refactor(ui): one cardEdges helper for the three list card stacks

app/src/app/project/[id].tsx

@@ -2,10 +2,10 @@ import { Stack, useLocalSearchParams, useRouter } from "expo-router";
 import { useState } from "react";
 import { FlatList, Pressable, StyleSheet, Text, TextInput, View } from "react-native";
 import Icon from "../../components/Icon";
-import { Button, Chips, Empty, Separator } from "../../components/ui";
+import { Button, cardEdges, Chips, Empty, Separator } from "../../components/ui";
 import { haptic } from "../../lib/haptics";
 import { createTask, dropProject, updateProject, updateTask } from "../../lib/store";
-import { C, radius, shadow, space, type } from "../../lib/theme";
+import { C, radius, space, type } from "../../lib/theme";
 import { useStore } from "../../lib/useStore";
 import type { ProjectStatus } from "../../lib/types";
 
@@ -60,8 +60,7 @@ export default function ProjectDetail() {
           <Pressable
             style={({ pressed }) => [
               s.row,
-              index === 0 && s.first,
-              index === tasks.length - 1 && s.last,
+              ...cardEdges(index, tasks.length),
               pressed && { backgroundColor: C.surface2 },
             ]}
             onPress={() => router.push(`/task/${item.id}`)}
@@ -122,13 +121,6 @@ const s = StyleSheet.create({
     gap: space.md,
     paddingVertical: space.md + 2,
     paddingHorizontal: space.lg,
-    backgroundColor: C.surface,
-  },
-  first: { borderTopLeftRadius: radius.lg, borderTopRightRadius: radius.lg },
-  last: {
-    borderBottomLeftRadius: radius.lg,
-    borderBottomRightRadius: radius.lg,
-    ...shadow.card,
   },
   checkbox: { width: 21, height: 21, borderRadius: 7, borderWidth: 1.5, borderColor: C.muted },
   title: { ...type.row, color: C.text },

app/src/app/today.tsx

@@ -1,8 +1,8 @@
 import { SectionList, StyleSheet, View } from "react-native";
 import TaskRow, { TaskSeparator } from "../components/TaskRow";
-import { Empty, SectionHeader } from "../components/ui";
+import { cardEdges, Empty, SectionHeader } from "../components/ui";
 import { todayTasks } from "../lib/store";
-import { C, radius, shadow, space } from "../lib/theme";
+import { C, space } from "../lib/theme";
 import { useStore } from "../lib/useStore";
 
 export default function Today() {
@@ -22,13 +22,7 @@ export default function Today() {
       // Each section is its own rounded card, so the first and last rows in a
       // section round their outer corners.
       renderItem={({ item, index, section }) => (
-        <View
-          style={[
-            s.row,
-            index === 0 && s.first,
-            index === section.data.length - 1 && s.last,
-          ]}
-        >
+        <View style={cardEdges(index, section.data.length)}>
           <TaskRow task={item} showStatus />
         </View>
       )}
@@ -47,11 +41,4 @@ export default function Today() {
 const s = StyleSheet.create({
   screen: { flex: 1, backgroundColor: C.bg },
   content: { paddingHorizontal: space.lg, paddingBottom: 40 },
-  row: { backgroundColor: C.surface },
-  first: { borderTopLeftRadius: radius.lg, borderTopRightRadius: radius.lg },
-  last: {
-    borderBottomLeftRadius: radius.lg,
-    borderBottomRightRadius: radius.lg,
-    ...shadow.card,
-  },
 });

app/src/components/TaskListScreen.tsx

@@ -7,6 +7,7 @@ import { C, radius, shadow, space, type } from "../lib/theme";
 import { useStore } from "../lib/useStore";
 import type { TaskStatus } from "../lib/types";
 import TaskRow, { TaskSeparator } from "./TaskRow";
+import { cardEdges } from "./ui";
 
 // Deferred tasks are hidden from these lists until their date — you can't act
 // on them yet, so they shouldn't cost attention. A one-line footer keeps them
@@ -57,14 +58,7 @@ export default function TaskListScreen({
           const i = getIndex() ?? 0;
           return (
             <ScaleDecorator activeScale={1.02}>
-              <View
-                style={[
-                  s.row,
-                  i === 0 && s.first,
-                  i === tasks.length - 1 && s.last,
-                  isActive && s.lifted,
-                ]}
-              >
+              <View style={[...cardEdges(i, tasks.length), isActive && s.lifted]}>
                 <TaskRow
                   task={item}
                   uncheckTo={status === "done" ? "next" : status}
@@ -108,13 +102,6 @@ export default function TaskListScreen({
 const s = StyleSheet.create({
   screen: { flex: 1, backgroundColor: C.bg },
   content: { paddingHorizontal: space.lg, paddingTop: space.md, paddingBottom: 96 },
-  row: { backgroundColor: C.surface },
-  first: { borderTopLeftRadius: radius.lg, borderTopRightRadius: radius.lg },
-  last: {
-    borderBottomLeftRadius: radius.lg,
-    borderBottomRightRadius: radius.lg,
-    ...shadow.card,
-  },
   lifted: { borderRadius: radius.lg, ...shadow.fab },
   empty: {
     ...type.body,

app/src/components/ui.tsx

@@ -36,6 +36,15 @@ export function Card({ children, style }: { children: React.ReactNode; style?: V
   return <View style={[u.card, style]}>{children}</View>;
 }
 
+/**
+ * Row background plus rounded outer corners for the first and last row of a
+ * list, so a plain FlatList reads as one card without wrapping it in a `Card`
+ * (which would break drag-and-drop and section headers).
+ */
+export function cardEdges(index: number, count: number) {
+  return [u.cardRow, index === 0 && u.cardTop, index === count - 1 && u.cardBottom];
+}
+
 /** Inset hairline for use between rows inside a `Card`. */
 export function Separator({ inset = 0 }: { inset?: number }) {
   return <View style={[u.separator, { marginLeft: inset }]} />;
@@ -165,6 +174,14 @@ export function Button({
 const u = StyleSheet.create({
   screen: { flex: 1, backgroundColor: C.bg },
 
+  cardRow: { backgroundColor: C.surface },
+  cardTop: { borderTopLeftRadius: radius.lg, borderTopRightRadius: radius.lg },
+  cardBottom: {
+    borderBottomLeftRadius: radius.lg,
+    borderBottomRightRadius: radius.lg,
+    ...shadow.card,
+  },
+
   titleRow: {
     flexDirection: "row",
     alignItems: "center",