// Copyright (c) Microsoft Open Technologies, Inc. All rights reserved.
// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.

using System;
using System.Collections.Generic;
using System.IO;
using System.Threading.Tasks;
using Microsoft.AspNet.Http;
using Microsoft.AspNet.Http.Core;
using Microsoft.AspNet.Http.Core.Collections;
using Microsoft.AspNet.Routing;
using Microsoft.AspNet.Testing;
using Microsoft.AspNet.WebUtilities;
using Microsoft.Framework.OptionsModel;
using Moq;
using Xunit;

namespace Microsoft.AspNet.Mvc
{
    public class CreatedAtActionResultTests
    {
        [Fact]
        public async Task CreatedAtActionResult_ReturnsStatusCode_SetsLocationHeader()
        {
            // Arrange
            var expectedUrl = "testAction";
            var httpContext = GetHttpContext();
            var actionContext = GetActionContext(httpContext);
            var urlHelper = GetMockUrlHelper(expectedUrl);

            // Act
            var result = new CreatedAtActionResult(
                actionName: expectedUrl,
                controllerName: null,
                routeValues: null,
                value: null);

            result.UrlHelper = urlHelper;
            await result.ExecuteResultAsync(actionContext);

            // Assert
            Assert.Equal(StatusCodes.Status201Created, httpContext.Response.StatusCode);
            Assert.Equal(expectedUrl, httpContext.Response.Headers["Location"]);
        }

        [Fact]
        public async Task CreatedAtActionResult_ThrowsOnNullUrl()
        {
            // Arrange
            var httpContext = GetHttpContext();
            var actionContext = GetActionContext(httpContext);
            var urlHelper = GetMockUrlHelper(returnValue: null);

            var result = new CreatedAtActionResult(
                actionName: null,
                controllerName: null,
                routeValues: null,
                value: null);

            result.UrlHelper = urlHelper;

            // Act & Assert
            await ExceptionAssert.ThrowsAsync<InvalidOperationException>(
                async () => await result.ExecuteResultAsync(actionContext),
            "No route matches the supplied values.");
        }

        private static HttpResponse GetMockedHttpResponseObject()
        {
            var stream = new MemoryStream();
            var httpResponse = new Mock<HttpResponse>();
            httpResponse.SetupProperty(o => o.StatusCode);
            httpResponse.Setup(o => o.Headers).Returns(
                new HeaderDictionary(new Dictionary<string, string[]>()));
            httpResponse.SetupGet(o => o.Body).Returns(stream);
            return httpResponse.Object;
        }

        private static ActionContext GetActionContext(HttpContext httpContext)
        {
            var routeData = new RouteData();
            routeData.Routers.Add(Mock.Of<IRouter>());

            return new ActionContext(httpContext,
                                    routeData,
                                    new ActionDescriptor());
        }

        private static HttpContext GetHttpContext()
        {
            var httpContext = new DefaultHttpContext();
            httpContext.Request.PathBase = new PathString("");
            httpContext.Response.Body = new MemoryStream();
            var services = new Mock<IServiceProvider>();
            services.Setup(p => p.GetService(typeof(IOutputFormattersProvider))).Returns(new TestOutputFormatterProvider());
            httpContext.RequestServices = services.Object;
            var options = new Mock<IOptions<MvcOptions>>();
            options.SetupGet(o => o.Options)
                       .Returns(new MvcOptions());
            services.Setup(p => p.GetService(typeof(IOptions<MvcOptions>)))
                       .Returns(options.Object);

            return httpContext;
        }

        private static IUrlHelper GetMockUrlHelper(string returnValue)
        {
            var urlHelper = new Mock<IUrlHelper>();
            urlHelper.Setup(o => o.Action(It.IsAny<UrlActionContext>())).Returns(returnValue);

            return urlHelper.Object;
        }

        private class TestOutputFormatterProvider : IOutputFormattersProvider
        {
            public IReadOnlyList<IOutputFormatter> OutputFormatters
            {
                get
                {
                    return new List<IOutputFormatter>()
                            {
                                new StringOutputFormatter(),
                                new JsonOutputFormatter()
                            };
                }
            }
        }
    }
}