Add 'apps/mobile/' from commit '5fa30f365f21531094cd4d2045042bb4f1370ac3'

git-subtree-dir: apps/mobile
git-subtree-mainline: 86f8987dff
git-subtree-split: 5fa30f365f

apps/mobile/lib/tab-bar-insets.ts

@@ -0,0 +1,67 @@
+import { Platform, useWindowDimensions } from "react-native";
+import { useSafeAreaFrame, useSafeAreaInsets } from "react-native-safe-area-context";
+
+import { spacing } from "@/constants/theme";
+
+/** Standard UITabBar content height (home indicator is separate). */
+const IOS_TAB_BAR_HEIGHT = 49;
+
+/** Trim extra inset so scroll content sits closer to the tab bar. */
+const TAB_BAR_PADDING_TRIM = spacing.lg;
+
+/**
+ * Pixels between the bottom of the safe-area layout frame and the window bottom.
+ */
+function useBelowLayoutFrame(): number {
+  const { height: windowHeight } = useWindowDimensions();
+  const frame = useSafeAreaFrame();
+
+  return Math.max(0, windowHeight - frame.y - frame.height);
+}
+
+/** Native tab bar height excluding the home-indicator inset. */
+export function useNativeTabBarHeight(): number {
+  const belowLayoutFrame = useBelowLayoutFrame();
+  const { bottom: homeIndicator } = useSafeAreaInsets();
+  const measured = Math.max(0, belowLayoutFrame - homeIndicator);
+
+  if (measured > 0) return measured;
+  return Platform.OS === "ios" ? IOS_TAB_BAR_HEIGHT : 0;
+}
+
+/**
+ * Bottom padding so scroll content can clear the floating native tab bar.
+ * Uses tab bar + home indicator as the target — layout-frame measurement can
+ * over-report and leave a large empty scroll gap above the tab bar.
+ */
+export function useTabBarScrollPadding(): number {
+  const { bottom: homeIndicator } = useSafeAreaInsets();
+  const tabBar = useNativeTabBarHeight();
+  const clearance = tabBar + homeIndicator;
+
+  return Math.max(spacing.xs, clearance - TAB_BAR_PADDING_TRIM);
+}
+
+/** Bottom offset for floating action buttons above the tab bar. */
+export function useFloatingActionBottom(): number {
+  const { bottom: homeIndicator } = useSafeAreaInsets();
+  const tabBar = useNativeTabBarHeight();
+
+  return tabBar + homeIndicator + spacing.xs;
+}
+
+/**
+ * Bottom padding for tab-root ScrollViews (Dashboard, Invoices, etc.).
+ * Uses full tab-bar clearance — do not trim; undershooting hides content under the bar.
+ */
+export function useTabScreenScrollPadding(): number {
+  const { bottom: homeIndicator } = useSafeAreaInsets();
+  const tabBar = useNativeTabBarHeight();
+
+  return tabBar + homeIndicator + spacing.sm;
+}
+
+/** @deprecated Use useTabBarScrollPadding */
+export function useTabBarInset() {
+  return useTabBarScrollPadding();
+}