using DbUp;
using Newtonsoft.Json;
using System;
using System.Collections.Generic;
using System.Data.SqlClient;
using System.Net.Http;
using System.Reflection;
using System.IO;

namespace Bit.Setup
{
    public class Program
    {
        private static string[] _args = null;
        private static IDictionary<string, string> _parameters = null;
        private static Guid? _installationId = null;
        private static string _installationKey = null;
        private static string _hostOs = "win";
        private static string _coreVersion = "latest";
        private static string _webVersion = "latest";

        public static void Main(string[] args)
        {
            _args = args;
            _parameters = ParseParameters();
            if(_parameters.ContainsKey("os"))
            {
                _hostOs = _parameters["os"];
            }
            if(_parameters.ContainsKey("corev"))
            {
                _coreVersion = _parameters["corev"];
            }
            if(_parameters.ContainsKey("webv"))
            {
                _webVersion = _parameters["webv"];
            }

            if(_parameters.ContainsKey("install"))
            {
                Install();
            }
            else if(_parameters.ContainsKey("update"))
            {
                Update();
            }
            else if(_parameters.ContainsKey("printenv"))
            {
                PrintEnvironment();
            }
            else
            {
                Console.WriteLine("No top-level command detected. Exiting...");
            }
        }

        private static void Install()
        {
            var outputDir = _parameters.ContainsKey("out") ?
                _parameters["out"].ToLowerInvariant() : "/etc/bitwarden";
            var domain = _parameters.ContainsKey("domain") ?
                _parameters["domain"].ToLowerInvariant() : "localhost";
            var letsEncrypt = _parameters.ContainsKey("letsencrypt") ?
                _parameters["letsencrypt"].ToLowerInvariant() == "y" : false;

            if(!ValidateInstallation())
            {
                return;
            }

            var ssl = letsEncrypt;
            if(!letsEncrypt)
            {
                Console.Write("(!) Do you have a SSL certificate to use? (y/n): ");
                ssl = Console.ReadLine().ToLowerInvariant() == "y";

                if(ssl)
                {
                    Directory.CreateDirectory($"/bitwarden/ssl/{domain}/");
                    Console.WriteLine("Make sure 'certificate.crt' and 'private.key' are provided in the " +
                        "appropriate directory (see docs for info).");
                }
            }

            var identityCertPassword = Helpers.SecureRandomString(32, alpha: true, numeric: true);
            var certBuilder = new CertBuilder(domain, identityCertPassword, letsEncrypt, ssl);
            var selfSignedSsl = certBuilder.BuildForInstall();
            ssl = certBuilder.Ssl; // Ssl prop can get flipped during the build

            var url = ssl ? $"https://{domain}" : $"http://{domain}";
            Console.Write("(!) Do you want to use the default ports for HTTP (80) and HTTPS (443)? (y/n): ");
            var defaultPorts = Console.ReadLine().ToLowerInvariant() == "y";
            int httpPort = default(int), httpsPort = default(int);
            if(!defaultPorts)
            {
                Console.Write("(!) HTTP port: ");
                if(int.TryParse(Console.ReadLine().ToLowerInvariant().Trim(), out httpPort))
                {
                    if(ssl)
                    {
                        Console.Write("(!) HTTPS port: ");
                        if(int.TryParse(Console.ReadLine().ToLowerInvariant().Trim(), out httpsPort))
                        {
                            if(httpsPort != 443)
                            {
                                url += (":" + httpsPort);
                            }
                        }
                        else
                        {
                            Console.WriteLine("Invalid HTTPS port.");
                            httpPort = httpsPort = default(int);
                        }
                    }
                    else if(httpPort != 80)
                    {
                        url += (":" + httpPort);
                    }
                }
                else
                {
                    Console.WriteLine("Invalid HTTP port.");
                }
            }

            Console.Write("(!) Is your installation behind a reverse proxy? (y/n): ");
            var reverseProxy = Console.ReadLine().ToLowerInvariant() == "y";
            if(reverseProxy)
            {
                Console.Write("(!) Do you use the default ports on your reverse proxy (80/443)? (y/n): ");
                var proxyDefaultPorts = Console.ReadLine().ToLowerInvariant() == "y";

                if(proxyDefaultPorts)
                {
                    url = ssl ? $"https://{domain}" : $"http://{domain}";
                }
                else
                {
                    int httpReversePort = default(int), httpsReversePort = default(int);
                    Console.Write("(!) Proxy HTTP port: ");
                    if(int.TryParse(Console.ReadLine().ToLowerInvariant().Trim(), out httpReversePort))
                    {
                        if(ssl)
                        {
                            Console.Write("(!) Proxy HTTPS port: ");
                            if(int.TryParse(Console.ReadLine().ToLowerInvariant().Trim(), out httpsReversePort))
                            {
                                if(httpsReversePort != 443)
                                {
                                    url += (":" + httpsReversePort);
                                }
                            }
                            else
                            {
                                Console.WriteLine("Invalid proxy HTTPS port.");
                                httpReversePort = httpsReversePort = default(int);
                            }
                        }
                        else if(httpReversePort != 80)
                        {
                            url += (":" + httpReversePort);
                        }
                    }
                    else
                    {
                        Console.WriteLine("Invalid proxy HTTP port.");
                    }
                }
            }

            Console.Write("(!) Do you want to use push notifications? (y/n): ");
            var push = Console.ReadLine().ToLowerInvariant() == "y";

            var nginxBuilder = new NginxConfigBuilder(domain, url, ssl, selfSignedSsl, letsEncrypt);
            nginxBuilder.BuildForInstaller();

            var environmentFileBuilder = new EnvironmentFileBuilder
            {
                DatabasePassword = Helpers.SecureRandomString(32),
                Domain = domain,
                IdentityCertPassword = identityCertPassword,
                InstallationId = _installationId,
                InstallationKey = _installationKey,
                OutputDirectory = outputDir,
                Push = push,
                Url = url
            };
            environmentFileBuilder.BuildForInstaller();

            var appSettingsBuilder = new AppSettingsBuilder();
            appSettingsBuilder.Build();

            var appIdBuilder = new AppIdBuilder(url);
            appIdBuilder.Build();

            var dockerComposeBuilder = new DockerComposeBuilder(_hostOs, _webVersion, _coreVersion);
            dockerComposeBuilder.BuildForInstaller(httpPort, httpsPort);
        }

        private static void Update()
        {
            if(_parameters.ContainsKey("db"))
            {
                MigrateDatabase();
            }
            else
            {
                RebuildConfigs();
            }
        }

        private static void PrintEnvironment()
        {
            var vaultUrl = Helpers.GetValueFronEnvFile("global", "globalSettings__baseServiceUri__vault");
            Console.WriteLine("\nBitwarden is up and running!");
            Console.WriteLine("===================================================");
            Console.WriteLine("\nvisit {0}", vaultUrl);
            Console.Write("to update, run ");
            if(_hostOs == "win")
            {
                Console.Write("'.\\bitwarden.ps1 -updateself' and then '.\\bitwarden.ps1 -update'");
            }
            else
            {
                Console.Write("'./bitwarden.sh updateself' and then './bitwarden.sh update'");
            }
            Console.WriteLine("\n");
        }

        private static void MigrateDatabase(int attempt = 1)
        {
            try
            {
                Console.WriteLine("Migrating database.");

                var dbPass = Helpers.GetValueFronEnvFile("mssql", "SA_PASSWORD");
                var masterConnectionString = Helpers.MakeSqlConnectionString(
                    "mssql", "master", "sa", dbPass ?? string.Empty);
                var vaultConnectionString = Helpers.MakeSqlConnectionString(
                    "mssql", "vault", "sa", dbPass ?? string.Empty);

                using(var connection = new SqlConnection(masterConnectionString))
                {
                    var command = new SqlCommand(
                        "IF ((SELECT COUNT(1) FROM sys.databases WHERE [name] = 'vault') = 0) " +
                        "CREATE DATABASE [vault];", connection);
                    command.Connection.Open();
                    command.ExecuteNonQuery();
                }

                var upgrader = DeployChanges.To
                    .SqlDatabase(vaultConnectionString)
                    .JournalToSqlTable("dbo", "Migration")
                    .WithScriptsAndCodeEmbeddedInAssembly(Assembly.GetExecutingAssembly(),
                        s => s.Contains($".DbScripts.") && !s.Contains(".Archive."))
                    .WithTransaction()
                    .WithExecutionTimeout(new TimeSpan(0, 5, 0))
                    .LogToConsole()
                    .Build();

                var result = upgrader.PerformUpgrade();
                if(result.Successful)
                {
                    Console.WriteLine("Migration successful.");
                }
                else
                {
                    Console.WriteLine("Migration failed.");
                }
            }
            catch(SqlException e)
            {
                if(e.Message.Contains("Server is in script upgrade mode") && attempt < 3)
                {
                    var nextAttempt = attempt + 1;
                    Console.WriteLine("Database is in script upgrade mode. " +
                        "Trying again (attempt #{0})...", nextAttempt);
                    MigrateDatabase(nextAttempt);
                    return;
                }

                throw e;
            }
        }

        private static bool ValidateInstallation()
        {
            Console.Write("(!) Enter your installation id (get it at https://bitwarden.com/host): ");
            var installationId = Console.ReadLine();
            Guid installationidGuid;
            if(!Guid.TryParse(installationId.Trim(), out installationidGuid))
            {
                Console.WriteLine("Invalid installation id.");
                return false;
            }
            _installationId = installationidGuid;

            Console.Write("(!) Enter your installation key: ");
            _installationKey = Console.ReadLine();

            try
            {
                var response = new HttpClient().GetAsync("https://api.bitwarden.com/installations/" + _installationId)
                    .GetAwaiter().GetResult();

                if(!response.IsSuccessStatusCode)
                {
                    if(response.StatusCode == System.Net.HttpStatusCode.NotFound)
                    {
                        Console.WriteLine("Invalid installation id.");
                    }
                    else
                    {
                        Console.WriteLine("Unable to validate installation id.");
                    }

                    return false;
                }

                var resultString = response.Content.ReadAsStringAsync().GetAwaiter().GetResult();
                var result = JsonConvert.DeserializeObject<dynamic>(resultString);
                if(!(bool)result.Enabled)
                {
                    Console.WriteLine("Installation id has been disabled.");
                    return false;
                }

                return true;
            }
            catch
            {
                Console.WriteLine("Unable to validate installation id. Problem contacting Bitwarden server.");
                return false;
            }
        }

        private static void RebuildConfigs()
        {
            var environmentFileBuilder = new EnvironmentFileBuilder();
            environmentFileBuilder.BuildForUpdater();

            var url = Helpers.GetValueFronEnvFile("global", "globalSettings__baseServiceUri__vault");
            if(!Uri.TryCreate(url, UriKind.Absolute, out Uri uri))
            {
                Console.WriteLine("Unable to determine existing installation url.");
                return;
            }

            var domain = uri.Host;

            var nginxBuilder = new NginxConfigBuilder(domain, url);
            nginxBuilder.BuildForUpdater();

            var appSettingsBuilder = new AppSettingsBuilder();
            appSettingsBuilder.Build();

            var appIdBuilder = new AppIdBuilder(url);
            appIdBuilder.Build();

            var dockerComposeBuilder = new DockerComposeBuilder(_hostOs, _webVersion, _coreVersion);
            dockerComposeBuilder.BuildForUpdater();
        }

        private static IDictionary<string, string> ParseParameters()
        {
            var dict = new Dictionary<string, string>();
            for(var i = 0; i < _args.Length; i = i + 2)
            {
                if(!_args[i].StartsWith("-"))
                {
                    continue;
                }

                dict.Add(_args[i].Substring(1), _args[i + 1]);
            }

            return dict;
        }
    }
}