using System;
using System.Collections.Generic;
using System.IO;
using System.Net;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Http;
using Ocelot.Configuration.File;
using Shouldly;
using TestStack.BDDfy;
using Xunit;

namespace Ocelot.AcceptanceTests
{
    public class UpstreamHostTests : IDisposable
    {
        private IWebHost _builder;
        private readonly Steps _steps;
        private string _downstreamPath;

        public UpstreamHostTests()
        {
            _steps = new Steps();
        }

        [Fact]
        public void should_return_response_200_with_simple_url_and_hosts_match()
        {
            var configuration = new FileConfiguration
            {
                ReRoutes = new List<FileReRoute>
                    {
                        new FileReRoute
                        {
                            DownstreamPathTemplate = "/",
                            DownstreamScheme = "http",
                            DownstreamHostAndPorts = new List<FileHostAndPort>
                            {
                                new FileHostAndPort
                                {
                                    Host = "localhost",
                                    Port = 51875,
                                }
                            },
                            UpstreamPathTemplate = "/",
                            UpstreamHttpMethod = new List<string> { "Get" },
                            UpstreamHost = "localhost"
                        }
                    }
            };

            this.Given(x => x.GivenThereIsAServiceRunningOn("http://localhost:51875", "/", 200, "Hello from Laura"))
                .And(x => _steps.GivenThereIsAConfiguration(configuration))
                .And(x => _steps.GivenOcelotIsRunning())
                .When(x => _steps.WhenIGetUrlOnTheApiGateway("/"))
                .Then(x => _steps.ThenTheStatusCodeShouldBe(HttpStatusCode.OK))
                .And(x => _steps.ThenTheResponseBodyShouldBe("Hello from Laura"))
                .BDDfy();
        }

        [Fact]
        public void should_return_response_200_with_simple_url_and_hosts_match_multiple_re_routes()
        {
            var configuration = new FileConfiguration
            {
                ReRoutes = new List<FileReRoute>
                {
                    new FileReRoute
                    {
                        DownstreamPathTemplate = "/",
                        DownstreamScheme = "http",
                        DownstreamHostAndPorts = new List<FileHostAndPort>
                        {
                            new FileHostAndPort
                            {
                                Host = "localhost",
                                Port = 51875,
                            }
                        },
                        UpstreamPathTemplate = "/",
                        UpstreamHttpMethod = new List<string> { "Get" },
                        UpstreamHost = "localhost"
                    },
                    new FileReRoute
                    {
                        DownstreamPathTemplate = "/",
                        DownstreamScheme = "http",
                        DownstreamHostAndPorts = new List<FileHostAndPort>
                        {
                            new FileHostAndPort
                            {
                                Host = "localhost",
                                Port = 50000,
                            }
                        },
                        UpstreamPathTemplate = "/",
                        UpstreamHttpMethod = new List<string> { "Get" },
                        UpstreamHost = "DONTMATCH"
                    }
                }
            };

            this.Given(x => x.GivenThereIsAServiceRunningOn("http://localhost:51875", "/", 200, "Hello from Laura"))
                .And(x => _steps.GivenThereIsAConfiguration(configuration))
                .And(x => _steps.GivenOcelotIsRunning())
                .When(x => _steps.WhenIGetUrlOnTheApiGateway("/"))
                .Then(x => _steps.ThenTheStatusCodeShouldBe(HttpStatusCode.OK))
                .And(x => _steps.ThenTheResponseBodyShouldBe("Hello from Laura"))
                .BDDfy();
        }

        [Fact]
        public void should_return_response_200_with_simple_url_and_hosts_match_multiple_re_routes_reversed()
        {
            var configuration = new FileConfiguration
            {
                ReRoutes = new List<FileReRoute>
                {
                    new FileReRoute
                    {
                        DownstreamPathTemplate = "/",
                        DownstreamScheme = "http",
                        DownstreamHostAndPorts = new List<FileHostAndPort>
                        {
                            new FileHostAndPort
                            {
                                Host = "localhost",
                                Port = 50000,
                            }
                        },
                        UpstreamPathTemplate = "/",
                        UpstreamHttpMethod = new List<string> { "Get" },
                        UpstreamHost = "DONTMATCH"
                    },
                    new FileReRoute
                    {
                        DownstreamPathTemplate = "/",
                        DownstreamScheme = "http",
                        DownstreamHostAndPorts = new List<FileHostAndPort>
                        {
                            new FileHostAndPort
                            {
                                Host = "localhost",
                                Port = 51875,
                            }
                        },
                        UpstreamPathTemplate = "/",
                        UpstreamHttpMethod = new List<string> { "Get" },
                        UpstreamHost = "localhost"
                    }
                }
            };

            this.Given(x => x.GivenThereIsAServiceRunningOn("http://localhost:51875", "/", 200, "Hello from Laura"))
                .And(x => _steps.GivenThereIsAConfiguration(configuration))
                .And(x => _steps.GivenOcelotIsRunning())
                .When(x => _steps.WhenIGetUrlOnTheApiGateway("/"))
                .Then(x => _steps.ThenTheStatusCodeShouldBe(HttpStatusCode.OK))
                .And(x => _steps.ThenTheResponseBodyShouldBe("Hello from Laura"))
                .BDDfy();
        }

        [Fact]
        public void should_return_response_200_with_simple_url_and_hosts_match_multiple_re_routes_reversed_with_no_host_first()
        {
            var configuration = new FileConfiguration
            {
                ReRoutes = new List<FileReRoute>
                {
                    new FileReRoute
                    {
                        DownstreamPathTemplate = "/",
                        DownstreamScheme = "http",
                        DownstreamHostAndPorts = new List<FileHostAndPort>
                        {
                            new FileHostAndPort
                            {
                                Host = "localhost",
                                Port = 50000,
                            }
                        },
                        UpstreamPathTemplate = "/",
                        UpstreamHttpMethod = new List<string> { "Get" },
                    },
                    new FileReRoute
                    {
                        DownstreamPathTemplate = "/",
                        DownstreamScheme = "http",
                        DownstreamHostAndPorts = new List<FileHostAndPort>
                        {
                            new FileHostAndPort
                            {
                                Host = "localhost",
                                Port = 51875,
                            }
                        },
                        UpstreamPathTemplate = "/",
                        UpstreamHttpMethod = new List<string> { "Get" },
                        UpstreamHost = "localhost"
                    }
                }
            };

            this.Given(x => x.GivenThereIsAServiceRunningOn("http://localhost:51875", "/", 200, "Hello from Laura"))
                .And(x => _steps.GivenThereIsAConfiguration(configuration))
                .And(x => _steps.GivenOcelotIsRunning())
                .When(x => _steps.WhenIGetUrlOnTheApiGateway("/"))
                .Then(x => _steps.ThenTheStatusCodeShouldBe(HttpStatusCode.OK))
                .And(x => _steps.ThenTheResponseBodyShouldBe("Hello from Laura"))
                .BDDfy();
        }

        [Fact]
        public void should_return_response_404_with_simple_url_and_hosts_dont_match()
        {
            var configuration = new FileConfiguration
            {
                ReRoutes = new List<FileReRoute>
                {
                    new FileReRoute
                    {
                        DownstreamPathTemplate = "/",
                        DownstreamScheme = "http",
                        DownstreamHostAndPorts = new List<FileHostAndPort>
                        {
                            new FileHostAndPort
                            {
                                Host = "localhost",
                                Port = 51875,
                            }
                        },
                        UpstreamPathTemplate = "/",
                        UpstreamHttpMethod = new List<string> { "Get" },
                        UpstreamHost = "127.0.0.20:5000"
                    }
                }
            };

            this.Given(x => x.GivenThereIsAServiceRunningOn("http://localhost:51875", "/", 200, "Hello from Laura"))
                .And(x => _steps.GivenThereIsAConfiguration(configuration))
                .And(x => _steps.GivenOcelotIsRunning())
                .When(x => _steps.WhenIGetUrlOnTheApiGateway("/"))
                .Then(x => _steps.ThenTheStatusCodeShouldBe(HttpStatusCode.NotFound))
                .BDDfy();
        }

        private void GivenThereIsAServiceRunningOn(string baseUrl, string basePath, int statusCode, string responseBody)
        {
            _builder = new WebHostBuilder()
                .UseUrls(baseUrl)
                .UseKestrel()
                .UseContentRoot(Directory.GetCurrentDirectory())
                .UseIISIntegration()
                .Configure(app =>
                {
                    app.UsePathBase(basePath);
                    app.Run(async context =>
                    {   
                        _downstreamPath = !string.IsNullOrEmpty(context.Request.PathBase.Value) ? context.Request.PathBase.Value : context.Request.Path.Value;

                        if(_downstreamPath != basePath)
                        {
                            context.Response.StatusCode = statusCode;
                            await context.Response.WriteAsync("downstream path didnt match base path");
                        }
                        else
                        {
                            context.Response.StatusCode = statusCode;
                            await context.Response.WriteAsync(responseBody);
                        }
                    });
                })
                .Build();

            _builder.Start();
        }

        internal void ThenTheDownstreamUrlPathShouldBe(string expectedDownstreamPath)
        {
            _downstreamPath.ShouldBe(expectedDownstreamPath);
        }

        public void Dispose()
        {
            _builder?.Dispose();
            _steps.Dispose();
        }
    }
}