Resolve N + 1 problem and add cascading deletion

Open Judge System/Data/OJS.Data/IOjsData.cs

@@ -12,7 +12,7 @@ public interface IOjsData : IDisposable
     {
         IContestsRepository Contests { get; }
 
-        IDeletableEntityRepository<Problem> Problems { get; }
+        IProblemsRepository Problems { get; }
 
         ITestRepository Tests { get; }
 

Open Judge System/Data/OJS.Data/OJS.Data.csproj

@@ -91,6 +91,7 @@
     <Compile Include="Repositories\Contracts\IContestsRepository.cs" />
     <Compile Include="IOjsData.cs" />
     <Compile Include="IOjsDbContext.cs" />
+    <Compile Include="Repositories\Contracts\IProblemsRepository.cs" />
     <Compile Include="Repositories\Contracts\ISubmissionsRepository.cs" />
     <Compile Include="Repositories\Contracts\ITestRepository.cs" />
     <Compile Include="Repositories\Contracts\ITestRunsRepository.cs" />
@@ -100,6 +101,7 @@
     <Compile Include="Properties\AssemblyInfo.cs" />
     <Compile Include="Repositories\Contracts\IParticipantsRepository.cs" />
     <Compile Include="Repositories\ParticipantsRepository.cs" />
+    <Compile Include="Repositories\ProblemsRepository.cs" />
     <Compile Include="Repositories\SubmissionsRepository.cs" />
     <Compile Include="Repositories\TestRepository.cs" />
     <Compile Include="Repositories\TestRunsRepository.cs" />

Open Judge System/Data/OJS.Data/OjsData.cs

@@ -29,7 +29,7 @@ public OjsData(IOjsDbContext context)
 
         public IContestsRepository Contests => (ContestsRepository)this.GetRepository<Contest>();
 
-        public IDeletableEntityRepository<Problem> Problems => this.GetDeletableEntityRepository<Problem>();
+        public IProblemsRepository Problems => (ProblemsRepository)this.GetRepository<Problem>();
 
         public ITestRepository Tests => (TestRepository)this.GetRepository<Test>();
 
@@ -111,6 +111,11 @@ private IRepository<T> GetRepository<T>()
                     type = typeof(ContestsRepository);
                 }
 
+                if (typeof(T).IsAssignableFrom(typeof(Problem)))
+                {
+                    type = typeof(ProblemsRepository);
+                }
+
                 if (typeof(T).IsAssignableFrom(typeof(Submission)))
                 {
                     type = typeof(SubmissionsRepository);

Open Judge System/Data/OJS.Data/Repositories/Contracts/IProblemsRepository.cs

@@ -0,0 +1,14 @@
+namespace OJS.Data.Repositories.Contracts
+{
+    using System;
+    using System.Linq;
+    using System.Linq.Expressions;
+
+    using OJS.Data.Contracts;
+    using OJS.Data.Models;
+
+    public interface IProblemsRepository : IRepository<Problem>, IDeletableEntityRepository<Problem>
+    {
+        IQueryable<Problem> AllIncludesSubmissionsTestsAndResources(Expression<Func<Problem, bool>> orExpressionProblemIds);
+    }
+}

Open Judge System/Data/OJS.Data/Repositories/ProblemsRepository.cs

@@ -0,0 +1,24 @@
+namespace OJS.Data.Repositories
+{
+    using System;
+    using System.Data.Entity;
+    using System.Linq;
+    using System.Linq.Expressions;
+
+    using OJS.Data.Models;
+    using OJS.Data.Repositories.Base;
+    using OJS.Data.Repositories.Contracts;
+
+    public class ProblemsRepository : DeletableEntityRepository<Problem>, IProblemsRepository
+    {
+        public ProblemsRepository(IOjsDbContext context)
+            : base(context)
+        {
+        }
+
+        public IQueryable<Problem> AllIncludesSubmissionsTestsAndResources(Expression<Func<Problem, bool>> orExpressionProblemIds)
+        {
+            return this.All().Where(orExpressionProblemIds).Include(p => p.Submissions).Include(p => p.Tests).Include(p => p.Resources);
+        }
+    }
+}

Open Judge System/Web/OJS.Web/Areas/Administration/Controllers/ProblemsController.cs

@@ -374,11 +374,32 @@ public ActionResult ConfirmDeleteAll(int? id)
                 return this.RedirectToAction(GlobalConstants.Index);
             }
 
+            var orExpressionProblemIds = ExpressionBuilder.BuildOrExpression<Problem, int>(contest.Problems.Select(p => p.Id), p => p.Id);
+
+            var problems = this.Data.Problems.AllIncludesSubmissionsTestsAndResources(orExpressionProblemIds);
+
             // TODO: check for N + 1
-            foreach (var problem in contest.Problems.ToList())
+            foreach (var problem in problems.ToList())
             {
-                // TODO: Add cascading deletion of submissions, tests, resources
                 this.Data.Problems.Delete(problem.Id);
+
+                var tests = problem.Tests;
+                foreach (var test in tests)
+                {
+                    this.Data.Tests.Delete(test.Id);
+                }
+
+                var submissions = problem.Submissions;
+                foreach (var submission in submissions)
+                {
+                    this.Data.Submissions.Delete(submission.Id);
+                }
+
+                var resources = problem.Resources;
+                foreach (var resource in resources)
+                {
+                    this.Data.Resources.Delete(resource.Id);
+                }
             }
 
             this.Data.SaveChanges();