feat: first test implementation for substitution system

backend/database.go

@@ -99,6 +99,17 @@ func createTables(db *sql.DB) {
 			is_active BOOLEAN NOT NULL DEFAULT 0,
 			created_at DATETIME DEFAULT CURRENT_TIMESTAMP
 		)`,
+		`CREATE TABLE IF NOT EXISTS substitutions (
+			id INTEGER PRIMARY KEY AUTOINCREMENT,
+			date TEXT NOT NULL,
+			start_time TEXT NOT NULL,
+			end_time TEXT NOT NULL,
+			title TEXT NOT NULL,
+			notes TEXT,
+			taken_by_user_id INTEGER,
+			created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
+			FOREIGN KEY(taken_by_user_id) REFERENCES users(id)
+		)`,
 	}
 
 	for _, query := range queries {
@@ -114,6 +125,7 @@ func createIndexes(db *sql.DB) {
 		"CREATE UNIQUE INDEX IF NOT EXISTS idx_users_username ON users(username)",
 		"CREATE INDEX IF NOT EXISTS idx_time_entries_user_date ON time_entries(user_id, date)",
 		"CREATE INDEX IF NOT EXISTS idx_schedules_day ON schedules(day_of_week)",
+		`CREATE INDEX IF NOT EXISTS idx_substitutions_date ON substitutions(date)`,
 	}
 	for _, idx := range indexes {
 		db.Exec(idx)
@@ -577,15 +589,16 @@ func CreateManualTimeEntry(db *sql.DB, entry *TimeEntry, hours float64) error {
 }
 
 func calculateHours(entry TimeEntry) float64 {
-	if entry.Type == "lesson" {
+	switch entry.Type {
+	case "lesson":
 		return 1.0
-	} else if entry.Type == "manual" {
+	case "manual":
 		hours, err := strconv.ParseFloat(entry.StartTime, 64)
 		if err != nil {
 			return 0
 		}
 		return hours
-	} else {
+	default:
 		return calculateHoursDiff(entry.StartTime, entry.EndTime)
 	}
 }
@@ -633,3 +646,107 @@ func DeleteNonManualTimeEntriesByUserAndWeek(db *sql.DB, userID int, year int, w
 	_, err := db.Exec(query, userID, dateList[0], dateList[1], dateList[2], dateList[3], dateList[4])
 	return err
 }
+
+func CreateSubstitution(db *sql.DB, date, start, end, title, notes string) error {
+	_, err := db.Exec(`
+		INSERT INTO substitutions (date, start_time, end_time, title, notes)
+		VALUES (?, ?, ?, ?, ?)
+	`, date, start, end, title, notes)
+	return err
+}
+
+func GetOpenSubstitutions(db *sql.DB) ([]Substitution, error) {
+	rows, err := db.Query(`
+		SELECT id, date, start_time, end_time, title, notes, created_at
+		FROM substitutions
+		WHERE taken_by_user_id IS NULL
+		AND date >= date('now') 
+		ORDER BY date ASC, start_time ASC
+	`)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	var subs []Substitution
+	for rows.Next() {
+		var s Substitution
+		if err := rows.Scan(&s.ID, &s.Date, &s.StartTime, &s.EndTime, &s.Title, &s.Notes, &s.CreatedAt); err != nil {
+			continue
+		}
+		subs = append(subs, s)
+	}
+	return subs, nil
+}
+
+func AcceptSubstitution(db *sql.DB, substitutionID int, userID int) error {
+	tx, err := db.Begin()
+	if err != nil {
+		return err
+	}
+	defer tx.Rollback()
+
+	var currentDate, start, end, title string
+	err = tx.QueryRow(`
+		SELECT date, start_time, end_time, title 
+		FROM substitutions 
+		WHERE id = ? AND taken_by_user_id IS NULL
+	`, substitutionID).Scan(&currentDate, &start, &end, &title)
+
+	if err == sql.ErrNoRows {
+		return fmt.Errorf("Vertretung wurde bereits vergeben oder existiert nicht")
+	}
+	if err != nil {
+		return err
+	}
+
+	_, err = tx.Exec(`
+		UPDATE substitutions 
+		SET taken_by_user_id = ? 
+		WHERE id = ?
+	`, userID, substitutionID)
+	if err != nil {
+		return err
+	}
+
+	_, err = tx.Exec(`
+		INSERT INTO time_entries (user_id, schedule_id, date, type, start_time, end_time)
+		VALUES (?, 0, ?, 'lesson', ?, ?)
+	`, userID, currentDate, start, end)
+	if err != nil {
+		return err
+	}
+
+	return tx.Commit()
+}
+
+func GetAllSubstitutions(db *sql.DB) ([]Substitution, error) {
+	rows, err := db.Query(`
+		SELECT s.id, s.date, s.start_time, s.end_time, s.title, s.notes, s.taken_by_user_id, u.username
+		FROM substitutions s
+		LEFT JOIN users u ON s.taken_by_user_id = u.id
+		ORDER BY s.date DESC
+	`)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	var subs []Substitution
+	for rows.Next() {
+		var s Substitution
+		var takenID sql.NullInt64
+		var takenName sql.NullString
+
+		if err := rows.Scan(&s.ID, &s.Date, &s.StartTime, &s.EndTime, &s.Title, &s.Notes, &takenID, &takenName); err != nil {
+			continue
+		}
+		if takenID.Valid {
+			id := int(takenID.Int64)
+			s.TakenByUserID = &id
+			s.TakenByUsername = takenName.String
+		}
+		subs = append(subs, s)
+	}
+	return subs, nil
+}

backend/go.mod

@@ -3,7 +3,9 @@ module school-timetracker
 go 1.25.3
 
 require (
+	github.com/golang-jwt/jwt/v5 v5.3.0
 	github.com/jung-kurt/gofpdf v1.16.2
+	github.com/labstack/echo-jwt/v4 v4.3.1
 	github.com/labstack/echo/v4 v4.13.4
 	golang.org/x/crypto v0.43.0
 	golang.org/x/time v0.11.0
@@ -12,9 +14,7 @@ require (
 
 require (
 	github.com/dustin/go-humanize v1.0.1 // indirect
-	github.com/golang-jwt/jwt/v5 v5.3.0 // indirect
 	github.com/google/uuid v1.6.0 // indirect
-	github.com/labstack/echo-jwt/v4 v4.3.1 // indirect
 	github.com/labstack/gommon v0.4.2 // indirect
 	github.com/mattn/go-colorable v0.1.14 // indirect
 	github.com/mattn/go-isatty v0.0.20 // indirect

backend/handlers.go

@@ -71,6 +71,16 @@ func (app *App) LoginHandler(c echo.Context) error {
 		return HandleError(c, ErrInvalidCredentialsMsg())
 	}
 
+	if !user.IsAdmin {
+		_, err := VerifyLicenseFile()
+		if err != nil {
+			return c.JSON(http.StatusForbidden, map[string]string{
+				"error": "Lizenzfehler: " + err.Error(),
+				"code":  "LICENSE_INVALID",
+			})
+		}
+
+	}
 	token, err := createToken(user.ID, user.Username, user.IsAdmin)
 	if err != nil {
 		return HandleError(c, ErrInternalMsg(err))
@@ -799,3 +809,106 @@ func (app *App) UploadLogoHandler(c echo.Context) error {
 
 	return c.JSON(http.StatusOK, map[string]string{"message": "Logo erfolgreich hochgeladen"})
 }
+
+func (app *App) GetLicenseStatusHandler(c echo.Context) error {
+	var count int
+	app.DB.QueryRow("SELECT COUNT(*) FROM users").Scan(&count)
+
+	status := GetCurrentLicenseStatus(nil)
+	status.UserCount = count
+
+	if status.IsValid && status.MaxUsers > 0 && count > status.MaxUsers {
+		status.IsValid = false
+		status.Message = fmt.Sprintf("Benutzerlimit überschritten (%d / %d)", count, status.MaxUsers)
+	}
+
+	return c.JSON(http.StatusOK, status)
+}
+
+func (app *App) UploadLicenseHandler(c echo.Context) error {
+	file, err := c.FormFile("license")
+	if err != nil {
+		return HandleError(c, ErrInvalidInputMsg("Keine Datei"))
+	}
+
+	src, err := file.Open()
+	if err != nil {
+		return HandleError(c, ErrInternalMsg(err))
+	}
+	defer src.Close()
+
+	dst, err := os.Create("license.lic")
+	if err != nil {
+		return HandleError(c, ErrInternalMsg(err))
+	}
+	defer dst.Close()
+
+	if _, err = io.Copy(dst, src); err != nil {
+		return HandleError(c, ErrInternalMsg(err))
+	}
+
+	if _, err := VerifyLicenseFile(); err != nil {
+		return c.JSON(http.StatusOK, map[string]string{"message": "Lizenz hochgeladen, aber ungültig: " + err.Error()})
+	}
+
+	return c.JSON(http.StatusOK, map[string]string{"message": "Lizenz erfolgreich aktiviert"})
+}
+
+func (app *App) CreateSubstitutionHandler(c echo.Context) error {
+	var req CreateSubstitutionRequest
+	if err := c.Bind(&req); err != nil {
+		return HandleError(c, ErrInvalidInputMsg("Eingabedaten"))
+	}
+	if req.Date == "" || req.StartTime == "" || req.Title == "" {
+		return HandleError(c, ErrMissingFieldMsg("Pflichtfelder"))
+	}
+
+	if err := CreateSubstitution(app.DB, req.Date, req.StartTime, req.EndTime, req.Title, req.Notes); err != nil {
+		return HandleError(c, ErrDatabaseMsg(err))
+	}
+
+	return c.JSON(http.StatusCreated, map[string]string{"message": "Vertretung ausgeschrieben"})
+}
+
+func (app *App) GetAllSubstitutionsHandler(c echo.Context) error {
+	subs, err := GetAllSubstitutions(app.DB)
+	if err != nil {
+		return HandleError(c, ErrDatabaseMsg(err))
+	}
+	if subs == nil {
+		subs = []Substitution{}
+	}
+	return c.JSON(http.StatusOK, subs)
+}
+
+func (app *App) GetOpenSubstitutionsHandler(c echo.Context) error {
+	subs, err := GetOpenSubstitutions(app.DB)
+	if err != nil {
+		return HandleError(c, ErrDatabaseMsg(err))
+	}
+	if subs == nil {
+		subs = []Substitution{}
+	}
+	return c.JSON(http.StatusOK, subs)
+}
+
+func (app *App) AcceptSubstitutionHandler(c echo.Context) error {
+	claims, err := getClaims(c)
+	if err != nil {
+		return HandleError(c, ErrUnauthorizedMsg())
+	}
+
+	id, err := strconv.Atoi(c.Param("id"))
+	if err != nil {
+		return HandleError(c, ErrInvalidInputMsg("ID"))
+	}
+
+	if err := AcceptSubstitution(app.DB, id, claims.UserID); err != nil {
+		if err.Error() == "Vertretung wurde bereits vergeben oder existiert nicht" {
+			return HandleError(c, ErrAlreadyExistsMsg("Diese Vertretung ist leider schon vergeben"))
+		}
+		return HandleError(c, ErrDatabaseMsg(err))
+	}
+
+	return c.JSON(http.StatusOK, map[string]string{"message": "Vertretung erfolgreich übernommen!"})
+}

backend/license.go

@@ -0,0 +1,72 @@
+package main
+
+import (
+	"crypto/ed25519"
+	"encoding/base64"
+	"encoding/hex"
+	"encoding/json"
+	"fmt"
+	"os"
+	"time"
+)
+
+const PublicKeyHex = "ab8287380d4f26b66b3e8067e179a2e304dcb3c4070963edd213cca9b225978f"
+
+func VerifyLicenseFile() (*LicenseData, error) {
+	bytes, err := os.ReadFile("license.lic")
+	if err != nil {
+		return nil, fmt.Errorf("Keine Lizenzdatei gefunden")
+	}
+
+	var lic LicenseFile
+	if err := json.Unmarshal(bytes, &lic); err != nil {
+		return nil, fmt.Errorf("Lizenzdatei beschädigt")
+	}
+
+	pubBytes, _ := hex.DecodeString(PublicKeyHex)
+	publicKey := ed25519.PublicKey(pubBytes)
+
+	dataBytes, _ := json.Marshal(lic.Data)
+	sigBytes, err := base64.StdEncoding.DecodeString(lic.Signature)
+	if err != nil {
+		return nil, fmt.Errorf("Signatur ungültig")
+	}
+
+	if !ed25519.Verify(publicKey, dataBytes, sigBytes) {
+		return nil, fmt.Errorf("Lizenz-Signatur ungültig (Manipuliert?)")
+	}
+
+	expiry, err := time.Parse("2006-01-02", lic.Data.ExpiresAt)
+	if err != nil {
+		return nil, fmt.Errorf("Ungültiges Datumsformat")
+	}
+	if time.Now().After(expiry) {
+		return &lic.Data, fmt.Errorf("Lizenz abgelaufen am %s", lic.Data.ExpiresAt)
+	}
+
+	return &lic.Data, nil
+}
+
+func GetCurrentLicenseStatus(db *any) LicenseStatus {
+	lic, err := VerifyLicenseFile()
+	status := LicenseStatus{
+		IsValid: err == nil,
+		Message: "Gültig",
+	}
+
+	if err != nil {
+		status.Message = err.Error()
+		if lic != nil {
+			status.SchoolName = lic.SchoolName
+			status.ExpiresAt = lic.ExpiresAt
+			status.MaxUsers = lic.MaxUsers
+		}
+		return status
+	}
+
+	status.SchoolName = lic.SchoolName
+	status.ExpiresAt = lic.ExpiresAt
+	status.MaxUsers = lic.MaxUsers
+
+	return status
+}

backend/main.go

@@ -70,6 +70,8 @@ func main() {
 		protected.GET("/my-info", app.GetMyInfoHandler)
 		protected.POST("/change-password", app.ChangeMyPasswordHandler)
 		protected.GET("/school-year/active", app.GetActiveSchoolYearHandler)
+		protected.GET("/substitutions/open", app.GetOpenSubstitutionsHandler)
+		protected.POST("/substitutions/:id/accept", app.AcceptSubstitutionHandler)
 	}
 
 	admin := e.Group("/api/admin")
@@ -94,6 +96,10 @@ func main() {
 		admin.PUT("/school-years/:id/activate", app.SetActiveSchoolYearHandler)
 		admin.GET("/yearly-summary/pdf", app.GenerateYearlySummaryPDFHandler)
 		admin.POST("/settings/logo", app.UploadLogoHandler)
+		admin.GET("/settings/license", app.GetLicenseStatusHandler)
+		admin.POST("/settings/license", app.UploadLicenseHandler)
+		admin.GET("/substitutions", app.GetAllSubstitutionsHandler)
+		admin.POST("/substitutions", app.CreateSubstitutionHandler)
 	}
 
 	distDir, err := fs.Sub(frontendDist, "dist")

backend/models.go

@@ -106,3 +106,43 @@ type ChangePasswordRequest struct {
 	OldPassword string `json:"old_password"`
 	NewPassword string `json:"new_password"`
 }
+
+type LicenseData struct {
+	SchoolName string `json:"school_name"`
+	MaxUsers   int    `json:"max_users"`
+	ExpiresAt  string `json:"expires_at"`
+}
+
+type LicenseFile struct {
+	Data      LicenseData `json:"data"`
+	Signature string      `json:"signature"`
+}
+
+type LicenseStatus struct {
+	IsValid    bool   `json:"is_valid"`
+	SchoolName string `json:"school_name"`
+	ExpiresAt  string `json:"expires_at"`
+	MaxUsers   int    `json:"max_users"`
+	UserCount  int    `json:"user_count"`
+	Message    string `json:"message"`
+}
+
+type Substitution struct {
+	ID              int       `json:"id"`
+	Date            string    `json:"date"`
+	StartTime       string    `json:"start_time"`
+	EndTime         string    `json:"end_time"`
+	Title           string    `json:"title"`
+	Notes           string    `json:"notes"`
+	TakenByUserID   *int      `json:"taken_by_user_id,omitempty"`
+	TakenByUsername string    `json:"taken_by_username,omitempty"`
+	CreatedAt       time.Time `json:"created_at"`
+}
+
+type CreateSubstitutionRequest struct {
+	Date      string `json:"date" validate:"required"`
+	StartTime string `json:"start_time" validate:"required"`
+	EndTime   string `json:"end_time" validate:"required"`
+	Title     string `json:"title" validate:"required"`
+	Notes     string `json:"notes"`
+}

frontend/src/components/AdminDashboard.svelte

@@ -7,6 +7,7 @@
     import AdminTimeEntriesTab from "./admin/AdminTimeEntriesTab.svelte";
     import AdminSchoolYearsTab from "./admin/AdminSchoolYearsTab.svelte";
     import AdminSettingsTab from "./admin/AdminSettingsTab.svelte";
+    import AdminSubstitutionsTab from "./admin/AdminSubstitutionsTab.svelte";
 
     let activeTab = "schedule";
     const user = $auth.user;
@@ -25,6 +26,8 @@
                 return "Schuljahre & Perioden";
             case "settings":
                 return "Einstellungen";
+            case "substitutions":
+                return "Vertretungen";
             default:
                 return "Admin";
         }
@@ -121,6 +124,8 @@
                 <AdminSchoolYearsTab />
             {:else if activeTab === "settings"}
                 <AdminSettingsTab />
+            {:else if activeTab === "substitutions"}
+                <AdminSubstitutionsTab />
             {/if}
         </div>
     </div>
@@ -277,6 +282,32 @@
                         Schuljahre
                     </button>
                 </li>
+                <li>
+                    <button
+                        class={activeTab === "substitutions"
+                            ? "active bg-primary/10 text-primary"
+                            : ""}
+                        on:click={() => {
+                            activeTab = "substitutions";
+                            closeDrawer();
+                        }}
+                    >
+                        <svg
+                            xmlns="http://www.w3.org/2000/svg"
+                            fill="none"
+                            viewBox="0 0 24 24"
+                            stroke-width="1.5"
+                            stroke="currentColor"
+                            class="w-5 h-5"
+                            ><path
+                                stroke-linecap="round"
+                                stroke-linejoin="round"
+                                d="M6.75 3v2.25M17.25 3v2.25M3 18.75V7.5a2.25 2.25 0 012.25-2.25h13.5A2.25 2.25 0 0121 7.5v11.25m-18 0A2.25 2.25 0 005.25 21h13.5A2.25 2.25 0 0021 18.75m-18 0v-7.5A2.25 2.25 0 015.25 9h13.5A2.25 2.25 0 0121 11.25v7.5"
+                            /></svg
+                        >
+                        Vertretungen
+                    </button>
+                </li>
                 <li
                     class="menu-title opacity-50 uppercase text-xs font-bold tracking-wider mt-4 mb-1"
                 >

frontend/src/components/UserDashboard.svelte

@@ -9,6 +9,8 @@
     deleteWeekEntries,
     changeMyPassword,
     getMyInfo,
+    getOpenSubstitutions,
+    acceptSubstitution,
   } from "../lib/api";
   import {
     getISOWeek,
@@ -36,6 +38,10 @@
   let showPwModal = false;
   let pwData = { old: "", new1: "", new2: "" };
 
+  // State für die Ansicht
+  let activeView = "schedule";
+  let openSubstitutions = [];
+
   $: hasEntriesForWeek = existingEntries.some((e) => e.entryType !== "manual");
 
   $: weekDates = Array.from({ length: 5 }, (_, i) => {
@@ -77,6 +83,8 @@
       await deleteWeekEntries(currentISOYear, currentWeek);
       addToast("Woche erfolgreich zurückgesetzt", "success");
       weekEditMode = false;
+      selectedEntries = [];
+      existingEntries = [];
       await loadData();
     } catch (e) {
       console.error(e);
@@ -88,13 +96,16 @@
   async function loadData() {
     isLoadingData = true;
     try {
-      const [schedulesData, entriesData, userData] = await Promise.all([
+      const [schedulesData, entriesData, userData, subsData] =
-        getSchedules(),
+        await Promise.all([
-        getMyTimeEntries(),
+          getSchedules(),
-        getMyInfo(),
+          getMyTimeEntries(),
-      ]);
+          getMyInfo(),
+          getOpenSubstitutions(),
+        ]);
       schedules = schedulesData;
       allEntries = entriesData;
+      openSubstitutions = subsData;
 
       auth.update((current) => ({
         ...current,
@@ -107,6 +118,37 @@
     }
   }
 
+  async function handleAcceptSub(sub) {
+    if (
+      !confirm(
+        `Möchten Sie die Vertretung "${sub.title}" am ${sub.date} übernehmen?`,
+      )
+    )
+      return;
+
+    try {
+      await acceptSubstitution(sub.id);
+      addToast("Erfolgreich übernommen! Stunden wurden gebucht.", "success");
+      await loadData();
+    } catch (e) {
+      console.error(e);
+    }
+  }
+
+  function jumpToWeekOfDate(dateStr) {
+    const [y, m, d] = dateStr.split("-").map(Number);
+    const targetDate = new Date(y, m - 1, d);
+
+    const targetWeek = getISOWeek(targetDate);
+    const targetYear = getISOYear(targetDate);
+
+    currentISOYear = targetYear;
+    currentWeek = targetWeek;
+
+    activeView = "schedule";
+    loadData();
+  }
+
   function filterEntries(entries) {
     existingEntries = entries.filter((e) => {
       const [y, m, d] = e.date.split("-").map(Number);
@@ -221,10 +263,14 @@
         <div class="text-sm breadcrumbs hidden sm:block">
           <ul>
             <li class="opacity-50">Mein Bereich</li>
-            <li class="font-bold text-primary">Stundenplan</li>
+            <li class="font-bold text-primary">
+              {activeView === "schedule" ? "Stundenplan" : "Vertretungsbörse"}
+            </li>
           </ul>
         </div>
-        <span class="font-bold text-lg sm:hidden">KW {currentWeek}</span>
+        <span class="font-bold text-lg sm:hidden">
+          {activeView === "schedule" ? `KW ${currentWeek}` : "Vertretungen"}
+        </span>
       </div>
 
       <div class="flex-none flex items-center gap-4">
@@ -259,263 +305,346 @@
     </div>
 
     <div class="p-4 md:p-8 lg:p-10 fade-in space-y-6">
-      <div class="card bg-base-100 shadow-sm border border-base-200">
+      {#if activeView === "schedule"}
-        <div class="card-body p-2 sm:p-4 flex-row items-center justify-between">
+        <div class="card bg-base-100 shadow-sm border border-base-200">
-          <button
+          <div
-            class="btn btn-circle btn-ghost"
+            class="card-body p-2 sm:p-4 flex-row items-center justify-between"
-            on:click={() => changeWeek(-1)}
-            disabled={isLoadingData}
           >
-            <svg
+            <button
-              xmlns="http://www.w3.org/2000/svg"
+              class="btn btn-circle btn-ghost"
-              fill="none"
+              on:click={() => changeWeek(-1)}
-              viewBox="0 0 24 24"
+              disabled={isLoadingData}
-              stroke-width="1.5"
-              stroke="currentColor"
-              class="w-6 h-6"
-              ><path
-                stroke-linecap="round"
-                stroke-linejoin="round"
-                d="M15.75 19.5L8.25 12l7.5-7.5"
-              /></svg
             >
-          </button>
+              <svg
-          <div class="text-center">
+                xmlns="http://www.w3.org/2000/svg"
-            <p
+                fill="none"
-              class="text-[10px] sm:text-xs font-bold text-primary tracking-widest uppercase mb-1"
+                viewBox="0 0 24 24"
+                stroke-width="1.5"
+                stroke="currentColor"
+                class="w-6 h-6"
+                ><path
+                  stroke-linecap="round"
+                  stroke-linejoin="round"
+                  d="M15.75 19.5L8.25 12l7.5-7.5"
+                /></svg
+              >
+            </button>
+            <div class="text-center">
+              <p
+                class="text-[10px] sm:text-xs font-bold text-primary tracking-widest uppercase mb-1"
+              >
+                Kalenderwoche
+              </p>
+              <h2 class="text-xl sm:text-3xl font-bold">
+                KW {currentWeek} <span class="text-base-content/30">/</span>
+                {currentISOYear}
+              </h2>
+              <p
+                class="text-xs sm:text-sm opacity-60 mt-1 font-mono bg-base-200 inline-block px-2 py-1 rounded"
+              >
+                {weekDates[0]?.date} — {weekDates[4]?.date}
+              </p>
+            </div>
+            <button
+              class="btn btn-circle btn-ghost"
+              on:click={() => changeWeek(1)}
+              disabled={isLoadingData}
             >
-              Kalenderwoche
+              <svg
-            </p>
+                xmlns="http://www.w3.org/2000/svg"
-            <h2 class="text-xl sm:text-3xl font-bold">
+                fill="none"
-              KW {currentWeek} <span class="text-base-content/30">/</span>
+                viewBox="0 0 24 24"
-              {currentISOYear}
+                stroke-width="1.5"
-            </h2>
+                stroke="currentColor"
-            <p
+                class="w-6 h-6"
-              class="text-xs sm:text-sm opacity-60 mt-1 font-mono bg-base-200 inline-block px-2 py-1 rounded"
+                ><path
-            >
+                  stroke-linecap="round"
-              {weekDates[0]?.date} — {weekDates[4]?.date}
+                  stroke-linejoin="round"
-            </p>
+                  d="M8.25 4.5l7.5 7.5-7.5 7.5"
+                /></svg
+              >
+            </button>
           </div>
-          <button
-            class="btn btn-circle btn-ghost"
-            on:click={() => changeWeek(1)}
-            disabled={isLoadingData}
-          >
-            <svg
-              xmlns="http://www.w3.org/2000/svg"
-              fill="none"
-              viewBox="0 0 24 24"
-              stroke-width="1.5"
-              stroke="currentColor"
-              class="w-6 h-6"
-              ><path
-                stroke-linecap="round"
-                stroke-linejoin="round"
-                d="M8.25 4.5l7.5 7.5-7.5 7.5"
-              /></svg
-            >
-          </button>
         </div>
-      </div>
 
-      <div class="lg:hidden grid grid-cols-2 gap-2">
+        <div class="lg:hidden grid grid-cols-2 gap-2">
-        <div class="stats shadow-sm bg-base-100 border border-base-200 py-1">
+          <div class="stats shadow-sm bg-base-100 border border-base-200 py-1">
-          <div class="stat p-2 text-center">
+            <div class="stat p-2 text-center">
-            <div class="stat-desc">Geleistet</div>
+              <div class="stat-desc">Geleistet</div>
-            <div class="stat-value text-lg">{yearlyTotal.toFixed(1)}</div>
+              <div class="stat-value text-lg">{yearlyTotal.toFixed(1)}</div>
+            </div>
           </div>
-        </div>
+          <div class="stats shadow-sm bg-base-100 border border-base-200 py-1">
-        <div class="stats shadow-sm bg-base-100 border border-base-200 py-1">
+            <div class="stat p-2 text-center">
-          <div class="stat p-2 text-center">
+              <div class="stat-desc">Offen</div>
-            <div class="stat-desc">Offen</div>
+              <div
-            <div
+                class="stat-value text-lg {remaining <= 0
-              class="stat-value text-lg {remaining <= 0
+                  ? 'text-success'
-                ? 'text-success'
+                  : 'text-warning'}"
-                : 'text-warning'}"
+              >
-            >
+                {Math.max(0, remaining).toFixed(1)}
-              {Math.max(0, remaining).toFixed(1)}
+              </div>
             </div>
           </div>
         </div>
-      </div>
 
-      {#if isLoadingData}
+        {#if isLoadingData}
-        <div
+          <div
-          class="hidden lg:block bg-base-100 rounded-2xl p-4 shadow-xl border border-base-200"
+            class="hidden lg:block bg-base-100 rounded-2xl p-4 shadow-xl border border-base-200"
-        >
+          >
-          <div class="flex gap-4">
+            <div class="flex gap-4">
+              {#each Array(5) as _}
+                <div class="flex-1 space-y-4">
+                  <div class="skeleton h-8 w-full mb-4"></div>
+                  <div class="skeleton h-20 w-full rounded"></div>
+                  <div class="skeleton h-20 w-full rounded"></div>
+                </div>
+              {/each}
+            </div>
+          </div>
+          <div class="lg:hidden space-y-4">
             {#each Array(5) as _}
-              <div class="flex-1 space-y-4">
+              <div class="skeleton h-16 w-full rounded-lg"></div>
-                <div class="skeleton h-8 w-full mb-4"></div>
+            {/each}
-                <div class="skeleton h-20 w-full rounded"></div>
+          </div>
-                <div class="skeleton h-20 w-full rounded"></div>
+        {:else}
+          {#if hasEntriesForWeek && !weekEditMode}
+            <div role="alert" class="alert alert-success shadow-sm">
+              <svg
+                xmlns="http://www.w3.org/2000/svg"
+                class="stroke-current shrink-0 h-6 w-6"
+                fill="none"
+                viewBox="0 0 24 24"
+                ><path
+                  stroke-linecap="round"
+                  stroke-linejoin="round"
+                  stroke-width="2"
+                  d="M9 12l2 2 4-4m6 2a9 9 0 11-18 0 9 9 0 0118 0z"
+                /></svg
+              >
+              <div>
+                <h3 class="font-bold">Erfasst!</h3>
+                <div class="text-xs">Stunden gespeichert.</div>
+              </div>
+              <button
+                class="btn btn-sm btn-outline"
+                on:click={() => (weekEditMode = true)}
+                disabled={processing}>Bearbeiten</button
+              >
+            </div>
+          {:else if weekEditMode}
+            <div role="alert" class="alert alert-warning shadow-sm">
+              <svg
+                xmlns="http://www.w3.org/2000/svg"
+                class="stroke-current shrink-0 h-6 w-6"
+                fill="none"
+                viewBox="0 0 24 24"
+                ><path
+                  stroke-linecap="round"
+                  stroke-linejoin="round"
+                  stroke-width="2"
+                  d="M12 9v2m0 4h.01m-6.938 4h13.856c1.54 0 2.502-1.667 1.732-3L13.732 4c-.77-1.333-2.694-1.333-3.464 0L3.34 16c-.77 1.333.192 3 1.732 3z"
+                /></svg
+              >
+              <div>
+                <h3 class="font-bold">Bearbeitungsmodus</h3>
+                <div class="text-xs">Speichern nicht vergessen!</div>
+              </div>
+              <div class="flex gap-2">
+                <button
+                  class="btn btn-sm btn-error"
+                  on:click={handleDeleteWeek}
+                  disabled={processing}>Löschen</button
+                >
+                <button
+                  class="btn btn-sm btn-ghost"
+                  on:click={() => (weekEditMode = false)}>Abbrechen</button
+                >
+              </div>
+            </div>
+          {:else}
+            <div role="alert" class="alert alert-info shadow-sm">
+              <svg
+                xmlns="http://www.w3.org/2000/svg"
+                fill="none"
+                viewBox="0 0 24 24"
+                class="stroke-current shrink-0 w-6 h-6"
+                ><path
+                  stroke-linecap="round"
+                  stroke-linejoin="round"
+                  stroke-width="2"
+                  d="M13 16h-1v-4h-1m1-4h.01M21 12a9 9 0 11-18 0 9 9 0 0118 0z"
+                ></path></svg
+              >
+              <div>
+                <h3 class="font-bold">Zeiterfassung</h3>
+                <div class="text-xs">Wählen Sie Ihre Stunden.</div>
+              </div>
+            </div>
+          {/if}
+
+          <div
+            class="overflow-x-auto hidden lg:block bg-base-100 rounded-2xl shadow-xl border border-base-200"
+          >
+            <table class="table table-fixed w-full">
+              <thead>
+                <tr>
+                  {#each weekDates as day}
+                    <th class="text-center bg-base-200/50 py-4">
+                      <div class="font-bold text-lg">{day.name}</div>
+                      <div class="text-xs font-normal opacity-50">
+                        {day.date}
+                      </div>
+                    </th>
+                  {/each}
+                </tr>
+              </thead>
+              <tbody>
+                <tr>
+                  {#each weekDates as day}
+                    <td
+                      class="align-top p-2 min-w-[160px] border-r border-base-200 last:border-0"
+                    >
+                      <div class="space-y-2">
+                        {#each schedules.filter((s) => s.dayOfWeek === day.dayIndex) as schedule}
+                          <ScheduleItem
+                            {schedule}
+                            dayOfWeek={day.dayIndex}
+                            isSelected={selectedEntries.some(
+                              (e) =>
+                                e.scheduleId === schedule.id &&
+                                e.dayOfWeek === day.dayIndex,
+                            )}
+                            isClickable={(!hasEntriesForWeek || weekEditMode) &&
+                              !processing}
+                            on:toggle={() =>
+                              toggleSelection(schedule.id, day.dayIndex)}
+                          />
+                        {/each}
+                      </div>
+                    </td>
+                  {/each}
+                </tr>
+              </tbody>
+            </table>
+          </div>
+
+          <div class="lg:hidden space-y-4">
+            {#each weekDates as day}
+              <div
+                class="collapse collapse-arrow bg-base-100 shadow-md border border-base-200"
+              >
+                <input type="checkbox" />
+                <div
+                  class="collapse-title text-lg font-medium flex justify-between items-center"
+                >
+                  <span>{day.name}</span>
+                  <span class="text-sm opacity-50 font-mono">{day.date}</span>
+                </div>
+                <div class="collapse-content">
+                  <div class="pt-2 space-y-2">
+                    {#each schedules.filter((s) => s.dayOfWeek === day.dayIndex) as schedule}
+                      <ScheduleItem
+                        {schedule}
+                        dayOfWeek={day.dayIndex}
+                        isSelected={selectedEntries.some(
+                          (e) =>
+                            e.scheduleId === schedule.id &&
+                            e.dayOfWeek === day.dayIndex,
+                        )}
+                        isClickable={(!hasEntriesForWeek || weekEditMode) &&
+                          !processing}
+                        on:toggle={() =>
+                          toggleSelection(schedule.id, day.dayIndex)}
+                      />
+                    {/each}
+                  </div>
+                </div>
               </div>
             {/each}
           </div>
+        {/if}
+      {:else if activeView === "market"}
+        <div class="flex justify-between items-center mb-4">
+          <h2 class="text-2xl font-bold">Offene Vertretungen</h2>
+          <button class="btn btn-ghost btn-sm" on:click={loadData}
+            ><i class="fas fa-sync"></i> Refresh</button
+          >
         </div>
-        <div class="lg:hidden space-y-4">
+
-          {#each Array(5) as _}
+        {#if openSubstitutions.length === 0}
-            <div class="skeleton h-16 w-full rounded-lg"></div>
+          <div class="hero bg-base-100 rounded-xl border border-base-200 py-12">
-          {/each}
+            <div class="hero-content text-center">
-        </div>
+              <div class="max-w-md">
-      {:else}
+                <h1 class="text-xl font-bold opacity-50">Alles ruhig</h1>
-        {#if hasEntriesForWeek && !weekEditMode}
+                <p class="py-6 opacity-70">
-          <div role="alert" class="alert alert-success shadow-sm">
+                  Aktuell werden keine Vertretungen gesucht.
-            <svg
+                </p>
-              xmlns="http://www.w3.org/2000/svg"
+              </div>
-              class="stroke-current shrink-0 h-6 w-6"
-              fill="none"
-              viewBox="0 0 24 24"
-              ><path
-                stroke-linecap="round"
-                stroke-linejoin="round"
-                stroke-width="2"
-                d="M9 12l2 2 4-4m6 2a9 9 0 11-18 0 9 9 0 0118 0z"
-              /></svg
-            >
-            <div>
-              <h3 class="font-bold">Erfasst!</h3>
-              <div class="text-xs">Stunden gespeichert.</div>
-            </div>
-            <button
-              class="btn btn-sm btn-outline"
-              on:click={() => (weekEditMode = true)}
-              disabled={processing}>Bearbeiten</button
-            >
-          </div>
-        {:else if weekEditMode}
-          <div role="alert" class="alert alert-warning shadow-sm">
-            <svg
-              xmlns="http://www.w3.org/2000/svg"
-              class="stroke-current shrink-0 h-6 w-6"
-              fill="none"
-              viewBox="0 0 24 24"
-              ><path
-                stroke-linecap="round"
-                stroke-linejoin="round"
-                stroke-width="2"
-                d="M12 9v2m0 4h.01m-6.938 4h13.856c1.54 0 2.502-1.667 1.732-3L13.732 4c-.77-1.333-2.694-1.333-3.464 0L3.34 16c-.77 1.333.192 3 1.732 3z"
-              /></svg
-            >
-            <div>
-              <h3 class="font-bold">Bearbeitungsmodus</h3>
-              <div class="text-xs">Speichern nicht vergessen!</div>
-            </div>
-            <div class="flex gap-2">
-              <button
-                class="btn btn-sm btn-error"
-                on:click={handleDeleteWeek}
-                disabled={processing}>Löschen</button
-              >
-              <button
-                class="btn btn-sm btn-ghost"
-                on:click={() => (weekEditMode = false)}>Abbrechen</button
-              >
             </div>
           </div>
         {:else}
-          <div role="alert" class="alert alert-info shadow-sm">
+          <div class="grid grid-cols-1 md:grid-cols-2 xl:grid-cols-3 gap-6">
-            <svg
+            {#each openSubstitutions as sub}
-              xmlns="http://www.w3.org/2000/svg"
-              fill="none"
-              viewBox="0 0 24 24"
-              class="stroke-current shrink-0 w-6 h-6"
-              ><path
-                stroke-linecap="round"
-                stroke-linejoin="round"
-                stroke-width="2"
-                d="M13 16h-1v-4h-1m1-4h.01M21 12a9 9 0 11-18 0 9 9 0 0118 0z"
-              ></path></svg
-            >
-            <div>
-              <h3 class="font-bold">Zeiterfassung</h3>
-              <div class="text-xs">Wählen Sie Ihre Stunden.</div>
-            </div>
-          </div>
-        {/if}
-
-        <div
-          class="overflow-x-auto hidden lg:block bg-base-100 rounded-2xl shadow-xl border border-base-200"
-        >
-          <table class="table table-fixed w-full">
-            <thead>
-              <tr>
-                {#each weekDates as day}
-                  <th class="text-center bg-base-200/50 py-4">
-                    <div class="font-bold text-lg">{day.name}</div>
-                    <div class="text-xs font-normal opacity-50">{day.date}</div>
-                  </th>
-                {/each}
-              </tr>
-            </thead>
-            <tbody>
-              <tr>
-                {#each weekDates as day}
-                  <td
-                    class="align-top p-2 min-w-[160px] border-r border-base-200 last:border-0"
-                  >
-                    <div class="space-y-2">
-                      {#each schedules.filter((s) => s.dayOfWeek === day.dayIndex) as schedule}
-                        <ScheduleItem
-                          {schedule}
-                          dayOfWeek={day.dayIndex}
-                          isSelected={selectedEntries.some(
-                            (e) =>
-                              e.scheduleId === schedule.id &&
-                              e.dayOfWeek === day.dayIndex,
-                          )}
-                          isClickable={(!hasEntriesForWeek || weekEditMode) &&
-                            !processing}
-                          on:toggle={() =>
-                            toggleSelection(schedule.id, day.dayIndex)}
-                        />
-                      {/each}
-                    </div>
-                  </td>
-                {/each}
-              </tr>
-            </tbody>
-          </table>
-        </div>
-
-        <div class="lg:hidden space-y-4">
-          {#each weekDates as day}
-            <div
-              class="collapse collapse-arrow bg-base-100 shadow-md border border-base-200"
-            >
-              <input type="checkbox" />
               <div
-                class="collapse-title text-lg font-medium flex justify-between items-center"
+                class="card bg-base-100 shadow-xl border border-base-200 hover:border-primary transition-all"
               >
-                <span>{day.name}</span>
+                <div class="card-body">
-                <span class="text-sm opacity-50 font-mono">{day.date}</span>
+                  <div class="flex justify-between items-start">
-              </div>
+                    <h3 class="card-title text-primary">{sub.title}</h3>
-              <div class="collapse-content">
+                    <div class="badge badge-outline font-mono">{sub.date}</div>
-                <div class="pt-2 space-y-2">
+                  </div>
-                  {#each schedules.filter((s) => s.dayOfWeek === day.dayIndex) as schedule}
+
-                    <ScheduleItem
+                  <p class="text-2xl font-bold my-2">
-                      {schedule}
+                    {sub.start_time}
-                      dayOfWeek={day.dayIndex}
+                    <span class="text-base font-normal opacity-50"
-                      isSelected={selectedEntries.some(
+                      >- {sub.end_time}</span
-                        (e) =>
+                    >
-                          e.scheduleId === schedule.id &&
+                  </p>
-                          e.dayOfWeek === day.dayIndex,
+
-                      )}
+                  {#if sub.notes}
-                      isClickable={(!hasEntriesForWeek || weekEditMode) &&
+                    <div
-                        !processing}
+                      class="alert alert-ghost text-sm py-2 px-3 my-2 bg-base-200/50"
-                      on:toggle={() =>
+                    >
-                        toggleSelection(schedule.id, day.dayIndex)}
+                      <svg
-                    />
+                        xmlns="http://www.w3.org/2000/svg"
-                  {/each}
+                        fill="none"
+                        viewBox="0 0 24 24"
+                        class="stroke-info shrink-0 w-4 h-4"
+                        ><path
+                          stroke-linecap="round"
+                          stroke-linejoin="round"
+                          stroke-width="2"
+                          d="M13 16h-1v-4h-1m1-4h.01M21 12a9 9 0 11-18 0 9 9 0 0118 0z"
+                        ></path></svg
+                      >
+                      <span>{sub.notes}</span>
+                    </div>
+                  {/if}
+
+                  <div class="card-actions justify-end mt-4 items-center">
+                    <button
+                      class="btn btn-sm btn-ghost text-xs"
+                      on:click={() => jumpToWeekOfDate(sub.date)}
+                    >
+                      Im Plan prüfen
+                    </button>
+                    <button
+                      class="btn btn-primary btn-sm"
+                      on:click={() => handleAcceptSub(sub)}
+                    >
+                      Übernehmen
+                    </button>
+                  </div>
                 </div>
               </div>
-            </div>
+            {/each}
-          {/each}
+          </div>
-        </div>
+        {/if}
       {/if}
     </div>
 
-    {#if (!hasEntriesForWeek || weekEditMode) && !isLoadingData}
+    {#if activeView === "schedule" && (!hasEntriesForWeek || weekEditMode) && !isLoadingData}
       <div
         class="sticky bottom-6 z-20 px-4 md:px-8 lg:px-10 pointer-events-none"
       >
@@ -561,6 +690,7 @@
           User Dashboard
         </div>
       </div>
+
       <ul class="menu p-4 w-full gap-2 text-base font-medium">
         <li
           class="menu-title opacity-50 uppercase text-xs font-bold tracking-wider mt-2 mb-1"
@@ -568,10 +698,14 @@
           Navigation
         </li>
         <li>
-          <a
+          <button
-            class="active bg-primary/10 text-primary"
+            class={activeView === "schedule"
-            href="#"
+              ? "active bg-primary/10 text-primary"
-            on:click={() => closeDrawer()}
+              : ""}
+            on:click={() => {
+              activeView = "schedule";
+              closeDrawer();
+            }}
           >
             <svg
               xmlns="http://www.w3.org/2000/svg"
@@ -587,7 +721,38 @@
               /></svg
             >
             Stundenplan
-          </a>
+          </button>
+        </li>
+        <li>
+          <button
+            class={activeView === "market"
+              ? "active bg-primary/10 text-primary"
+              : ""}
+            on:click={() => {
+              activeView = "market";
+              closeDrawer();
+            }}
+          >
+            <svg
+              xmlns="http://www.w3.org/2000/svg"
+              fill="none"
+              viewBox="0 0 24 24"
+              stroke-width="1.5"
+              stroke="currentColor"
+              class="w-5 h-5"
+              ><path
+                stroke-linecap="round"
+                stroke-linejoin="round"
+                d="M10.05 4.575a1.575 1.575 0 10-3.15 0v3m3.15-3v-1.5a1.575 1.575 0 013.15 0v1.5m-3.15 0l.075 5.925m3.075.75V4.575m0 0a1.575 1.575 0 013.15 0V15M6.9 7.575V12.75M5.25 21h13.5c1.125 0 2.025-.9 2.025-2.025v-9.75c0-1.125-.9-2.025-2.025-2.025H5.25A2.25 2.25 0 003 9.375v9.75c0 1.125.9 2.025 2.025 2.025z"
+              /></svg
+            >
+            Vertretungsbörse
+            {#if openSubstitutions.length > 0}
+              <span class="badge badge-sm badge-secondary ml-auto"
+                >{openSubstitutions.length}</span
+              >
+            {/if}
+          </button>
         </li>
         <li>
           <button on:click={() => (showPwModal = true)}>

frontend/src/components/admin/AdminSettingsTab.svelte

@@ -1,10 +1,34 @@
 <script>
-    import { uploadLogo } from "../../lib/api";
+    import { uploadLogo, getLicenseStatus, uploadLicense } from "../../lib/api";
     import { addToast } from "../../lib/stores";
+    import { onMount } from "svelte";
 
     let fileInput;
     let previewSrc = "/api/logo?t=" + Date.now();
     let uploading = false;
+    let licenseStatus = null;
+    let licFile;
+
+    onMount(async () => {
+        loadLicense();
+    });
+
+    async function loadLicense() {
+        try {
+            licenseStatus = await getLicenseStatus();
+        } catch (e) {}
+    }
+
+    async function handleLicenseUpload() {
+        if (!licFile.files[0]) return;
+        try {
+            await uploadLicense(licFile.files[0]);
+            addToast("Lizenzdatei hochgeladen", "success");
+            loadLicense();
+        } catch (e) {
+            addToast(e.message, "error");
+        }
+    }
 
     async function handleFileChange(e) {
         const file = e.target.files[0];
@@ -74,3 +98,57 @@
         </div>
     </div>
 </div>
+<div class="card bg-base-100 shadow-xl border border-base-200 max-w-2xl mt-8">
+    <div class="card-body">
+        <h3 class="card-title text-lg mb-4">Lizenzierung</h3>
+
+        {#if licenseStatus}
+            <div
+                class="stats stats-vertical lg:stats-horizontal shadow mb-4 border border-base-200"
+            >
+                <div class="stat">
+                    <div class="stat-title">Status</div>
+                    <div
+                        class="stat-value text-lg {licenseStatus.is_valid
+                            ? 'text-success'
+                            : 'text-error'}"
+                    >
+                        {licenseStatus.is_valid ? "Aktiv" : "Ungültig"}
+                    </div>
+                    <div class="stat-desc">{licenseStatus.message}</div>
+                </div>
+                <div class="stat">
+                    <div class="stat-title">Schule</div>
+                    <div class="stat-value text-lg">
+                        {licenseStatus.school_name || "-"}
+                    </div>
+                </div>
+                <div class="stat">
+                    <div class="stat-title">Gültig bis</div>
+                    <div class="stat-value text-lg">
+                        {licenseStatus.expires_at || "-"}
+                    </div>
+                </div>
+            </div>
+        {/if}
+
+        <div class="form-control w-full">
+            <label class="label">
+                <span class="label-text font-bold"
+                    >Lizenzdatei einspielen (.lic)</span
+                >
+            </label>
+            <div class="flex gap-4">
+                <input
+                    type="file"
+                    accept=".lic"
+                    class="file-input file-input-bordered w-full"
+                    bind:this={licFile}
+                />
+                <button class="btn btn-primary" on:click={handleLicenseUpload}
+                    >Hochladen</button
+                >
+            </div>
+        </div>
+    </div>
+</div>

frontend/src/components/admin/AdminSubstitutionsTab.svelte

@@ -0,0 +1,144 @@
+<script>
+  import { onMount } from "svelte";
+  import { getAllSubstitutions, createSubstitution } from "../../lib/api";
+  import { addToast, loading } from "../../lib/stores";
+
+  let substitutions = [];
+  let newSub = { date: "", startTime: "", endTime: "", title: "", notes: "" };
+
+  onMount(loadData);
+
+  async function loadData() {
+    try {
+      substitutions = await getAllSubstitutions();
+    } catch (e) {}
+  }
+
+  async function handleCreate() {
+    if (!newSub.date || !newSub.startTime || !newSub.title) {
+      addToast("Bitte Pflichtfelder ausfüllen", "warning");
+      return;
+    }
+    try {
+      await createSubstitution(newSub);
+      addToast("Vertretung ausgeschrieben", "success");
+      newSub = { date: "", startTime: "", endTime: "", title: "", notes: "" };
+      await loadData();
+    } catch (e) {
+      addToast(e.message, "error");
+    }
+  }
+</script>
+
+<div class="grid grid-cols-1 lg:grid-cols-3 gap-8">
+  <div class="card bg-base-100 shadow-xl border border-base-200 h-fit">
+    <div class="card-body">
+      <h3 class="card-title text-lg mb-4">Neue Vertretung ausschreiben</h3>
+
+      <div class="space-y-4">
+        <div class="form-control">
+          <label class="label">Titel / Klasse</label>
+          <input
+            type="text"
+            class="input input-bordered"
+            placeholder="z.B. Mathe 4a"
+            bind:value={newSub.title}
+          />
+        </div>
+
+        <div class="form-control">
+          <label class="label">Datum</label>
+          <input
+            type="date"
+            class="input input-bordered"
+            bind:value={newSub.date}
+          />
+        </div>
+
+        <div class="grid grid-cols-2 gap-2">
+          <div class="form-control">
+            <label class="label">Von</label>
+            <input
+              type="time"
+              class="input input-bordered"
+              bind:value={newSub.startTime}
+            />
+          </div>
+          <div class="form-control">
+            <label class="label">Bis</label>
+            <input
+              type="time"
+              class="input input-bordered"
+              bind:value={newSub.endTime}
+            />
+          </div>
+        </div>
+
+        <div class="form-control">
+          <label class="label">Notizen (Optional)</label>
+          <textarea
+            class="textarea textarea-bordered"
+            placeholder="z.B. Arbeitsblätter im Fach..."
+            bind:value={newSub.notes}
+          ></textarea>
+        </div>
+
+        <button
+          class="btn btn-primary w-full mt-4"
+          on:click={handleCreate}
+          disabled={$loading}
+        >
+          Veröffentlichen
+        </button>
+      </div>
+    </div>
+  </div>
+
+  <div class="lg:col-span-2">
+    <h3 class="font-bold text-xl mb-4">Übersicht</h3>
+    <div
+      class="overflow-x-auto bg-base-100 rounded-lg shadow border border-base-200"
+    >
+      <table class="table w-full">
+        <thead>
+          <tr>
+            <th>Datum</th>
+            <th>Zeit</th>
+            <th>Titel</th>
+            <th>Status</th>
+          </tr>
+        </thead>
+        <tbody>
+          {#each substitutions as s}
+            <tr class="hover">
+              <td class="whitespace-nowrap font-mono text-sm">{s.date}</td>
+              <td>{s.start_time} - {s.end_time}</td>
+              <td>
+                <div class="font-bold">{s.title}</div>
+                {#if s.notes}<div class="text-xs opacity-60 truncate max-w-xs">
+                    {s.notes}
+                  </div>{/if}
+              </td>
+              <td>
+                {#if s.taken_by_user_id}
+                  <span class="badge badge-success gap-2"> Übernommen </span>
+                  <div class="text-xs mt-1 opacity-70">
+                    von {s.taken_by_username}
+                  </div>
+                {:else}
+                  <span class="badge badge-warning badge-outline">Offen</span>
+                {/if}
+              </td>
+            </tr>
+          {:else}
+            <tr
+              ><td colspan="4" class="text-center opacity-50 py-8"
+                >Keine Einträge</td
+              ></tr
+            >
+          {/each}
+        </tbody>
+      </table>
+    </div>
+  </div>
+</div>

frontend/src/lib/api.js

@@ -304,3 +304,36 @@ export const changeMyPassword = (oldPw, newPw) =>
     old_password: oldPw,
     new_password: newPw,
   });
+
+export const getLicenseStatus = async () => request("/admin/settings/license");
+
+export const uploadLicense = async (file) => {
+  const formData = new FormData();
+  formData.append("license", file);
+  const token = localStorage.getItem("token");
+  const res = await fetch("/api/admin/settings/license", {
+    method: "POST",
+    headers: { Authorization: `Bearer ${token}` },
+    body: formData,
+  });
+  if (!res.ok) throw new Error("Upload fehlgeschlagen");
+  return await res.json();
+};
+
+export const getAllSubstitutions = async () => {
+  const data = await request("/admin/substitutions");
+  return data;
+};
+
+export const createSubstitution = (sub) => {
+  return request("/admin/substitutions", "POST", sub);
+};
+
+export const getOpenSubstitutions = async () => {
+  const data = await request("/substitutions/open");
+  return data;
+};
+
+export const acceptSubstitution = (id) => {
+  return request(`/substitutions/${id}/accept`, "POST");
+};