implement re-evaluation requests on prechecks

SPTInstaller/Controllers/InstallController.cs

@@ -11,8 +11,10 @@ namespace SPTInstaller.Controllers;
 
 public class InstallController
 {
+    public event EventHandler RecheckRequested = delegate { };
     public event EventHandler<IProgressableTask> TaskChanged = delegate { };
 
+    private bool _installRunning = false;
     private IPreCheck[] _preChecks { get; set; }
     private IProgressableTask[] _tasks { get; set; }
 
@@ -20,6 +22,22 @@ public class InstallController
     {
         _tasks = tasks;
         _preChecks = preChecks;
+        
+        _preChecks.ForEach(x => x.ReeevaluationRequested += (s, e) =>
+        {
+            if (s is IPreCheck preCheck)
+            {
+                Log.Information($"{preCheck.Name}: requested re-evaluation");
+                
+                if (_installRunning)
+                {
+                    Log.Warning("Install is running, re-evaluation denied (how did you do this?)");
+                    return;
+                }
+
+                RecheckRequested?.Invoke(this, null);
+            }
+        });
     }
 
     public async Task<IResult> RunPreChecks()
@@ -51,6 +69,8 @@ public class InstallController
 
     public async Task<IResult> RunTasks()
     {
+        _installRunning = true;
+        
         Log.Information("-<>--<>- Running Installer Tasks -<>--<>-");
 
         foreach (var task in _tasks)

SPTInstaller/Interfaces/IPreCheck.cs

@@ -10,6 +10,7 @@ public interface IPreCheck
     public bool IsRequired { get; }
     public string PreCheckDetails { get; }
     public StatusSpinner.SpinnerState State { get; set; }
+    public event EventHandler ReeevaluationRequested;
 
     public Task<IResult> RunCheck();
 }

SPTInstaller/Models/PreCheckBase.cs

@@ -8,6 +8,7 @@ namespace SPTInstaller.Models;
 
 public abstract class PreCheckBase : ReactiveObject, IPreCheck
 {
+    public event EventHandler ReeevaluationRequested = delegate {  };
     private string _id;
     public string Id
     {
@@ -84,6 +85,14 @@ public abstract class PreCheckBase : ReactiveObject, IPreCheck
             (_, _)         => StatusSpinner.SpinnerState.Error
         };
 
+    /// <summary>
+    /// Request pre-checks to be re-evaluated
+    /// </summary>
+    public void RequestReevaluation()
+    {
+        ReeevaluationRequested?.Invoke(this, null);
+    }
+
     public async Task<IResult> RunCheck()
     {
         State = StatusSpinner.SpinnerState.Running;

SPTInstaller/ViewModels/PreChecksViewModel.cs

@@ -79,11 +79,25 @@ public class PreChecksViewModel : ViewModelBase
         set => this.RaiseAndSetIfChanged(ref _installButtonCheckState, value);
     }
 
+    private void ReCheckRequested(object? sender, EventArgs e)
+    {
+        Task.Run(async () =>
+        {
+            if (sender is InstallController installer)
+            {
+                var result = await installer.RunPreChecks();
+                AllowInstall = result.Succeeded;
+            }
+        });
+    }
+
     public PreChecksViewModel(IScreen host) : base(host)
     {
         var data = ServiceHelper.Get<InternalData?>();
         var installer = ServiceHelper.Get<InstallController?>();
 
+        installer.RecheckRequested += ReCheckRequested;
+
         InstallButtonText = "Please wait ...";
         InstallButtonCheckState = StatusSpinner.SpinnerState.Pending;
 
@@ -158,6 +172,7 @@ public class PreChecksViewModel : ViewModelBase
         {
             UpdateInfo.ShowCard = false;
             Log.Logger.Information("Opening Detailed PreCheck View");
+            installer.RecheckRequested -= ReCheckRequested;
             NavigateTo(new DetailedPreChecksViewModel(HostScreen));
         });