// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.

using System;
using System.Collections.Generic;
using Microsoft.AspNetCore.Mvc.ModelBinding;
using Xunit;

namespace Microsoft.AspNetCore.Mvc
{
    public class ValidationProblemDetailsTest
    {
        [Fact]
        public void Constructor_SetsTitle()
        {
            // Arrange & Act
            var problemDescription = new ValidationProblemDetails();

            // Assert
            Assert.Equal("One or more validation errors occurred.", problemDescription.Title);
            Assert.Empty(problemDescription.Errors);
        }

        [Fact]
        public void Constructor_SerializesErrorsFromModelStateDictionary()
        {
            // Arrange
            var modelStateDictionary = new ModelStateDictionary();
            modelStateDictionary.AddModelError("key1", "error1");
            modelStateDictionary.SetModelValue("key2", new object(), "value");
            modelStateDictionary.AddModelError("key3", "error2");
            modelStateDictionary.AddModelError("key3", "error3");

            // Act
            var problemDescription = new ValidationProblemDetails(modelStateDictionary);

            // Assert
            Assert.Equal("One or more validation errors occurred.", problemDescription.Title);
            Assert.Collection(
                problemDescription.Errors,
                item =>
                {
                    Assert.Equal("key1", item.Key);
                    Assert.Equal(new[] { "error1" }, item.Value);
                },
                item =>
                {
                    Assert.Equal("key3", item.Key);
                    Assert.Equal(new[] { "error2", "error3" }, item.Value);
                });
        }

        [Fact]
        public void Constructor_SerializesErrorsFromModelStateDictionary_AddsDefaultMessage()
        {
            // Arrange
            var modelStateDictionary = new ModelStateDictionary();
            var provider = new EmptyModelMetadataProvider();
            var metadata = provider.GetMetadataForProperty(typeof(string), nameof(string.Length));
            modelStateDictionary.AddModelError("unsafeError",
                new Exception("This message should not be returned to clients"),
                metadata);

            // Act
            var problemDescription = new ValidationProblemDetails(modelStateDictionary);

            // Assert
            Assert.Equal("One or more validation errors occurred.", problemDescription.Title);
            Assert.Collection(
                problemDescription.Errors,
                item =>
                {
                    Assert.Equal("unsafeError", item.Key);
                    Assert.Equal(new[] { "The input was not valid." }, item.Value);
                });
        }

        [Fact]
        public void Constructor_CopiesPassedInDictionary()
        {
            // Arrange
            var errors = new Dictionary<string, string[]>
            {
                ["key1"] = new[] { "error1", "error2" },
                ["key2"] = new[] { "error3", },
            };

            // Act
            var problemDescription = new ValidationProblemDetails(errors);

            // Assert
            Assert.Equal("One or more validation errors occurred.", problemDescription.Title);
            Assert.Collection(
                problemDescription.Errors,
                item =>
                {
                    Assert.Equal("key1", item.Key);
                    Assert.Equal(new[] { "error1", "error2" }, item.Value);
                },
                item =>
                {
                    Assert.Equal("key2", item.Key);
                    Assert.Equal(new[] { "error3" }, item.Value);
                });
        }
    }
}
