From fe0e1b5e9376a7e5af6030c5b5d40243ec4a1015454e8be3b9bd1ac5323a7362 Mon Sep 17 00:00:00 2001
From: wlfb <thomas.langer@destengs.com>
Date: Mon, 20 Jul 2026 11:23:26 +0200
Subject: [PATCH] feat: deutsche Betragsanzeige (eur-Filter) und deutsche
 GUI-Labels

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
---
 finance/app/formats.py                    | 30 ++++++++++++++++
 finance/app/routers/gui.py                |  3 ++
 finance/app/templates/_preview_table.html |  6 ++--
 finance/app/templates/index.html          | 10 +++---
 finance/app/templates/planning.html       | 39 ++++++++++----------
 finance/app/templates/salden.html         |  8 ++---
 finance/app/templates/transactions.html   |  2 +-
 finance/tests/test_formats.py             | 43 +++++++++++++++++++++++
 finance/tests/test_gui.py                 | 32 ++++++++++++++---
 9 files changed, 138 insertions(+), 35 deletions(-)
 create mode 100644 finance/app/formats.py
 create mode 100644 finance/tests/test_formats.py

diff --git a/finance/app/formats.py b/finance/app/formats.py
new file mode 100644
index 0000000..bf13b7d
--- /dev/null
+++ b/finance/app/formats.py
@@ -0,0 +1,30 @@
+"""Deutsche Anzeige-Formate fuer die GUI (Ausbaustufe 5).
+
+Bewusst ohne locale-Modul: Container-Locales sind nicht garantiert
+installiert, und die Ausgabe hinge sonst vom Host ab. Reine
+Decimal-Formatierung; die JSON-API bleibt Punkt-Dezimal.
+"""
+from decimal import Decimal, ROUND_HALF_UP
+
+DE_LABELS = {
+    "monthly": "monatlich",
+    "quarterly": "vierteljährlich",
+    "yearly": "jährlich",
+    "annuity": "Annuität",
+    "bullet": "endfällig",
+    "percent": "Prozent",
+    "absolute": "Absolut",
+    "remove": "Entfällt",
+    "ende": "Ende",
+}
+
+
+def eur(value) -> str:
+    """Decimal("-2474.5") -> "-2.474,50" (ohne Euro-Zeichen, das setzt das Template)."""
+    d = Decimal(str(value)).quantize(Decimal("0.01"), rounding=ROUND_HALF_UP)
+    s = f"{d:,.2f}"  # US-Trenner: "-2,474.50"
+    return s.replace(",", "\x00").replace(".", ",").replace("\x00", ".")
+
+
+def de_label(value: str) -> str:
+    return DE_LABELS.get(value, value)
diff --git a/finance/app/routers/gui.py b/finance/app/routers/gui.py
index d9ef6c6..da64f84 100644
--- a/finance/app/routers/gui.py
+++ b/finance/app/routers/gui.py
@@ -10,6 +10,7 @@ from app.auth import COOKIE, session_valid
 from app.db import get_session
 from app.engine.loans import add_months
 from app.engine.recurrence import occurrences
+from app.formats import de_label, eur
 from app.models.tables import (Account, Category, PlannedItem,
                                ProjectionResult, RecurringItem,
                                ScenarioLoan, ScenarioModifier, Transaction)
@@ -28,6 +29,8 @@ PAGE_SIZE = 50
 
 templates = Jinja2Templates(directory="app/templates")
 templates.env.globals["app_version"] = get_version()
+templates.env.filters["eur"] = eur
+templates.env.filters["de_label"] = de_label
 router = APIRouter()
 
 
diff --git a/finance/app/templates/_preview_table.html b/finance/app/templates/_preview_table.html
index f0fb513..85bbf33 100644
--- a/finance/app/templates/_preview_table.html
+++ b/finance/app/templates/_preview_table.html
@@ -8,7 +8,7 @@
       <td>{{ tx.booking_date.strftime('%d.%m.%Y') }}</td>
       <td>{{ tx.purpose }}</td>
       <td>{{ tx.counterparty }}</td>
-      <td class="{{ 'neg' if tx.amount < 0 else '' }}">{{ '%.2f'|format(tx.amount) }} €</td>
+      <td class="{{ 'neg' if tx.amount < 0 else '' }}">{{ tx.amount|eur }} €</td>
       <td>{% if tx.is_duplicate %}<span class="badge badge-warning">Duplikat</span>{% endif %}</td>
     </tr>
     {% else %}
@@ -25,7 +25,7 @@
   {% else %}
   <span class="badge badge-error">Saldo-Differenz – bitte prüfen</span>
   {% endif %}
-  · Eröffnungssaldo: {{ '%.2f'|format(statement.opening_balance) if statement.opening_balance is not none else '–' }} €
-  · Endsaldo: {{ '%.2f'|format(statement.closing_balance) if statement.closing_balance is not none else '–' }} €
+  · Eröffnungssaldo: {{ statement.opening_balance|eur if statement.opening_balance is not none else '–' }} €
+  · Endsaldo: {{ statement.closing_balance|eur if statement.closing_balance is not none else '–' }} €
   · Duplikate: {{ duplicates }}
 </p>
diff --git a/finance/app/templates/index.html b/finance/app/templates/index.html
index bcd81c8..c47a71d 100644
--- a/finance/app/templates/index.html
+++ b/finance/app/templates/index.html
@@ -11,7 +11,7 @@
 {% endif %}
 
 <div class="total-balance {{ 'neg' if total < 0 else '' }}">
-  Gesamtsaldo: {{ '%.2f'|format(total) }} €
+  Gesamtsaldo: {{ total|eur }} €
 </div>
 
 <table>
@@ -26,10 +26,10 @@
     <tr>
       <td class="account">{{ account.name }}</td>
       <td>{{ account.bank }}</td>
-      <td class="{{ 'neg' if balance < 0 else '' }}">{{ '%.2f'|format(balance) }} €</td>
+      <td class="{{ 'neg' if balance < 0 else '' }}">{{ balance|eur }} €</td>
       <td>
         {% if account.anchor_date is not none and account.anchor_balance is not none %}
-          Anker: {{ '%.2f'|format(account.anchor_balance) }} € am {{ account.anchor_date.strftime('%d.%m.%Y') }}
+          Anker: {{ account.anchor_balance|eur }} € am {{ account.anchor_date.strftime('%d.%m.%Y') }}
         {% else %}
           kein Anker
         {% endif %}
@@ -47,7 +47,7 @@
           <input type="date" name="anchor_date"
                  value="{{ account.anchor_date.isoformat() if account.anchor_date is not none else '' }}" required>
           <input type="text" name="anchor_balance" placeholder="500.00"
-                 value="{{ account.anchor_balance if account.anchor_balance is not none else '' }}" required>
+                 value="{{ account.anchor_balance|eur if account.anchor_balance is not none else '' }}" required>
           <button type="submit">Anker setzen</button>
         </form>
       </td>
@@ -68,7 +68,7 @@
     <tr>
       <td>{{ item.date.strftime('%d.%m.%Y') }}</td>
       <td>{{ item.name }}</td>
-      <td class="{{ 'neg' if item.amount < 0 else '' }}">{{ '%.2f'|format(item.amount) }} €</td>
+      <td class="{{ 'neg' if item.amount < 0 else '' }}">{{ item.amount|eur }} €</td>
     </tr>
     {% else %}
     <tr><td colspan="3">Keine anstehenden Posten.</td></tr>
diff --git a/finance/app/templates/planning.html b/finance/app/templates/planning.html
index 2877281..e77d5e1 100644
--- a/finance/app/templates/planning.html
+++ b/finance/app/templates/planning.html
@@ -13,8 +13,8 @@
       {% for r in recurring %}
       <tr>
         <td>{{ r.name }}</td>
-        <td class="{{ 'neg' if r.amount < 0 else '' }}">{{ '%.2f'|format(r.amount) }} €</td>
-        <td>{{ r.rhythm }}</td>
+        <td class="{{ 'neg' if r.amount < 0 else '' }}">{{ r.amount|eur }} €</td>
+        <td>{{ r.rhythm|de_label }}</td>
         <td>{{ r.due_day }}</td>
         <td>{{ category_names.get(r.category_id, '–') }}</td>
         <td>
@@ -39,7 +39,7 @@
       <label>Betrag <input type="text" name="amount" placeholder="-49.99" required></label>
       <label>Rhythmus
         <select name="rhythm" data-type="str">
-          {% for rh in rhythms %}<option value="{{ rh }}">{{ rh }}</option>{% endfor %}
+          {% for rh in rhythms %}<option value="{{ rh }}">{{ rh|de_label }}</option>{% endfor %}
         </select>
       </label>
       <label>Fälligkeitstag <input type="number" name="due_day" data-type="int" min="1" max="31" required></label>
@@ -64,8 +64,8 @@
         {% for s in suggestions %}
         <tr>
           <td>{{ s.name }}</td>
-          <td class="{{ 'neg' if s.amount < 0 else '' }}">{{ '%.2f'|format(s.amount) }} €</td>
-          <td>{{ s.rhythm }}</td>
+          <td class="{{ 'neg' if s.amount < 0 else '' }}">{{ s.amount|eur }} €</td>
+          <td>{{ s.rhythm|de_label }}</td>
           <td>{{ s.due_day }}</td>
           <td>
             <form class="inline-form" hx-ext="json-form" hx-post="/api/recurring" hx-swap="none"
@@ -98,7 +98,7 @@
       {% for p in planned %}
       <tr>
         <td>{{ p.name }}</td>
-        <td class="{{ 'neg' if p.amount < 0 else '' }}">{{ '%.2f'|format(p.amount) }} €</td>
+        <td class="{{ 'neg' if p.amount < 0 else '' }}">{{ p.amount|eur }} €</td>
         <td>{{ p.due.strftime('%d.%m.%Y') }}</td>
         <td>{{ category_names.get(p.category_id, '–') }}</td>
         <td>
@@ -143,11 +143,11 @@
       {% for l in loans %}
       <tr>
         <td>{{ l.name }}</td>
-        <td>{{ '%.2f'|format(l.principal) }} €</td>
-        <td>{{ '%.2f'|format(l.annual_rate_pct) }} %</td>
+        <td>{{ l.principal|eur }} €</td>
+        <td>{{ l.annual_rate_pct|eur }} %</td>
         <td>{{ l.term_months }} Monate</td>
         <td>{{ l.payout_date.strftime('%d.%m.%Y') }}</td>
-        <td>{{ l.repayment_type }}</td>
+        <td>{{ l.repayment_type|de_label }}</td>
         <td>
           <form class="inline-form" hx-delete="/api/loans/{{ l.id }}" hx-swap="none"
                 hx-confirm="„{{ l.name }}“ wirklich löschen?"
@@ -181,7 +181,7 @@
       <label>Auszahlungsdatum <input type="date" name="payout_date" required></label>
       <label>Tilgungsart
         <select name="repayment_type" data-type="str">
-          {% for rt in repayment_types %}<option value="{{ rt }}">{{ rt }}</option>{% endfor %}
+          {% for rt in repayment_types %}<option value="{{ rt }}">{{ rt|de_label }}</option>{% endfor %}
         </select>
       </label>
       <button type="submit">Anlegen</button>
@@ -227,8 +227,8 @@
               {% if m.target_type == "category" %}Kategorie: {{ category_names.get(m.target_id, m.target_id) }}
               {% else %}Posten: {{ recurring_names.get(m.target_id, m.target_id) }}{% endif %}
             </td>
-            <td>{{ m.kind }}</td>
-            <td>{{ '%.2f'|format(m.value) }}</td>
+            <td>{{ m.kind|de_label }}</td>
+            <td>{{ m.value|eur }}</td>
             <td>
               <form class="inline-form" hx-delete="/api/scenarios/{{ sc.id }}/modifiers/{{ m.id }}" hx-swap="none"
                     hx-on::after-request="if(event.detail.successful){window.location.reload()}">
@@ -266,7 +266,7 @@
         </span>
         <label>Art
           <select name="kind" data-type="str">
-            {% for k in modifier_kinds %}<option value="{{ k }}">{{ k }}</option>{% endfor %}
+            {% for k in modifier_kinds %}<option value="{{ k }}">{{ k|de_label }}</option>{% endfor %}
           </select>
         </label>
         <label>Wert <input type="text" name="value" value="0"></label>
@@ -281,7 +281,7 @@
 
     {% if row.result %}
     <p>
-      Tiefpunkt: {{ '%.2f'|format(row.result.low_point_balance) }} € am {{ row.result.low_point_date.strftime('%d.%m.%Y') }}<br>
+      Tiefpunkt: {{ row.result.low_point_balance|eur }} € am {{ row.result.low_point_date.strftime('%d.%m.%Y') }}<br>
       {% if row.result.below_zero_date %}Unterschreitet 0 € ab {{ row.result.below_zero_date.strftime('%d.%m.%Y') }}<br>{% endif %}
       {% if row.result.below_threshold_date %}Unterschreitet Warnschwelle ab {{ row.result.below_threshold_date.strftime('%d.%m.%Y') }}<br>{% endif %}
       Kurven in <a href="http://{{ request.url.hostname or '127.0.0.1' }}:8097" target="_blank" rel="noopener">Grafana</a> ansehen.
@@ -343,6 +343,9 @@
     var parts = iso.split('-');
     return parts[2] + '.' + parts[1] + '.' + parts[0];
   }
+  function fmtEur(n) {
+    return Number(n).toLocaleString('de-DE', {minimumFractionDigits: 2, maximumFractionDigits: 2});
+  }
   function loadLoanSchedule(loanId) {
     if (loadedSchedules[loanId]) return;
     loadedSchedules[loanId] = true;
@@ -353,10 +356,10 @@
           + '<th>Tilgung</th><th>Restschuld</th></tr></thead><tbody>';
         rows.forEach(function (r) {
           html += '<tr><td>' + formatIsoDate(r.due) + '</td>'
-            + '<td>' + Number(r.payment).toFixed(2) + ' €</td>'
-            + '<td>' + Number(r.interest).toFixed(2) + ' €</td>'
-            + '<td>' + Number(r.principal).toFixed(2) + ' €</td>'
-            + '<td>' + Number(r.remaining).toFixed(2) + ' €</td></tr>';
+            + '<td>' + fmtEur(r.payment) + ' €</td>'
+            + '<td>' + fmtEur(r.interest) + ' €</td>'
+            + '<td>' + fmtEur(r.principal) + ' €</td>'
+            + '<td>' + fmtEur(r.remaining) + ' €</td></tr>';
         });
         html += '</tbody></table>';
         document.getElementById('schedule-' + loanId).innerHTML = html;
diff --git a/finance/app/templates/salden.html b/finance/app/templates/salden.html
index c3b78d4..670f558 100644
--- a/finance/app/templates/salden.html
+++ b/finance/app/templates/salden.html
@@ -17,14 +17,14 @@
     {% for account, balance in balances %}
     <tr>
       <td class="account">{{ account.name }}</td>
-      <td class="amount {{ 'neg' if balance < 0 else '' }}">{{ '%.2f'|format(balance) }} €</td>
+      <td class="amount {{ 'neg' if balance < 0 else '' }}">{{ balance|eur }} €</td>
     </tr>
     {% else %}
     <tr><td colspan="2">Keine Konten angelegt.</td></tr>
     {% endfor %}
     <tr class="total-row">
       <td><strong>Gesamt</strong></td>
-      <td class="amount {{ 'neg' if total < 0 else '' }}"><strong>{{ '%.2f'|format(total) }} €</strong></td>
+      <td class="amount {{ 'neg' if total < 0 else '' }}"><strong>{{ total|eur }} €</strong></td>
     </tr>
   </tbody>
 </table>
@@ -48,9 +48,9 @@
     <tr data-month="{{ row['month'].isoformat() }}">
       <td>{{ row['month'].strftime('%m.%Y') }}</td>
       {% for account, value in row['values'] %}
-      <td class="amount {{ 'neg' if value < 0 else '' }}">{{ '%.2f'|format(value) }} €</td>
+      <td class="amount {{ 'neg' if value < 0 else '' }}">{{ value|eur }} €</td>
       {% endfor %}
-      <td class="amount {{ 'neg' if row['total'] < 0 else '' }}">{{ '%.2f'|format(row['total']) }} €</td>
+      <td class="amount {{ 'neg' if row['total'] < 0 else '' }}">{{ row['total']|eur }} €</td>
     </tr>
     {% else %}
     <tr><td colspan="{{ accounts|length + 2 }}">Keine bestätigten Buchungen vorhanden.</td></tr>
diff --git a/finance/app/templates/transactions.html b/finance/app/templates/transactions.html
index 65d411c..d83a832 100644
--- a/finance/app/templates/transactions.html
+++ b/finance/app/templates/transactions.html
@@ -53,7 +53,7 @@
       <td class="account">{{ account_names.get(tx.account_id, tx.account_id) }}</td>
       <td>{{ tx.purpose }}</td>
       <td>{{ tx.counterparty }}</td>
-      <td class="amount {{ 'neg' if tx.amount < 0 else '' }}">{{ '%.2f'|format(tx.amount) }}</td>
+      <td class="amount {{ 'neg' if tx.amount < 0 else '' }}">{{ tx.amount|eur }}</td>
       <td>
         <select name="category_id" data-type="int" hx-ext="json-form"
                 hx-patch="/api/transactions/{{ tx.id }}" hx-trigger="change" hx-swap="none">
diff --git a/finance/tests/test_formats.py b/finance/tests/test_formats.py
new file mode 100644
index 0000000..0e01e9a
--- /dev/null
+++ b/finance/tests/test_formats.py
@@ -0,0 +1,43 @@
+from decimal import Decimal
+
+from app.formats import DE_LABELS, de_label, eur
+
+
+def test_eur_basisformat():
+    assert eur(Decimal("2474.00")) == "2.474,00"
+
+
+def test_eur_negativ_mit_mehreren_tausenderpunkten():
+    assert eur(Decimal("-1234567.5")) == "-1.234.567,50"
+
+
+def test_eur_null_und_kleinbetraege():
+    assert eur(Decimal("0")) == "0,00"
+    assert eur(Decimal("-0.5")) == "-0,50"
+    assert eur(Decimal("999.99")) == "999,99"
+
+
+def test_eur_rundung_half_up():
+    assert eur(Decimal("1.005")) == "1,01"
+    assert eur(Decimal("-1.005")) == "-1,01"
+
+
+def test_eur_akzeptiert_strings_und_int():
+    # Templates reichen teils DB-Werte als str/int durch (z.B. Suggestions).
+    assert eur("1234.5") == "1.234,50"
+    assert eur(7) == "7,00"
+
+
+def test_de_label_bekannte_und_unbekannte_werte():
+    assert de_label("monthly") == "monatlich"
+    assert de_label("quarterly") == "vierteljährlich"
+    assert de_label("yearly") == "jährlich"
+    assert de_label("annuity") == "Annuität"
+    assert de_label("bullet") == "endfällig"
+    assert de_label("percent") == "Prozent"
+    assert de_label("absolute") == "Absolut"
+    assert de_label("remove") == "Entfällt"
+    assert de_label("ende") == "Ende"
+    assert de_label("weirdvalue") == "weirdvalue"
+    assert set(DE_LABELS) == {"monthly", "quarterly", "yearly", "annuity",
+                              "bullet", "percent", "absolute", "remove", "ende"}
diff --git a/finance/tests/test_gui.py b/finance/tests/test_gui.py
index b01869d..095643f 100644
--- a/finance/tests/test_gui.py
+++ b/finance/tests/test_gui.py
@@ -1,7 +1,8 @@
 from datetime import date, timedelta
 from decimal import Decimal
 
-from app.models.tables import Account
+from app.formats import eur
+from app.models.tables import Account, RecurringItem
 
 H = {"Authorization": "Bearer test-key"}
 
@@ -34,7 +35,7 @@ def test_index_shows_account_anchor(client, db):
 
     r = client.get("/")
     assert r.status_code == 200
-    assert "Anker: 321.00" in r.text
+    assert "Anker: 321,00" in r.text
     assert "30.06.2026" in r.text
     assert "kein Anker" in r.text
     # Inline-Pflegeformular fuer den Anker muss je Konto vorhanden sein.
@@ -42,6 +43,29 @@ def test_index_shows_account_anchor(client, db):
     assert 'name="anchor_balance"' in r.text
 
 
+def test_gui_zeigt_deutsche_betragsformate(client, db):
+    client.post("/login", data={"username": "admin", "password": "geheim"})
+    acc = Account(bank="dkb", iban="DE-FMT-1", name="Formatkonto", type="giro")
+    db.add(acc)
+    db.flush()
+    acc.anchor_date = date(2026, 6, 30)
+    acc.anchor_balance = Decimal("12345.60")
+    db.commit()
+    r = client.get("/")
+    assert "12.345,60" in r.text
+    assert "12345.60" not in r.text
+
+
+def test_planung_zeigt_deutsche_labels(client, db):
+    client.post("/login", data={"username": "admin", "password": "geheim"})
+    db.add(RecurringItem(name="Miete-Label-Test", amount=Decimal("-600.00"),
+                         rhythm="monthly", due_day=1))
+    db.commit()
+    r = client.get("/planung")
+    assert "monatlich" in r.text
+    assert "-600,00" in r.text
+
+
 def test_import_page_has_dropzone_and_list(client):
     client.post("/login", data={"username": "admin", "password": "geheim"})
     r = client.get("/import")
@@ -234,7 +258,7 @@ def test_salden_page_stichtag_and_month_overview(client, db):
     expected_stichtag = Decimal("1000.00") + Decimal("111.11") + Decimal("22.22")
     r = client.get(f"/salden?stichtag={stichtag.isoformat()}")
     assert r.status_code == 200
-    assert f"{expected_stichtag:.2f}" in r.text
+    assert eur(expected_stichtag) in r.text
 
     # Monatsuebersicht: genau 3 Monatszeilen (m2, m1, m0).
     assert r.text.count('data-month="') == 3
@@ -245,7 +269,7 @@ def test_salden_page_stichtag_and_month_overview(client, db):
     # m2), d.h. NACH Buchung 1 (in m2), aber VOR Buchung 2 (die faellt erst
     # in m1 selbst und darf den Monatsanfang nicht verfaelschen).
     expected_m1_start = Decimal("1000.00") + Decimal("111.11")
-    assert f"{expected_m1_start:.2f}" in r.text
+    assert eur(expected_m1_start) in r.text
 
 
 def test_salden_stichtag_garbage_falls_back_to_today(client):