using PKISharp.WACS.Configuration;
using PKISharp.WACS.Services;
using System;
using System.IO;
using System.Net;

namespace PKISharp.WACS.Clients
{
    internal class FtpClient
    {
        private NetworkCredential? Credential { get; set; }
        private readonly ILogService _log;

        public FtpClient(NetworkCredentialOptions? options, ILogService log)
        {
            _log = log;
            if (options != null)
            {
                Credential = options.GetCredential();
            }
        }

        private FtpWebRequest CreateRequest(string ftpPath)
        {
            var ftpUri = new Uri(ftpPath);
            var scheme = ftpUri.Scheme;
            if (ftpUri.Scheme == "ftps")
            {
                scheme = "ftp";
            }
            var ftpConnection = scheme + "://" + ftpUri.Host + ":" + ftpUri.Port + ftpUri.AbsolutePath;
            var request = (FtpWebRequest)WebRequest.Create(ftpConnection);
            request.Credentials = Credential;
            if (ftpUri.Scheme == "ftps")
            {
                request.EnableSsl = true;
                request.UsePassive = true;
            }
            return request;
        }

        public void Upload(string ftpPath, string content)
        {
            EnsureDirectories(ftpPath);
            var stream = new MemoryStream();
            using var writer = new StreamWriter(stream);
            writer.Write(content);
            writer.Flush();
            stream.Position = 0;

            var request = CreateRequest(ftpPath);
            request.Method = WebRequestMethods.Ftp.UploadFile;

            using (var requestStream = request.GetRequestStream())
            {
                stream.CopyTo(requestStream);
            }
            using var response = (FtpWebResponse)request.GetResponse();
            _log.Verbose("Upload {ftpPath} status {StatusDescription}", ftpPath, response.StatusDescription?.Trim() ?? "(null)");
        }

        private void EnsureDirectories(string ftpPath)
        {
            var ftpUri = new Uri(ftpPath);
            var directories = ftpUri.AbsolutePath.Split('/');
            var path = ftpUri.Scheme + "://" + ftpUri.Host + ":" + (ftpUri.Port == -1 ? 21 : ftpUri.Port) + "/";
            if (directories.Length > 1)
            {
                for (var i = 1; i < (directories.Length - 1); i++)
                {
                    path = path + directories[i] + "/";
                    var request = CreateRequest(path);
                    request.Method = WebRequestMethods.Ftp.MakeDirectory;
                    try
                    {
                        using var response = (FtpWebResponse)request.GetResponse();
                        _log.Verbose("Create {path} status {StatusDescription}", path, response.StatusDescription?.Trim() ?? "(null)");
                    }
                    catch (Exception ex)
                    {
                        _log.Verbose("Create {path} failed, may already exist ({Message})", path, ex.Message);
                    }
                }
            }
        }

        public string GetFiles(string ftpPath)
        {
            var request = CreateRequest(ftpPath);
            request.Method = WebRequestMethods.Ftp.ListDirectory;
            string names;
            using (var response = (FtpWebResponse)request.GetResponse())
            {
                var responseStream = response.GetResponseStream();
                using var reader = new StreamReader(responseStream);
                names = reader.ReadToEnd();
            }

            names = names.Trim();
            _log.Verbose("Files in path {ftpPath}: {@names}", ftpPath, names);
            return names;
        }

        public void Delete(string ftpPath, FileType fileType)
        {
            var request = CreateRequest(ftpPath);
            if (fileType == FileType.File)
            {
                request.Method = WebRequestMethods.Ftp.DeleteFile;
            }
            else if (fileType == FileType.Directory)
            {
                request.Method = WebRequestMethods.Ftp.RemoveDirectory;
            }
            using var response = (FtpWebResponse)request.GetResponse();
            _log.Verbose("Delete {ftpPath} status {StatusDescription}", ftpPath, response.StatusDescription?.Trim());
        }

        public enum FileType
        {
            File,
            Directory
        }
    }
}