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

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;

        public static void Main(string[] args)
        {
            _args = args;
            _parameters = ParseParameters();
            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)
                {
                    Console.WriteLine("Make sure 'certificate.crt' and 'private.key' are provided in the " +
                        "appropriate directory (see setup instructions).");
                }
            }

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

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

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

            var appSettingsBuilder = new AppSettingsBuilder(url, domain);
            appSettingsBuilder.Build();

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

        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("\n- visit {0}", vaultUrl);
            Console.Write("- to update, run ");
            if(_parameters.ContainsKey("env") && _parameters["env"] == "win")
            {
                Console.Write("'.\\bitwarden.ps1 -update'");
            }
            else
            {
                Console.Write("'./bitwarden.sh update'");
            }
            Console.WriteLine("\n");
        }

        private static void MigrateDatabase()
        {
            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.");
            }
        }

        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 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);
            nginxBuilder.UpdateContext();
            nginxBuilder.BuildForUpdater();

            var appSettingsBuilder = new AppSettingsBuilder(url, domain);
            appSettingsBuilder.Build();

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

        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;
        }
    }
}