refactor(chat): remove keyboard compatibility layer

src/app/chat/components/chat-input-bar.module.css

@@ -1,14 +1,11 @@
 /* ChatInputBar 输入栏容器样式（与 Dart chat_input_bar.dart 对齐） */
 
-/* 键盘适配：--chat-input-lift 仅写入当前聊天输入栏。 */
-
 .bar {
   flex: 0 0 auto;
   padding: 0
     calc(var(--chat-inline-padding, 16px) + var(--app-safe-right, 0px))
     calc(
-      var(--spacing-lg, 16px) + var(--chat-input-lift, 0px) +
+      var(--spacing-lg, 16px) + var(--app-safe-bottom, 0px)
-        var(--app-safe-bottom, 0px)
     )
     calc(var(--chat-inline-padding, 16px) + var(--app-safe-left, 0px));
   background: transparent;

src/app/chat/components/chat-input-bar.tsx

@@ -4,7 +4,7 @@ import { useRef, useState } from "react";
 import { useChatDispatch } from "@/stores/chat/chat-context";
 import { Logger } from "@/utils/logger";
 
-import { useChatKeyboardAvoidance } from "../hooks/use-chat-keyboard-avoidance";
+import { useChatKeyboardDiagnostics } from "../hooks/use-chat-keyboard-diagnostics";
 import { ChatInputTextField } from "./chat-input-text-field";
 import { ChatSendButton } from "./chat-send-button";
 import styles from "./chat-input-bar.module.css";
@@ -26,10 +26,7 @@ export function ChatInputBar({ disabled = false }: ChatInputBarProps) {
 
   const hasContent = input.trim().length > 0;
 
-  useChatKeyboardAvoidance({
+  useChatKeyboardDiagnostics({ containerRef: barRef });
-    containerRef: barRef,
-    active: isFocused,
-  });
 
   const handleInputChange = (value: string) => {
     setInput(value);

src/app/chat/hooks/__tests__/chat-keyboard-geometry.test.ts

@@ -1,90 +0,0 @@
-import { describe, expect, it } from "vitest";
-
-import {
-  resolveChatKeyboardFallbackLift,
-  resolveChatKeyboardLift,
-  type ChatKeyboardViewportBaseline,
-  type ChatKeyboardViewportSnapshot,
-} from "../chat-keyboard-geometry";
-
-const baseline: ChatKeyboardViewportBaseline = {
-  layoutHeight: 800,
-  visualHeight: 760,
-};
-
-function makeSnapshot(
-  overrides: Partial<ChatKeyboardViewportSnapshot> = {},
-): ChatKeyboardViewportSnapshot {
-  return {
-    layoutHeight: 800,
-    visualHeight: 760,
-    visualScale: 1,
-    virtualKeyboardHeight: 0,
-    ...overrides,
-  };
-}
-
-describe("resolveChatKeyboardLift", () => {
-  it("does not add lift when the content viewport already resized", () => {
-    expect(
-      resolveChatKeyboardLift(
-        baseline,
-        makeSnapshot({ layoutHeight: 500, visualHeight: 500 }),
-      ),
-    ).toEqual({
-      keyboardVisible: true,
-      lift: 0,
-      source: "content-resize",
-    });
-  });
-
-  it("uses the visual viewport delta for an overlay keyboard", () => {
-    expect(
-      resolveChatKeyboardLift(
-        baseline,
-        makeSnapshot({ visualHeight: 460 }),
-      ),
-    ).toEqual({
-      keyboardVisible: true,
-      lift: 314,
-      source: "visual-viewport",
-    });
-  });
-
-  it("prefers Virtual Keyboard geometry when available", () => {
-    expect(
-      resolveChatKeyboardLift(
-        baseline,
-        makeSnapshot({
-          visualHeight: 520,
-          virtualKeyboardHeight: 320,
-        }),
-      ),
-    ).toEqual({
-      keyboardVisible: true,
-      lift: 334,
-      source: "virtual-keyboard",
-    });
-  });
-
-  it("ignores visual viewport changes caused by page zoom", () => {
-    expect(
-      resolveChatKeyboardLift(
-        baseline,
-        makeSnapshot({ visualHeight: 460, visualScale: 1.2 }),
-      ),
-    ).toEqual({
-      keyboardVisible: false,
-      lift: 0,
-      source: "none",
-    });
-  });
-});
-
-describe("resolveChatKeyboardFallbackLift", () => {
-  it("scales with viewport height and remains bounded", () => {
-    expect(resolveChatKeyboardFallbackLift(500)).toBe(260);
-    expect(resolveChatKeyboardFallbackLift(800)).toBe(336);
-    expect(resolveChatKeyboardFallbackLift(1_200)).toBe(380);
-  });
-});

src/app/chat/hooks/__tests__/use-chat-keyboard-avoidance.test.tsx

@@ -1,178 +0,0 @@
-/* @vitest-environment jsdom */
-
-import { act, useRef } from "react";
-import { createRoot, type Root } from "react-dom/client";
-import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
-
-import { BrowserDetector } from "@/utils/browser-detect";
-
-import { useChatKeyboardAvoidance } from "../use-chat-keyboard-avoidance";
-
-vi.mock("@/utils/browser-detect", () => ({
-  BrowserDetector: {
-    isInAppBrowser: vi.fn(() => true),
-  },
-}));
-
-vi.mock("@/utils/platform-detect", () => ({
-  PlatformDetector: {
-    isAndroid: vi.fn(() => true),
-  },
-}));
-
-class MockVisualViewport extends EventTarget {
-  height = 760;
-  offsetTop = 0;
-  scale = 1;
-  width = 390;
-}
-
-function Harness({ active }: { active: boolean }) {
-  const containerRef = useRef<HTMLDivElement>(null);
-  useChatKeyboardAvoidance({ active, containerRef });
-  return <div ref={containerRef} data-testid="chat-input" />;
-}
-
-describe("useChatKeyboardAvoidance", () => {
-  let container: HTMLDivElement;
-  let root: Root;
-  let visualViewport: MockVisualViewport;
-  let innerHeight: number;
-
-  beforeEach(() => {
-    vi.useFakeTimers();
-    (globalThis as { IS_REACT_ACT_ENVIRONMENT?: boolean })
-      .IS_REACT_ACT_ENVIRONMENT = true;
-    vi.mocked(BrowserDetector.isInAppBrowser).mockReturnValue(true);
-    innerHeight = 800;
-    visualViewport = new MockVisualViewport();
-    Object.defineProperty(window, "innerHeight", {
-      configurable: true,
-      get: () => innerHeight,
-    });
-    Object.defineProperty(window, "visualViewport", {
-      configurable: true,
-      value: visualViewport,
-    });
-    vi.stubGlobal(
-      "requestAnimationFrame",
-      vi.fn((callback: FrameRequestCallback) =>
-        window.setTimeout(() => callback(0), 0),
-      ),
-    );
-    vi.stubGlobal(
-      "cancelAnimationFrame",
-      vi.fn((id: number) => window.clearTimeout(id)),
-    );
-    container = document.createElement("div");
-    document.body.append(container);
-    root = createRoot(container);
-  });
-
-  afterEach(() => {
-    act(() => root.unmount());
-    container.remove();
-    vi.useRealTimers();
-    vi.restoreAllMocks();
-    vi.unstubAllGlobals();
-  });
-
-  it("uses a one-shot adaptive fallback without polling", () => {
-    const intervalSpy = vi.spyOn(window, "setInterval");
-    renderHarness(root, false);
-    renderHarness(root, true);
-
-    act(() => vi.advanceTimersByTime(350));
-
-    expect(getInput(container).style.getPropertyValue("--chat-input-lift")).toBe(
-      "336px",
-    );
-    expect(intervalSpy).not.toHaveBeenCalled();
-  });
-
-  it("does not use the fallback in a regular Android browser", () => {
-    vi.mocked(BrowserDetector.isInAppBrowser).mockReturnValue(false);
-    renderHarness(root, false);
-    renderHarness(root, true);
-
-    act(() => vi.advanceTimersByTime(350));
-
-    expect(getInput(container).style.getPropertyValue("--chat-input-lift")).toBe(
-      "",
-    );
-  });
-
-  it("uses Visual Viewport geometry and clears after keyboard dismissal", () => {
-    renderHarness(root, false);
-    renderHarness(root, true);
-
-    visualViewport.height = 460;
-    act(() => {
-      visualViewport.dispatchEvent(new Event("resize"));
-      vi.runOnlyPendingTimers();
-    });
-    expect(getInput(container).style.getPropertyValue("--chat-input-lift")).toBe(
-      "314px",
-    );
-
-    visualViewport.height = 760;
-    act(() => {
-      visualViewport.dispatchEvent(new Event("resize"));
-      vi.runOnlyPendingTimers();
-    });
-    expect(getInput(container).style.getPropertyValue("--chat-input-lift")).toBe(
-      "0px",
-    );
-
-    act(() => vi.advanceTimersByTime(1_000));
-    expect(getInput(container).style.getPropertyValue("--chat-input-lift")).toBe(
-      "0px",
-    );
-  });
-
-  it("does not add fallback lift when the layout viewport resized", () => {
-    renderHarness(root, false);
-    renderHarness(root, true);
-
-    innerHeight = 500;
-    visualViewport.height = 500;
-    act(() => {
-      window.dispatchEvent(new Event("resize"));
-      vi.advanceTimersByTime(350);
-    });
-
-    expect(getInput(container).style.getPropertyValue("--chat-input-lift")).toBe(
-      "0px",
-    );
-  });
-
-  it("removes the local lift when focus leaves or the hook unmounts", () => {
-    renderHarness(root, false);
-    renderHarness(root, true);
-    act(() => vi.advanceTimersByTime(350));
-    expect(getInput(container).style.getPropertyValue("--chat-input-lift")).toBe(
-      "336px",
-    );
-
-    renderHarness(root, false);
-    expect(getInput(container).style.getPropertyValue("--chat-input-lift")).toBe(
-      "",
-    );
-
-    act(() => root.unmount());
-    expect(container.querySelector('[data-testid="chat-input"]')).toBeNull();
-    root = createRoot(container);
-  });
-});
-
-function renderHarness(root: Root, active: boolean): void {
-  act(() => root.render(<Harness active={active} />));
-}
-
-function getInput(container: HTMLElement): HTMLDivElement {
-  const input = container.querySelector<HTMLDivElement>(
-    '[data-testid="chat-input"]',
-  );
-  if (!input) throw new Error("Chat input test node was not rendered");
-  return input;
-}

src/app/chat/hooks/__tests__/use-chat-keyboard-diagnostics.test.tsx

@@ -68,6 +68,8 @@ describe("chat keyboard diagnostics", () => {
 
   afterEach(() => {
     window.__keyboardDebugCleanup?.();
+    document.documentElement.style.removeProperty("--app-viewport-height");
+    document.documentElement.style.removeProperty("--app-visible-height");
     vi.restoreAllMocks();
   });
 
@@ -79,7 +81,8 @@ describe("chat keyboard diagnostics", () => {
 
   it("records viewport events and exposes manual snapshot helpers", () => {
     const input = document.createElement("textarea");
-    input.style.setProperty("--chat-input-lift", "314px");
+    document.documentElement.style.setProperty("--app-viewport-height", "800px");
+    document.documentElement.style.setProperty("--app-visible-height", "460px");
     document.body.append(input);
     input.focus();
     const inputRef = { current: input } as RefObject<HTMLElement | null>;
@@ -96,7 +99,10 @@ describe("chat keyboard diagnostics", () => {
       virtualKeyboardRect: { height: 300 },
       activeElement: "TEXTAREA",
       activeFocused: true,
-      inputLift: "314px",
+      inputBarTop: 0,
+      inputBarBottom: 0,
+      appViewportHeight: "800px",
+      appVisibleHeight: "460px",
       platform: { name: "android", deviceModel: "PLB110" },
       browser: { inAppBrowserName: "facebook" },
     });

src/app/chat/hooks/chat-keyboard-geometry.ts

@@ -1,95 +0,0 @@
-export const CHAT_KEYBOARD_FOCUS_GAP_PX = 14;
-export const CHAT_KEYBOARD_VISIBLE_THRESHOLD_PX = 80;
-export const CHAT_KEYBOARD_ZOOM_THRESHOLD = 1.05;
-export const CHAT_KEYBOARD_FALLBACK_RATIO = 0.42;
-export const CHAT_KEYBOARD_FALLBACK_MIN_PX = 260;
-export const CHAT_KEYBOARD_FALLBACK_MAX_PX = 380;
-
-const CHAT_KEYBOARD_MAX_LIFT_RATIO = 0.55;
-
-export interface ChatKeyboardViewportBaseline {
-  layoutHeight: number;
-  visualHeight: number;
-}
-
-export interface ChatKeyboardViewportSnapshot {
-  layoutHeight: number;
-  visualHeight: number;
-  visualScale: number;
-  virtualKeyboardHeight: number;
-}
-
-export type ChatKeyboardLiftSource =
-  | "content-resize"
-  | "visual-viewport"
-  | "virtual-keyboard"
-  | "none";
-
-export interface ChatKeyboardLiftResolution {
-  keyboardVisible: boolean;
-  lift: number;
-  source: ChatKeyboardLiftSource;
-}
-
-export function resolveChatKeyboardLift(
-  baseline: ChatKeyboardViewportBaseline,
-  snapshot: ChatKeyboardViewportSnapshot,
-): ChatKeyboardLiftResolution {
-  const contentResize = baseline.layoutHeight - snapshot.layoutHeight;
-  if (contentResize > CHAT_KEYBOARD_VISIBLE_THRESHOLD_PX) {
-    return {
-      keyboardVisible: true,
-      lift: 0,
-      source: "content-resize",
-    };
-  }
-
-  const virtualKeyboardHeight = Math.max(
-    0,
-    snapshot.virtualKeyboardHeight,
-  );
-  const visualViewportHeight =
-    snapshot.visualScale <= CHAT_KEYBOARD_ZOOM_THRESHOLD
-      ? Math.max(0, baseline.visualHeight - snapshot.visualHeight)
-      : 0;
-  const occludedHeight = Math.max(
-    virtualKeyboardHeight,
-    visualViewportHeight,
-  );
-
-  if (occludedHeight <= CHAT_KEYBOARD_VISIBLE_THRESHOLD_PX) {
-    return {
-      keyboardVisible: false,
-      lift: 0,
-      source: "none",
-    };
-  }
-
-  const maxLift = Math.round(
-    baseline.layoutHeight * CHAT_KEYBOARD_MAX_LIFT_RATIO,
-  );
-
-  return {
-    keyboardVisible: true,
-    lift: Math.min(
-      maxLift,
-      Math.round(occludedHeight + CHAT_KEYBOARD_FOCUS_GAP_PX),
-    ),
-    source:
-      virtualKeyboardHeight >= visualViewportHeight
-        ? "virtual-keyboard"
-        : "visual-viewport",
-  };
-}
-
-export function resolveChatKeyboardFallbackLift(
-  layoutHeight: number,
-): number {
-  return Math.min(
-    CHAT_KEYBOARD_FALLBACK_MAX_PX,
-    Math.max(
-      CHAT_KEYBOARD_FALLBACK_MIN_PX,
-      Math.round(layoutHeight * CHAT_KEYBOARD_FALLBACK_RATIO),
-    ),
-  );
-}

src/app/chat/hooks/use-chat-keyboard-avoidance.ts

@@ -1,246 +0,0 @@
-"use client";
-
-import { useEffect, useRef, type RefObject } from "react";
-
-import { BrowserDetector } from "@/utils/browser-detect";
-import { Logger } from "@/utils/logger";
-import { PlatformDetector } from "@/utils/platform-detect";
-
-import {
-  resolveChatKeyboardFallbackLift,
-  resolveChatKeyboardLift,
-  type ChatKeyboardLiftResolution,
-  type ChatKeyboardViewportBaseline,
-  type ChatKeyboardViewportSnapshot,
-} from "./chat-keyboard-geometry";
-import { useChatKeyboardDiagnostics } from "./use-chat-keyboard-diagnostics";
-
-const CHAT_INPUT_LIFT_VAR = "--chat-input-lift";
-const CHAT_KEYBOARD_FALLBACK_DELAY_MS = 350;
-
-const log = new Logger("UseChatKeyboardAvoidance");
-
-interface VirtualKeyboardLike extends EventTarget {
-  readonly boundingRect?: Pick<DOMRectReadOnly, "height">;
-}
-
-interface NavigatorWithVirtualKeyboard extends Navigator {
-  readonly virtualKeyboard?: VirtualKeyboardLike;
-}
-
-export interface UseChatKeyboardAvoidanceOptions {
-  active: boolean;
-  containerRef: RefObject<HTMLElement | null>;
-}
-
-export function useChatKeyboardAvoidance({
-  active,
-  containerRef,
-}: UseChatKeyboardAvoidanceOptions): void {
-  const activeRef = useRef(active);
-  const baselineRef = useRef<ChatKeyboardViewportBaseline | null>(null);
-
-  useChatKeyboardDiagnostics({ containerRef });
-
-  useEffect(() => {
-    activeRef.current = active;
-  }, [active]);
-
-  useEffect(() => {
-    if (typeof window === "undefined" || !PlatformDetector.isAndroid()) {
-      return;
-    }
-
-    const updateBaseline = () => {
-      if (activeRef.current) return;
-      baselineRef.current = readViewportBaseline();
-    };
-    const visualViewport = window.visualViewport;
-
-    updateBaseline();
-    window.addEventListener("resize", updateBaseline);
-    window.addEventListener("orientationchange", updateBaseline);
-    visualViewport?.addEventListener("resize", updateBaseline);
-    visualViewport?.addEventListener("scroll", updateBaseline);
-
-    return () => {
-      window.removeEventListener("resize", updateBaseline);
-      window.removeEventListener("orientationchange", updateBaseline);
-      visualViewport?.removeEventListener("resize", updateBaseline);
-      visualViewport?.removeEventListener("scroll", updateBaseline);
-    };
-  }, []);
-
-  useEffect(() => {
-    const container = containerRef.current;
-    if (typeof window === "undefined" || !container) return;
-
-    if (!active || !PlatformDetector.isAndroid()) {
-      clearInputLift(container);
-      if (!active) baselineRef.current = readViewportBaseline();
-      return;
-    }
-
-    const baseline = baselineRef.current ?? readViewportBaseline();
-    const visualViewport = window.visualViewport;
-    const virtualKeyboard = getVirtualKeyboard();
-    const fallbackAllowed = BrowserDetector.isInAppBrowser();
-    let frameId: number | null = null;
-    let fallbackTimerId: number | null = null;
-    let lastLift = -1;
-    let pendingCanDismiss = false;
-    let pendingReason = "initial";
-    let keyboardObserved = false;
-    let fallbackApplied = false;
-    let sessionDismissed = false;
-
-    const applyLift = (
-      lift: number,
-      source: ChatKeyboardLiftResolution["source"] | "fallback" | "reset",
-    ) => {
-      const nextLift = Math.max(0, Math.round(lift));
-      if (nextLift === lastLift) return;
-      lastLift = nextLift;
-      container.style.setProperty(CHAT_INPUT_LIFT_VAR, `${nextLift}px`);
-      log.debug("[chat-keyboard] apply", {
-        source,
-        lift: nextLift,
-      });
-    };
-
-    const clearFallbackTimer = () => {
-      if (fallbackTimerId == null) return;
-      window.clearTimeout(fallbackTimerId);
-      fallbackTimerId = null;
-    };
-
-    const measure = (reason: string, canDismiss: boolean) => {
-      if (sessionDismissed) return;
-
-      const resolution = resolveChatKeyboardLift(
-        baseline,
-        readViewportSnapshot(),
-      );
-
-      if (resolution.keyboardVisible) {
-        keyboardObserved = true;
-        applyLift(resolution.lift, resolution.source);
-        return;
-      }
-
-      if ((keyboardObserved || fallbackApplied) && canDismiss) {
-        sessionDismissed = true;
-        clearFallbackTimer();
-        applyLift(0, "reset");
-        log.debug("[chat-keyboard] dismissed", { reason });
-      }
-    };
-
-    const scheduleMeasure = (reason: string, canDismiss: boolean) => {
-      pendingReason = reason;
-      pendingCanDismiss ||= canDismiss;
-      if (frameId != null) return;
-
-      frameId = window.requestAnimationFrame(() => {
-        frameId = null;
-        const nextReason = pendingReason;
-        const nextCanDismiss = pendingCanDismiss;
-        pendingCanDismiss = false;
-        measure(nextReason, nextCanDismiss);
-      });
-    };
-
-    const handleVisualResize = () => scheduleMeasure("visual-resize", true);
-    const handleVisualScroll = () => scheduleMeasure("visual-scroll", false);
-    const handleWindowResize = () => scheduleMeasure("window-resize", true);
-    const handleVirtualKeyboardChange = () =>
-      scheduleMeasure("virtual-keyboard", true);
-    const resetSession = (reason: string) => {
-      sessionDismissed = true;
-      clearFallbackTimer();
-      applyLift(0, "reset");
-      log.debug("[chat-keyboard] reset", { reason });
-    };
-    const handleOrientationChange = () => resetSession("orientationchange");
-    const handleVisibilityChange = () => {
-      if (document.visibilityState === "hidden") {
-        resetSession("visibilitychange");
-      }
-    };
-
-    visualViewport?.addEventListener("resize", handleVisualResize);
-    visualViewport?.addEventListener("scroll", handleVisualScroll);
-    virtualKeyboard?.addEventListener(
-      "geometrychange",
-      handleVirtualKeyboardChange,
-    );
-    window.addEventListener("resize", handleWindowResize);
-    window.addEventListener("orientationchange", handleOrientationChange);
-    document.addEventListener("visibilitychange", handleVisibilityChange);
-
-    scheduleMeasure("focus", false);
-    fallbackTimerId = window.setTimeout(() => {
-      fallbackTimerId = null;
-      if (!activeRef.current || sessionDismissed) return;
-
-      const resolution = resolveChatKeyboardLift(
-        baseline,
-        readViewportSnapshot(),
-      );
-      if (resolution.keyboardVisible) {
-        keyboardObserved = true;
-        applyLift(resolution.lift, resolution.source);
-        return;
-      }
-      if (!fallbackAllowed) return;
-
-      fallbackApplied = true;
-      applyLift(
-        resolveChatKeyboardFallbackLift(baseline.layoutHeight),
-        "fallback",
-      );
-    }, CHAT_KEYBOARD_FALLBACK_DELAY_MS);
-
-    return () => {
-      if (frameId != null) window.cancelAnimationFrame(frameId);
-      clearFallbackTimer();
-      visualViewport?.removeEventListener("resize", handleVisualResize);
-      visualViewport?.removeEventListener("scroll", handleVisualScroll);
-      virtualKeyboard?.removeEventListener(
-        "geometrychange",
-        handleVirtualKeyboardChange,
-      );
-      window.removeEventListener("resize", handleWindowResize);
-      window.removeEventListener("orientationchange", handleOrientationChange);
-      document.removeEventListener("visibilitychange", handleVisibilityChange);
-      clearInputLift(container);
-    };
-  }, [active, containerRef]);
-}
-
-function readViewportBaseline(): ChatKeyboardViewportBaseline {
-  return {
-    layoutHeight: window.innerHeight,
-    visualHeight: window.visualViewport?.height ?? window.innerHeight,
-  };
-}
-
-function readViewportSnapshot(): ChatKeyboardViewportSnapshot {
-  const visualViewport = window.visualViewport;
-  return {
-    layoutHeight: window.innerHeight,
-    visualHeight: visualViewport?.height ?? window.innerHeight,
-    visualScale: visualViewport?.scale ?? 1,
-    virtualKeyboardHeight: getVirtualKeyboard()?.boundingRect?.height ?? 0,
-  };
-}
-
-function getVirtualKeyboard(): VirtualKeyboardLike | null {
-  return (
-    (navigator as NavigatorWithVirtualKeyboard).virtualKeyboard ?? null
-  );
-}
-
-function clearInputLift(container: HTMLElement): void {
-  container.style.removeProperty(CHAT_INPUT_LIFT_VAR);
-}

src/app/chat/hooks/use-chat-keyboard-diagnostics.ts

@@ -6,7 +6,6 @@ import { BrowserDetector } from "@/utils/browser-detect";
 import { PlatformDetector } from "@/utils/platform-detect";
 
 const CHAT_KEYBOARD_DEBUG_PARAM = "keyboard_debug";
-const CHAT_INPUT_LIFT_VAR = "--chat-input-lift";
 
 interface VirtualKeyboardLike extends EventTarget {
   readonly boundingRect?: Pick<
@@ -41,7 +40,11 @@ export interface ChatKeyboardDebugSnapshot {
   activeElement: string | null;
   activeBottom: number | null;
   activeFocused: boolean;
-  inputLift: string | null;
+  inputBarTop: number | null;
+  inputBarBottom: number | null;
+  appViewportHeight: string | null;
+  appVisibleHeight: string | null;
+  appVisibleOffsetTop: string | null;
   viewportMeta: string | null;
   platform: {
     name: string;
@@ -151,6 +154,8 @@ function createChatKeyboardDebugSnapshot(
       : null;
   const platform = PlatformDetector.getPlatformInfo();
   const browser = BrowserDetector.getBrowserInfo();
+  const rootStyle = document.documentElement.style;
+  const inputBarRect = containerRef.current?.getBoundingClientRect() ?? null;
 
   return {
     event,
@@ -176,8 +181,14 @@ function createChatKeyboardDebugSnapshot(
     activeElement: activeElement?.tagName ?? null,
     activeBottom: activeRect?.bottom ?? null,
     activeFocused: activeElement !== document.body,
-    inputLift:
+    inputBarTop: inputBarRect?.top ?? null,
-      containerRef.current?.style.getPropertyValue(CHAT_INPUT_LIFT_VAR) || null,
+    inputBarBottom: inputBarRect?.bottom ?? null,
+    appViewportHeight:
+      rootStyle.getPropertyValue("--app-viewport-height") || null,
+    appVisibleHeight:
+      rootStyle.getPropertyValue("--app-visible-height") || null,
+    appVisibleOffsetTop:
+      rootStyle.getPropertyValue("--app-visible-offset-top") || null,
     viewportMeta:
       document.querySelector<HTMLMetaElement>('meta[name="viewport"]')
         ?.content ?? null,

src/app/chat/layout.tsx

@@ -1,12 +1,7 @@
-import type { Viewport } from "next";
 import type { ReactNode } from "react";
 
 import { ChatRouteProviders } from "@/providers/chat-route-providers";
 
-export const viewport: Viewport = {
-  interactiveWidget: "resizes-content",
-};
-
 export default function ChatLayout({ children }: { children: ReactNode }) {
   return <ChatRouteProviders>{children}</ChatRouteProviders>;
 }