// 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.Linq;
using System.Text;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Routing;
using Microsoft.AspNetCore.Routing.Internal;
using Microsoft.AspNetCore.Routing.Patterns;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.DependencyInjection.Extensions;

namespace RoutingSandbox
{
    public class UseEndpointRoutingStartup
    {
        private static readonly byte[] _homePayload = Encoding.UTF8.GetBytes("Endpoint Routing sample endpoints:" + Environment.NewLine + "/plaintext");
        private static readonly byte[] _plainTextPayload = Encoding.UTF8.GetBytes("Plain text!");

        public void ConfigureServices(IServiceCollection services)
        {
            services.AddRouting();
        }

        public void Configure(IApplicationBuilder app)
        {
            app.UseEndpointRouting(builder =>
            {
                builder.MapHello("/helloworld", "World");

                builder.MapHello("/helloworld-secret", "Secret World")
                    .RequireAuthorization("swordfish");

                builder.MapGet(
                    "/",
                    (httpContext) =>
                    {
                        var dataSource = httpContext.RequestServices.GetRequiredService<EndpointDataSource>();

                        var sb = new StringBuilder();
                        sb.AppendLine("Endpoints:");
                        foreach (var endpoint in dataSource.Endpoints.OfType<RouteEndpoint>().OrderBy(e => e.RoutePattern.RawText, StringComparer.OrdinalIgnoreCase))
                        {
                            sb.AppendLine($"- {endpoint.RoutePattern.RawText}");
                        }

                        var response = httpContext.Response;
                        response.StatusCode = 200;
                        response.ContentType = "text/plain";
                        return response.WriteAsync(sb.ToString());
                    });
                builder.MapGet(
                    "/plaintext",
                    (httpContext) =>
                    {
                        var response = httpContext.Response;
                        var payloadLength = _plainTextPayload.Length;
                        response.StatusCode = 200;
                        response.ContentType = "text/plain";
                        response.ContentLength = payloadLength;
                        return response.Body.WriteAsync(_plainTextPayload, 0, payloadLength);
                    });
                builder.MapGet(
                    "/graph",
                    "DFA Graph",
                    (httpContext) =>
                    {
                        using (var writer = new StreamWriter(httpContext.Response.Body, Encoding.UTF8, 1024, leaveOpen: true))
                        {
                            var graphWriter = httpContext.RequestServices.GetRequiredService<DfaGraphWriter>();
                            var dataSource = httpContext.RequestServices.GetRequiredService<CompositeEndpointDataSource>();
                            graphWriter.Write(dataSource, writer);
                        }

                        return Task.CompletedTask;
                    });
            });

            app.UseStaticFiles();
			
			app.UseAuthorization();

            app.UseEndpoint();
        }
    }
}