feat(recurring): a recurring expense paid by someone else is owed to them

CHANGELOG.md

@@ -3,6 +3,13 @@
 Notable changes for people who install the app. Every release, with its installers, is on the
 [releases page](https://github.com/joaoguimaraespro/personal-finance/releases); the full history is in the [commits](https://github.com/joaoguimaraespro/personal-finance/commits/main).
 
+## [Unreleased]
+
+### Added
+
+- Recurring expenses paid by someone else (a flatmate pays the rent): choose *Someone else (I owe them)* and each
+  confirmed occurrence is owed to that person, until you pay them back in Sharing.
+
 ## [1.3.0] - 2026-10-20
 
 ### Changed

backend/tests/Integration.Tests/SharedExpenseTests.cs

@@ -280,6 +280,26 @@ public async Task What_was_owed_before_the_app_is_the_persons_opening_balance()
             .GetDecimal().ShouldBe(0m); // being paid back is not income
     }
 
+    [Fact]
+    public async Task A_recurring_item_paid_by_someone_else_is_owed_to_them_each_time()
+    {
+        var api = await factory.OwnerAsync();
+        var today = DateOnly.FromDateTime(DateTime.UtcNow);
+        var sara = await api.CreateAsync("/api/accounts", new { name = "Sara (pays the rent)", kind = "Person", currency = "EUR", openingBalance = 0m });
+        var recurringId = await api.CreateAsync("/api/recurring", new
+        {
+            name = "My part of the rent", type = "Expense", amount = 300m, accountId = sara, frequency = "Monthly",
+            startOn = today.ToString("yyyy-MM-dd"), dayOfMonth = today.Day, categoryId = SystemCatalog.CategoryId("housing"),
+        });
+        var proposal = (await api.GetAsync<JsonElement[]>("/api/expected"))
+            .Single(p => p.GetProperty("recurringTransactionId").GetGuid() == recurringId);
+        await ApiClient.EnsureAsync(await api.PostAsync($"/api/expected/{proposal.GetProperty("id").GetGuid()}/confirm", new { }));
+
+        var person = await PersonAsync(api, sara);
+        person.GetProperty("balance").GetDecimal().ShouldBe(-300m); // the owner owes it
+        person.GetProperty("recent").EnumerateArray().Single().GetProperty("kind").GetString().ShouldBe("theyPaid");
+    }
+
     private static async Task<decimal> GetIncomeAsync(ApiClient api) =>
         (await api.GetJsonAsync("/api/reports/monthly/2053-07")).GetProperty("current").GetProperty("income").GetDecimal();
 }

web/public/i18n/en.json

@@ -384,7 +384,13 @@
   "active": "Active",
   "paused": "Paused",
   "shareHint": "Each time it is confirmed, they owe their part of what was paid — the split follows the amount when the bill varies.",
-  "confirmValue": "{{name}}: value to confirm"
+  "confirmValue": "{{name}}: value to confirm",
+  "whoPays": "Who pays it",
+  "paidByMe": "I do",
+  "paidByPerson": "Someone else (I owe them)",
+  "paidByWho": "Paid by",
+  "paidByHint": "Each time it is confirmed you owe them this amount (your part), until you pay them back in Sharing. Nothing leaves your accounts.",
+  "paidByName": "paid by {{name}}"
  },
  "budgets": {
   "subtitle": "Each version applies from its month onwards — changing it never rewrites past months.",

web/public/i18n/pt-PT.json

@@ -384,7 +384,13 @@
   "active": "Ativo",
   "paused": "Em pausa",
   "shareHint": "Sempre que for confirmado, ficam a dever a parte deles do que foi pago — a divisão acompanha o valor quando a conta varia.",
-  "confirmValue": "{{name}}: quantia a confirmar"
+  "confirmValue": "{{name}}: quantia a confirmar",
+  "whoPays": "Quem paga",
+  "paidByMe": "Eu",
+  "paidByPerson": "Outra pessoa (fico a dever)",
+  "paidByWho": "Pago por",
+  "paidByHint": "Sempre que for confirmado ficas a dever-lhe este valor (a tua parte), até lhe pagares em Partilhas. Não sai dinheiro das tuas contas.",
+  "paidByName": "paga por {{name}}"
  },
  "budgets": {
   "subtitle": "Cada versão aplica-se a partir do seu mês — alterá-la nunca reescreve meses anteriores.",

web/src/app/features/recurring/recurring.ts

@@ -61,6 +61,8 @@ interface Form {
   sharePeople: string[];
   shareEqual: boolean;
   shareAmounts: Record<string, string>;
+  /** Paid by another person each time (the owner owes it to them): that person's id, '' when the owner pays. */
+  paidBy: string;
 }
 
 @Component({
@@ -157,6 +159,12 @@ interface Form {
                   } @else {
                     {{ categoryFor(r.categoryId) | categoryLabel }}
                   }
+                  @if (paidByOf(r); as who) {
+                    ·
+                    <span class="text-violet-700 dark:text-violet-300">{{
+                      'recurring.paidByName' | translate: { name: who }
+                    }}</span>
+                  }
                   @if (r.shares?.length) {
                     ·
                     <span class="text-violet-700 dark:text-violet-300">{{
@@ -341,17 +349,54 @@ interface Form {
             <app-field-error [error]="fs.errors().bucketId" />
           </div>
         }
-        <div class="col-span-2">
-          <label class="label" for="r-acc">{{ 'tx.account' | translate }}</label>
-          <app-select
-            inputId="r-acc"
-            [options]="accountOptions()"
-            [value]="form().accountId"
-            (valueChange)="fs.touch('accountId'); patch({ accountId: $event })"
-            [attr.aria-invalid]="!!fs.errors().accountId || null"
-          />
-          <app-field-error [error]="fs.errors().accountId" />
-        </div>
+        @if (form().type === 'Expense' && people().length) {
+          <!-- Someone else pays it each time (a flatmate pays the rent): the owner owes them, nothing leaves an account. -->
+          <div class="col-span-2">
+            <p class="label">{{ 'recurring.whoPays' | translate }}</p>
+            <div
+              class="segmented text-xs"
+              role="group"
+              [attr.aria-label]="'recurring.whoPays' | translate"
+            >
+              <button type="button" [class.active]="!form().paidBy" (click)="patch({ paidBy: '' })">
+                {{ 'recurring.paidByMe' | translate }}
+              </button>
+              <button
+                type="button"
+                [class.active]="!!form().paidBy"
+                (click)="patch({ paidBy: form().paidBy || people()[0].id, sharePeople: [] })"
+              >
+                {{ 'recurring.paidByPerson' | translate }}
+              </button>
+            </div>
+          </div>
+        }
+        @if (form().paidBy) {
+          <div class="col-span-2">
+            <label class="label" for="r-paid-by">{{ 'recurring.paidByWho' | translate }}</label>
+            <app-select
+              inputId="r-paid-by"
+              [options]="personOptions()"
+              [value]="form().paidBy"
+              (valueChange)="patch({ paidBy: $event })"
+            />
+            <p class="mt-1 text-xs text-muted-foreground">
+              {{ 'recurring.paidByHint' | translate }}
+            </p>
+          </div>
+        } @else {
+          <div class="col-span-2">
+            <label class="label" for="r-acc">{{ 'tx.account' | translate }}</label>
+            <app-select
+              inputId="r-acc"
+              [options]="accountOptions()"
+              [value]="form().accountId"
+              (valueChange)="fs.touch('accountId'); patch({ accountId: $event })"
+              [attr.aria-invalid]="!!fs.errors().accountId || null"
+            />
+            <app-field-error [error]="fs.errors().accountId" />
+          </div>
+        }
         @if (canShare()) {
           <!-- Shared with people (ADR-0011): each confirmed occurrence owes them their part of what was paid. -->
           <div class="col-span-2 rounded-lg border p-3">
@@ -535,8 +580,17 @@ export class RecurringComponent {
     this.people().filter((p) => this.form().sharePeople.includes(p.id)),
   );
   protected readonly canShare = computed(
-    () => this.form().type === 'Expense' && !this.form().splits && this.people().length > 0,
+    () =>
+      this.form().type === 'Expense' &&
+      !this.form().splits &&
+      !this.form().paidBy &&
+      this.people().length > 0,
+  );
+  protected readonly personOptions = computed(() =>
+    this.people().map((p) => ({ value: p.id, label: p.name })),
   );
+  /** The person who pays an item for the owner, when it is one of them. */
+  protected paidByOf = (r: Recurring) => this.people().find((p) => p.id === r.accountId)?.name;
   protected shareNames = (r: Recurring) =>
     (r.shares ?? [])
       .map((s) => this.people().find((p) => p.id === s.personId)?.name)
@@ -638,7 +692,10 @@ export class RecurringComponent {
             name: r.name,
             type: r.type,
             amount: String(r.amount),
-            accountId: r.accountId,
+            accountId: this.people().some((p) => p.id === r.accountId)
+              ? (this.manualAccounts()[0]?.id ?? '')
+              : r.accountId,
+            paidBy: this.people().some((p) => p.id === r.accountId) ? r.accountId : '',
             categoryId: r.categoryId ?? '',
             bucketId: r.bucketId ?? '',
             frequency: r.frequency,
@@ -669,7 +726,7 @@ export class RecurringComponent {
     const valid = this.fs.check({
       name: rules.required(f.name),
       amount: rules.positive(parseAmount(f.amount)),
-      accountId: rules.pick(f.accountId),
+      accountId: f.paidBy ? undefined : rules.pick(f.accountId),
       categoryId: everyday && !split ? rules.pick(f.categoryId) : undefined,
       bucketId: !everyday && f.type !== 'Transfer' ? rules.pick(f.bucketId) : undefined,
       interval:
@@ -700,7 +757,8 @@ export class RecurringComponent {
       type: f.type,
       amount: parseAmount(f.amount),
       currency: 'EUR',
-      accountId: f.accountId,
+      // Paid by someone else: the expense is booked in that person's account (the owner owes it to them).
+      accountId: f.type === 'Expense' && f.paidBy ? f.paidBy : f.accountId,
       ...scheduleBody(f),
       startOn: f.startOn,
       endOn: f.endOn || null,
@@ -771,6 +829,7 @@ export class RecurringComponent {
       sharePeople: [],
       shareEqual: true,
       shareAmounts: {},
+      paidBy: '',
     };
   }
 }