Added backend functionality

WorkTime.Defaults/DataResult.cs

@@ -0,0 +1,83 @@
+using Microsoft.AspNetCore.Http;
+using Microsoft.AspNetCore.Http.HttpResults;
+using Microsoft.AspNetCore.Mvc;
+
+namespace WorkTime.Defaults;
+
+public class DataResult<TResult, TError>
+    where TResult : notnull
+    where TError : notnull {
+    public TResult? Content { get; }
+    public TError? Error { get; }
+    
+    public bool IsSuccessful => Error is null && Content is not null;
+
+    public IResult HttpResult => ToHttpResult(this);
+
+    public DataResult(TResult result) {
+        Content = result;
+    }
+
+    public DataResult(TError error) {
+        Error = error;
+    }
+
+    public static IResult ToHttpResult(DataResult<TResult, TError> dataResult) {
+        if (dataResult.Content is bool content)
+            return content ? Results.Ok() : Results.BadRequest();
+        
+        if (dataResult.IsSuccessful)
+            return Results.Ok(dataResult.Content);
+
+        if (dataResult.Error is ValidationProblemDetails validationProblem)
+            return Results.ValidationProblem(
+                validationProblem.Errors,
+                validationProblem.Detail,
+                validationProblem.Instance,
+                validationProblem.Status,
+                validationProblem.Title,
+                validationProblem.Type);
+
+        if (dataResult.Error is ProblemDetails problem)
+            return Results.Problem(problem);
+        
+        if (typeof(TError).IsAssignableTo(typeof(IResult)))
+            return dataResult.Error as IResult ?? Results.Problem();
+
+        return Results.Problem();
+    }
+
+    public static implicit operator DataResult<TResult, TError>(TResult result) {
+        return new DataResult<TResult, TError>(result);
+    }
+
+    public static implicit operator DataResult<TResult, TError>(TError error) {
+        return new DataResult<TResult, TError>(error);
+    }
+}
+
+public class DataResult<TResult> : DataResult<TResult, Exception> where TResult : notnull {
+    public DataResult(TResult result) : base(result) { }
+    public DataResult(Exception error) : base(error) { }
+
+    public static implicit operator DataResult<TResult>(TResult result) {
+        return new DataResult<TResult>(result);
+    }
+
+    public static implicit operator DataResult<TResult>(Exception error) {
+        return new DataResult<TResult>(error);
+    }
+}
+
+public class DataResult : DataResult<bool> {
+    public DataResult(bool result) : base(result) { }
+    public DataResult(Exception error) : base(error) { }
+    
+    public static implicit operator DataResult(bool result) {
+        return new DataResult(result);
+    }
+    
+    public static implicit operator DataResult(Exception error) {
+        return new DataResult(error);
+    }
+}