// 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.Threading.Tasks;
using Microsoft.AspNet.Builder;
using Microsoft.AspNet.TestHost;
using Microsoft.Framework.DependencyInjection;
using RazorInstrumentationWebSite;
using Xunit;

namespace Microsoft.AspNet.Mvc.FunctionalTests
{
    public class RazorInstrumentationTests
    {
        private readonly IServiceProvider _services = TestHelper.CreateServices("RazorInstrumentationWebsite");
        private readonly Action<IApplicationBuilder> _app = new Startup().Configure;

        public static IEnumerable<object[]> InstrumentationData
        {
            get
            {
                var expected = string.Join(Environment.NewLine,
                                           @"<div>",
                                           @"2147483647",
                                           "",
                                           @"viewstart-content",
                                           @"<p class=""Hello world"">",
                                           @"page-content",
                                           @"</p>",
                                           @"</div>");

                var expectedLineMappings = new[]
                {
                    Tuple.Create(93, 2, true),
                    Tuple.Create(96, 16, false),
                    Tuple.Create(112, 2, true),
                    Tuple.Create(0, 2, true),
                    Tuple.Create(2, 8, true),
                    Tuple.Create(10, 16, false),
                    Tuple.Create(26, 1, true),
                    Tuple.Create(27, 21, true),
                    Tuple.Create(0, 7, true),
                    Tuple.Create(8, 12, false),
                    Tuple.Create(20, 2, true),
                    Tuple.Create(23, 12, false),
                    Tuple.Create(35, 8, true),
                };

                yield return new object[] { "FullPath", expected, expectedLineMappings };
                yield return new object[] { "ViewDiscoveryPath", expected, expectedLineMappings };

                var expected2 = string.Join(Environment.NewLine,
                                            "<div>",
                                            "2147483647",
                                            "",
                                            "viewstart-content",
                                            "view-with-partial-content",
                                            "",
                                            @"<p class=""class"">partial-content</p>",
                                            "",
                                            @"<p class=""class"">partial-content</p>",
                                            "</div>");
                var expectedLineMappings2 = new[]
                {
                    Tuple.Create(93, 2, true),
                    Tuple.Create(96, 16, false),
                    Tuple.Create(112, 2, true),
                    Tuple.Create(0, 27, true),
                    Tuple.Create(28, 39, false),
                    // Html.PartialAsync()
                    Tuple.Create(29, 4, true),
                    Tuple.Create(33, 8, true),
                    Tuple.Create(41, 4, false),
                    Tuple.Create(45, 1, true),
                    Tuple.Create(46, 20, true),
                    Tuple.Create(67, 2, true),
                    // Html.RenderPartial()
                    Tuple.Create(29, 4, true),
                    Tuple.Create(33, 8, true),
                    Tuple.Create(41, 4, false),
                    Tuple.Create(45, 1, true),
                    Tuple.Create(46, 20, true),
                    Tuple.Create(0, 7, true),
                    Tuple.Create(8, 12, false),
                    Tuple.Create(20, 2, true),
                    Tuple.Create(23, 12, false),
                    Tuple.Create(35, 8, true)
                };
                yield return new object[] { "ViewWithPartial", expected2, expectedLineMappings2 };
            }
        }

        [Theory]
        [MemberData(nameof(InstrumentationData))]
        public async Task ViewsAreServedWithoutInstrumentationByDefault(string actionName,
                                                                        string expected,
                                                                        IEnumerable<Tuple<int, int, bool>> expectedLineMappings)
        {
            // Arrange
            var context = new TestPageExecutionContext();
            var services = GetServiceProvider(context);
            var server = TestServer.Create(services, _app);
            var client = server.CreateClient();

            // Act
            var body = await client.GetStringAsync("http://localhost/Home/" + actionName);

            // Assert
            Assert.Equal(expected, body.Trim());
            Assert.Empty(context.Values);
        }

        [Theory]
        [MemberData(nameof(InstrumentationData))]
        public async Task ViewsAreInstrumentedWhenPageExecutionListenerFeatureIsEnabled(string actionName,
                                                                                        string expected,
                                                                                        IEnumerable<Tuple<int, int, bool>> expectedLineMappings)
        {
            // Arrange
            var context = new TestPageExecutionContext();
            var services = GetServiceProvider(context);
            var server = TestServer.Create(services, _app);
            var client = server.CreateClient();
            client.DefaultRequestHeaders.Add("ENABLE-RAZOR-INSTRUMENTATION", "true");

            // Act
            var body = await client.GetStringAsync("http://localhost/Home/" + actionName);

            // Assert
            Assert.Equal(expected, body.Trim());
            Assert.Equal(expectedLineMappings, context.Values);
        }

        [Theory]
        [MemberData(nameof(InstrumentationData))]
        public async Task ViewsCanSwitchFromRegularToInstrumented(string actionName,
                                                                  string expected,
                                                                  IEnumerable<Tuple<int, int, bool>> expectedLineMappings)
        {
            // Arrange - 1
            var context = new TestPageExecutionContext();
            var services = GetServiceProvider(context);
            var server = TestServer.Create(services, _app);
            var client = server.CreateClient();

            // Act - 1
            var body = await client.GetStringAsync("http://localhost/Home/" + actionName);

            // Assert - 1
            Assert.Equal(expected, body.Trim());
            Assert.Empty(context.Values);

            // Arrange - 2
            client.DefaultRequestHeaders.Add("ENABLE-RAZOR-INSTRUMENTATION", "true");

            // Act - 2
            body = await client.GetStringAsync("http://localhost/Home/" + actionName);

            // Assert - 2
            Assert.Equal(expected, body.Trim());
            Assert.Equal(expectedLineMappings, context.Values);
        }

        [Fact]
        public async Task SwitchingFromNonInstrumentedToInstrumentedWorksForLayoutAndViewStarts()
        {
            // Arrange - 1
            var expectedLineMappings = new[]
            {
                Tuple.Create(93, 2, true),
                Tuple.Create(96, 16, false),
                Tuple.Create(112, 2, true),
                Tuple.Create(0, 2, true),
                Tuple.Create(2, 8, true),
                Tuple.Create(10, 16, false),
                Tuple.Create(26, 1, true),
                Tuple.Create(27, 21, true),
                Tuple.Create(0, 7, true),
                Tuple.Create(8, 12, false),
                Tuple.Create(20, 2, true),
                Tuple.Create(23, 12, false),
                Tuple.Create(35, 8, true),
            };
            var context = new TestPageExecutionContext();
            var services = GetServiceProvider(context);
            var server = TestServer.Create(services, _app);
            var client = server.CreateClient();

            // Act - 1
            var body = await client.GetStringAsync("http://localhost/Home/FullPath");

            // Assert - 1
            Assert.Empty(context.Values);

            // Arrange - 2
            client.DefaultRequestHeaders.Add("ENABLE-RAZOR-INSTRUMENTATION", "true");

            // Act - 2
            body = await client.GetStringAsync("http://localhost/Home/ViewDiscoveryPath");

            // Assert - 2
            Assert.Equal(expectedLineMappings, context.Values);
        }

        private IServiceProvider GetServiceProvider(TestPageExecutionContext pageExecutionContext)
        {
            var services = new ServiceCollection();
            services.AddInstance(pageExecutionContext);
            return TestHelper.CreateServices("RazorInstrumentationWebsite", services);
        }
    }
}