feat: add Wochenübersicht export + ICD import auto-detect

- New Excel export service for weekly DAK summary sheets (c2s / c2s_g_s variants)
- New API endpoint GET /reports/wochenuebersicht (admin-only)
- ICD import auto-detects format (coding template vs. Wochenübersicht KVNR-based)
- New admin frontend page with download form
- Route + sidebar navigation entry

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

backend/app/api/reports.py

@@ -2,6 +2,7 @@
 
 import logging
 import os
+from collections import defaultdict
 from datetime import date
 from io import BytesIO
 
@@ -283,6 +284,81 @@ def delete_reports(
     return {"deleted": deleted}
 
 
+@router.get("/wochenuebersicht")
+def download_wochenuebersicht(
+    export_type: str = Query(...),
+    jahr: int = Query(...),
+    kw_von: int = Query(...),
+    kw_bis: int = Query(...),
+    db: Session = Depends(get_db),
+    user: User = Depends(require_admin),
+):
+    """Generate and download a Wochenübersicht Excel file for DAK.
+
+    Admin only. Returns an .xlsx file with weekly case summaries grouped by KW.
+    """
+    from app.config import get_settings
+    from app.models.case import Case
+    from app.services.wochenuebersicht_export import (
+        WOCHENUEBERSICHT_TYPES,
+        generate_wochenuebersicht_xlsx,
+    )
+
+    settings = get_settings()
+
+    if export_type not in WOCHENUEBERSICHT_TYPES:
+        raise HTTPException(422, f"Unknown export_type: {export_type}")
+    if not (1 <= kw_von <= 53 and 1 <= kw_bis <= 53):
+        raise HTTPException(422, "kw_von and kw_bis must be between 1 and 53")
+    if kw_von > kw_bis:
+        raise HTTPException(422, "kw_von must be <= kw_bis")
+
+    type_cfg = WOCHENUEBERSICHT_TYPES[export_type]
+    fallgruppen = type_cfg["fallgruppen"]
+
+    cases = (
+        db.query(Case)
+        .filter(
+            Case.jahr == jahr,
+            Case.kw >= kw_von,
+            Case.kw <= kw_bis,
+            Case.fallgruppe.in_(fallgruppen),
+            Case.versicherung == settings.VERSICHERUNG_FILTER,
+        )
+        .order_by(Case.kw, Case.datum)
+        .all()
+    )
+
+    cases_by_kw: dict[int, list[Case]] = defaultdict(list)
+    for case in cases:
+        cases_by_kw[case.kw].append(case)
+
+    xlsx_bytes = generate_wochenuebersicht_xlsx(cases_by_kw, export_type, jahr)
+
+    infix = type_cfg["filename_infix"]
+    filename = f"Wochenübersicht {infix} KW{kw_bis:02d}{jahr % 100:02d}.xlsx"
+
+    log_action(
+        db,
+        user_id=user.id,
+        action="wochenuebersicht_downloaded",
+        entity_type="report",
+        new_values={
+            "export_type": export_type,
+            "jahr": jahr,
+            "kw_von": kw_von,
+            "kw_bis": kw_bis,
+            "case_count": len(cases),
+        },
+    )
+
+    return StreamingResponse(
+        BytesIO(xlsx_bytes),
+        media_type="application/vnd.openxmlformats-officedocument.spreadsheetml.sheet",
+        headers={"Content-Disposition": f'attachment; filename="{filename}"'},
+    )
+
+
 @router.get("/list", response_model=ReportListResponse)
 def list_reports(
     db: Session = Depends(get_db),

backend/app/services/icd_service.py

@@ -143,14 +143,50 @@ def generate_coding_template(
 
 
 def import_icd_from_xlsx(db: Session, content: bytes, user_id: int) -> dict:
-    """Import ICD codes from a filled-in coding template Excel file.
+    """Import ICD codes from an Excel file.
+
+    Auto-detects the format:
+      - Coding template: Column A contains numeric Case_IDs
+      - Wochenübersicht: Column A contains KVNR strings (letter prefix)
 
-    Expects columns: Case_ID (col 1), ICD (last col — col 5 or col 7)
     Returns: {"updated": int, "errors": list[str]}
     """
     wb = load_workbook(BytesIO(content), read_only=True)
     ws = wb.active
 
+    # Detect format by scanning for first data row
+    detected_format = _detect_import_format(ws)
+
+    if detected_format == "wochenuebersicht":
+        return _import_icd_wochenuebersicht(db, ws, user_id)
+
+    # Default: Coding template (Case_ID-based)
+    return _import_icd_coding_template(db, ws, user_id)
+
+
+def _detect_import_format(ws) -> str:
+    """Detect whether the worksheet is a coding template or Wochenübersicht."""
+    for row in ws.iter_rows(min_row=1, max_row=20, values_only=True):
+        if not row or not row[0]:
+            continue
+        val = str(row[0]).strip()
+        # Skip header rows
+        if val.lower() in ("case_id", "kvnr", "kalenderwoche:"):
+            continue
+        # If it's a pure integer, it's a coding template (Case_ID)
+        try:
+            int(val)
+            return "coding_template"
+        except (ValueError, TypeError):
+            pass
+        # If it starts with a letter, it's likely a KVNR → Wochenübersicht
+        if val and val[0].isalpha():
+            return "wochenuebersicht"
+    return "coding_template"
+
+
+def _import_icd_coding_template(db: Session, ws, user_id: int) -> dict:
+    """Import ICD codes from a coding template (Case_ID in column A)."""
     updated = 0
     errors: list[str] = []
 
@@ -180,3 +216,63 @@ def import_icd_from_xlsx(db: Session, content: bytes, user_id: int) -> dict:
             errors.append(f"Case {case_id}: {e}")
 
     return {"updated": updated, "errors": errors}
+
+
+def _import_icd_wochenuebersicht(db: Session, ws, user_id: int) -> dict:
+    """Import ICD codes from a Wochenübersicht file (KVNR in col A, ICD in col I)."""
+    updated = 0
+    errors: list[str] = []
+
+    for row in ws.iter_rows(values_only=False):
+        # Skip rows without enough columns
+        if len(row) < 9:
+            continue
+
+        col_a = row[0].value
+        if not col_a:
+            continue
+
+        col_a_str = str(col_a).strip()
+
+        # Skip header/label rows
+        if col_a_str.lower() in ("kvnr", ""):
+            continue
+        # Skip non-data rows (e.g. "Kalenderwoche:", instruction text)
+        if not col_a_str[0].isalpha() and not col_a_str[0].isdigit():
+            continue
+        # Skip rows where col A looks like a header label
+        if col_a_str.lower().startswith(("bitte", "kalender")):
+            continue
+
+        kvnr = col_a_str
+
+        # ICD is in column I (index 8)
+        icd_cell = row[8].value
+        if not icd_cell:
+            continue
+        icd_value = str(icd_cell).strip()
+        if not icd_value or icd_value.lower() == "icd-10":
+            continue
+
+        # Find case by KVNR — take the most recent one
+        case = (
+            db.query(Case)
+            .filter(
+                Case.kvnr == kvnr,
+                Case.versicherung == settings.VERSICHERUNG_FILTER,
+            )
+            .order_by(Case.datum.desc())
+            .first()
+        )
+
+        if not case:
+            errors.append(f"KVNR {kvnr}: Kein Fall gefunden")
+            continue
+
+        try:
+            save_icd_for_case(db, case.id, icd_value, user_id)
+            updated += 1
+        except Exception as e:
+            errors.append(f"KVNR {kvnr} (Case {case.id}): {e}")
+
+    return {"updated": updated, "errors": errors}

backend/app/services/wochenuebersicht_export.py

@@ -0,0 +1,193 @@
+"""Wochenübersicht Excel export for DAK weekly summary sheets.
+
+Generates .xlsx files matching the format sent to DAK for ICD code entry.
+Two variants exist:
+  - "c2s"     → Fallgruppen onko + intensiv (columns ZMO / ZMI)
+  - "c2s_g_s" → Fallgruppen galle + sd     (columns Galle / Schild)
+
+Each KW block has 4 header rows + data rows + 2 blank separator rows.
+KWs are sorted descending (newest first).
+"""
+
+from __future__ import annotations
+
+from datetime import date
+from io import BytesIO
+from typing import Any
+
+from openpyxl import Workbook
+from openpyxl.styles import Alignment, Border, Font, PatternFill, Side
+
+from app.services.excel_export import HEADER_FILL, HEADER_FONT
+
+# ---------------------------------------------------------------------------
+# Type configuration
+# ---------------------------------------------------------------------------
+
+WOCHENUEBERSICHT_TYPES: dict[str, dict[str, Any]] = {
+    "c2s": {
+        "fallgruppen": ("onko", "intensiv"),
+        "fg_labels": ("ZMO", "ZMI"),
+        "filename_infix": "c2s",
+    },
+    "c2s_g_s": {
+        "fallgruppen": ("galle", "sd"),
+        "fg_labels": ("Galle", "Schild"),
+        "filename_infix": "c2s_g_s",
+    },
+}
+
+# Column headers (row 4 of each KW block)
+COL_HEADERS = [
+    "KVNR",                                          # A
+    "Datum",                                          # B
+    "Erstgespräch",                                   # C
+    "Zweitmeinung/Vorbereitung (bei Abbruch)",        # D
+    "Zweitmeinung/Vorbereitung + Erteilung",          # E
+    "Schriftliche Dokumentation (Gutachten)",          # F
+    # G and H are dynamic (FG labels)
+    # I = ICD-10
+]
+
+THIN_BORDER = Border(
+    left=Side(style="thin"),
+    right=Side(style="thin"),
+    top=Side(style="thin"),
+    bottom=Side(style="thin"),
+)
+
+
+def _kw_date_range(jahr: int, kw: int) -> tuple[date, date]:
+    """Return (Monday, Sunday) for the given ISO year/week."""
+    monday = date.fromisocalendar(jahr, kw, 1)
+    sunday = date.fromisocalendar(jahr, kw, 7)
+    return monday, sunday
+
+
+def _format_date_range(monday: date, sunday: date) -> str:
+    """Format as 'DD.MM. - DD.MM.YYYY'."""
+    return f"{monday.strftime('%d.%m.')} - {sunday.strftime('%d.%m.%Y')}"
+
+
+def generate_wochenuebersicht_xlsx(
+    cases_by_kw: dict[int, list[Any]],
+    export_type: str,
+    jahr: int,
+) -> bytes:
+    """Generate a Wochenübersicht Excel workbook.
+
+    Args:
+        cases_by_kw: Cases grouped by calendar week number.
+        export_type: One of ``"c2s"`` or ``"c2s_g_s"``.
+        jahr: The report year.
+
+    Returns:
+        The ``.xlsx`` file contents as bytes.
+    """
+    type_cfg = WOCHENUEBERSICHT_TYPES[export_type]
+    fg1, fg2 = type_cfg["fallgruppen"]
+    fg1_label, fg2_label = type_cfg["fg_labels"]
+
+    wb = Workbook()
+    ws = wb.active
+    ws.title = "Wochenübersicht"
+
+    # Column widths
+    ws.column_dimensions["A"].width = 14
+    ws.column_dimensions["B"].width = 12
+    ws.column_dimensions["C"].width = 14
+    ws.column_dimensions["D"].width = 18
+    ws.column_dimensions["E"].width = 18
+    ws.column_dimensions["F"].width = 16
+    ws.column_dimensions["G"].width = 10
+    ws.column_dimensions["H"].width = 10
+    ws.column_dimensions["I"].width = 14
+
+    current_row = 1
+
+    # Sort KWs descending (newest first)
+    sorted_kws = sorted(cases_by_kw.keys(), reverse=True)
+
+    for kw in sorted_kws:
+        cases = cases_by_kw[kw]
+        monday, sunday = _kw_date_range(jahr, kw)
+
+        # --- Row 1: "Kalenderwoche:" label + number ---
+        ws.cell(row=current_row, column=5, value="Kalenderwoche:")
+        ws.cell(row=current_row, column=5).font = HEADER_FONT
+        ws.cell(row=current_row, column=6, value=kw)
+        ws.cell(row=current_row, column=6).font = HEADER_FONT
+        current_row += 1
+
+        # --- Row 2: Date range ---
+        ws.cell(row=current_row, column=5, value=_format_date_range(monday, sunday))
+        ws.cell(row=current_row, column=5).font = Font(italic=True)
+        current_row += 1
+
+        # --- Row 3: Instruction ---
+        ws.cell(
+            row=current_row,
+            column=3,
+            value="Bitte entsprechendes Feld mit x kennzeichnen",
+        )
+        ws.cell(row=current_row, column=3).font = Font(italic=True, color="FF808080")
+        current_row += 1
+
+        # --- Row 4: Column headers ---
+        headers = COL_HEADERS + [fg1_label, fg2_label, "ICD-10"]
+        for ci, header in enumerate(headers, start=1):
+            cell = ws.cell(row=current_row, column=ci, value=header)
+            cell.fill = HEADER_FILL
+            cell.font = HEADER_FONT
+            cell.border = THIN_BORDER
+            cell.alignment = Alignment(wrap_text=True, vertical="center")
+        current_row += 1
+
+        # --- Data rows ---
+        # Sort cases by datum ascending within each KW
+        sorted_cases = sorted(cases, key=lambda c: (c.datum or date.min))
+
+        for case in sorted_cases:
+            # A: KVNR
+            ws.cell(row=current_row, column=1, value=case.kvnr or "")
+            # B: Datum
+            ws.cell(
+                row=current_row,
+                column=2,
+                value=case.datum.strftime("%d.%m.%Y") if case.datum else "",
+            )
+            # C: Erstgespräch — always x
+            ws.cell(row=current_row, column=3, value="x")
+            # D: Zweitmeinung/Vorbereitung (bei Abbruch)
+            if case.ablehnung or case.abbruch:
+                ws.cell(row=current_row, column=4, value="x")
+            # E: Zweitmeinung/Vorbereitung + Erteilung
+            if case.unterlagen and not case.ablehnung and not case.abbruch:
+                ws.cell(row=current_row, column=5, value="x")
+            # F: Schriftliche Dokumentation (Gutachten)
+            if case.gutachten:
+                ws.cell(row=current_row, column=6, value="x")
+            # G: FG1 (ZMO / Galle)
+            if case.fallgruppe == fg1:
+                ws.cell(row=current_row, column=7, value="x")
+            # H: FG2 (ZMI / Schild)
+            if case.fallgruppe == fg2:
+                ws.cell(row=current_row, column=8, value="x")
+            # I: ICD-10
+            ws.cell(row=current_row, column=9, value=case.icd or "")
+
+            # Apply thin borders to data row
+            for ci in range(1, 10):
+                ws.cell(row=current_row, column=ci).border = THIN_BORDER
+                ws.cell(row=current_row, column=ci).alignment = Alignment(
+                    horizontal="center" if ci >= 3 else "left"
+                )
+
+            current_row += 1
+
+        # --- 2 blank separator rows ---
+        current_row += 2
+
+    buf = BytesIO()
+    wb.save(buf)
+    return buf.getvalue()

frontend/src/App.tsx

@@ -18,6 +18,7 @@ import { DisclosuresPage } from '@/pages/DisclosuresPage'
 import { AccountPage } from '@/pages/AccountPage'
 import { GutachtenStatistikPage } from '@/pages/GutachtenStatistikPage'
 import { MyDisclosuresPage } from '@/pages/MyDisclosuresPage'
+import { WochenuebersichtPage } from '@/pages/WochenuebersichtPage'
 
 const queryClient = new QueryClient({
   defaultOptions: {
@@ -45,6 +46,7 @@ function App() {
               <Route path="icd" element={<IcdPage />} />
               <Route path="coding" element={<ProtectedRoute requireAdmin><CodingPage /></ProtectedRoute>} />
               <Route path="reports" element={<ReportsPage />} />
+              <Route path="wochenuebersicht" element={<ProtectedRoute requireAdmin><WochenuebersichtPage /></ProtectedRoute>} />
               <Route path="gutachten-statistik" element={<GutachtenStatistikPage />} />
               <Route path="account" element={<AccountPage />} />
               <Route path="disclosures" element={<MyDisclosuresPage />} />

frontend/src/components/layout/Sidebar.tsx

@@ -10,6 +10,7 @@ import {
   FileEdit,
   ClipboardCheck,
   FileBarChart,
+  FileOutput,
   Users,
   Mail,
   History,
@@ -32,6 +33,7 @@ const mainNavItems: NavItem[] = [
   { label: 'ICD-Eingabe', to: '/icd', icon: FileEdit, mitarbeiterOnly: true },
   { label: 'Coding', to: '/coding', icon: ClipboardCheck, adminOnly: true },
   { label: 'Berichte', to: '/reports', icon: FileBarChart },
+  { label: 'Wochenübersicht', to: '/wochenuebersicht', icon: FileOutput, adminOnly: true },
 ]
 
 const accountNavItems: NavItem[] = [

frontend/src/pages/WochenuebersichtPage.tsx

@@ -0,0 +1,177 @@
+import { useState } from 'react'
+import { Download, FileSpreadsheet, Loader2 } from 'lucide-react'
+import api from '@/services/api'
+import { Button } from '@/components/ui/button'
+import { Card, CardContent, CardHeader, CardTitle } from '@/components/ui/card'
+import { Input } from '@/components/ui/input'
+import { Label } from '@/components/ui/label'
+import {
+  Select, SelectContent, SelectItem, SelectTrigger, SelectValue,
+} from '@/components/ui/select'
+import { Alert, AlertDescription } from '@/components/ui/alert'
+
+const EXPORT_TYPES = [
+  { value: 'c2s', label: 'Onko-Intensiv (c2s)' },
+  { value: 'c2s_g_s', label: 'Galle-Schild (c2s_g_s)' },
+] as const
+
+function getISOWeek(d: Date): number {
+  const date = new Date(Date.UTC(d.getFullYear(), d.getMonth(), d.getDate()))
+  const dayNum = date.getUTCDay() || 7
+  date.setUTCDate(date.getUTCDate() + 4 - dayNum)
+  const yearStart = new Date(Date.UTC(date.getUTCFullYear(), 0, 1))
+  return Math.ceil(((date.getTime() - yearStart.getTime()) / 86_400_000 + 1) / 7)
+}
+
+export function WochenuebersichtPage() {
+  const currentYear = new Date().getFullYear()
+  const currentKw = getISOWeek(new Date())
+
+  const [jahr, setJahr] = useState(currentYear)
+  const [kwVon, setKwVon] = useState(1)
+  const [kwBis, setKwBis] = useState(currentKw)
+  const [exportType, setExportType] = useState('c2s')
+  const [loading, setLoading] = useState(false)
+  const [error, setError] = useState('')
+  const [success, setSuccess] = useState('')
+
+  const handleDownload = async () => {
+    setError('')
+    setSuccess('')
+
+    if (kwVon > kwBis) {
+      setError('KW von darf nicht größer als KW bis sein.')
+      return
+    }
+
+    setLoading(true)
+    try {
+      const res = await api.get('/reports/wochenuebersicht', {
+        params: { export_type: exportType, jahr, kw_von: kwVon, kw_bis: kwBis },
+        responseType: 'blob',
+      })
+
+      const blob = new Blob([res.data as BlobPart], {
+        type: 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet',
+      })
+      const blobUrl = window.URL.createObjectURL(blob)
+      const link = document.createElement('a')
+      link.href = blobUrl
+
+      const contentDisposition = res.headers['content-disposition']
+      let filename = `Wochenuebersicht_${exportType}_KW${kwBis}_${jahr}.xlsx`
+      if (contentDisposition) {
+        const match = contentDisposition.match(/filename[^;=\n]*=((['"]).*?\2|[^;\n]*)/)
+        if (match) filename = match[1].replace(/['"]/g, '')
+      }
+
+      link.download = filename
+      document.body.appendChild(link)
+      link.click()
+      document.body.removeChild(link)
+      window.URL.revokeObjectURL(blobUrl)
+      setSuccess(`Wochenübersicht KW ${kwVon}–${kwBis}/${jahr} wurde heruntergeladen.`)
+    } catch {
+      setError('Fehler beim Herunterladen der Wochenübersicht.')
+    } finally {
+      setLoading(false)
+    }
+  }
+
+  return (
+    <div className="p-6 space-y-6">
+      <h1 className="text-2xl font-bold">Wochenübersicht</h1>
+
+      <Card>
+        <CardHeader>
+          <CardTitle className="text-lg flex items-center gap-2">
+            <FileSpreadsheet className="h-5 w-5" />
+            Wochenübersicht für die DAK generieren
+          </CardTitle>
+        </CardHeader>
+        <CardContent className="space-y-4">
+          <p className="text-sm text-muted-foreground">
+            Erstellt eine Excel-Datei mit den Falldaten pro Kalenderwoche,
+            die an die DAK zur ICD-Code-Eingabe gesendet wird.
+          </p>
+
+          <div className="flex flex-wrap items-end gap-4">
+            <div className="space-y-1">
+              <Label htmlFor="wu-jahr">Jahr</Label>
+              <Input
+                id="wu-jahr"
+                type="number"
+                value={jahr}
+                onChange={(e) => setJahr(Number(e.target.value))}
+                className="w-28"
+                min={2020}
+                max={2030}
+              />
+            </div>
+            <div className="space-y-1">
+              <Label htmlFor="wu-kw-von">KW von</Label>
+              <Input
+                id="wu-kw-von"
+                type="number"
+                value={kwVon}
+                onChange={(e) => setKwVon(Number(e.target.value))}
+                className="w-24"
+                min={1}
+                max={53}
+              />
+            </div>
+            <div className="space-y-1">
+              <Label htmlFor="wu-kw-bis">KW bis</Label>
+              <Input
+                id="wu-kw-bis"
+                type="number"
+                value={kwBis}
+                onChange={(e) => setKwBis(Number(e.target.value))}
+                className="w-24"
+                min={1}
+                max={53}
+              />
+            </div>
+            <div className="space-y-1">
+              <Label>Exporttyp</Label>
+              <Select value={exportType} onValueChange={setExportType}>
+                <SelectTrigger className="w-52">
+                  <SelectValue />
+                </SelectTrigger>
+                <SelectContent>
+                  {EXPORT_TYPES.map((t) => (
+                    <SelectItem key={t.value} value={t.value}>{t.label}</SelectItem>
+                  ))}
+                </SelectContent>
+              </Select>
+            </div>
+            <Button onClick={handleDownload} disabled={loading}>
+              {loading ? (
+                <>
+                  <Loader2 className="mr-2 h-4 w-4 animate-spin" />
+                  Wird generiert...
+                </>
+              ) : (
+                <>
+                  <Download className="mr-2 h-4 w-4" />
+                  Herunterladen
+                </>
+              )}
+            </Button>
+          </div>
+
+          {error && (
+            <Alert variant="destructive">
+              <AlertDescription>{error}</AlertDescription>
+            </Alert>
+          )}
+          {success && (
+            <Alert>
+              <AlertDescription>{success}</AlertDescription>
+            </Alert>
+          )}
+        </CardContent>
+      </Card>
+    </div>
+  )
+}