using System;
using System.Linq;
using System.ServiceModel;
using System.Threading.Tasks;
using Alkami.Ops.SecretServer.Enum;
using Alkami.Ops.SecretServer.Messages;
using Alkami.Ops.SecretServer.Model;
using Alkami.Ops.SecretServer.SSWebService;

namespace Alkami.Ops.SecretServer
{
    /// <summary>
    /// A simple client for secret server
    /// </summary>
    public sealed class Client : IDisposable
    {
        private string _authenticationToken;

        private readonly SSWebServiceSoapClient _client;

        /// <summary>
        /// Gets all secrets from a folder based on folder name
        /// </summary>
        /// <param name="folderName"></param>
        /// <returns></returns>
        public async Task<SecretSearchResult> GetFolderSecretsAsync(string folderName)
        {
            try
            {
                Console.WriteLine($"Attempting to find all secrets in folder: {folderName}");
                var folderSearchResult = await FindFolderAsync(folderName);

                if (folderSearchResult.Status == ResultStatus.Success)
                {
                    Console.WriteLine($"Attempting to get all secrets from folder with name: {folderName} and folder ID: {folderSearchResult.Folders.First().Id}");
                    return await GetAllSecretsFromFolderAsync(folderSearchResult.Folders.First());
                }

                Console.WriteLine($"Attempt to find folder {folderName} resulted in errors: {string.Join(",", folderSearchResult.Errors)}");
                return new SecretSearchResult
                {
                    Errors = folderSearchResult.Errors,
                    Message = folderSearchResult.Message
                };
            }
            catch (Exception e)
            {
                Console.WriteLine($"An error occurred while attempting to get all secrets from folder with name: {folderName}.  Exception: {e}");
                throw;
            }
        }

        /// <summary>
        /// Authenticates using the supplied username, password, and domain
        /// </summary>
        /// <param name="userName"></param>
        /// <param name="password"></param>
        /// <param name="domain"></param>
        /// <returns></returns>
        public async Task<AuthenticationResult> AuthenticateAsync(string userName, string password, string domain)
        {
            try
            {
                Console.WriteLine($"Attempting authentication with username: {userName} and domain {domain}");
                var result = await _client.AuthenticateAsync(userName, password, string.Empty, domain);

                Console.WriteLine(result.Errors != null && result.Errors.Any()
                                      ? $"Encountered errors during authentication: {string.Join(",", result.Errors)}"
                                      : "Authentication successful");

                return new AuthenticationResult
                {
                    Status = (result.Errors != null && result.Errors.Any() ? ResultStatus.Failure : ResultStatus.Success),
                    Message = (result.Errors != null && result.Errors.Any() ? "Authentication Failed" : "Authentication Successful"),
                    Errors = result.Errors?.Select(e => new ResultError(null, e)).ToList(),
                    Token = _authenticationToken = result.Token
                };
            }
            catch (Exception e)
            {
                Console.WriteLine($"An error occurred while attempting to authentice with username: {userName} and domain {domain}.  Exception: {e}");
                throw;
            }
        }

        /// <summary>
        /// Returns a collection of secrets from a folder as a <see cref="SecretSearchResult"/>
        /// </summary>
        /// <param name="folder"></param>
        /// <returns></returns>
        private async Task<SecretSearchResult> GetAllSecretsFromFolderAsync(Folder folder)
        {
            try
            {
                Console.WriteLine($"Attempting to pull all secrets from folder {folder.Name}");
                var folderSearchResponse = await _client.SearchSecretsByFolderAsync(_authenticationToken, "*", folder.Id, false, false, true);
                var results = new SecretSearchResult();

                if (folderSearchResponse.SearchSecretsByFolderResult.Errors != null && folderSearchResponse.SearchSecretsByFolderResult.Errors.Any())
                {
                    Console.WriteLine($"Attempt to pull secrets from folder {folder.Name} resulted in errors: {string.Join(",", folderSearchResponse.SearchSecretsByFolderResult.Errors)}");
                    results.Errors = folderSearchResponse.SearchSecretsByFolderResult.Errors.Select(e => new ResultError(null, e)).ToList();
                    results.Status = ResultStatus.Failure;
                }

                foreach (var secretSummary in folderSearchResponse.SearchSecretsByFolderResult.SecretSummaries)
                {
                    Console.WriteLine($"Getting secret details for secret ID: {secretSummary.SecretId} with name: {secretSummary.SecretName}");
                    var secretResponse = await _client.GetSecretAsync(_authenticationToken, secretSummary.SecretId, false, null);

                    if (secretResponse.GetSecretResult.Errors.Any())
                    {
                        Console.WriteLine($"Attempt to pull secrets from folder {folder.Name} resulted in errors: {string.Join(",", secretResponse.GetSecretResult.Errors)}");
                        results.Errors.Add(new ResultError(secretSummary.SecretId,
                                                           $"Error {secretResponse.GetSecretResult.Errors[0]} occurred while getting secret {secretSummary.SecretId}"));
                        results.Status = ResultStatus.PartialFailure;
                        continue;
                    }

                    switch (secretSummary.SecretTypeName.ToUpperInvariant())
                    {
                        case "SSL CERTIFICATE":
                        case "CERTIFICATE":
                        {
                            Console.WriteLine($"Secret with ID {secretSummary.SecretId} determined to be of type Certificate");
                            var certificate = new Certificate(secretResponse.GetSecretResult.Secret);

                            if (!certificate.FileId.HasValue)
                            {
                                Console.WriteLine($"Certificate with secret ID {secretSummary.SecretId} does not have an attachment");
                                results.Errors.Add(new ResultError(secretSummary.SecretId,
                                                                   $"Unable to find a certificate attachemnt for secret {certificate.Id}"));
                                continue;
                            }

                            // Download the PFX Files
                            Console.WriteLine($"Attempting to download attachment for Certificate with secret ID {secretSummary.SecretId}");
                            var certificateAttachment = await DownloadFileAsync(certificate.Id, certificate.FileId.Value);

                            certificate.FileAttachment = certificateAttachment.FileAttachment;

                            certificate.FileName = certificateAttachment.FileName;
                            results.Secrets.Add(secretResponse.GetSecretResult.Secret.Id, certificate);
                            break;
                        }
                        case "WINDOWS ACCOUNT":
                        {
                            Console.WriteLine($"Secret with ID {secretSummary.SecretId} determined to be of type User");
                            results.Secrets.Add(secretResponse.GetSecretResult.Secret.Id, new Model.User(secretResponse.GetSecretResult.Secret));
                            break;
                        }
                        case "SQL SERVER ACCOUNT":
                        {
                            Console.WriteLine($"Secret with ID {secretSummary.SecretId} determined to be of type ConnectionString");
                            results.Secrets.Add(secretResponse.GetSecretResult.Secret.Id, new ConnectionString(secretResponse.GetSecretResult.Secret));
                            break;
                        }
                        default:
                        {
                            Console.WriteLine($"Secret with ID {secretSummary.SecretId} is an unmapped type");
                            results.Errors.Add(new ResultError(secretSummary.SecretId,
                                                               $"Unknown secret type {secretSummary.SecretTypeName} found for secret ID {secretSummary.SecretId}"));
                            results.Status = ResultStatus.PartialFailure;
                            break;
                        }
                    }
                }

                if (!results.Secrets.Any())
                {
                    // All secret searches failed
                    results.Status = ResultStatus.Failure;
                }
                else if (results.Status == ResultStatus.Unknown)
                {
                    // All secret searches passed, otherwise this would be PartialFailure
                    results.Status = ResultStatus.Success;
                }

                return results;
            }
            catch (Exception e)
            {
                Console.WriteLine($"An error occurred while attempting to pull all secrets from folder {folder.Name}.  Exception: {e}");
                throw;
            }
        }

        /// <summary>
        /// Downloads a file based on the parent Secret and File ItemId
        /// </summary>
        /// <param name="secretId"></param>
        /// <param name="fileItemId"></param>
        /// <returns></returns>
        private async Task<Messages.FileDownloadResult> DownloadFileAsync(int secretId, int fileItemId)
        {
            try
            {
                Console.WriteLine($"Attempting to download file attachment for secret with ID: {secretId} and fileItemID: {fileItemId}");
                var downloadResponse = await _client.DownloadFileAttachmentByItemIdAsync(_authenticationToken, secretId, fileItemId);
                var result = new Messages.FileDownloadResult();

                if (downloadResponse.Errors.Any() || downloadResponse.FileAttachment.Length == 0)
                {
                    Console.WriteLine($"Attempt to download attachment from secret with ID {secretId} resulted in errors: {string.Join(",", downloadResponse.Errors)}");
                    result.Status = ResultStatus.Failure;
                    result.Errors = downloadResponse.Errors.Select(e => new ResultError(secretId, e)).ToList();
                }
                else
                {
                    result.Status = ResultStatus.Success;
                    result.FileAttachment = downloadResponse.FileAttachment;
                    result.FileName = downloadResponse.FileName;
                }

                return result;
            }
            catch (Exception e)
            {
                Console.WriteLine($"An error occurred while attempting to download file attachment for secret with ID: {secretId} and fileItemID: {fileItemId}.  Exception: {e}");
                throw;
            }
        }

        /// <summary>
        /// Finds a Secret Folder based on FolderName
        /// </summary>
        /// <param name="folderName"></param>
        /// <returns></returns>
        private async Task<FolderSearchResult> FindFolderAsync(string folderName)
        {
            try
            {
                Console.WriteLine($"Attempting to find folder with name: {folderName}");
                var folderResponse = await _client.SearchFoldersAsync(_authenticationToken, folderName);

                if (!folderResponse.Errors.Any() && folderResponse.Folders.Count() == 1)
                {
                    return new FolderSearchResult
                    {
                        Status = ResultStatus.Success,
                        Folders = folderResponse.Folders
                    };
                }

                if (folderResponse.Errors.Any())
                {
                    Console.WriteLine($"Attempt to find folder with name {folderName} resulted in errors: {string.Join(",", folderResponse.Errors)}");
                }
                else if (folderResponse.Folders.Count() > 1)
                {
                    Console.WriteLine("More than one folder was returned -- narrow your search and/or check the secret folder configuration.");
                }

                return new FolderSearchResult
                {
                    Errors = folderResponse.Errors.Select(e => new ResultError(null, e)).ToList(),
                    Status = ResultStatus.Failure,
                    Message = $"Folder Search for {folderName} Failed"
                };
            }
            catch (Exception e)
            {
                Console.WriteLine($"An error occurred while attempting to find folder with name: {folderName}.  Exception: {e}");
                throw;
            }
        }

        /// <summary>
        /// Instantiates a new instance of the Client class
        /// </summary>
        public Client()
        {
            const string endpointAddress = "https://secret.corp.alkamitech.com/webservices/SSWebService.asmx";
            var binding = new BasicHttpBinding
            {
                Name = "SSWebServiceSoap",
                Security =
                {
                    Mode = BasicHttpSecurityMode.Transport
                }
            };

            var endpoint = new EndpointAddress(endpointAddress);
            _client = new SSWebServiceSoapClient(binding, endpoint);
        }

        #region Implement IDisposable

        /// <summary>
        /// Implementation of IDisposable.
        /// </summary>
        /// <remarks>
        /// Calls Dispose on the <see cref="SSWebServiceSoapClient"/>
        /// </remarks>
        public void Dispose()
        {
            ((IDisposable)_client)?.Dispose();
        }

        #endregion Implement IDisposable
    }
}