using System;
using System.IO;
using System.Security.Cryptography;
using System.Threading;
using System.Threading.Tasks;
using API.Data;
using API.Entities;
using Kavita.Common;
using Kavita.Common.EnvironmentInfo;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Identity;
using Microsoft.AspNetCore.Server.Kestrel.Core;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using Microsoft.Extensions.Logging;
using Sentry;

namespace API
{
    public class Program
    {
        private static int _httpPort;

        protected Program()
        {
        }

        public static string GetAppSettingFilename()
        {
            var environment = Environment.GetEnvironmentVariable("ASPNETCORE_ENVIRONMENT");
            var isDevelopment = environment == Environments.Development;
            return "appsettings" + (isDevelopment ? ".Development" : "") + ".json";
        }

        public static async Task Main(string[] args)
        {
            Console.OutputEncoding = System.Text.Encoding.UTF8;

            // Before anything, check if JWT has been generated properly or if user still has default
            if (!Configuration.CheckIfJwtTokenSet(GetAppSettingFilename()) && Environment.GetEnvironmentVariable("ASPNETCORE_ENVIRONMENT") != Environments.Development)
            {
                Console.WriteLine("Generating JWT TokenKey for encrypting user sessions...");
                var rBytes = new byte[128];
                using (var crypto = new RNGCryptoServiceProvider()) crypto.GetBytes(rBytes);
                var base64 = Convert.ToBase64String(rBytes).Replace("/", "");
                Configuration.UpdateJwtToken(GetAppSettingFilename(), base64);
            }

            // Get HttpPort from Config
            _httpPort = Configuration.GetPort(GetAppSettingFilename());


            var host = CreateHostBuilder(args).Build();

            using var scope = host.Services.CreateScope();
            var services = scope.ServiceProvider;

            try
            {
                var context = services.GetRequiredService<DataContext>();
                var roleManager = services.GetRequiredService<RoleManager<AppRole>>();
                // Apply all migrations on startup
                await context.Database.MigrateAsync();
                await Seed.SeedRoles(roleManager);
                await Seed.SeedSettings(context);
            }
            catch (Exception ex)
            {
                var logger = services.GetRequiredService <ILogger<Program>>();
                logger.LogError(ex, "An error occurred during migration");
            }

            await host.RunAsync();
        }

        private static IHostBuilder CreateHostBuilder(string[] args) =>
            Host.CreateDefaultBuilder(args)
                .ConfigureWebHostDefaults(webBuilder =>
                {
                    webBuilder.UseKestrel((opts) =>
                    {
                        opts.ListenAnyIP(_httpPort, options =>
                        {
                            options.Protocols = HttpProtocols.Http1AndHttp2;
                        });
                    });

                    var environment = Environment.GetEnvironmentVariable("ASPNETCORE_ENVIRONMENT");
                    if (environment != Environments.Development)
                    {
                        webBuilder.UseSentry(options =>
                        {
                            options.Dsn = "https://40f4e7b49c094172a6f99d61efb2740f@o641015.ingest.sentry.io/5757423";
                            options.MaxBreadcrumbs = 200;
                            options.AttachStacktrace = true;
                            options.Debug = false;
                            options.SendDefaultPii = false;
                            options.DiagnosticLevel = SentryLevel.Debug;
                            options.ShutdownTimeout = TimeSpan.FromSeconds(5);
                            options.Release = BuildInfo.Version.ToString();
                            options.AddExceptionFilterForType<OutOfMemoryException>();
                            options.AddExceptionFilterForType<NetVips.VipsException>();
                            options.AddExceptionFilterForType<InvalidDataException>();
                            options.AddExceptionFilterForType<KavitaException>();

                            options.BeforeSend = sentryEvent =>
                            {
                                if (sentryEvent.Exception != null
                                    && sentryEvent.Exception.Message.StartsWith("[GetCoverImage]")
                                    && sentryEvent.Exception.Message.StartsWith("[BookService]")
                                    && sentryEvent.Exception.Message.StartsWith("[ExtractArchive]")
                                    && sentryEvent.Exception.Message.StartsWith("[GetSummaryInfo]")
                                    && sentryEvent.Exception.Message.StartsWith("[GetSummaryInfo]")
                                    && sentryEvent.Exception.Message.StartsWith("[GetNumberOfPagesFromArchive]")
                                    && sentryEvent.Exception.Message.Contains("EPUB parsing error")
                                    && sentryEvent.Exception.Message.Contains("Unsupported EPUB version")
                                    && sentryEvent.Exception.Message.Contains("Incorrect EPUB")
                                    && sentryEvent.Exception.Message.Contains("Access is Denied"))
                                {
                                    return null; // Don't send this event to Sentry
                                }

                                sentryEvent.ServerName = null; // Never send Server Name to Sentry
                                return sentryEvent;
                            };

                            options.ConfigureScope(scope =>
                            {
                                scope.User = new User()
                                {
                                    Id = HashUtil.AnonymousToken()
                                };
                                scope.Contexts.App.Name = BuildInfo.AppName;
                                scope.Contexts.App.Version = BuildInfo.Version.ToString();
                                scope.Contexts.App.StartTime = DateTime.UtcNow;
                                scope.Contexts.App.Hash = HashUtil.AnonymousToken();
                                scope.Contexts.App.Build = BuildInfo.Release;
                                scope.SetTag("culture", Thread.CurrentThread.CurrentCulture.Name);
                                scope.SetTag("branch", BuildInfo.Branch);
                            });

                        });
                    }

                    webBuilder.UseStartup<Startup>();
                });
    }
}