// Copyright (c) .NET Foundation. 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.IO;
using System.Threading.Tasks;
using System.Xml.Linq;
using Microsoft.AspNetCore.Server.IIS.FunctionalTests.Utilities;
using Microsoft.AspNetCore.Server.IntegrationTesting;
using Microsoft.AspNetCore.Server.IntegrationTesting.IIS;
using Microsoft.AspNetCore.Testing.xunit;
using Microsoft.Extensions.Logging;
using Xunit;

namespace Microsoft.AspNetCore.Server.IISIntegration.FunctionalTests
{
    [Collection(PublishedSitesCollection.Name)]
    public class MultiApplicationTests : IISFunctionalTestBase
    {
        private readonly PublishedSitesFixture _fixture;

        private PublishedApplication _publishedApplication;
        private PublishedApplication _rootApplication;

        public MultiApplicationTests(PublishedSitesFixture fixture)
        {
            _fixture = fixture;
        }

        [ConditionalFact]
        public async Task RunsTwoOutOfProcessApps()
        {
            var parameters = _fixture.GetBaseDeploymentParameters(HostingModel.OutOfProcess, publish: true);
            parameters.ServerConfigActionList.Add(DuplicateApplication);
            var result = await DeployAsync(parameters);
            var id1 = await result.HttpClient.GetStringAsync("/app1/ProcessId");
            var id2 = await result.HttpClient.GetStringAsync("/app2/ProcessId");
            Assert.NotEqual(id2, id1);
        }

        [ConditionalFact]
        public async Task FailsAndLogsWhenRunningTwoInProcessApps()
        {
            var parameters = _fixture.GetBaseDeploymentParameters(HostingModel.InProcess, publish: true);
            parameters.ServerConfigActionList.Add(DuplicateApplication);
            var result = await DeployAsync(parameters);
            var result1 = await result.HttpClient.GetAsync("/app1/HelloWorld");
            var result2 = await result.HttpClient.GetAsync("/app2/HelloWorld");
            Assert.Equal(200, (int)result1.StatusCode);
            Assert.Equal(500, (int)result2.StatusCode);
            StopServer();
            EventLogHelpers.VerifyEventLogEvent(TestSink, "Only one inprocess application is allowed per IIS application pool");
        }

        [ConditionalTheory]
        [InlineData(HostingModel.OutOfProcess)]
        [InlineData(HostingModel.InProcess)]
        public async Task FailsAndLogsEventLogForMixedHostingModel(HostingModel firstApp)
        {
            var parameters = _fixture.GetBaseDeploymentParameters(firstApp, publish: true);
            parameters.ServerConfigActionList.Add(DuplicateApplication);
            var result = await DeployAsync(parameters);

            // Modify hosting model of other app to be the opposite
            var otherApp = firstApp == HostingModel.InProcess ? HostingModel.OutOfProcess : HostingModel.InProcess;
            SetHostingModel(_publishedApplication.Path, otherApp);

            var result1 = await result.HttpClient.GetAsync("/app1/HelloWorld");
            var result2 = await result.HttpClient.GetAsync("/app2/HelloWorld");
            Assert.Equal(200, (int)result1.StatusCode);
            Assert.Equal(500, (int)result2.StatusCode);
            StopServer();
            EventLogHelpers.VerifyEventLogEvent(TestSink, "Mixed hosting model is not supported.");
        }

        private void SetHostingModel(string directory, HostingModel model)
        {
            var webConfigLocation = GetWebConfigLocation(directory);
            XDocument webConfig = XDocument.Load(webConfigLocation);
            webConfig.Root
                .GetOrAdd("system.webServer")
                .GetOrAdd("aspNetCore")
                .SetAttributeValue("hostingModel", model.ToString());
            webConfig.Save(webConfigLocation);
        }

        private void DuplicateApplication(XElement config, string contentRoot)
        {
            var siteElement = config
                .RequiredElement("system.applicationHost")
                .RequiredElement("sites")
                .RequiredElement("site");

            var application = siteElement
                .RequiredElement("application");

            application.SetAttributeValue("path", "/app1");

            var source = new DirectoryInfo(contentRoot);

            var destination = new DirectoryInfo(contentRoot + "anotherApp");
            destination.Create();
            Helpers.CopyFiles(source, destination, Logger);

            _publishedApplication = new PublishedApplication(destination.FullName, Logger);

            var newApplication = new XElement(application);
            newApplication.SetAttributeValue("path", "/app2");
            newApplication.RequiredElement("virtualDirectory")
                .SetAttributeValue("physicalPath", destination.FullName);

            siteElement.Add(newApplication);

            // IIS Express requires root application to exist
            var rootApplicationDirectory = new DirectoryInfo(contentRoot + "rootApp");
            rootApplicationDirectory.Create();

            _rootApplication = new PublishedApplication(rootApplicationDirectory.FullName, Logger);
            File.WriteAllText(GetWebConfigLocation(rootApplicationDirectory.FullName), "<configuration></configuration>");

            var rootApplication = new XElement(application);
            rootApplication.SetAttributeValue("path", "/");
            rootApplication.RequiredElement("virtualDirectory")
                .SetAttributeValue("physicalPath", rootApplicationDirectory.FullName);

            siteElement.Add(rootApplication);
        }

        private static string GetWebConfigLocation(string siteRoot)
        {
            return Path.Combine(siteRoot, "web.config");
        }

        public override void Dispose()
        {
            base.Dispose();
            _rootApplication.Dispose();
            _publishedApplication.Dispose();
        }
    }
}