From 97177673e2a4a279175be9bb2561bce76785eccb Mon Sep 17 00:00:00 2001
From: Namu <namulabre@gmail.com>
Date: Sun, 30 Nov 2025 23:07:32 +0100
Subject: [PATCH] Fix: prevent school subject deletion if they have homework

---
 .../Homework/HomeworkDeletion.razor           |  21 ++++++++++++++++++
 .../SchoolSubject/SchoolSubjectDeletion.razor |  15 ++++++++++++-
 .../Data/Entities/SchoolSubject.cs            |   1 +
 .../Services/SchoolSubjectService.cs          |   5 ++++-
 WorkManagementTool/work_management.db-shm     | Bin 32768 -> 32768 bytes
 WorkManagementTool/work_management.db-wal     | Bin 16512 -> 45352 bytes
 6 files changed, 40 insertions(+), 2 deletions(-)
 create mode 100644 WorkManagementTool/Components/Homework/HomeworkDeletion.razor

diff --git a/WorkManagementTool/Components/Homework/HomeworkDeletion.razor b/WorkManagementTool/Components/Homework/HomeworkDeletion.razor
new file mode 100644
index 0000000..40eec88
--- /dev/null
+++ b/WorkManagementTool/Components/Homework/HomeworkDeletion.razor
@@ -0,0 +1,21 @@
+@using Microsoft.AspNetCore.Authorization
+@attribute [Authorize]
+@using WorkManagementTool.Services
+@using WorkManagementTool.Data.Entities
+@inject HomeworkService HomeworkService
+
+<button class="btn btn-danger">-</button>
+
+@code {
+    [Parameter]
+    public int HomeworkId { get; set; }
+
+    [Parameter]
+    public EventCallback<int> OnDeleted { get; set; }
+
+    private async Task Delete(MouseEventArgs e)
+    {
+        await HomeworkService.DeleteHomeworkAsync(HomeworkId);
+        await OnDeleted.InvokeAsync(HomeworkId);
+    }
+}
diff --git a/WorkManagementTool/Components/SchoolSubject/SchoolSubjectDeletion.razor b/WorkManagementTool/Components/SchoolSubject/SchoolSubjectDeletion.razor
index 4307f2d..99f64b6 100644
--- a/WorkManagementTool/Components/SchoolSubject/SchoolSubjectDeletion.razor
+++ b/WorkManagementTool/Components/SchoolSubject/SchoolSubjectDeletion.razor
@@ -5,7 +5,10 @@
 @using WorkManagementTool.Services
 @inject SchoolSubjectService SchoolSubjectService
 
-<button type="button" class="btn btn-danger" @onclick="Delete">-</button>
+@if (!hasHomeworks)
+{
+    <button type="button" class="btn btn-danger" @onclick="Delete">-</button>
+}
 
 @code {
     [Parameter]
@@ -14,6 +17,16 @@
     [Parameter]
     public EventCallback<int> OnDeleted { get; set; }
 
+    private bool hasHomeworks;
+
+    protected override async Task OnInitializedAsync()
+    {
+        var schoolSubject = await SchoolSubjectService.GetSchoolSubjectByIdAsync(Id);
+
+        hasHomeworks = schoolSubject is not null
+            && schoolSubject.Homeworks?.Count > 0;
+    }
+
     private async Task Delete(MouseEventArgs e)
     {
         await SchoolSubjectService.DeleteSchoolSubjectAsync(Id);
diff --git a/WorkManagementTool/Data/Entities/SchoolSubject.cs b/WorkManagementTool/Data/Entities/SchoolSubject.cs
index 61766ed..2353464 100644
--- a/WorkManagementTool/Data/Entities/SchoolSubject.cs
+++ b/WorkManagementTool/Data/Entities/SchoolSubject.cs
@@ -13,5 +13,6 @@ namespace WorkManagementTool.Data.Entities
         public DateTime CreatedAt { get; set; } = DateTime.UtcNow;
         public bool Deleted { get; set; } = false;
         public ApplicationUser CreatedBy { get; set; } = null!;
+        public List<Homework>? Homeworks { get; set; }
     }
 }
diff --git a/WorkManagementTool/Services/SchoolSubjectService.cs b/WorkManagementTool/Services/SchoolSubjectService.cs
index e69f40e..7fa02b5 100644
--- a/WorkManagementTool/Services/SchoolSubjectService.cs
+++ b/WorkManagementTool/Services/SchoolSubjectService.cs
@@ -20,7 +20,10 @@ namespace WorkManagementTool.Services
 
         public async Task<SchoolSubject?> GetSchoolSubjectByIdAsync(int id)
         {
-            return await _context.SchoolSubjects.FindAsync(id);
+            return await _context.SchoolSubjects
+                .Include(i => i.Homeworks)
+                .Where(w => w.Id == id)
+                .FirstOrDefaultAsync();
         }
 
         public async Task AddSchoolSubjectAsync(SchoolSubject subject)
diff --git a/WorkManagementTool/work_management.db-shm b/WorkManagementTool/work_management.db-shm
index 96f633caa013dd5a1d0b781a6e5256a248718b9f..690ee14c1dfa6a5c9e7446b13da0b408e4768443 100644
GIT binary patch
delta 210
zcmZo@U}|V!s+V}A%K!t63=9I?K#md+zmie!ioDK|Y@=(ex#G;%Cw6X&)Ve2k`;e+0
zW;V#&|40BT&cwhyu~A%-9mwSXVmTm|2VxK(%-*<A(Pi@`7X<-kRtC<E3x6{)vTa;=
ZnUR^DfeXZA=3wC7xKN#O^P5-^B>>f7HrN0F

delta 161
zcmZo@U}|V!s+V}A%K!t63=9G+K#md+JO94EvgC6`mW{5l=87|4pS+MO$(@o`w~JKu
qFtb7C{zn2(aV7?qiH+hLx5&9nJRr0Al8b`C#sj}NHou7#Q33!P%{H9?

diff --git a/WorkManagementTool/work_management.db-wal b/WorkManagementTool/work_management.db-wal
index ee497b8f56788412ebfcc827e660f3a2ca4a3a14..010feb5406374519ded7da92eaa4183d50635c3f 100644
GIT binary patch
delta 882
zcmZo@WL)uxX+wj95(5JRI}kJ2=o)LTIP>+1xlQkG<&%xSc!6S!{5%Z&JR1X<`0E=B
z83jY-fq<jY)HjrYgM)#S!#Fj`I5pAIK-V<Q!a&!=G$~m(DaF7**TT%m)X3P>!qPa^
zs3bo((V;>wttiCb*U=$D&n*a3#4*qj2s|AfBNNj>ELX>r;POgmqkLoU3{PY25R3An
zdN-e-0zWU)U~f0mG}p?Y;8dTqq>5ZKCy!L4tbkxk!+<JR%M91Na%X>2=di3mTU%pK
zZ%?3|t^vj_u7S=j?ok0gA-=wDUS>`%ks*PB5k{8DW@agAsk#QqhNikENroo67AD3<
zx+#{4MusLyspbZzrobTJfP{?%BygCvcsG9da9ElP95^=^_-||sJi<RQfy+ysIh2!_
z@BnI*gBS@hah-!o_TuFNhao0@X5jw}F;P{YhgqHz9%w)<@<6Nvi=|b*U2C_*>ij0G
z4JC3p&V2h;IJ5RAuE^yaCXt(%lxCD-l9r@vVVP{MYhq}UqHB?4mZF=Sl4P8mYHVR<
nYHoyx325Z*xt9G$=P!F9;V?ysiY|4TSIHdLBQdn`qQoEopo{$B

delta 9
QcmZ4Sh^e8GaYKUx02Sy1{{R30