First version

src/app/globals.css

@@ -2,26 +2,75 @@
 @tailwind components;
 @tailwind utilities;
 
-:root {
-  --foreground-rgb: 0, 0, 0;
-  --background-start-rgb: 214, 219, 220;
-  --background-end-rgb: 255, 255, 255;
-}
-
-@media (prefers-color-scheme: dark) {
+@layer base {
   :root {
-    --foreground-rgb: 255, 255, 255;
-    --background-start-rgb: 0, 0, 0;
-    --background-end-rgb: 0, 0, 0;
+    --background: 0 0% 100%;
+    --foreground: 222.2 84% 4.9%;
+
+    --card: 0 0% 100%;
+    --card-foreground: 222.2 84% 4.9%;
+
+    --popover: 0 0% 100%;
+    --popover-foreground: 222.2 84% 4.9%;
+
+    --primary: 222.2 47.4% 11.2%;
+    --primary-foreground: 210 40% 98%;
+
+    --secondary: 210 40% 96.1%;
+    --secondary-foreground: 222.2 47.4% 11.2%;
+
+    --muted: 210 40% 96.1%;
+    --muted-foreground: 215.4 16.3% 46.9%;
+
+    --accent: 210 40% 96.1%;
+    --accent-foreground: 222.2 47.4% 11.2%;
+
+    --destructive: 0 84.2% 60.2%;
+    --destructive-foreground: 210 40% 98%;
+
+    --border: 214.3 31.8% 91.4%;
+    --input: 214.3 31.8% 91.4%;
+    --ring: 222.2 84% 4.9%;
+
+    --radius: 0.5rem;
+  }
+
+  .dark {
+    --background: 222.2 84% 4.9%;
+    --foreground: 210 40% 98%;
+
+    --card: 222.2 84% 4.9%;
+    --card-foreground: 210 40% 98%;
+
+    --popover: 222.2 84% 4.9%;
+    --popover-foreground: 210 40% 98%;
+
+    --primary: 210 40% 98%;
+    --primary-foreground: 222.2 47.4% 11.2%;
+
+    --secondary: 217.2 32.6% 17.5%;
+    --secondary-foreground: 210 40% 98%;
+
+    --muted: 217.2 32.6% 17.5%;
+    --muted-foreground: 215 20.2% 65.1%;
+
+    --accent: 217.2 32.6% 17.5%;
+    --accent-foreground: 210 40% 98%;
+
+    --destructive: 0 62.8% 30.6%;
+    --destructive-foreground: 210 40% 98%;
+
+    --border: 217.2 32.6% 17.5%;
+    --input: 217.2 32.6% 17.5%;
+    --ring: 212.7 26.8% 83.9%;
   }
 }
 
-body {
-  color: rgb(var(--foreground-rgb));
-  background: linear-gradient(
-      to bottom,
-      transparent,
-      rgb(var(--background-end-rgb))
-    )
-    rgb(var(--background-start-rgb));
+@layer base {
+  * {
+    @apply border-border;
+  }
+  body {
+    @apply bg-background text-foreground;
+  }
 }

src/app/groups/[groupId]/edit/page.tsx

@@ -0,0 +1,36 @@
+import { GroupForm } from '@/components/group-form'
+import { Button } from '@/components/ui/button'
+import { getGroup, updateGroup } from '@/lib/api'
+import { groupFormSchema } from '@/lib/schemas'
+import { ChevronLeft } from 'lucide-react'
+import Link from 'next/link'
+import { notFound, redirect } from 'next/navigation'
+
+export default async function EditGroupPage({
+  params: { groupId },
+}: {
+  params: { groupId: string }
+}) {
+  const group = await getGroup(groupId)
+  if (!group) notFound()
+
+  async function updateGroupAction(values: unknown) {
+    'use server'
+    const groupFormValues = groupFormSchema.parse(values)
+    const group = await updateGroup(groupId, groupFormValues)
+    redirect(`/groups/${group.id}`)
+  }
+
+  return (
+    <main>
+      <div className="mb-4">
+        <Button variant="ghost" asChild>
+          <Link href={`/groups/${groupId}`}>
+            <ChevronLeft className="w-4 h-4 mr-2" /> Back to group
+          </Link>
+        </Button>
+      </div>
+      <GroupForm group={group} onSubmit={updateGroupAction} />
+    </main>
+  )
+}

src/app/groups/[groupId]/expenses/[expenseId]/edit/page.tsx

@@ -0,0 +1,42 @@
+import { ExpenseForm } from '@/components/expense-form'
+import { Button } from '@/components/ui/button'
+import { getExpense, getGroup, updateExpense } from '@/lib/api'
+import { expenseFormSchema } from '@/lib/schemas'
+import { ChevronLeft } from 'lucide-react'
+import Link from 'next/link'
+import { notFound, redirect } from 'next/navigation'
+
+export default async function EditExpensePage({
+  params: { groupId, expenseId },
+}: {
+  params: { groupId: string; expenseId: string }
+}) {
+  const group = await getGroup(groupId)
+  if (!group) notFound()
+  const expense = await getExpense(groupId, expenseId)
+  if (!expense) notFound()
+
+  async function updateExpenseAction(values: unknown) {
+    'use server'
+    const expenseFormValues = expenseFormSchema.parse(values)
+    await updateExpense(groupId, expenseId, expenseFormValues)
+    redirect(`/groups/${groupId}`)
+  }
+
+  return (
+    <main>
+      <div className="mb-4">
+        <Button variant="ghost" asChild>
+          <Link href={`/groups/${groupId}`}>
+            <ChevronLeft className="w-4 h-4 mr-2" /> Back to group
+          </Link>
+        </Button>
+      </div>
+      <ExpenseForm
+        group={group}
+        expense={expense}
+        onSubmit={updateExpenseAction}
+      />
+    </main>
+  )
+}

src/app/groups/[groupId]/expenses/create/page.tsx

@@ -0,0 +1,37 @@
+import { ExpenseForm } from '@/components/expense-form'
+import { Button } from '@/components/ui/button'
+import { createExpense, getGroup } from '@/lib/api'
+import { expenseFormSchema } from '@/lib/schemas'
+import { ChevronLeft } from 'lucide-react'
+import Link from 'next/link'
+import { notFound, redirect } from 'next/navigation'
+
+export default async function ExpensePage({
+  params: { groupId },
+}: {
+  params: { groupId: string }
+}) {
+  const group = await getGroup(groupId)
+  if (!group) notFound()
+
+  async function createExpenseAction(values: unknown) {
+    'use server'
+    const expenseFormValues = expenseFormSchema.parse(values)
+    await createExpense(expenseFormValues, groupId)
+    redirect(`/groups/${groupId}`)
+  }
+
+  return (
+    <main>
+      <div className="mb-4">
+        <Button variant="ghost" asChild>
+          <Link href={`/groups/${groupId}`}>
+            <ChevronLeft className="w-4 h-4 mr-2" /> Back to group
+          </Link>
+        </Button>
+      </div>
+
+      <ExpenseForm group={group} onSubmit={createExpenseAction} />
+    </main>
+  )
+}

src/app/groups/[groupId]/page.tsx

@@ -0,0 +1,141 @@
+import { SaveGroupLocally } from '@/app/groups/[groupId]/save-recent-group'
+import { Badge } from '@/components/ui/badge'
+import { Button } from '@/components/ui/button'
+import {
+  Card,
+  CardContent,
+  CardDescription,
+  CardHeader,
+  CardTitle,
+} from '@/components/ui/card'
+import {
+  Table,
+  TableBody,
+  TableCell,
+  TableHead,
+  TableHeader,
+  TableRow,
+} from '@/components/ui/table'
+import { getGroup, getGroupExpenses } from '@/lib/api'
+import { ChevronLeft, ChevronRight, Edit, Plus } from 'lucide-react'
+import Link from 'next/link'
+import { notFound } from 'next/navigation'
+
+export default async function GroupPage({
+  params: { groupId },
+}: {
+  params: { groupId: string }
+}) {
+  const group = await getGroup(groupId)
+  if (!group) notFound()
+
+  const expenses = await getGroupExpenses(groupId)
+
+  return (
+    <main>
+      <div className="mb-4 flex justify-between">
+        <Button variant="ghost" asChild>
+          <Link href="/groups">
+            <ChevronLeft className="w-4 h-4 mr-2" /> Back to recent groups
+          </Link>
+        </Button>
+        <Button variant="secondary" asChild>
+          <Link href={`/groups/${groupId}/edit`}>
+            <Edit className="w-4 h-4 mr-2" /> Edit group settings
+          </Link>
+        </Button>
+      </div>
+
+      <h1 className="font-bold mb-4">{group.name}</h1>
+
+      <Card className="mb-4">
+        <div className="flex flex-1">
+          <CardHeader className="flex-1">
+            <CardTitle>Expenses</CardTitle>
+            <CardDescription>
+              Here are the expenses that you created for your group.
+            </CardDescription>
+          </CardHeader>
+          <CardHeader>
+            <Button asChild size="icon">
+              <Link href={`/groups/${groupId}/expenses/create`}>
+                <Plus />
+              </Link>
+            </Button>
+          </CardHeader>
+        </div>
+        <CardContent className="p-0">
+          <Table className="">
+            <TableHeader>
+              <TableRow>
+                <TableHead>Title</TableHead>
+                <TableHead>Paid by</TableHead>
+                <TableHead>Paid for</TableHead>
+                <TableHead className="text-right">Amount</TableHead>
+                <TableHead className="w-0"></TableHead>
+              </TableRow>
+            </TableHeader>
+            <TableBody>
+              {expenses.map((expense) => (
+                <TableRow key={expense.id}>
+                  <TableCell>{expense.title}</TableCell>
+                  <TableCell>
+                    <Badge variant="secondary">
+                      {
+                        group.participants.find(
+                          (p) => p.id === expense.paidById,
+                        )?.name
+                      }
+                    </Badge>
+                  </TableCell>
+                  <TableCell className="flex flex-wrap gap-1">
+                    {expense.paidFor.map((paidFor, index) => (
+                      <Badge variant="secondary" key={index}>
+                        {
+                          group.participants.find(
+                            (p) => p.id === paidFor.participantId,
+                          )?.name
+                        }
+                      </Badge>
+                    ))}
+                  </TableCell>
+                  <TableCell className="text-right tabular-nums">
+                    $ {expense.amount.toFixed(2)}
+                  </TableCell>
+                  <TableCell>
+                    <Button
+                      size="icon"
+                      variant="link"
+                      className="-my-2"
+                      asChild
+                    >
+                      <Link
+                        href={`/groups/${groupId}/expenses/${expense.id}/edit`}
+                      >
+                        <ChevronRight className="w-4 h-4" />
+                      </Link>
+                    </Button>
+                  </TableCell>
+                </TableRow>
+              ))}
+            </TableBody>
+          </Table>
+        </CardContent>
+      </Card>
+
+      <Card className="mb-4">
+        <CardHeader>
+          <CardTitle>Participants</CardTitle>
+        </CardHeader>
+        <CardContent>
+          <ul>
+            {group.participants.map((participant) => (
+              <li key={participant.id}>{participant.name}</li>
+            ))}
+          </ul>
+        </CardContent>
+      </Card>
+      <SaveGroupLocally group={{ id: group.id, name: group.name }} />
+    </main>
+  )
+}

src/app/groups/[groupId]/save-recent-group.tsx

@@ -0,0 +1,18 @@
+'use client'
+import {
+  RecentGroup,
+  saveRecentGroup,
+} from '@/app/groups/recent-groups-helpers'
+import { useEffect } from 'react'
+
+type Props = {
+  group: RecentGroup
+}
+
+export function SaveGroupLocally({ group }: Props) {
+  useEffect(() => {
+    saveRecentGroup(group)
+  }, [])
+
+  return null
+}

src/app/groups/create/page.tsx

@@ -0,0 +1,29 @@
+import { GroupForm } from '@/components/group-form'
+import { Button } from '@/components/ui/button'
+import { createGroup } from '@/lib/api'
+import { groupFormSchema } from '@/lib/schemas'
+import { ChevronLeft } from 'lucide-react'
+import Link from 'next/link'
+import { redirect } from 'next/navigation'
+
+export default function CreateGroupPage() {
+  async function createGroupAction(values: unknown) {
+    'use server'
+    const groupFormValues = groupFormSchema.parse(values)
+    const group = await createGroup(groupFormValues)
+    redirect(`/groups/${group.id}`)
+  }
+
+  return (
+    <main>
+      <div className="mb-4">
+        <Button variant="ghost" asChild>
+          <Link href="/groups">
+            <ChevronLeft className="w-4 h-4 mr-2" /> Back to recent groups
+          </Link>
+        </Button>
+      </div>
+      <GroupForm onSubmit={createGroupAction} />
+    </main>
+  )
+}

src/app/groups/page.tsx

@@ -0,0 +1,14 @@
+import { RecentGroupList } from '@/app/groups/recent-group-list'
+import { Button } from '@/components/ui/button'
+import Link from 'next/link'
+
+export default async function GroupsPage() {
+  return (
+    <main>
+      <Button asChild>
+        <Link href="/groups/create">New group</Link>
+      </Button>
+      <RecentGroupList />
+    </main>
+  )
+}

src/app/groups/recent-group-list.tsx

@@ -0,0 +1,43 @@
+'use client'
+import { getRecentGroups } from '@/app/groups/recent-groups-helpers'
+import { Button } from '@/components/ui/button'
+import Link from 'next/link'
+import { useEffect, useState } from 'react'
+import { z } from 'zod'
+
+const recentGroupsSchema = z.array(
+  z.object({
+    id: z.string().min(1),
+    name: z.string(),
+  }),
+)
+type RecentGroups = z.infer<typeof recentGroupsSchema>
+
+type State = { status: 'pending' } | { status: 'success'; groups: RecentGroups }
+
+export function RecentGroupList() {
+  const [state, setState] = useState<State>({ status: 'pending' })
+
+  useEffect(() => {
+    const groupsInStorage = getRecentGroups()
+    setState({ status: 'success', groups: groupsInStorage })
+  }, [])
+
+  return (
+    <ul className="flex flex-col gap-2 mt-2">
+      {state.status === 'pending' ? (
+        <li>
+          <em>Loading recent groups…</em>
+        </li>
+      ) : (
+        state.groups.map(({ id, name }) => (
+          <li key={id}>
+            <Button asChild variant="outline">
+              <Link href={`/groups/${id}`}>{name}</Link>
+            </Button>
+          </li>
+        ))
+      )}
+    </ul>
+  )
+}

src/app/groups/recent-groups-helpers.ts

@@ -0,0 +1,30 @@
+import { z } from 'zod'
+
+export const recentGroupsSchema = z.array(
+  z.object({
+    id: z.string().min(1),
+    name: z.string(),
+  }),
+)
+
+export type RecentGroups = z.infer<typeof recentGroupsSchema>
+export type RecentGroup = RecentGroups[number]
+
+const STORAGE_KEY = 'recentGroups'
+
+export function getRecentGroups() {
+  const groupsInStorageJson = localStorage.getItem(STORAGE_KEY)
+  const groupsInStorageRaw = groupsInStorageJson
+    ? JSON.parse(groupsInStorageJson)
+    : []
+  const parseResult = recentGroupsSchema.safeParse(groupsInStorageRaw)
+  return parseResult.success ? parseResult.data : []
+}
+
+export function saveRecentGroup(group: RecentGroup) {
+  const recentGroups = getRecentGroups()
+  localStorage.setItem(
+    STORAGE_KEY,
+    JSON.stringify([group, ...recentGroups.filter((rg) => rg.id !== group.id)]),
+  )
+}

src/app/layout.tsx

@@ -1,9 +1,6 @@
 import type { Metadata } from 'next'
-import { Inter } from 'next/font/google'
 import './globals.css'
 
-const inter = Inter({ subsets: ['latin'] })
-
 export const metadata: Metadata = {
   title: 'Create Next App',
   description: 'Generated by create next app',
@@ -16,7 +13,9 @@ export default function RootLayout({
 }) {
   return (
     <html lang="en">
-      <body className={inter.className}>{children}</body>
+      <body>
+        <div className="max-w-screen-md mx-auto p-4">{children}</div>
+      </body>
     </html>
   )
 }

src/app/page.tsx

@@ -1,113 +1,12 @@
-import Image from 'next/image'
+import { Button } from '@/components/ui/button'
+import Link from 'next/link'
 
-export default function Home() {
+export default function HomePage() {
   return (
-    <main className="flex min-h-screen flex-col items-center justify-between p-24">
-      <div className="z-10 max-w-5xl w-full items-center justify-between font-mono text-sm lg:flex">
-        <p className="fixed left-0 top-0 flex w-full justify-center border-b border-gray-300 bg-gradient-to-b from-zinc-200 pb-6 pt-8 backdrop-blur-2xl dark:border-neutral-800 dark:bg-zinc-800/30 dark:from-inherit lg:static lg:w-auto  lg:rounded-xl lg:border lg:bg-gray-200 lg:p-4 lg:dark:bg-zinc-800/30">
-          Get started by editing&nbsp;
-          <code className="font-mono font-bold">src/app/page.tsx</code>
-        </p>
-        <div className="fixed bottom-0 left-0 flex h-48 w-full items-end justify-center bg-gradient-to-t from-white via-white dark:from-black dark:via-black lg:static lg:h-auto lg:w-auto lg:bg-none">
-          <a
-            className="pointer-events-none flex place-items-center gap-2 p-8 lg:pointer-events-auto lg:p-0"
-            href="https://vercel.com?utm_source=create-next-app&utm_medium=appdir-template&utm_campaign=create-next-app"
-            target="_blank"
-            rel="noopener noreferrer"
-          >
-            By{' '}
-            <Image
-              src="/vercel.svg"
-              alt="Vercel Logo"
-              className="dark:invert"
-              width={100}
-              height={24}
-              priority
-            />
-          </a>
-        </div>
-      </div>
-
-      <div className="relative flex place-items-center before:absolute before:h-[300px] before:w-[480px] before:-translate-x-1/2 before:rounded-full before:bg-gradient-radial before:from-white before:to-transparent before:blur-2xl before:content-[''] after:absolute after:-z-20 after:h-[180px] after:w-[240px] after:translate-x-1/3 after:bg-gradient-conic after:from-sky-200 after:via-blue-200 after:blur-2xl after:content-[''] before:dark:bg-gradient-to-br before:dark:from-transparent before:dark:to-blue-700 before:dark:opacity-10 after:dark:from-sky-900 after:dark:via-[#0141ff] after:dark:opacity-40 before:lg:h-[360px] z-[-1]">
-        <Image
-          className="relative dark:drop-shadow-[0_0_0.3rem_#ffffff70] dark:invert"
-          src="/next.svg"
-          alt="Next.js Logo"
-          width={180}
-          height={37}
-          priority
-        />
-      </div>
-
-      <div className="mb-32 grid text-center lg:max-w-5xl lg:w-full lg:mb-0 lg:grid-cols-4 lg:text-left">
-        <a
-          href="https://nextjs.org/docs?utm_source=create-next-app&utm_medium=appdir-template&utm_campaign=create-next-app"
-          className="group rounded-lg border border-transparent px-5 py-4 transition-colors hover:border-gray-300 hover:bg-gray-100 hover:dark:border-neutral-700 hover:dark:bg-neutral-800/30"
-          target="_blank"
-          rel="noopener noreferrer"
-        >
-          <h2 className={`mb-3 text-2xl font-semibold`}>
-            Docs{' '}
-            <span className="inline-block transition-transform group-hover:translate-x-1 motion-reduce:transform-none">
-              -&gt;
-            </span>
-          </h2>
-          <p className={`m-0 max-w-[30ch] text-sm opacity-50`}>
-            Find in-depth information about Next.js features and API.
-          </p>
-        </a>
-
-        <a
-          href="https://nextjs.org/learn?utm_source=create-next-app&utm_medium=appdir-template-tw&utm_campaign=create-next-app"
-          className="group rounded-lg border border-transparent px-5 py-4 transition-colors hover:border-gray-300 hover:bg-gray-100 hover:dark:border-neutral-700 hover:dark:bg-neutral-800/30"
-          target="_blank"
-          rel="noopener noreferrer"
-        >
-          <h2 className={`mb-3 text-2xl font-semibold`}>
-            Learn{' '}
-            <span className="inline-block transition-transform group-hover:translate-x-1 motion-reduce:transform-none">
-              -&gt;
-            </span>
-          </h2>
-          <p className={`m-0 max-w-[30ch] text-sm opacity-50`}>
-            Learn about Next.js in an interactive course with&nbsp;quizzes!
-          </p>
-        </a>
-
-        <a
-          href="https://vercel.com/templates?framework=next.js&utm_source=create-next-app&utm_medium=appdir-template&utm_campaign=create-next-app"
-          className="group rounded-lg border border-transparent px-5 py-4 transition-colors hover:border-gray-300 hover:bg-gray-100 hover:dark:border-neutral-700 hover:dark:bg-neutral-800/30"
-          target="_blank"
-          rel="noopener noreferrer"
-        >
-          <h2 className={`mb-3 text-2xl font-semibold`}>
-            Templates{' '}
-            <span className="inline-block transition-transform group-hover:translate-x-1 motion-reduce:transform-none">
-              -&gt;
-            </span>
-          </h2>
-          <p className={`m-0 max-w-[30ch] text-sm opacity-50`}>
-            Explore the Next.js 13 playground.
-          </p>
-        </a>
-
-        <a
-          href="https://vercel.com/new?utm_source=create-next-app&utm_medium=appdir-template&utm_campaign=create-next-app"
-          className="group rounded-lg border border-transparent px-5 py-4 transition-colors hover:border-gray-300 hover:bg-gray-100 hover:dark:border-neutral-700 hover:dark:bg-neutral-800/30"
-          target="_blank"
-          rel="noopener noreferrer"
-        >
-          <h2 className={`mb-3 text-2xl font-semibold`}>
-            Deploy{' '}
-            <span className="inline-block transition-transform group-hover:translate-x-1 motion-reduce:transform-none">
-              -&gt;
-            </span>
-          </h2>
-          <p className={`m-0 max-w-[30ch] text-sm opacity-50`}>
-            Instantly deploy your Next.js site to a shareable URL with Vercel.
-          </p>
-        </a>
-      </div>
+    <main>
+      <Button asChild variant="link">
+        <Link href="/groups">My groups</Link>
+      </Button>
     </main>
   )
 }