// 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 System.IO;
using System.Text;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Routing;
using Microsoft.AspNetCore.Testing;
using Microsoft.Extensions.DependencyInjection;
using Moq;
using Xunit;

namespace Microsoft.AspNetCore.Http.Result
{
    public class AcceptedAtRouteResultTests
    {
        [Fact]
        public async Task ExecuteResultAsync_FormatsData()
        {
            // Arrange
            var url = "testAction";
            var linkGenerator = new TestLinkGenerator { Url = url };
            var httpContext = GetHttpContext(linkGenerator);
            var stream = new MemoryStream();
            httpContext.Response.Body = stream;

            var routeValues = new RouteValueDictionary(new Dictionary<string, string>()
            {
                { "test", "case" },
                { "sample", "route" }
            });

            // Act
            var result = new AcceptedAtRouteResult(
                routeName: "sample",
                routeValues: routeValues,
                value: "Hello world");
            await result.ExecuteAsync(httpContext);

            // Assert
            var response = Encoding.UTF8.GetString(stream.ToArray());
            Assert.Equal("\"Hello world\"", response);
        }

        public static TheoryData<object> AcceptedAtRouteData
        {
            get
            {
                return new TheoryData<object>
                {
                    null,
                    new Dictionary<string, string>()
                    {
                        { "hello", "world" }
                    },
                    new RouteValueDictionary(
                        new Dictionary<string, string>()
                        {
                            { "test", "case" },
                            { "sample", "route" }
                        }),
                    };
            }
        }

        [Theory]
        [MemberData(nameof(AcceptedAtRouteData))]
        public async Task ExecuteResultAsync_SetsStatusCodeAndLocationHeader(object values)
        {
            // Arrange
            var expectedUrl = "testAction";
            var linkGenerator = new TestLinkGenerator { Url = expectedUrl };
            var httpContext = GetHttpContext(linkGenerator);

            // Act
            var result = new AcceptedAtRouteResult(routeValues: values, value: null);
            await result.ExecuteAsync(httpContext);

            // Assert
            Assert.Equal(StatusCodes.Status202Accepted, httpContext.Response.StatusCode);
            Assert.Equal(expectedUrl, httpContext.Response.Headers["Location"]);
        }

        [Fact]
        public async Task ExecuteResultAsync_ThrowsIfRouteUrlIsNull()
        {
            // Arrange
            var linkGenerator = new TestLinkGenerator();
            var httpContext = GetHttpContext(linkGenerator);

            // Act
            var result = new AcceptedAtRouteResult(
                routeName: null,
                routeValues: new Dictionary<string, object>(),
                value: null);

            // Assert
            await ExceptionAssert.ThrowsAsync<InvalidOperationException>(() =>
                result.ExecuteAsync(httpContext),
                "No route matches the supplied values.");
        }

        private static HttpContext GetHttpContext(LinkGenerator linkGenerator)
        {
            var httpContext = new DefaultHttpContext();
            httpContext.RequestServices = CreateServices(linkGenerator);
            return httpContext;
        }

        private static IServiceProvider CreateServices(LinkGenerator linkGenerator)
        {
            var services = new ServiceCollection();
            services.AddLogging();
            services.AddSingleton(linkGenerator);
            return services.BuildServiceProvider();
        }
    }
}