;
+    if (isEncrypted) {
+        previewsForAccount = _t("room_settings|general|url_preview_encryption_warning");
+    } else {
+        const button = {
+            a: (sub: string) => (
+                <AccessibleButton kind="link_inline" onClick={onClickUserSettings}>
+                    {sub}
+                </AccessibleButton>
+            ),
+        };
+
+        previewsForAccount = urlPreviewsEnabled
+            ? _t("room_settings|general|user_url_previews_default_on", {}, button)
+            : _t("room_settings|general|user_url_previews_default_off", {}, button);
+    }
+
+    return (
+        <>
+            <p>{_t("room_settings|general|url_preview_explainer")}</p>
+            <p>{previewsForAccount}</p>
+        </>
+    );
+}
+
+/**
+ * The description for the URL preview settings
+ */
+interface PreviewsForRoomProps {
+    /**
+     * Whether the room is encrypted
+     */
+    isEncrypted: boolean;
+    /**
+     * The room ID
+     */
+    roomId: string;
+}
+
+function PreviewsForRoom({ isEncrypted, roomId }: PreviewsForRoomProps): JSX.Element | null {
+    const urlPreviewsEnabled = useSettingValueAt(
+        SettingLevel.ACCOUNT,
+        "urlPreviewsEnabled",
+        roomId,
+        /*explicit=*/ true,
+    );
+    if (isEncrypted) return null;
+
+    let previewsForRoom: ReactNode;
+    if (SettingsStore.canSetValue("urlPreviewsEnabled", roomId, SettingLevel.ROOM)) {
+        previewsForRoom = (
+            <SettingsFlag name="urlPreviewsEnabled" level={SettingLevel.ROOM} roomId={roomId} isExplicit={true} />
+        );
+    } else {
+        previewsForRoom = (
+            <div>
+                {urlPreviewsEnabled
+                    ? _t("room_settings|general|default_url_previews_on")
+                    : _t("room_settings|general|default_url_previews_off")}
+            </div>
         );
     }
+
+    return previewsForRoom;
 }

src/components/views/settings/tabs/room/GeneralRoomSettingsTab.tsx

@@ -16,12 +16,12 @@ import dis from "../../../../../dispatcher/dispatcher";
 import MatrixClientContext from "../../../../../contexts/MatrixClientContext";
 import SettingsStore from "../../../../../settings/SettingsStore";
 import { UIFeature } from "../../../../../settings/UIFeature";
-import UrlPreviewSettings from "../../../room_settings/UrlPreviewSettings";
 import AliasSettings from "../../../room_settings/AliasSettings";
 import PosthogTrackers from "../../../../../PosthogTrackers";
 import { SettingsSubsection } from "../../shared/SettingsSubsection";
 import SettingsTab from "../SettingsTab";
 import { SettingsSection } from "../../shared/SettingsSection";
+import { UrlPreviewSettings } from "../../../room_settings/UrlPreviewSettings";
 
 interface IProps {
     room: Room;

test/unit-tests/components/views/room_settings/UrlPreviewSettings-test.tsx

@@ -0,0 +1,82 @@
+/*
+ * Copyright 2024 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR GPL-3.0-only
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+import React from "react";
+import { MatrixClient, Room } from "matrix-js-sdk/src/matrix";
+import { render, screen } from "jest-matrix-react";
+import { waitFor } from "@testing-library/dom";
+
+import { createTestClient, mkStubRoom, withClientContextRenderOptions } from "../../../../test-utils";
+import { UrlPreviewSettings } from "../../../../../src/components/views/room_settings/UrlPreviewSettings.tsx";
+import SettingsStore from "../../../../../src/settings/SettingsStore.ts";
+import dis from "../../../../../src/dispatcher/dispatcher.ts";
+import { Action } from "../../../../../src/dispatcher/actions.ts";
+
+describe("UrlPreviewSettings", () => {
+    let client: MatrixClient;
+    let room: Room;
+
+    beforeEach(() => {
+        client = createTestClient();
+        room = mkStubRoom("roomId", "room", client);
+    });
+
+    afterEach(() => {
+        jest.restoreAllMocks();
+    });
+
+    function renderComponent() {
+        return render(<UrlPreviewSettings room={room} />, withClientContextRenderOptions(client));
+    }
+
+    it("should display the correct preview when the room is encrypted and the url preview is enabled", async () => {
+        jest.spyOn(client.getCrypto()!, "isEncryptionEnabledInRoom").mockResolvedValue(true);
+        jest.spyOn(SettingsStore, "getValue").mockReturnValue(true);
+
+        const { asFragment } = renderComponent();
+        await waitFor(() => {
+            expect(
+                screen.getByText(
+                    "In encrypted rooms, like this one, URL previews are disabled by default to ensure that your homeserver (where the previews are generated) cannot gather information about links you see in this room.",
+                ),
+            ).toBeInTheDocument();
+        });
+        expect(asFragment()).toMatchSnapshot();
+    });
+
+    it("should display the correct preview when the room is unencrypted and the url preview is enabled", async () => {
+        jest.spyOn(client.getCrypto()!, "isEncryptionEnabledInRoom").mockResolvedValue(false);
+        jest.spyOn(SettingsStore, "getValueAt").mockReturnValue(true);
+        jest.spyOn(dis, "fire").mockReturnValue(undefined);
+
+        const { asFragment } = renderComponent();
+        await waitFor(() => {
+            expect(screen.getByRole("button", { name: "enabled" })).toBeInTheDocument();
+            expect(
+                screen.getByText("URL previews are enabled by default for participants in this room."),
+            ).toBeInTheDocument();
+        });
+        expect(asFragment()).toMatchSnapshot();
+
+        screen.getByRole("button", { name: "enabled" }).click();
+        expect(dis.fire).toHaveBeenCalledWith(Action.ViewUserSettings);
+    });
+
+    it("should display the correct preview when the room is unencrypted and the url preview is disabled", async () => {
+        jest.spyOn(client.getCrypto()!, "isEncryptionEnabledInRoom").mockResolvedValue(false);
+        jest.spyOn(SettingsStore, "getValueAt").mockReturnValue(false);
+
+        const { asFragment } = renderComponent();
+        await waitFor(() => {
+            expect(screen.getByRole("button", { name: "disabled" })).toBeInTheDocument();
+            expect(
+                screen.getByText("URL previews are disabled by default for participants in this room."),
+            ).toBeInTheDocument();
+        });
+        expect(asFragment()).toMatchSnapshot();
+    });
+});