backend/WorkClub.Api/Endpoints/Shifts/ShiftEndpoints.cs

@@ -118,17 +118,17 @@ public static class ShiftEndpoints
         ShiftService shiftService,
         HttpContext httpContext)
     {
-        var userIdClaim = httpContext.User.FindFirst("sub")?.Value;
+        var externalUserId = httpContext.User.FindFirst("sub")?.Value;
-        if (string.IsNullOrEmpty(userIdClaim) || !Guid.TryParse(userIdClaim, out var memberId))
+        if (string.IsNullOrEmpty(externalUserId))
         {
             return TypedResults.UnprocessableEntity("Invalid user ID");
         }
 
-        var (success, error, isConflict) = await shiftService.SignUpForShiftAsync(id, memberId);
+        var (success, error, isConflict) = await shiftService.SignUpForShiftAsync(id, externalUserId);
 
         if (!success)
         {
-            if (error == "Shift not found")
+            if (error == "Shift not found" || error == "Member not found")
                 return TypedResults.NotFound();
 
             if (error == "Cannot sign up for past shifts")
@@ -146,17 +146,17 @@ public static class ShiftEndpoints
         ShiftService shiftService,
         HttpContext httpContext)
     {
-        var userIdClaim = httpContext.User.FindFirst("sub")?.Value;
+        var externalUserId = httpContext.User.FindFirst("sub")?.Value;
-        if (string.IsNullOrEmpty(userIdClaim) || !Guid.TryParse(userIdClaim, out var memberId))
+        if (string.IsNullOrEmpty(externalUserId))
         {
             return TypedResults.UnprocessableEntity("Invalid user ID");
         }
 
-        var (success, error) = await shiftService.CancelSignupAsync(id, memberId);
+        var (success, error) = await shiftService.CancelSignupAsync(id, externalUserId);
 
         if (!success)
         {
-            if (error == "Sign-up not found")
+            if (error == "Sign-up not found" || error == "Member not found")
                 return TypedResults.NotFound();
 
             return TypedResults.UnprocessableEntity(error!);

backend/WorkClub.Api/Services/ShiftService.cs

@@ -207,10 +207,18 @@ public class ShiftService
         return true;
     }
 
-    public async Task<(bool success, string? error, bool isConflict)> SignUpForShiftAsync(Guid shiftId, Guid memberId)
+    public async Task<(bool success, string? error, bool isConflict)> SignUpForShiftAsync(Guid shiftId, string externalUserId)
     {
         var tenantId = _tenantProvider.GetTenantId();
 
+        var member = await _context.Members
+            .FirstOrDefaultAsync(m => m.ExternalUserId == externalUserId && m.TenantId == tenantId);
+
+        if (member == null)
+            return (false, "Member not found", false);
+
+        var memberId = member.Id;
+
         var shift = await _context.Shifts.FindAsync(shiftId);
 
         if (shift == null)
@@ -265,10 +273,18 @@ public class ShiftService
         return (false, "Shift capacity changed during sign-up", true);
     }
 
-    public async Task<(bool success, string? error)> CancelSignupAsync(Guid shiftId, Guid memberId)
+    public async Task<(bool success, string? error)> CancelSignupAsync(Guid shiftId, string externalUserId)
     {
+        var tenantId = _tenantProvider.GetTenantId();
+
+        var member = await _context.Members
+            .FirstOrDefaultAsync(m => m.ExternalUserId == externalUserId && m.TenantId == tenantId);
+
+        if (member == null)
+            return (false, "Member not found");
+
         var signup = await _context.ShiftSignups
-            .FirstOrDefaultAsync(ss => ss.ShiftId == shiftId && ss.MemberId == memberId);
+            .FirstOrDefaultAsync(ss => ss.ShiftId == shiftId && ss.MemberId == member.Id);
 
         if (signup == null)
         {

backend/WorkClub.Tests.Integration/Shifts/ShiftCrudTests.cs

@@ -3,6 +3,7 @@ using System.Net.Http.Json;
 using Microsoft.EntityFrameworkCore;
 using Microsoft.Extensions.DependencyInjection;
 using WorkClub.Domain.Entities;
+using WorkClub.Domain.Enums;
 using WorkClub.Infrastructure.Data;
 using WorkClub.Tests.Integration.Infrastructure;
 using Xunit;
@@ -23,9 +24,60 @@ public class ShiftCrudTests : IntegrationTestBase
         // Clean up existing test data
         context.ShiftSignups.RemoveRange(context.ShiftSignups);
         context.Shifts.RemoveRange(context.Shifts);
+        context.Members.RemoveRange(context.Members);
+        context.Clubs.RemoveRange(context.Clubs);
         await context.SaveChangesAsync();
     }
 
+    private async Task<(Guid clubId, Guid memberId, string externalUserId)> SeedMemberAsync(
+        string tenantId,
+        string email,
+        string? externalUserId = null,
+        ClubRole role = ClubRole.Member)
+    {
+        externalUserId ??= Guid.NewGuid().ToString();
+        var clubId = Guid.NewGuid();
+        var memberId = Guid.NewGuid();
+        var now = DateTimeOffset.UtcNow;
+
+        using var scope = Factory.Services.CreateScope();
+        var context = scope.ServiceProvider.GetRequiredService<AppDbContext>();
+
+        var existingClub = await context.Clubs.FirstOrDefaultAsync(c => c.TenantId == tenantId);
+        if (existingClub != null)
+        {
+            clubId = existingClub.Id;
+        }
+        else
+        {
+            context.Clubs.Add(new Club
+            {
+                Id = clubId,
+                TenantId = tenantId,
+                Name = "Test Club",
+                SportType = SportType.Tennis,
+                CreatedAt = now,
+                UpdatedAt = now
+            });
+        }
+
+        context.Members.Add(new Member
+        {
+            Id = memberId,
+            TenantId = tenantId,
+            ExternalUserId = externalUserId,
+            DisplayName = email.Split('@')[0],
+            Email = email,
+            Role = role,
+            ClubId = clubId,
+            CreatedAt = now,
+            UpdatedAt = now
+        });
+
+        await context.SaveChangesAsync();
+        return (clubId, memberId, externalUserId);
+    }
+
     [Fact]
     public async Task CreateShift_AsManager_ReturnsCreated()
     {
@@ -343,8 +395,8 @@ public class ShiftCrudTests : IntegrationTestBase
     public async Task SignUpForShift_WithCapacity_ReturnsOk()
     {
         // Arrange
+        var (clubId, memberId, externalUserId) = await SeedMemberAsync("tenant1", "member@test.com");
         var shiftId = Guid.NewGuid();
-        var clubId = Guid.NewGuid();
         var createdBy = Guid.NewGuid();
         var now = DateTimeOffset.UtcNow;
 
@@ -370,7 +422,7 @@ public class ShiftCrudTests : IntegrationTestBase
         }
 
         SetTenant("tenant1");
-        AuthenticateAs("member@test.com", new Dictionary<string, string> { ["tenant1"] = "Member" });
+        AuthenticateAs("member@test.com", new Dictionary<string, string> { ["tenant1"] = "Member" }, externalUserId);
 
         // Act
         var response = await Client.PostAsync($"/api/shifts/{shiftId}/signup", null);
@@ -384,6 +436,7 @@ public class ShiftCrudTests : IntegrationTestBase
             var context = scope.ServiceProvider.GetRequiredService<AppDbContext>();
             var signups = await context.ShiftSignups.Where(ss => ss.ShiftId == shiftId).ToListAsync();
             Assert.Single(signups);
+            Assert.Equal(memberId, signups[0].MemberId);
         }
     }
 
@@ -391,11 +444,14 @@ public class ShiftCrudTests : IntegrationTestBase
     public async Task SignUpForShift_WhenFull_ReturnsConflict()
     {
         // Arrange
+        var (clubId, _, externalUserId) = await SeedMemberAsync("tenant1", "member@test.com");
         var shiftId = Guid.NewGuid();
-        var clubId = Guid.NewGuid();
         var createdBy = Guid.NewGuid();
         var now = DateTimeOffset.UtcNow;
 
+        // Seed a different member to fill the single slot
+        var (_, fillerMemberId, _) = await SeedMemberAsync("tenant1", "filler@test.com");
+
         using (var scope = Factory.Services.CreateScope())
         {
             var context = scope.ServiceProvider.GetRequiredService<AppDbContext>();
@@ -420,7 +476,7 @@ public class ShiftCrudTests : IntegrationTestBase
                 Id = Guid.NewGuid(),
                 TenantId = "tenant1",
                 ShiftId = shiftId,
-                MemberId = Guid.NewGuid(),
+                MemberId = fillerMemberId,
                 SignedUpAt = now
             });
 
@@ -428,7 +484,7 @@ public class ShiftCrudTests : IntegrationTestBase
         }
 
         SetTenant("tenant1");
-        AuthenticateAs("member@test.com", new Dictionary<string, string> { ["tenant1"] = "Member" });
+        AuthenticateAs("member@test.com", new Dictionary<string, string> { ["tenant1"] = "Member" }, externalUserId);
 
         // Act
         var response = await Client.PostAsync($"/api/shifts/{shiftId}/signup", null);
@@ -441,8 +497,8 @@ public class ShiftCrudTests : IntegrationTestBase
     public async Task SignUpForShift_ForPastShift_ReturnsUnprocessableEntity()
     {
         // Arrange
+        var (clubId, _, externalUserId) = await SeedMemberAsync("tenant1", "member@test.com");
         var shiftId = Guid.NewGuid();
-        var clubId = Guid.NewGuid();
         var createdBy = Guid.NewGuid();
         var now = DateTimeOffset.UtcNow;
 
@@ -455,7 +511,7 @@ public class ShiftCrudTests : IntegrationTestBase
                 Id = shiftId,
                 TenantId = "tenant1",
                 Title = "Past Shift",
-                StartTime = now.AddHours(-2),  // Past shift
+                StartTime = now.AddHours(-2),
                 EndTime = now.AddHours(-1),
                 Capacity = 5,
                 ClubId = clubId,
@@ -468,7 +524,7 @@ public class ShiftCrudTests : IntegrationTestBase
         }
 
         SetTenant("tenant1");
-        AuthenticateAs("member@test.com", new Dictionary<string, string> { ["tenant1"] = "Member" });
+        AuthenticateAs("member@test.com", new Dictionary<string, string> { ["tenant1"] = "Member" }, externalUserId);
 
         // Act
         var response = await Client.PostAsync($"/api/shifts/{shiftId}/signup", null);
@@ -481,10 +537,9 @@ public class ShiftCrudTests : IntegrationTestBase
     public async Task SignUpForShift_Duplicate_ReturnsConflict()
     {
         // Arrange
+        var (clubId, memberId, externalUserId) = await SeedMemberAsync("tenant1", "member@test.com");
         var shiftId = Guid.NewGuid();
-        var clubId = Guid.NewGuid();
         var createdBy = Guid.NewGuid();
-        var memberId = Guid.Parse("00000000-0000-0000-0000-000000000001"); // Fixed member ID
         var now = DateTimeOffset.UtcNow;
 
         using (var scope = Factory.Services.CreateScope())
@@ -505,7 +560,6 @@ public class ShiftCrudTests : IntegrationTestBase
                 UpdatedAt = now
             });
 
-            // Add existing signup
             context.ShiftSignups.Add(new ShiftSignup
             {
                 Id = Guid.NewGuid(),
@@ -519,7 +573,7 @@ public class ShiftCrudTests : IntegrationTestBase
         }
 
         SetTenant("tenant1");
-        AuthenticateAs("member@test.com", new Dictionary<string, string> { ["tenant1"] = "Member" }, memberId.ToString());
+        AuthenticateAs("member@test.com", new Dictionary<string, string> { ["tenant1"] = "Member" }, externalUserId);
 
         // Act
         var response = await Client.PostAsync($"/api/shifts/{shiftId}/signup", null);
@@ -532,10 +586,9 @@ public class ShiftCrudTests : IntegrationTestBase
     public async Task CancelSignup_BeforeShift_ReturnsOk()
     {
         // Arrange
+        var (clubId, memberId, externalUserId) = await SeedMemberAsync("tenant1", "member@test.com");
         var shiftId = Guid.NewGuid();
-        var clubId = Guid.NewGuid();
         var createdBy = Guid.NewGuid();
-        var memberId = Guid.Parse("00000000-0000-0000-0000-000000000001");
         var now = DateTimeOffset.UtcNow;
 
         using (var scope = Factory.Services.CreateScope())
@@ -569,7 +622,7 @@ public class ShiftCrudTests : IntegrationTestBase
         }
 
         SetTenant("tenant1");
-        AuthenticateAs("member@test.com", new Dictionary<string, string> { ["tenant1"] = "Member" }, memberId.ToString());
+        AuthenticateAs("member@test.com", new Dictionary<string, string> { ["tenant1"] = "Member" }, externalUserId);
 
         // Act
         var response = await Client.DeleteAsync($"/api/shifts/{shiftId}/signup");
@@ -577,7 +630,6 @@ public class ShiftCrudTests : IntegrationTestBase
         // Assert
         Assert.Equal(HttpStatusCode.OK, response.StatusCode);
 
-        // Verify signup was deleted
         using (var scope = Factory.Services.CreateScope())
         {
             var context = scope.ServiceProvider.GetRequiredService<AppDbContext>();
@@ -590,8 +642,11 @@ public class ShiftCrudTests : IntegrationTestBase
     public async Task SignUpForShift_ConcurrentLastSlot_HandlesRaceCondition()
     {
         // Arrange
+        var (clubId, fillerMemberId, _) = await SeedMemberAsync("tenant1", "filler@test.com");
+        var (_, _, externalUserId1) = await SeedMemberAsync("tenant1", "member1@test.com");
+        var (_, _, externalUserId2) = await SeedMemberAsync("tenant1", "member2@test.com");
+
         var shiftId = Guid.NewGuid();
-        var clubId = Guid.NewGuid();
         var createdBy = Guid.NewGuid();
         var now = DateTimeOffset.UtcNow;
 
@@ -613,13 +668,12 @@ public class ShiftCrudTests : IntegrationTestBase
                 UpdatedAt = now
             });
 
-            // Add one signup (leaving one slot)
             context.ShiftSignups.Add(new ShiftSignup
             {
                 Id = Guid.NewGuid(),
                 TenantId = "tenant1",
                 ShiftId = shiftId,
-                MemberId = Guid.NewGuid(),
+                MemberId = fillerMemberId,
                 SignedUpAt = now
             });
 
@@ -628,24 +682,20 @@ public class ShiftCrudTests : IntegrationTestBase
 
         SetTenant("tenant1");
 
-        // Act - Simulate two concurrent requests
+        // Act
-        var member1 = Guid.NewGuid();
+        AuthenticateAs("member1@test.com", new Dictionary<string, string> { ["tenant1"] = "Member" }, externalUserId1);
-        var member2 = Guid.NewGuid();
-
-        AuthenticateAs("member1@test.com", new Dictionary<string, string> { ["tenant1"] = "Member" }, member1.ToString());
         var response1Task = Client.PostAsync($"/api/shifts/{shiftId}/signup", null);
 
-        AuthenticateAs("member2@test.com", new Dictionary<string, string> { ["tenant1"] = "Member" }, member2.ToString());
+        AuthenticateAs("member2@test.com", new Dictionary<string, string> { ["tenant1"] = "Member" }, externalUserId2);
         var response2Task = Client.PostAsync($"/api/shifts/{shiftId}/signup", null);
 
         var responses = await Task.WhenAll(response1Task, response2Task);
 
-        // Assert - One should succeed (200), one should fail (409)
+        // Assert
         var statuses = responses.Select(r => r.StatusCode).OrderBy(s => s).ToList();
         Assert.Contains(HttpStatusCode.OK, statuses);
         Assert.Contains(HttpStatusCode.Conflict, statuses);
 
-        // Verify only 2 total signups exist (capacity limit enforced)
         using (var scope = Factory.Services.CreateScope())
         {
             var context = scope.ServiceProvider.GetRequiredService<AppDbContext>();