create and assign expenses:

Datenfluss bei Gutter:
  Spieler wirft Gosse
    → RecordThrowAction (IsGutter=true)
    → HandleRecordThrow
    → FireThrowTriggersAsync
      → GameEventService.RegisterGutterAsync
        → TriggerService.FireTriggerAsync
          → PersonExpense in DB gespeichert ✓
          → PersonExpenseDto zurückgegeben
      → dispatcher.Dispatch(TriggerExpensesCreatedAction)
        → DayReducer fügt Expenses zu SelectedDayExpenses hinzu
          → UI aktualisiert sich automatisch ✓

src/Koogle.Application/DependencyInjection.cs

@@ -35,6 +35,7 @@ namespace Koogle.Application
             services.AddScoped<IDashboardService, DashboardService>();
             services.AddScoped<IEmailService, StubEmailService>();
             services.AddScoped<ITriggerService, TriggerService>();
+            services.AddScoped<IGameEventService, GameEventService>();
             services.AddScoped<IGamePersistenceService, GamePersistenceService>();
 
             // Note: Game types are registered in Koogle.Web where Blazor components are defined

src/Koogle.Application/Interfaces/IGameEventService.cs

@@ -0,0 +1,108 @@
+using Koogle.Application.DTOs;
+
+namespace Koogle.Application.Interfaces;
+
+/// <summary>
+/// Service for handling game events that may trigger automatic expense assignments.
+/// Supports inverse expenses (charged to all other participants).
+/// </summary>
+public interface IGameEventService
+{
+    /// <summary>
+    /// Registers a gutter throw (left or right) and fires associated triggers.
+    /// </summary>
+    /// <param name="personId">The player who threw the gutter.</param>
+    /// <param name="dayId">The current day.</param>
+    /// <param name="gameId">The current game.</param>
+    /// <param name="allParticipantIds">All participant IDs (required for inverse expenses).</param>
+    /// <param name="isFirstThrow">True if this is the first throw (Anwurf).</param>
+    /// <param name="ct">Cancellation token.</param>
+    /// <returns>List of assigned expenses.</returns>
+    Task<List<PersonExpenseDto>> RegisterGutterAsync(
+        Guid personId,
+        Guid dayId,
+        Guid gameId,
+        IReadOnlyList<Guid> allParticipantIds,
+        bool isFirstThrow = false,
+        CancellationToken ct = default);
+
+    /// <summary>
+    /// Registers a strike (alle Neune) and fires associated triggers.
+    /// </summary>
+    Task<List<PersonExpenseDto>> RegisterStrikeAsync(
+        Guid personId,
+        Guid dayId,
+        Guid gameId,
+        IReadOnlyList<Guid> allParticipantIds,
+        CancellationToken ct = default);
+
+    /// <summary>
+    /// Registers a bell hit (Klingel) and fires associated triggers.
+    /// </summary>
+    Task<List<PersonExpenseDto>> RegisterBellAsync(
+        Guid personId,
+        Guid dayId,
+        Guid gameId,
+        IReadOnlyList<Guid> allParticipantIds,
+        CancellationToken ct = default);
+
+    /// <summary>
+    /// Registers a circle (Kranz) and fires associated triggers.
+    /// </summary>
+    Task<List<PersonExpenseDto>> RegisterCircleAsync(
+        Guid personId,
+        Guid dayId,
+        Guid gameId,
+        IReadOnlyList<Guid> allParticipantIds,
+        CancellationToken ct = default);
+
+    /// <summary>
+    /// Registers a no-wood throw (kein Holz) and fires associated triggers.
+    /// </summary>
+    Task<List<PersonExpenseDto>> RegisterNoWoodAsync(
+        Guid personId,
+        Guid dayId,
+        Guid gameId,
+        IReadOnlyList<Guid> allParticipantIds,
+        CancellationToken ct = default);
+
+    /// <summary>
+    /// Registers player elimination and fires associated triggers.
+    /// </summary>
+    Task<List<PersonExpenseDto>> RegisterEliminatedAsync(
+        Guid personId,
+        Guid dayId,
+        Guid gameId,
+        IReadOnlyList<Guid> allParticipantIds,
+        CancellationToken ct = default);
+
+    /// <summary>
+    /// Registers expense points (e.g., Scheißspiel points) with multiplier.
+    /// </summary>
+    /// <param name="personId">The player receiving points.</param>
+    /// <param name="dayId">The current day.</param>
+    /// <param name="gameId">The current game.</param>
+    /// <param name="allParticipantIds">All participant IDs (required for inverse expenses).</param>
+    /// <param name="points">Number of expense points (multiplier).</param>
+    /// <param name="ct">Cancellation token.</param>
+    Task<List<PersonExpenseDto>> RegisterExpensePointsAsync(
+        Guid personId,
+        Guid dayId,
+        Guid gameId,
+        IReadOnlyList<Guid> allParticipantIds,
+        int points,
+        CancellationToken ct = default);
+
+    /// <summary>
+    /// Registers player absence on match day.
+    /// </summary>
+    /// <param name="personId">The absent player.</param>
+    /// <param name="dayId">The current day.</param>
+    /// <param name="allParticipantIds">All participant IDs (required for inverse expenses).</param>
+    /// <param name="ct">Cancellation token.</param>
+    Task<List<PersonExpenseDto>> RegisterAbsentAsync(
+        Guid personId,
+        Guid dayId,
+        IReadOnlyList<Guid> allParticipantIds,
+        CancellationToken ct = default);
+}

src/Koogle.Application/Interfaces/ITriggerService.cs

@@ -33,19 +33,22 @@ public interface ITriggerService
 
     /// <summary>
     /// Fires a trigger, creating PersonExpenses for all linked expenses.
+    /// For inverse expenses, charges all participants except the triggering person.
     /// </summary>
     /// <param name="type">The trigger type (e.g., ExpensePoint, Circle, Strike).</param>
-    /// <param name="personId">The person receiving the expense(s).</param>
+    /// <param name="triggeringPersonId">The person who triggered the event.</param>
     /// <param name="dayId">The day context for the expense.</param>
     /// <param name="gameId">Optional game context for the expense.</param>
+    /// <param name="allParticipantIds">All participant IDs (required for inverse expenses).</param>
     /// <param name="multiplier">Multiplier for expense price (e.g., remaining points in Scheiss-Spiel). Default is 1.</param>
     /// <param name="ct">Cancellation token.</param>
     /// <returns>A list of created PersonExpense DTOs.</returns>
     Task<List<PersonExpenseDto>> FireTriggerAsync(
         ExpenseTriggerType type,
-        Guid personId,
+        Guid triggeringPersonId,
         Guid dayId,
         Guid? gameId = null,
+        IReadOnlyList<Guid>? allParticipantIds = null,
         int multiplier = 1,
         CancellationToken ct = default);
 

src/Koogle.Application/Services/GameEventService.cs

@@ -0,0 +1,184 @@
+using Koogle.Application.DTOs;
+using Koogle.Application.Interfaces;
+using Koogle.Domain.Enums;
+
+namespace Koogle.Application.Services;
+
+/// <summary>
+/// Handles game events and fires associated expense triggers.
+/// Supports inverse expenses (charged to all other participants).
+/// Example: A strike with inverse expense charges all OTHER players.
+/// </summary>
+public class GameEventService : IGameEventService
+{
+    private readonly ITriggerService _triggerService;
+
+    public GameEventService(ITriggerService triggerService)
+    {
+        _triggerService = triggerService;
+    }
+
+    /// <inheritdoc />
+    public async Task<List<PersonExpenseDto>> RegisterGutterAsync(
+        Guid personId,
+        Guid dayId,
+        Guid gameId,
+        IReadOnlyList<Guid> allParticipantIds,
+        bool isFirstThrow = false,
+        CancellationToken ct = default)
+    {
+        var expenses = new List<PersonExpenseDto>();
+
+        // Fire standard Gutter trigger (left or right gutter)
+        var gutterExpenses = await _triggerService.FireTriggerAsync(
+            ExpenseTriggerType.Gutter,
+            personId,
+            dayId,
+            gameId,
+            allParticipantIds,
+            ct: ct);
+        expenses.AddRange(gutterExpenses);
+
+        // If gutter on first throw, also fire FullGutter trigger
+        if (isFirstThrow)
+        {
+            var fullGutterExpenses = await _triggerService.FireTriggerAsync(
+                ExpenseTriggerType.FullGutter,
+                personId,
+                dayId,
+                gameId,
+                allParticipantIds,
+                ct: ct);
+            expenses.AddRange(fullGutterExpenses);
+        }
+
+        return expenses;
+    }
+
+    /// <inheritdoc />
+    public async Task<List<PersonExpenseDto>> RegisterStrikeAsync(
+        Guid personId,
+        Guid dayId,
+        Guid gameId,
+        IReadOnlyList<Guid> allParticipantIds,
+        CancellationToken ct = default)
+    {
+        // Strike = "alle Neune" - if inverse, charges all other players
+        return await _triggerService.FireTriggerAsync(
+            ExpenseTriggerType.Strike,
+            personId,
+            dayId,
+            gameId,
+            allParticipantIds,
+            ct: ct);
+    }
+
+    /// <inheritdoc />
+    public async Task<List<PersonExpenseDto>> RegisterBellAsync(
+        Guid personId,
+        Guid dayId,
+        Guid gameId,
+        IReadOnlyList<Guid> allParticipantIds,
+        CancellationToken ct = default)
+    {
+        // Bell hit = "Klingel getroffen"
+        return await _triggerService.FireTriggerAsync(
+            ExpenseTriggerType.Bell,
+            personId,
+            dayId,
+            gameId,
+            allParticipantIds,
+            ct: ct);
+    }
+
+    /// <inheritdoc />
+    public async Task<List<PersonExpenseDto>> RegisterCircleAsync(
+        Guid personId,
+        Guid dayId,
+        Guid gameId,
+        IReadOnlyList<Guid> allParticipantIds,
+        CancellationToken ct = default)
+    {
+        // Circle = "Kranz" - specific pin arrangement
+        return await _triggerService.FireTriggerAsync(
+            ExpenseTriggerType.Circle,
+            personId,
+            dayId,
+            gameId,
+            allParticipantIds,
+            ct: ct);
+    }
+
+    /// <inheritdoc />
+    public async Task<List<PersonExpenseDto>> RegisterNoWoodAsync(
+        Guid personId,
+        Guid dayId,
+        Guid gameId,
+        IReadOnlyList<Guid> allParticipantIds,
+        CancellationToken ct = default)
+    {
+        // No wood = "Kein Holz" - no pins knocked down
+        return await _triggerService.FireTriggerAsync(
+            ExpenseTriggerType.NoWood,
+            personId,
+            dayId,
+            gameId,
+            allParticipantIds,
+            ct: ct);
+    }
+
+    /// <inheritdoc />
+    public async Task<List<PersonExpenseDto>> RegisterEliminatedAsync(
+        Guid personId,
+        Guid dayId,
+        Guid gameId,
+        IReadOnlyList<Guid> allParticipantIds,
+        CancellationToken ct = default)
+    {
+        // Player eliminated from game
+        return await _triggerService.FireTriggerAsync(
+            ExpenseTriggerType.Eliminated,
+            personId,
+            dayId,
+            gameId,
+            allParticipantIds,
+            ct: ct);
+    }
+
+    /// <inheritdoc />
+    public async Task<List<PersonExpenseDto>> RegisterExpensePointsAsync(
+        Guid personId,
+        Guid dayId,
+        Guid gameId,
+        IReadOnlyList<Guid> allParticipantIds,
+        int points,
+        CancellationToken ct = default)
+    {
+        // Expense points with multiplier (e.g., remaining points in Scheißspiel)
+        return await _triggerService.FireTriggerAsync(
+            ExpenseTriggerType.ExpensePoint,
+            personId,
+            dayId,
+            gameId,
+            allParticipantIds,
+            multiplier: points,
+            ct: ct);
+    }
+
+    /// <inheritdoc />
+    public async Task<List<PersonExpenseDto>> RegisterAbsentAsync(
+        Guid personId,
+        Guid dayId,
+        IReadOnlyList<Guid> allParticipantIds,
+        CancellationToken ct = default)
+    {
+        // Player absent on match day - no gameId needed
+        return await _triggerService.FireTriggerAsync(
+            ExpenseTriggerType.Absent,
+            personId,
+            dayId,
+            gameId: null,
+            allParticipantIds,
+            ct: ct);
+    }
+}

src/Koogle.Application/Services/TriggerService.cs

@@ -82,9 +82,10 @@ public class TriggerService : ITriggerService
     /// <inheritdoc />
     public async Task<List<PersonExpenseDto>> FireTriggerAsync(
         ExpenseTriggerType type,
-        Guid personId,
+        Guid triggeringPersonId,
         Guid dayId,
         Guid? gameId = null,
+        IReadOnlyList<Guid>? allParticipantIds = null,
         int multiplier = 1,
         CancellationToken ct = default)
     {
@@ -105,11 +106,11 @@ public class TriggerService : ITriggerService
         if (day.Status == DayStatus.Closed)
             throw new InvalidOperationException("Cannot add expenses to a closed day.");
 
-        // Validate person exists
-        var person = await context.Persons
-            .Where(p => p.Id == personId && p.ClubId == _clubContext.ClubId && !p.IsDeleted)
+        // Validate triggering person exists
+        var triggeringPerson = await context.Persons
+            .Where(p => p.Id == triggeringPersonId && p.ClubId == _clubContext.ClubId && !p.IsDeleted)
             .FirstOrDefaultAsync(ct)
-            ?? throw new InvalidOperationException($"Person with id {personId} not found.");
+            ?? throw new InvalidOperationException($"Person with id {triggeringPersonId} not found.");
 
         var createdExpenses = new List<PersonExpense>();
 
@@ -118,27 +119,51 @@ public class TriggerService : ITriggerService
             // Calculate price with multiplier
             var price = expense.Price * multiplier;
 
-            var personExpense = new PersonExpense
+            // Determine target persons based on IsInverse flag
+            IEnumerable<Guid> targetPersonIds;
+            if (expense.IsInverse)
             {
-                Id = Guid.NewGuid(),
-                PersonId = personId,
-                ExpenseId = expense.Id,
-                DayId = dayId,
-                GameId = gameId,
-                ClubId = _clubContext.ClubId,
-                Name = expense.Name,
-                Price = price,
-                ExpenseType = expense.ExpenseType,
-                PersonExpenseStatus = PersonExpenseStatus.Open,
-                AssignedById = Guid.Empty, // TODO: Get from ICurrentUserService when available
-                CreatedAt = DateTime.UtcNow,
-                IsDeleted = false
-            };
+                // Inverse: charge all participants EXCEPT the triggering person
+                if (allParticipantIds == null || allParticipantIds.Count == 0)
+                {
+                    // No participants provided - skip inverse expense
+                    continue;
+                }
+                targetPersonIds = allParticipantIds.Where(id => id != triggeringPersonId);
+            }
+            else
+            {
+                // Normal: charge only the triggering person
+                targetPersonIds = [triggeringPersonId];
+            }
 
-            context.PersonExpenses.Add(personExpense);
-            createdExpenses.Add(personExpense);
+            foreach (var targetPersonId in targetPersonIds)
+            {
+                var personExpense = new PersonExpense
+                {
+                    Id = Guid.NewGuid(),
+                    PersonId = targetPersonId,
+                    ExpenseId = expense.Id,
+                    DayId = dayId,
+                    GameId = gameId,
+                    ClubId = _clubContext.ClubId,
+                    Name = expense.Name,
+                    Price = price,
+                    ExpenseType = expense.ExpenseType,
+                    PersonExpenseStatus = PersonExpenseStatus.Open,
+                    AssignedById = Guid.Empty, // TODO: Get from ICurrentUserService when available
+                    CreatedAt = DateTime.UtcNow,
+                    IsDeleted = false
+                };
+
+                context.PersonExpenses.Add(personExpense);
+                createdExpenses.Add(personExpense);
+            }
         }
 
+        if (createdExpenses.Count == 0)
+            return [];
+
         await context.SaveChangesAsync(ct);
 
         // Reload with navigation properties

src/Koogle.Web/Store/DayState/DayActions.cs

@@ -261,3 +261,8 @@ public record UpdatePersonExpenseStatusSuccessAction(PersonExpenseDto Expense);
 /// Action dispatched when updating person expense status fails.
 /// </summary>
 public record UpdatePersonExpenseStatusFailureAction(string Error);
+
+/// <summary>
+/// Action dispatched when trigger-based expenses are created (e.g., Gutter, Strike).
+/// </summary>
+public record TriggerExpensesCreatedAction(IReadOnlyList<PersonExpenseDto> Expenses);

src/Koogle.Web/Store/DayState/DayReducers.cs

@@ -555,6 +555,16 @@ public static class DayReducers
             Error = action.Error
         };
 
+    /// <summary>
+    /// Handles TriggerExpensesCreatedAction - adds trigger-created expenses to list.
+    /// </summary>
+    [ReducerMethod]
+    public static DayState OnTriggerExpensesCreated(DayState state, TriggerExpensesCreatedAction action)
+        => state with
+        {
+            SelectedDayExpenses = [.. state.SelectedDayExpenses, .. action.Expenses]
+        };
+
     /// <summary>
     /// Handles DeletePersonExpenseAction - sets loading state.
     /// </summary>

src/Koogle.Web/Store/GameState/GameEffects.cs

@@ -7,6 +7,7 @@ using Koogle.Domain.Enums;
 using Koogle.Infrastructure.Configuration;
 using Koogle.Web.Hubs;
 using Koogle.Web.Services;
+using Koogle.Web.Store.DayState;
 using Microsoft.Extensions.Options;
 
 namespace Koogle.Web.Store.GameState;
@@ -24,6 +25,7 @@ public class GameEffects
     private readonly GameDefinitionRegistry _gameRegistry;
     private readonly GameHubService _hubService;
     private readonly IOptions<AppSettings> _appSettings;
+    private readonly IGameEventService _gameEventService;
 
     // Debounce timer for save operations
     private Timer? _saveDebounceTimer;
@@ -39,7 +41,8 @@ public class GameEffects
         ICurrentClubContext clubContext,
         GameDefinitionRegistry gameRegistry,
         GameHubService hubService,
-        IOptions<AppSettings> appSettings)
+        IOptions<AppSettings> appSettings,
+        IGameEventService gameEventService)
     {
         _logger = logger;
         _gameState = gameState;
@@ -48,6 +51,7 @@ public class GameEffects
         _gameRegistry = gameRegistry;
         _hubService = hubService;
         _appSettings = appSettings;
+        _gameEventService = gameEventService;
     }
 
     /// <summary>
@@ -295,9 +299,10 @@ public class GameEffects
 
     /// <summary>
     /// Handles RecordThrowAction - calls ProcessThrow and applies game logic.
+    /// Also fires expense triggers for special events (Gutter, Strike, etc.).
     /// </summary>
     [EffectMethod]
-    public Task HandleRecordThrow(RecordThrowAction action, IDispatcher dispatcher)
+    public async Task HandleRecordThrow(RecordThrowAction action, IDispatcher dispatcher)
     {
         var state = _gameState.Value;
         var gameTypeName = state.GameTypeName;
@@ -307,13 +312,13 @@ public class GameEffects
         if (state.IsGameOver)
         {
             _logger.LogWarning("Cannot process throw: game is already over");
-            return Task.CompletedTask;
+            return;
         }
 
         if (string.IsNullOrEmpty(gameTypeName) || !currentPlayerId.HasValue)
         {
             _logger.LogWarning("Cannot process throw: missing game type or player");
-            return Task.CompletedTask;
+            return;
         }
 
         // Get game logic service (may be null if game type not registered)
@@ -414,10 +419,13 @@ public class GameEffects
             isGameOver,
             winnerId));
 
+        // Fire expense triggers for special throw events
+        await FireThrowTriggersAsync(state, currentPlayerId.Value, action, afterThrowState, dispatcher);
+
         // If game is over, skip save (user must confirm end via UI)
         if (isGameOver)
         {
-            return Task.CompletedTask;
+            return;
         }
 
         // Debounce save operations to avoid excessive DB writes
@@ -427,8 +435,6 @@ public class GameEffects
             null,
             SaveDebounceMs,
             Timeout.Infinite);
-
-        return Task.CompletedTask;
     }
 
     /// <summary>
@@ -825,4 +831,141 @@ public class GameEffects
         CurrentPlayerIndex = dto.CurrentPlayerIndex,
         Mode = (ParticipantsMode)dto.Mode
     };
+
+    /// <summary>
+    /// Fires expense triggers based on throw events (Gutter, Strike, Circle, etc.).
+    /// Dispatches TriggerExpensesCreatedAction to update UI.
+    /// </summary>
+    private async Task FireThrowTriggersAsync(
+        GameState state,
+        Guid currentPlayerId,
+        RecordThrowAction action,
+        AfterThrowState afterThrowState,
+        IDispatcher dispatcher)
+    {
+        // Skip if no day or game context
+        if (!state.DayId.HasValue || !state.ActiveGameId.HasValue)
+        {
+            _logger.LogDebug("Skipping trigger fire: missing DayId or GameId");
+            return;
+        }
+
+        var dayId = state.DayId.Value;
+        var gameId = state.ActiveGameId.Value;
+        var allParticipantIds = state.Participants.PlayerIds.ToList();
+        var allCreatedExpenses = new List<PersonExpenseDto>();
+
+        try
+        {
+            // Check for Gutter
+            if (action.IsGutter)
+            {
+                // Check if this is the first throw of the round (Anwurf)
+                bool isFirstThrow = afterThrowState.ThrowPanel.ThrowCounterPerRound == 1;
+
+                var expenses = await _gameEventService.RegisterGutterAsync(
+                    currentPlayerId,
+                    dayId,
+                    gameId,
+                    allParticipantIds,
+                    isFirstThrow);
+
+                allCreatedExpenses.AddRange(expenses);
+
+                if (expenses.Count > 0)
+                {
+                    _logger.LogInformation(
+                        "Gutter trigger fired: {Count} expenses assigned to player {PlayerId}",
+                        expenses.Count, currentPlayerId);
+                }
+            }
+
+            // Check for Strike (alle Neune)
+            if (afterThrowState.IsStrike)
+            {
+                var expenses = await _gameEventService.RegisterStrikeAsync(
+                    currentPlayerId,
+                    dayId,
+                    gameId,
+                    allParticipantIds);
+
+                allCreatedExpenses.AddRange(expenses);
+
+                if (expenses.Count > 0)
+                {
+                    _logger.LogInformation(
+                        "Strike trigger fired: {Count} expenses assigned",
+                        expenses.Count);
+                }
+            }
+
+            // Check for Circle (Kranz)
+            if (afterThrowState.IsCircle)
+            {
+                var expenses = await _gameEventService.RegisterCircleAsync(
+                    currentPlayerId,
+                    dayId,
+                    gameId,
+                    allParticipantIds);
+
+                allCreatedExpenses.AddRange(expenses);
+
+                if (expenses.Count > 0)
+                {
+                    _logger.LogInformation(
+                        "Circle trigger fired: {Count} expenses assigned",
+                        expenses.Count);
+                }
+            }
+
+            // Check for No Wood (kein Holz) - 0 pins knocked but not a gutter
+            if (afterThrowState.PinsKnocked == 0 && !action.IsGutter)
+            {
+                var expenses = await _gameEventService.RegisterNoWoodAsync(
+                    currentPlayerId,
+                    dayId,
+                    gameId,
+                    allParticipantIds);
+
+                allCreatedExpenses.AddRange(expenses);
+
+                if (expenses.Count > 0)
+                {
+                    _logger.LogInformation(
+                        "NoWood trigger fired: {Count} expenses assigned",
+                        expenses.Count);
+                }
+            }
+
+            // Check for Bell hit
+            if (afterThrowState.ThrowPanel.BellValue)
+            {
+                var expenses = await _gameEventService.RegisterBellAsync(
+                    currentPlayerId,
+                    dayId,
+                    gameId,
+                    allParticipantIds);
+
+                allCreatedExpenses.AddRange(expenses);
+
+                if (expenses.Count > 0)
+                {
+                    _logger.LogInformation(
+                        "Bell trigger fired: {Count} expenses assigned",
+                        expenses.Count);
+                }
+            }
+
+            // Dispatch action to update UI with all created expenses
+            if (allCreatedExpenses.Count > 0)
+            {
+                dispatcher.Dispatch(new DayState.TriggerExpensesCreatedAction(allCreatedExpenses));
+            }
+        }
+        catch (Exception ex)
+        {
+            _logger.LogError(ex, "Error firing throw triggers for player {PlayerId}", currentPlayerId);
+            // Don't fail the throw recording if trigger fails
+        }
+    }
 }