using System.Text;
using System;
using Microsoft.AspNetCore.Authentication.JwtBearer;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using Microsoft.Extensions.Logging;
using Microsoft.IdentityModel.Tokens;
using NLog.Extensions.Logging;
using NLog;
using gswi.Configuration;
using gswi.CredentialManager;
using gswi.Data;
using gswi.Data.Repositories;
using gswi.Filters;
using gswi.Interface.Repositories;
using gswi.Interface.Services;
using gswi.Service;
using gswi.SMTP.Interface;
using gswi.SMTP.Service;
using gswi.SignalR;
using Microsoft.AspNetCore.HttpOverrides;

namespace gswi
{
    public class Startup
    {
        public IConfiguration Configuration { get; }
        private static Logger _logger = LogManager.GetCurrentClassLogger();

        public Startup(IHostEnvironment env)
        {
            try
            {
                var environmentName = Environment.GetEnvironmentVariable("ASPNETCORE_ENVIRONMENT");
                if (string.IsNullOrEmpty(environmentName))
                    environmentName = "production";
                var builder = new ConfigurationBuilder().SetBasePath(env.ContentRootPath)
                .AddJsonFile("appsettings.json", optional: true, reloadOnChange: true)
                .AddJsonFile($"appsettings.{env.EnvironmentName}.json", optional: true)
                .AddJsonFile($"appsettings.{System.Net.Dns.GetHostName()}.json", optional: true)
                .AddEnvironmentVariables();

                Configuration = builder.Build();
            }
            catch (Exception e)
            {
                _logger.Error(e);
            }
        }

        // This method gets called by the runtime. Use this method to add services to the container.
        public void ConfigureServices(IServiceCollection services)
        {
            services.AddLogging(builder =>
            {
                builder.ClearProviders();
                builder.AddConfiguration(Configuration.GetSection("Logging"));
                builder.AddNLog();
                builder.AddConsole();
            });

            var frontend = GetTypedSettingsFromSection<FrontendSettings>("Frontend");

            services.AddCors(options =>
            {
                options.AddPolicy("CorsPolicy", builder => builder.WithOrigins(frontend.URL)
                    .AllowAnyHeader()
                    .AllowAnyMethod()
                    .AllowCredentials()
                    .SetIsOriginAllowed((host) => true));
            });

            var dbSettings = GetTypedSettingsFromSection<DatabaseSettings>("Database");
            var authSettings = GetTypedSettingsFromSection<AuthentificationSettings>("Authentification");
            var emailSettings = GetTypedSettingsFromSection<EMailSettings>("EMail");
            var apiSettings = GetTypedSettingsFromSection<APISettings>("API");
            emailSettings.Credentials = Base64.Decode(emailSettings.Credentials);

            services.AddSingleton(dbSettings);
            services.AddSingleton(authSettings);
            services.AddSingleton(emailSettings);
            services.AddSingleton(apiSettings);
            services.AddSingleton(GetTypedSettingsFromSection<FrontendSettings>("Frontend"));

            services.AddDbContextPool<DatabaseContext>(opt => opt.UseMySql(
                Base64.DecodeConnectionString(dbSettings.ConnectionString, dbSettings.Credentials),
                new MySqlServerVersion(new Version(10, 3, 32))
            ));

            services.AddTransient<IAuthService, AuthServiceImpl>();
            services.AddTransient<ISMTPClient, SMTPClientImpl>();

            services.AddScoped<IUnitOfWork>((s) => s.GetRequiredService<DatabaseContext>());
            services.AddScoped<IAuthUserRepository>((s) => new AuthUserRepositoryImpl((DatabaseContext)s.GetService<IUnitOfWork>()));

            services.AddSignalR();

            services.AddAuthentication(opt =>
            {
                opt.DefaultAuthenticateScheme = JwtBearerDefaults.AuthenticationScheme;
                opt.DefaultChallengeScheme = JwtBearerDefaults.AuthenticationScheme;
            }).AddJwtBearer(opt =>
            {
                opt.RequireHttpsMetadata = false;
                opt.SaveToken = true;
                opt.TokenValidationParameters = new TokenValidationParameters
                {
                    ValidateIssuer = true,
                    ValidateAudience = true,
                    ValidateLifetime = true,
                    ValidateIssuerSigningKey = true,

                    ValidIssuer = authSettings.Issuer,
                    ValidAudience = authSettings.Audience,
                    IssuerSigningKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(authSettings.SecretKey))
                };
            });

            services.AddControllers()
                .AddNewtonsoftJson(options =>
                {
                    options.SerializerSettings.ReferenceLoopHandling = Newtonsoft.Json.ReferenceLoopHandling.Ignore;
                    // options.SerializerSettings.TypeNameHandling = TypeNameHandling.All;
                });

            services.AddControllers(options =>
            {
                options.Filters.Add(typeof(CustomExceptionFilterAttribute));
            });
        }

        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
        public void Configure(IApplicationBuilder gswi, IWebHostEnvironment env, ILoggerFactory loggerFactory)
        {
            gswi.UseForwardedHeaders(new ForwardedHeadersOptions
            {
                ForwardedHeaders = ForwardedHeaders.XForwardedFor | ForwardedHeaders.XForwardedProto
            });

            if (env.IsDevelopment())
            {
                gswi.UseDeveloperExceptionPage();
            }

            NLog.LogManager.LoadConfiguration($"nlog-{env.EnvironmentName}.config");

            gswi.UseCors("CorsPolicy");

            var apiSettings = GetTypedSettingsFromSection<APISettings>("API");
            if (apiSettings.RedirectToHTTPS)
            {
                gswi.UseHttpsRedirection();
            }

            gswi.UseRouting();

            gswi.UseAuthentication();
            gswi.UseAuthorization();

            gswi.UseEndpoints(endpoints =>
            {
                endpoints.MapControllers();
                endpoints.MapHub<NotifyHub>("/notify");
            });
        }

        protected SettingType GetTypedSettingsFromSection<SettingType>(string sectionName) where SettingType : new()
        {
            try
            {
                var settings = new SettingType();
                Configuration.GetSection(sectionName).Bind(settings);
                return settings;
            }
            catch (Exception e)
            {
                _logger.Error(e);
                return new SettingType();
            }
        }
    }
}