Enhance Cospend with debt breakdown and predefined users

- Add EnhancedBalance component with integrated single-user debt display
- Create DebtBreakdown component for multi-user debt overview
- Add predefined users configuration (alexander, anna)
- Implement personal + equal split payment method
- Add profile pictures throughout payment interfaces
- Integrate debt information with profile pictures in balance view
- Auto-hide debt breakdown when single user (shows in balance instead)
- Support both manual and predefined user management modes

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

src/lib/components/DebtBreakdown.svelte

@@ -0,0 +1,246 @@
+<script>
+  import { onMount } from 'svelte';
+  import ProfilePicture from './ProfilePicture.svelte';
+
+  let debtData = {
+    whoOwesMe: [],
+    whoIOwe: [],
+    totalOwedToMe: 0,
+    totalIOwe: 0
+  };
+  let loading = true;
+  let error = null;
+  
+  $: shouldHide = getShouldHide();
+  
+  function getShouldHide() {
+    const totalUsers = debtData.whoOwesMe.length + debtData.whoIOwe.length;
+    return totalUsers <= 1; // Hide if 0 or 1 user (1 user is handled by enhanced balance)
+  }
+
+  onMount(async () => {
+    await fetchDebtBreakdown();
+  });
+
+  async function fetchDebtBreakdown() {
+    try {
+      loading = true;
+      const response = await fetch('/api/cospend/debts');
+      if (!response.ok) {
+        throw new Error('Failed to fetch debt breakdown');
+      }
+      debtData = await response.json();
+    } catch (err) {
+      error = err.message;
+    } finally {
+      loading = false;
+    }
+  }
+
+  function formatCurrency(amount) {
+    return new Intl.NumberFormat('de-CH', {
+      style: 'currency',
+      currency: 'CHF'
+    }).format(amount);
+  }
+</script>
+
+{#if !shouldHide}
+<div class="debt-breakdown">
+  <h2>Debt Overview</h2>
+  
+  {#if loading}
+    <div class="loading">Loading debt breakdown...</div>
+  {:else if error}
+    <div class="error">Error: {error}</div>
+  {:else}
+    <div class="debt-sections">
+      {#if debtData.whoOwesMe.length > 0}
+        <div class="debt-section owed-to-me">
+          <h3>Who owes you</h3>
+          <div class="total-amount positive">
+            Total: {formatCurrency(debtData.totalOwedToMe)}
+          </div>
+          
+          <div class="debt-list">
+            {#each debtData.whoOwesMe as debt}
+              <div class="debt-item">
+                <div class="debt-user">
+                  <ProfilePicture username={debt.username} size={40} />
+                  <div class="user-details">
+                    <span class="username">{debt.username}</span>
+                    <span class="amount positive">{formatCurrency(debt.netAmount)}</span>
+                  </div>
+                </div>
+                <div class="transaction-count">
+                  {debt.transactions.length} transaction{debt.transactions.length !== 1 ? 's' : ''}
+                </div>
+              </div>
+            {/each}
+          </div>
+        </div>
+      {/if}
+
+      {#if debtData.whoIOwe.length > 0}
+        <div class="debt-section owe-to-others">
+          <h3>You owe</h3>
+          <div class="total-amount negative">
+            Total: {formatCurrency(debtData.totalIOwe)}
+          </div>
+          
+          <div class="debt-list">
+            {#each debtData.whoIOwe as debt}
+              <div class="debt-item">
+                <div class="debt-user">
+                  <ProfilePicture username={debt.username} size={40} />
+                  <div class="user-details">
+                    <span class="username">{debt.username}</span>
+                    <span class="amount negative">{formatCurrency(debt.netAmount)}</span>
+                  </div>
+                </div>
+                <div class="transaction-count">
+                  {debt.transactions.length} transaction{debt.transactions.length !== 1 ? 's' : ''}
+                </div>
+              </div>
+            {/each}
+          </div>
+        </div>
+      {/if}
+    </div>
+  {/if}
+</div>
+{/if}
+
+<style>
+  .debt-breakdown {
+    background: white;
+    padding: 1.5rem;
+    border-radius: 0.75rem;
+    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
+    margin-bottom: 2rem;
+  }
+
+  .debt-breakdown h2 {
+    margin-bottom: 1.5rem;
+    color: #333;
+    font-size: 1.4rem;
+  }
+
+  .loading, .error {
+    text-align: center;
+    padding: 2rem;
+    color: #666;
+  }
+
+  .error {
+    color: #d32f2f;
+    background-color: #ffebee;
+    border-radius: 0.5rem;
+  }
+
+  .no-debts {
+    text-align: center;
+    padding: 2rem;
+    color: #666;
+    font-size: 1.1rem;
+  }
+
+  .debt-sections {
+    display: grid;
+    gap: 1.5rem;
+  }
+
+  @media (min-width: 768px) {
+    .debt-sections {
+      grid-template-columns: 1fr 1fr;
+    }
+  }
+
+  .debt-section {
+    border-radius: 0.5rem;
+    padding: 1rem;
+  }
+
+  .debt-section.owed-to-me {
+    background: linear-gradient(135deg, #e8f5e8, #f0f8f0);
+    border: 1px solid #c8e6c9;
+  }
+
+  .debt-section.owe-to-others {
+    background: linear-gradient(135deg, #ffeaea, #fff5f5);
+    border: 1px solid #ffcdd2;
+  }
+
+  .debt-section h3 {
+    margin-bottom: 0.5rem;
+    font-size: 1.1rem;
+    color: #333;
+  }
+
+  .total-amount {
+    font-weight: bold;
+    font-size: 1.2rem;
+    margin-bottom: 1rem;
+  }
+
+  .total-amount.positive {
+    color: #2e7d32;
+  }
+
+  .total-amount.negative {
+    color: #d32f2f;
+  }
+
+  .debt-list {
+    display: flex;
+    flex-direction: column;
+    gap: 0.75rem;
+  }
+
+  .debt-item {
+    display: flex;
+    justify-content: space-between;
+    align-items: center;
+    padding: 0.75rem;
+    background: white;
+    border-radius: 0.5rem;
+    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
+  }
+
+  .debt-user {
+    display: flex;
+    align-items: center;
+    gap: 0.75rem;
+    flex: 1;
+  }
+
+  .user-details {
+    display: flex;
+    flex-direction: column;
+    gap: 0.25rem;
+  }
+
+  .username {
+    font-weight: 500;
+    color: #333;
+  }
+
+  .amount {
+    font-weight: bold;
+    font-size: 1rem;
+  }
+
+  .amount.positive {
+    color: #2e7d32;
+  }
+
+  .amount.negative {
+    color: #d32f2f;
+  }
+
+  .transaction-count {
+    color: #666;
+    font-size: 0.85rem;
+    text-align: right;
+  }
+</style>

src/lib/components/EnhancedBalance.svelte

@@ -0,0 +1,334 @@
+<script>
+  import { onMount } from 'svelte';
+  import ProfilePicture from './ProfilePicture.svelte';
+
+  let balance = {
+    netBalance: 0,
+    recentSplits: []
+  };
+  let debtData = {
+    whoOwesMe: [],
+    whoIOwe: [],
+    totalOwedToMe: 0,
+    totalIOwe: 0
+  };
+  let loading = true;
+  let error = null;
+  let singleDebtUser = null;
+  let shouldShowIntegratedView = false;
+
+  function getSingleDebtUser() {
+    const totalUsers = debtData.whoOwesMe.length + debtData.whoIOwe.length;
+    
+    if (totalUsers === 1) {
+      if (debtData.whoOwesMe.length === 1) {
+        return {
+          type: 'owesMe',
+          user: debtData.whoOwesMe[0],
+          amount: debtData.whoOwesMe[0].netAmount
+        };
+      } else if (debtData.whoIOwe.length === 1) {
+        return {
+          type: 'iOwe', 
+          user: debtData.whoIOwe[0],
+          amount: debtData.whoIOwe[0].netAmount
+        };
+      }
+    }
+    
+    return null;
+  }
+
+  $: {
+    // Recalculate when debtData changes
+    singleDebtUser = getSingleDebtUser();
+    shouldShowIntegratedView = singleDebtUser !== null;
+    
+    // Temporary debug logging
+    if (!loading) {
+      console.log('🔍 Debug Info:');
+      console.log('- debtData:', debtData);
+      console.log('- whoOwesMe length:', debtData.whoOwesMe.length);
+      console.log('- whoIOwe length:', debtData.whoIOwe.length);
+      console.log('- singleDebtUser:', singleDebtUser);
+      console.log('- shouldShowIntegratedView:', shouldShowIntegratedView);
+    }
+  }
+  
+
+  onMount(async () => {
+    await Promise.all([fetchBalance(), fetchDebtBreakdown()]);
+  });
+
+  async function fetchBalance() {
+    try {
+      const response = await fetch('/api/cospend/balance');
+      if (!response.ok) {
+        throw new Error('Failed to fetch balance');
+      }
+      balance = await response.json();
+    } catch (err) {
+      error = err.message;
+    }
+  }
+
+  async function fetchDebtBreakdown() {
+    try {
+      const response = await fetch('/api/cospend/debts');
+      if (!response.ok) {
+        throw new Error('Failed to fetch debt breakdown');
+      }
+      debtData = await response.json();
+    } catch (err) {
+      error = err.message;
+    } finally {
+      loading = false;
+    }
+  }
+
+  function formatCurrency(amount) {
+    return new Intl.NumberFormat('de-CH', {
+      style: 'currency',
+      currency: 'CHF'
+    }).format(Math.abs(amount));
+  }
+
+</script>
+
+<div class="balance-cards">
+  <div class="balance-card net-balance" 
+       class:positive={balance.netBalance <= 0} 
+       class:negative={balance.netBalance > 0}
+       class:enhanced={shouldShowIntegratedView}>
+    
+    {#if loading}
+      <div class="loading-content">
+        <h3>Your Balance</h3>
+        <div class="loading">Loading...</div>
+      </div>
+    {:else if error}
+      <h3>Your Balance</h3>
+      <div class="error">Error: {error}</div>
+    {:else if shouldShowIntegratedView}
+      <!-- Enhanced view with single user debt -->
+      <h3>Your Balance</h3>
+      <div class="enhanced-balance">
+        <div class="main-amount">
+          {#if balance.netBalance < 0}
+            <span class="positive">+{formatCurrency(balance.netBalance)}</span>
+            <small>You are owed</small>
+          {:else if balance.netBalance > 0}
+            <span class="negative">-{formatCurrency(balance.netBalance)}</span>
+            <small>You owe</small>
+          {:else}
+            <span class="even">CHF 0.00</span>
+            <small>You're all even</small>
+          {/if}
+        </div>
+        
+        <div class="debt-details">
+          <div class="debt-user">
+            {#if singleDebtUser && singleDebtUser.user}
+              <!-- Debug: ProfilePicture with username: {singleDebtUser.user.username} -->
+              <ProfilePicture username={singleDebtUser.user.username} size={40} />
+              <div class="user-info">
+                <span class="username">{singleDebtUser.user.username}</span>
+                <span class="debt-description">
+                  {#if singleDebtUser.type === 'owesMe'}
+                    owes you {formatCurrency(singleDebtUser.amount)}
+                  {:else}
+                    you owe {formatCurrency(singleDebtUser.amount)}
+                  {/if}
+                </span>
+              </div>
+            {:else}
+              <div>Debug: No singleDebtUser data</div>
+            {/if}
+          </div>
+          <div class="transaction-count">
+            {#if singleDebtUser && singleDebtUser.user && singleDebtUser.user.transactions}
+              {singleDebtUser.user.transactions.length} transaction{singleDebtUser.user.transactions.length !== 1 ? 's' : ''}
+            {/if}
+          </div>
+        </div>
+      </div>
+    {:else}
+      <!-- Standard balance view -->
+      <h3>Your Balance</h3>
+      <div class="amount">
+        {#if balance.netBalance < 0}
+          <span class="positive">+{formatCurrency(balance.netBalance)}</span>
+          <small>You are owed</small>
+        {:else if balance.netBalance > 0}
+          <span class="negative">-{formatCurrency(balance.netBalance)}</span>
+          <small>You owe</small>
+        {:else}
+          <span class="even">CHF 0.00</span>
+          <small>You're all even</small>
+        {/if}
+      </div>
+    {/if}
+  </div>
+</div>
+
+<style>
+  .balance-cards {
+    display: flex;
+    justify-content: center;
+    margin-bottom: 2rem;
+  }
+
+  .balance-card {
+    background: white;
+    padding: 2rem;
+    border-radius: 0.75rem;
+    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
+    text-align: center;
+    min-width: 300px;
+  }
+
+  .balance-card.enhanced {
+    min-width: 400px;
+    text-align: left;
+  }
+
+  .balance-card.net-balance {
+    background: linear-gradient(135deg, #f5f5f5, #e8e8e8);
+  }
+
+  .balance-card.net-balance.positive {
+    background: linear-gradient(135deg, #e8f5e8, #d4edda);
+  }
+
+  .balance-card.net-balance.negative {
+    background: linear-gradient(135deg, #ffeaea, #f8d7da);
+  }
+
+  .balance-card h3 {
+    margin-bottom: 1rem;
+    color: #555;
+    font-size: 1.1rem;
+    text-align: center;
+  }
+
+  .loading-content {
+    text-align: center;
+  }
+
+  .loading {
+    color: #666;
+  }
+
+  .error {
+    color: #d32f2f;
+    background-color: #ffebee;
+    border-radius: 0.5rem;
+    padding: 1rem;
+  }
+
+  .amount {
+    font-size: 2rem;
+    font-weight: bold;
+    margin-bottom: 0.5rem;
+  }
+
+  .amount small {
+    display: block;
+    font-size: 0.9rem;
+    font-weight: normal;
+    color: #666;
+    margin-top: 0.5rem;
+  }
+
+  .enhanced-balance {
+    display: flex;
+    flex-direction: column;
+    gap: 1.5rem;
+  }
+
+  .main-amount {
+    text-align: center;
+    font-size: 1.8rem;
+    font-weight: bold;
+  }
+
+  .main-amount small {
+    display: block;
+    font-size: 0.9rem;
+    font-weight: normal;
+    color: #666;
+    margin-top: 0.5rem;
+  }
+
+  .debt-details {
+    background: rgba(255, 255, 255, 0.5);
+    padding: 1rem;
+    border-radius: 0.5rem;
+    display: flex;
+    justify-content: space-between;
+    align-items: center;
+  }
+
+  .debt-user {
+    display: flex;
+    align-items: center;
+    gap: 0.75rem;
+    flex: 1;
+  }
+
+  .user-info {
+    display: flex;
+    flex-direction: column;
+    gap: 0.25rem;
+  }
+
+  .username {
+    font-weight: 600;
+    color: #333;
+    font-size: 1rem;
+  }
+
+  .debt-description {
+    color: #666;
+    font-size: 0.9rem;
+  }
+
+  .transaction-count {
+    color: #666;
+    font-size: 0.85rem;
+    text-align: right;
+  }
+
+  .positive {
+    color: #2e7d32;
+  }
+
+  .negative {
+    color: #d32f2f;
+  }
+
+  .even {
+    color: #666;
+  }
+
+  @media (max-width: 600px) {
+    .balance-card {
+      min-width: unset;
+      width: 100%;
+    }
+    
+    .balance-card.enhanced {
+      min-width: unset;
+    }
+
+    .debt-details {
+      flex-direction: column;
+      gap: 0.75rem;
+      align-items: flex-start;
+    }
+
+    .transaction-count {
+      text-align: left;
+    }
+  }
+</style>

src/lib/components/PaymentModal.svelte

@@ -79,6 +79,8 @@
       return `Split equally among ${payment.splits.length} people`;
     } else if (payment.splitMethod === 'full') {
       return `Paid in full by ${payment.paidBy}`;
+    } else if (payment.splitMethod === 'personal_equal') {
+      return `Personal amounts + equal split among ${payment.splits.length} people`;
     } else {
       return `Custom split among ${payment.splits.length} people`;
     }

src/lib/config/users.ts

@@ -0,0 +1,16 @@
+// Predefined users configuration for Cospend
+// When this array has exactly 2 users, the system will always split between them
+// For more users, manual selection is allowed
+
+export const PREDEFINED_USERS = [
+  'alexander',
+  'anna'
+];
+
+export function isPredefinedUsersMode(): boolean {
+  return PREDEFINED_USERS.length === 2;
+}
+
+export function getAvailableUsers(): string[] {
+  return [...PREDEFINED_USERS];
+}

src/models/Payment.ts

@@ -10,7 +10,7 @@ export interface IPayment {
   date: Date;
   image?: string; // path to uploaded image
   category: 'groceries' | 'shopping' | 'travel' | 'restaurant' | 'utilities' | 'fun';
-  splitMethod: 'equal' | 'full' | 'proportional';
+  splitMethod: 'equal' | 'full' | 'proportional' | 'personal_equal';
   createdBy: string; // username/nickname of the person who created the payment
   createdAt?: Date;
   updatedAt?: Date;
@@ -61,7 +61,7 @@ const PaymentSchema = new mongoose.Schema(
     splitMethod: {
       type: String,
       required: true,
-      enum: ['equal', 'full', 'proportional'],
+      enum: ['equal', 'full', 'proportional', 'personal_equal'],
       default: 'equal'
     },
     createdBy: { 

src/models/PaymentSplit.ts

@@ -6,6 +6,7 @@ export interface IPaymentSplit {
   username: string; // username/nickname of the person who owes/is owed
   amount: number; // amount this person owes (positive) or is owed (negative)
   proportion?: number; // for proportional splits, the proportion (e.g., 0.5 for 50%)
+  personalAmount?: number; // for personal_equal splits, the personal portion for this user
   settled: boolean; // whether this split has been settled
   settledAt?: Date;
   createdAt?: Date;
@@ -33,6 +34,10 @@ const PaymentSplitSchema = new mongoose.Schema(
       min: 0,
       max: 1 
     },
+    personalAmount: {
+      type: Number,
+      min: 0
+    },
     settled: { 
       type: Boolean, 
       default: false 

src/routes/api/cospend/debts/+server.ts

@@ -0,0 +1,110 @@
+import type { RequestHandler } from '@sveltejs/kit';
+import { PaymentSplit } from '../../../../models/PaymentSplit';
+import { Payment } from '../../../../models/Payment';
+import { dbConnect, dbDisconnect } from '../../../../utils/db';
+import { error, json } from '@sveltejs/kit';
+
+interface DebtSummary {
+  username: string;
+  netAmount: number; // positive = you owe them, negative = they owe you
+  transactions: {
+    paymentId: string;
+    title: string;
+    amount: number;
+    date: Date;
+    category: string;
+  }[];
+}
+
+export const GET: RequestHandler = async ({ locals }) => {
+  const auth = await locals.auth();
+  if (!auth || !auth.user?.nickname) {
+    throw error(401, 'Not logged in');
+  }
+
+  const currentUser = auth.user.nickname;
+
+  await dbConnect();
+  
+  try {
+    // Get all splits for the current user
+    const userSplits = await PaymentSplit.find({ username: currentUser })
+      .populate('paymentId')
+      .lean();
+
+    // Get all other users who have splits with payments involving the current user
+    const paymentIds = userSplits.map(split => split.paymentId._id);
+    const allRelatedSplits = await PaymentSplit.find({
+      paymentId: { $in: paymentIds },
+      username: { $ne: currentUser }
+    })
+      .populate('paymentId')
+      .lean();
+
+    // Group debts by user
+    const debtsByUser = new Map<string, DebtSummary>();
+
+    // Process current user's splits to understand what they owe/are owed
+    for (const split of userSplits) {
+      const payment = split.paymentId as any;
+      if (!payment) continue;
+
+      // Find other participants in this payment
+      const otherSplits = allRelatedSplits.filter(s => 
+        s.paymentId._id.toString() === split.paymentId._id.toString()
+      );
+
+      for (const otherSplit of otherSplits) {
+        const otherUser = otherSplit.username;
+        
+        if (!debtsByUser.has(otherUser)) {
+          debtsByUser.set(otherUser, {
+            username: otherUser,
+            netAmount: 0,
+            transactions: []
+          });
+        }
+
+        const debt = debtsByUser.get(otherUser)!;
+        
+        // Current user's amount: positive = they owe, negative = they are owed
+        // We want to show net between the two users
+        debt.netAmount += split.amount;
+        
+        debt.transactions.push({
+          paymentId: payment._id.toString(),
+          title: payment.title,
+          amount: split.amount,
+          date: payment.date,
+          category: payment.category
+        });
+      }
+    }
+
+    // Convert map to array and sort by absolute amount (largest debts first)
+    const debtSummaries = Array.from(debtsByUser.values())
+      .filter(debt => Math.abs(debt.netAmount) > 0.01) // Filter out tiny amounts
+      .sort((a, b) => Math.abs(b.netAmount) - Math.abs(a.netAmount));
+
+    // Separate into who owes you vs who you owe
+    const whoOwesMe = debtSummaries.filter(debt => debt.netAmount < 0).map(debt => ({
+      ...debt,
+      netAmount: Math.abs(debt.netAmount) // Make positive for display
+    }));
+
+    const whoIOwe = debtSummaries.filter(debt => debt.netAmount > 0);
+
+    return json({
+      whoOwesMe,
+      whoIOwe,
+      totalOwedToMe: whoOwesMe.reduce((sum, debt) => sum + debt.netAmount, 0),
+      totalIOwe: whoIOwe.reduce((sum, debt) => sum + debt.netAmount, 0)
+    });
+
+  } catch (e) {
+    console.error('Error calculating debt breakdown:', e);
+    throw error(500, 'Failed to calculate debt breakdown');
+  } finally {
+    await dbDisconnect();
+  }
+};

src/routes/api/cospend/payments/+server.ts

@@ -48,7 +48,7 @@ export const POST: RequestHandler = async ({ request, locals }) => {
     throw error(400, 'Amount must be positive');
   }
 
-  if (!['equal', 'full', 'proportional'].includes(splitMethod)) {
+  if (!['equal', 'full', 'proportional', 'personal_equal'].includes(splitMethod)) {
     throw error(400, 'Invalid split method');
   }
 
@@ -56,6 +56,17 @@ export const POST: RequestHandler = async ({ request, locals }) => {
     throw error(400, 'Invalid category');
   }
 
+  // Validate personal + equal split method
+  if (splitMethod === 'personal_equal' && splits) {
+    const totalPersonal = splits.reduce((sum: number, split: any) => {
+      return sum + (parseFloat(split.personalAmount) || 0);
+    }, 0);
+    
+    if (totalPersonal > amount) {
+      throw error(400, 'Personal amounts cannot exceed total payment amount');
+    }
+  }
+
   await dbConnect();
   
   try {
@@ -77,7 +88,8 @@ export const POST: RequestHandler = async ({ request, locals }) => {
         paymentId: payment._id,
         username: split.username,
         amount: split.amount,
-        proportion: split.proportion
+        proportion: split.proportion,
+        personalAmount: split.personalAmount
       });
     });
 

src/routes/api/cospend/payments/[id]/+server.ts

@@ -75,7 +75,8 @@ export const PUT: RequestHandler = async ({ params, request, locals }) => {
           paymentId: id,
           username: split.username,
           amount: split.amount,
-          proportion: split.proportion
+          proportion: split.proportion,
+          personalAmount: split.personalAmount
         });
       });
 

src/routes/cospend/+page.svelte

@@ -3,6 +3,8 @@
   import { page } from '$app/stores';
   import { pushState } from '$app/navigation';
   import ProfilePicture from '$lib/components/ProfilePicture.svelte';
+  import EnhancedBalance from '$lib/components/EnhancedBalance.svelte';
+  import DebtBreakdown from '$lib/components/DebtBreakdown.svelte';
   import { getCategoryEmoji, getCategoryName } from '$lib/utils/categories';
 
   export let data; // Used by the layout for session data
@@ -67,83 +69,67 @@
     <p>Track and split expenses with your friends and family</p>
   </div>
 
+  <EnhancedBalance />
+
+  <div class="actions">
+    <a href="/cospend/payments/add" class="btn btn-primary">Add Payment</a>
+    <a href="/cospend/payments" class="btn btn-secondary">View All Payments</a>
+  </div>
+
+  <DebtBreakdown />
+
   {#if loading}
-    <div class="loading">Loading your balance...</div>
+    <div class="loading">Loading recent activity...</div>
   {:else if error}
     <div class="error">Error: {error}</div>
-  {:else}
+  {:else if balance.recentSplits && balance.recentSplits.length > 0}
-    <div class="balance-cards">
+    <div class="recent-activity">
-      <div class="balance-card net-balance" class:positive={balance.netBalance <= 0} class:negative={balance.netBalance > 0}>
+      <h2>Recent Activity</h2>
-        <h3>Your Balance</h3>
+      <div class="activity-dialog">
-        <div class="amount">
+        {#each balance.recentSplits as split}
-          {#if balance.netBalance < 0}
+          <div class="activity-message" class:is-me={split.paymentId?.paidBy === data.session?.user?.nickname}>
-            <span class="positive">+{formatCurrency(balance.netBalance)}</span>
+            <div class="message-content">
-            <small>You are owed</small>
+              <ProfilePicture username={split.paymentId?.paidBy || 'Unknown'} size={36} />
-          {:else if balance.netBalance > 0}
+              <a 
-            <span class="negative">-{formatCurrency(balance.netBalance)}</span>
+                href="/cospend/payments/view/{split.paymentId?._id}" 
-            <small>You owe</small>
+                class="activity-bubble"
-          {:else}
+                on:click={(e) => handlePaymentClick(split.paymentId?._id, e)}
-            <span class="even">CHF 0.00</span>
+              >
-            <small>You're all even</small>
+                <div class="activity-header">
-          {/if}
+                  <div class="user-info">
-        </div>
+                    <div class="payment-title-row">
-      </div>
+                      <span class="category-emoji">{getCategoryEmoji(split.paymentId?.category || 'groceries')}</span>
-    </div>
+                      <strong class="payment-title">{split.paymentId?.title || 'Payment'}</strong>
-
-    <div class="actions">
-      <a href="/cospend/payments/add" class="btn btn-primary">Add Payment</a>
-      <a href="/cospend/payments" class="btn btn-secondary">View All Payments</a>
-    </div>
-
-    {#if balance.recentSplits && balance.recentSplits.length > 0}
-      <div class="recent-activity">
-        <h2>Recent Activity</h2>
-        <div class="activity-dialog">
-          {#each balance.recentSplits as split}
-            <div class="activity-message" class:is-me={split.paymentId?.paidBy === data.session?.user?.nickname}>
-              <div class="message-content">
-                <ProfilePicture username={split.paymentId?.paidBy || 'Unknown'} size={36} />
-                <a 
-                  href="/cospend/payments/view/{split.paymentId?._id}" 
-                  class="activity-bubble"
-                  on:click={(e) => handlePaymentClick(split.paymentId?._id, e)}
-                >
-                  <div class="activity-header">
-                    <div class="user-info">
-                      <div class="payment-title-row">
-                        <span class="category-emoji">{getCategoryEmoji(split.paymentId?.category || 'groceries')}</span>
-                        <strong class="payment-title">{split.paymentId?.title || 'Payment'}</strong>
-                      </div>
-                      <span class="username">Paid by {split.paymentId?.paidBy || 'Unknown'}</span>
-                      <span class="category-name">{getCategoryName(split.paymentId?.category || 'groceries')}</span>
-                    </div>
-                    <div class="activity-amount" class:positive={split.amount < 0} class:negative={split.amount > 0}>
-                      {#if split.amount > 0}
-                        -{formatCurrency(split.amount)}
-                      {:else if split.amount < 0}
-                        +{formatCurrency(split.amount)}
-                      {:else}
-                        even
-                      {/if}
                     </div>
+                    <span class="username">Paid by {split.paymentId?.paidBy || 'Unknown'}</span>
+                    <span class="category-name">{getCategoryName(split.paymentId?.category || 'groceries')}</span>
                   </div>
-                  <div class="payment-details">
+                  <div class="activity-amount" class:positive={split.amount < 0} class:negative={split.amount > 0}>
-                    <div class="payment-meta">
+                    {#if split.amount > 0}
-                      <span class="payment-date">{formatDate(split.createdAt)}</span>
+                      -{formatCurrency(split.amount)}
-                    </div>
+                    {:else if split.amount < 0}
-                    {#if split.paymentId?.description}
+                      +{formatCurrency(split.amount)}
-                      <div class="payment-description">
+                    {:else}
-                        {truncateDescription(split.paymentId.description)}
+                      even
-                      </div>
                     {/if}
                   </div>
-                </a>
+                </div>
-              </div>
+                <div class="payment-details">
+                  <div class="payment-meta">
+                    <span class="payment-date">{formatDate(split.createdAt)}</span>
+                  </div>
+                  {#if split.paymentId?.description}
+                    <div class="payment-description">
+                      {truncateDescription(split.paymentId.description)}
+                    </div>
+                  {/if}
+                </div>
+              </a>
             </div>
-          {/each}
+          </div>
-        </div>
+        {/each}
       </div>
-    {/if}
+    </div>
   {/if}
 </main>
 
@@ -182,52 +168,6 @@
     border-radius: 0.5rem;
   }
 
-  .balance-cards {
-    display: flex;
-    justify-content: center;
-    margin-bottom: 2rem;
-  }
-
-  .balance-card {
-    background: white;
-    padding: 2rem;
-    border-radius: 0.75rem;
-    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
-    text-align: center;
-    min-width: 300px;
-  }
-
-  .balance-card.net-balance {
-    background: linear-gradient(135deg, #f5f5f5, #e8e8e8);
-  }
-
-  .balance-card.net-balance.positive {
-    background: linear-gradient(135deg, #e8f5e8, #d4edda);
-  }
-
-  .balance-card.net-balance.negative {
-    background: linear-gradient(135deg, #ffeaea, #f8d7da);
-  }
-
-  .balance-card h3 {
-    margin-bottom: 1rem;
-    color: #555;
-    font-size: 1.1rem;
-  }
-
-  .amount {
-    font-size: 2rem;
-    font-weight: bold;
-    margin-bottom: 0.5rem;
-  }
-
-  .amount small {
-    display: block;
-    font-size: 0.9rem;
-    font-weight: normal;
-    color: #666;
-    margin-top: 0.5rem;
-  }
 
   .positive {
     color: #2e7d32;
@@ -449,11 +389,6 @@
       padding: 1rem;
     }
 
-    .balance-card {
-      min-width: unset;
-      width: 100%;
-    }
-
     .actions {
       flex-direction: column;
       align-items: center;

src/routes/cospend/payments/+page.svelte

@@ -93,6 +93,8 @@
       return `Split equally among ${payment.splits.length} people`;
     } else if (payment.splitMethod === 'full') {
       return `Paid in full by ${payment.paidBy}`;
+    } else if (payment.splitMethod === 'personal_equal') {
+      return `Personal amounts + equal split among ${payment.splits.length} people`;
     } else {
       return `Custom split among ${payment.splits.length} people`;
     }

src/routes/cospend/payments/add/+page.svelte

@@ -2,6 +2,8 @@
   import { onMount } from 'svelte';
   import { goto } from '$app/navigation';
   import { getCategoryOptions } from '$lib/utils/categories';
+  import { PREDEFINED_USERS, isPredefinedUsersMode } from '$lib/config/users';
+  import ProfilePicture from '$lib/components/ProfilePicture.svelte';
   
   export let data;
 
@@ -18,17 +20,34 @@
 
   let imageFile = null;
   let imagePreview = '';
-  let users = [data.session?.user?.nickname || ''];
+  let users = [];
   let newUser = '';
   let splitAmounts = {};
+  let personalAmounts = {};
   let loading = false;
   let error = null;
+  let personalTotalError = false;
+  let predefinedMode = isPredefinedUsersMode();
   
   $: categoryOptions = getCategoryOptions();
 
   onMount(() => {
-    if (data.session?.user?.nickname) {
+    if (predefinedMode) {
-      addSplitForUser(data.session.user.nickname);
+      // Use predefined users and always split between them
+      users = [...PREDEFINED_USERS];
+      users.forEach(user => addSplitForUser(user));
+      // Default to current user as payer if they're in the predefined list
+      if (data.session?.user?.nickname && PREDEFINED_USERS.includes(data.session.user.nickname)) {
+        formData.paidBy = data.session.user.nickname;
+      } else {
+        formData.paidBy = PREDEFINED_USERS[0];
+      }
+    } else {
+      // Original behavior for manual user management
+      if (data.session?.user?.nickname) {
+        users = [data.session.user.nickname];
+        addSplitForUser(data.session.user.nickname);
+      }
     }
   });
 
@@ -61,6 +80,8 @@
   }
 
   function addUser() {
+    if (predefinedMode) return; // No adding users in predefined mode
+    
     if (newUser.trim() && !users.includes(newUser.trim())) {
       users = [...users, newUser.trim()];
       addSplitForUser(newUser.trim());
@@ -69,6 +90,8 @@
   }
 
   function removeUser(userToRemove) {
+    if (predefinedMode) return; // No removing users in predefined mode
+    
     if (users.length > 1 && userToRemove !== data.session.user.nickname) {
       users = users.filter(u => u !== userToRemove);
       delete splitAmounts[userToRemove];
@@ -114,11 +137,42 @@
     splitAmounts = { ...splitAmounts };
   }
 
+  function calculatePersonalEqualSplit() {
+    if (!formData.amount || users.length === 0) return;
+    
+    const totalAmount = parseFloat(formData.amount);
+    
+    // Calculate total personal amounts
+    const totalPersonal = users.reduce((sum, user) => {
+      return sum + (parseFloat(personalAmounts[user]) || 0);
+    }, 0);
+    
+    // Remaining amount to be split equally
+    const remainder = Math.max(0, totalAmount - totalPersonal);
+    const equalShare = remainder / users.length;
+    
+    users.forEach(user => {
+      const personalAmount = parseFloat(personalAmounts[user]) || 0;
+      const totalOwed = personalAmount + equalShare;
+      
+      if (user === formData.paidBy) {
+        // Person who paid gets back what others owe minus what they personally used
+        splitAmounts[user] = totalOwed - totalAmount;
+      } else {
+        // Others owe their personal amount + equal share
+        splitAmounts[user] = totalOwed;
+      }
+    });
+    splitAmounts = { ...splitAmounts };
+  }
+
   function handleSplitMethodChange() {
     if (formData.splitMethod === 'equal') {
       calculateEqualSplits();
     } else if (formData.splitMethod === 'full') {
       calculateFullPayment();
+    } else if (formData.splitMethod === 'personal_equal') {
+      calculatePersonalEqualSplit();
     }
   }
 
@@ -152,6 +206,17 @@
       return;
     }
 
+    // Validate personal amounts for personal_equal split
+    if (formData.splitMethod === 'personal_equal') {
+      const totalPersonal = Object.values(personalAmounts).reduce((sum, val) => sum + (parseFloat(val) || 0), 0);
+      const totalAmount = parseFloat(formData.amount);
+      
+      if (totalPersonal > totalAmount) {
+        error = 'Personal amounts cannot exceed the total payment amount';
+        return;
+      }
+    }
+
     if (users.length === 0) {
       error = 'Please add at least one user to split with';
       return;
@@ -169,7 +234,8 @@
       const splits = users.map(user => ({
         username: user,
         amount: splitAmounts[user] || 0,
-        proportion: formData.splitMethod === 'proportional' ? (splitAmounts[user] || 0) / parseFloat(formData.amount) : undefined
+        proportion: formData.splitMethod === 'proportional' ? (splitAmounts[user] || 0) / parseFloat(formData.amount) : undefined,
+        personalAmount: formData.splitMethod === 'personal_equal' ? (parseFloat(personalAmounts[user]) || 0) : undefined
       }));
 
       const payload = {
@@ -205,6 +271,17 @@
   $: if (formData.amount && formData.splitMethod && formData.paidBy) {
     handleSplitMethodChange();
   }
+
+  // Validate and recalculate when personal amounts change
+  $: if (formData.splitMethod === 'personal_equal' && personalAmounts && formData.amount) {
+    const totalPersonal = Object.values(personalAmounts).reduce((sum, val) => sum + (parseFloat(val) || 0), 0);
+    const totalAmount = parseFloat(formData.amount);
+    personalTotalError = totalPersonal > totalAmount;
+    
+    if (!personalTotalError) {
+      calculatePersonalEqualSplit();
+    }
+  }
 </script>
 
 <svelte:head>
@@ -323,28 +400,46 @@
     <div class="form-section">
       <h2>Split Between Users</h2>
       
-      <div class="users-list">
+      {#if predefinedMode}
-        {#each users as user}
+        <div class="predefined-users">
-          <div class="user-item">
+          <p class="predefined-note">Splitting between predefined users:</p>
-            <span>{user}</span>
+          <div class="users-list">
-            {#if user !== data.session.user.nickname}
+            {#each users as user}
-              <button type="button" class="remove-user" on:click={() => removeUser(user)}>
+              <div class="user-item with-profile">
-                Remove
+                <ProfilePicture username={user} size={32} />
-              </button>
+                <span class="username">{user}</span>
-            {/if}
+                {#if user === data.session?.user?.nickname}
+                  <span class="you-badge">You</span>
+                {/if}
+              </div>
+            {/each}
           </div>
-        {/each}
+        </div>
-      </div>
+      {:else}
+        <div class="users-list">
+          {#each users as user}
+            <div class="user-item with-profile">
+              <ProfilePicture username={user} size={32} />
+              <span class="username">{user}</span>
+              {#if user !== data.session.user.nickname}
+                <button type="button" class="remove-user" on:click={() => removeUser(user)}>
+                  Remove
+                </button>
+              {/if}
+            </div>
+          {/each}
+        </div>
 
-      <div class="add-user">
+        <div class="add-user">
-        <input 
+          <input 
-          type="text" 
+            type="text" 
-          bind:value={newUser} 
+            bind:value={newUser} 
-          placeholder="Add user..."
+            placeholder="Add user..."
-          on:keydown={(e) => e.key === 'Enter' && (e.preventDefault(), addUser())}
+            on:keydown={(e) => e.key === 'Enter' && (e.preventDefault(), addUser())}
-        />
+          />
-        <button type="button" on:click={addUser}>Add User</button>
+          <button type="button" on:click={addUser}>Add User</button>
-      </div>
+        </div>
+      {/if}
     </div>
 
     <div class="form-section">
@@ -353,7 +448,11 @@
       <div class="split-method">
         <label>
           <input type="radio" bind:group={formData.splitMethod} value="equal" />
-          Equal Split
+          {predefinedMode && users.length === 2 ? 'Split 50/50' : 'Equal Split'}
+        </label>
+        <label>
+          <input type="radio" bind:group={formData.splitMethod} value="personal_equal" />
+          Personal + Equal Split
         </label>
         <label>
           <input type="radio" bind:group={formData.splitMethod} value="full" />
@@ -382,12 +481,43 @@
         </div>
       {/if}
 
+      {#if formData.splitMethod === 'personal_equal'}
+        <div class="personal-splits">
+          <h3>Personal Amounts</h3>
+          <p class="description">Enter personal amounts for each user. The remainder will be split equally.</p>
+          {#each users as user}
+            <div class="split-input">
+              <label>{user}</label>
+              <input 
+                type="number" 
+                step="0.01" 
+                min="0"
+                bind:value={personalAmounts[user]}
+                placeholder="0.00"
+              />
+            </div>
+          {/each}
+          {#if formData.amount}
+            <div class="remainder-info" class:error={personalTotalError}>
+              <span>Total Personal: CHF {Object.values(personalAmounts).reduce((sum, val) => sum + (parseFloat(val) || 0), 0).toFixed(2)}</span>
+              <span>Remainder to Split: CHF {Math.max(0, parseFloat(formData.amount) - Object.values(personalAmounts).reduce((sum, val) => sum + (parseFloat(val) || 0), 0)).toFixed(2)}</span>
+              {#if personalTotalError}
+                <div class="error-message">⚠️ Personal amounts exceed total payment amount!</div>
+              {/if}
+            </div>
+          {/if}
+        </div>
+      {/if}
+
       {#if Object.keys(splitAmounts).length > 0}
         <div class="split-preview">
           <h3>Split Preview</h3>
           {#each users as user}
             <div class="split-item">
-              <span>{user}</span>
+              <div class="split-user">
+                <ProfilePicture username={user} size={24} />
+                <span class="username">{user}</span>
+              </div>
               <span class="amount" class:positive={splitAmounts[user] < 0} class:negative={splitAmounts[user] > 0}>
                 {#if splitAmounts[user] > 0}
                   owes CHF {splitAmounts[user].toFixed(2)}
@@ -564,6 +694,37 @@
     border-radius: 1rem;
   }
 
+  .user-item.with-profile {
+    gap: 0.75rem;
+  }
+
+  .user-item .username {
+    font-weight: 500;
+  }
+
+  .you-badge {
+    background-color: #1976d2;
+    color: white;
+    padding: 0.125rem 0.5rem;
+    border-radius: 1rem;
+    font-size: 0.75rem;
+    font-weight: 500;
+  }
+
+  .predefined-users {
+    background-color: #f8f9fa;
+    padding: 1rem;
+    border-radius: 0.5rem;
+    border: 1px solid #e9ecef;
+  }
+
+  .predefined-note {
+    margin: 0 0 1rem 0;
+    color: #666;
+    font-size: 0.9rem;
+    font-style: italic;
+  }
+
   .remove-user {
     background-color: #d32f2f;
     color: white;
@@ -652,6 +813,12 @@
     margin-bottom: 0.5rem;
   }
 
+  .split-user {
+    display: flex;
+    align-items: center;
+    gap: 0.5rem;
+  }
+
   .amount.positive {
     color: #2e7d32;
     font-weight: 500;
@@ -709,6 +876,43 @@
     background-color: #e8e8e8;
   }
 
+  .personal-splits {
+    margin-top: 1rem;
+  }
+
+  .personal-splits .description {
+    color: #666;
+    font-size: 0.9rem;
+    margin-bottom: 1rem;
+    font-style: italic;
+  }
+
+  .remainder-info {
+    margin-top: 1rem;
+    padding: 1rem;
+    background-color: #f8f9fa;
+    border-radius: 0.5rem;
+    border: 1px solid #e9ecef;
+  }
+
+  .remainder-info.error {
+    background-color: #fff5f5;
+    border-color: #fed7d7;
+  }
+
+  .remainder-info span {
+    display: block;
+    margin-bottom: 0.5rem;
+    font-weight: 500;
+  }
+
+  .error-message {
+    color: #d32f2f;
+    font-weight: 600;
+    margin-top: 0.5rem;
+    font-size: 0.9rem;
+  }
+
   @media (max-width: 600px) {
     .add-payment {
       padding: 1rem;

src/routes/cospend/payments/view/[id]/+page.svelte

@@ -47,6 +47,8 @@
       return `Split equally among ${payment.splits.length} people`;
     } else if (payment.splitMethod === 'full') {
       return `Paid in full by ${payment.paidBy}`;
+    } else if (payment.splitMethod === 'personal_equal') {
+      return `Personal amounts + equal split among ${payment.splits.length} people`;
     } else {
       return `Custom split among ${payment.splits.length} people`;
     }