using Core;
using ICSharpCode.SharpZipLib.Core;
using ICSharpCode.SharpZipLib.Zip;
using LiMan.APi.Data;
using LiMan.DB.DBModels;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.StaticFiles;
using Microsoft.Extensions.Configuration;
using NLog;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Net;
using System.Threading.Tasks;

namespace LiMan.APi.Controllers
{
    /// <summary>
    /// Controller caricamento file
    /// </summary>
    [ApiController]
    [Route("api/filesave")]
    public class FilesaveController : ControllerBase
    {
        #region Public Constructors

        /// <summary>
        /// Init generico
        /// </summary>
        /// <param name="configuration"></param>
        /// <param name="DataService"></param>
        /// <param name="env"></param>
        public FilesaveController(IConfiguration configuration, ApiDataService DataService, IWebHostEnvironment env)
        {
            dataService = DataService;
            _configuration = configuration;
            this.env = env;
            Log.Info("Avviata classe FilesaveController");
        }

        #endregion Public Constructors

        #region Public Methods

        /// GET api/filesave/id/filename
        /// <summary>
        /// Recupera un singolo file dato ticket code + nome file (safe)
        /// </summary>
        /// <param name="id">Ticket code formato T00000000</param>
        /// <param name="secureName">Nome file (safe)</param>
        /// <param name="fileName">Nome file da scaricare</param>
        /// <returns></returns>
        [HttpGet("{id}/{secureName}/{fileName}")]
        public async Task<ActionResult> DownloadFile(string id, string secureName, string fileName)
        {
            string relDir = _configuration["ServerConf:FileShareTickets"];
            string ticketDir = Path.Combine(relDir, id);
            var filePath = Path.Combine(ticketDir, secureName);
            // verifico esistenza..
            if (System.IO.File.Exists(filePath))
            {
                var bytes = await System.IO.File.ReadAllBytesAsync(filePath);
                return File(bytes, GetMimeType(fileName), fileName);
            }
            else
            {
                return File(new byte[0], "text/plain", "Empty.txt");
            }
        }

        /// <summary>
        /// Elenco files associati a ticket supporto POST api/filesave/list/1
        /// </summary>
        /// <param name="id"></param>
        /// <param name="CurrRequest"></param>
        /// <returns></returns>
        [HttpPost("list/{id}")]
        public async Task<List<FileAttachModel>> list(int id, [FromBody] SupportRequest CurrRequest)
        {
            List<FileAttachModel> result = new List<FileAttachModel>();
            // controllo valori
            if (CurrRequest.IsValid)
            {
                // cerco i files dato ticket
                result = await dataService.FileGetFilt(id);
                await dataService.recordCall(CurrRequest.CodInst, CurrRequest.CodApp, $"POST:api/files/list:{id}");
            }
            return result;
        }

        /// <summary>
        /// Caricamento file effettivo via POST
        /// </summary>
        /// <param name="ticketId">TicketId x riferimento</param>
        /// <param name="files">Elenco files da caricare</param>
        /// <returns></returns>
        [HttpPost()]
        public async Task<ActionResult<IList<UploadResult>>> PostFiles([FromForm] int ticketId, [FromForm] IEnumerable<IFormFile> files)
        {
            // max 10 files
            var maxAllowedFiles = 10;
            // max 50 mb
            long maxFileSize = 1024 * 1024 * 50;
            var filesProcessed = 0;
            string ticketDir = $"T{ticketId:000000000}";
            var resourcePath = new Uri($"{Request.Scheme}://{Request.Host}/api/filesave/list/{ticketId}");
            List<UploadResult> uploadResults = new();
            string fileDir = env.ContentRootPath;
            string relDir = env.EnvironmentName;

            foreach (var file in files)
            {
                var uploadResult = new UploadResult();
                string trustedFileNameForFileStorage;
                var untrustedFileName = file.FileName;
                uploadResult.FileName = untrustedFileName;
                var trustedFileNameForDisplay = WebUtility.HtmlEncode(untrustedFileName);

                if (filesProcessed < maxAllowedFiles)
                {
                    if (file.Length == 0)
                    {
                        Log.Info($"{trustedFileNameForDisplay} length is 0 (Err: 1)");
                        uploadResult.ErrorCode = 1;
                    }
                    else if (file.Length > maxFileSize)
                    {
                        Log.Info($"{trustedFileNameForDisplay} of {CalcSize(file.Length)} is larger than the limit of {CalcSize(maxFileSize)} (Err: 2)");
                        uploadResult.ErrorCode = 2;
                    }
                    else
                    {
                        try
                        {
                            DateTime oggi = DateTime.Today;
                            trustedFileNameForFileStorage = Path.GetRandomFileName();
                            relDir = _configuration["ServerConf:FileShareTickets"];
                            fileDir = Path.Combine(relDir, ticketDir);
                            if (!Directory.Exists(fileDir))
                            {
                                Directory.CreateDirectory(fileDir);
                            }
                            var path = Path.Combine(fileDir, trustedFileNameForFileStorage);

                            await using FileStream fs = new(path, FileMode.Create);
                            await file.CopyToAsync(fs);

                            Log.Info($"{trustedFileNameForDisplay} saved at {path}");
                            uploadResult.Uploaded = true;
                            uploadResult.StoredFileName = trustedFileNameForFileStorage;
                        }
                        catch (IOException ex)
                        {
                            Log.Error($"{trustedFileNameForDisplay} error on upload (Err: 3): {ex.Message}");
                            uploadResult.ErrorCode = 3;
                        }
                    }

                    filesProcessed++;
                }
                else
                {
                    Log.Info($"{trustedFileNameForDisplay} not uploaded because the request exceeded the allowed {maxAllowedFiles} of files (Err: 4)");
                    uploadResult.ErrorCode = 4;
                }

                uploadResults.Add(uploadResult);
            }
            // salvo su DB
            var fatto = dataService.FileAdd(ticketId, ticketDir, uploadResults);
            Log.Info($"Ticket: {ticketId} | dir: {ticketDir} | {uploadResults.Count} files");

            return new CreatedResult(resourcePath, uploadResults);
        }

        /// <summary>
        /// Caricamento file effettivo via POST
        /// </summary>
        /// <param name="ticketId">TicketId x riferimento</param>
        /// <param name="file">Elenco files da caricare</param>
        /// <returns></returns>
        [HttpPost("single")]
        public async Task<ActionResult<UploadResult>> PostSingleFile([FromForm] int ticketId, [FromForm] IFormFile file)
        {
            // max 200 mb
            long maxFileSize = 1024 * 1024 * 200;
            string ticketDir = $"T{ticketId:000000000}";
            var resourcePath = new Uri($"{Request.Scheme}://{Request.Host}/api/filesave/list/{ticketId}");
            List<UploadResult> uploadResults = new();
            string fileDir = env.ContentRootPath;
            string relDir = env.EnvironmentName;

            var uploadResult = new UploadResult();
            string trustedFileNameForFileStorage;
            var untrustedFileName = file.FileName;
            uploadResult.FileName = untrustedFileName;
            var trustedFileNameForDisplay = WebUtility.HtmlEncode(untrustedFileName);

            if (file.Length == 0)
            {
                Log.Info($"{trustedFileNameForDisplay} length is 0 (Err: 1)");
                uploadResult.ErrorCode = 1;
            }
            else if (file.Length > maxFileSize)
            {
                Log.Info($"{trustedFileNameForDisplay} of {CalcSize(file.Length)} is larger than the limit of {CalcSize(maxFileSize)} (Err: 2)");
                uploadResult.ErrorCode = 2;
            }
            else
            {
                try
                {
                    DateTime oggi = DateTime.Today;
                    trustedFileNameForFileStorage = Path.GetRandomFileName();
                    relDir = _configuration["ServerConf:FileShareTickets"];
                    fileDir = Path.Combine(relDir, ticketDir);
                    if (!Directory.Exists(fileDir))
                    {
                        Directory.CreateDirectory(fileDir);
                    }
                    var path = Path.Combine(fileDir, trustedFileNameForFileStorage);

                    await using FileStream fs = new(path, FileMode.Create);
                    await file.CopyToAsync(fs);

                    Log.Info($"{trustedFileNameForDisplay} saved at {path}");
                    uploadResult.Uploaded = true;
                    uploadResult.StoredFileName = trustedFileNameForFileStorage;
                }
                catch (IOException ex)
                {
                    Log.Error($"{trustedFileNameForDisplay} error on upload (Err: 3): {ex.Message}");
                    uploadResult.ErrorCode = 3;
                }
            }

            uploadResults.Add(uploadResult);
            // salvo su DB
            var fatto = dataService.FileAdd(ticketId, ticketDir, uploadResults);
            Log.Info($"Ticket: {ticketId} | dir: {ticketDir} | {uploadResults.Count} files");

            return new CreatedResult(resourcePath, uploadResult);
        }

        /// <summary>
        /// Caricamento file backup applicativo in formato ZIP via FORM POST (backup configurazione applicativo, file protetto da masterKey)
        /// </summary>
        /// <param name="CodApp">Applicazione di riferimento</param>
        /// <param name="CodInst">Installazione di riferimento</param>
        /// <param name="DoUnzip">Richiesta UnZip file post caricamento</param>
        /// <param name="ForceApprov">
        /// Richiesta di approvazione salvataggio files modificati post upload + unzip
        /// </param>
        /// <param name="ZipFile">File da caricare ed estrarre</param>
        /// <returns></returns>
        [HttpPost("zipbackup")]
        public async Task<ActionResult<UploadResult>> PostZipFile([FromForm] string CodApp, [FromForm] string CodInst, [FromForm] bool DoUnzip, [FromForm] bool ForceApprov, [FromForm] IFormFile ZipFile)
        {
            // max 200 mb
            long maxFileSize = 1024 * 1024 * 200;
            // preparo oggetti x risposta
            var resourcePath = new Uri($"{Request.Scheme}://{Request.Host}/api/filesave/");
            List<UploadResult> uploadResults = new List<UploadResult>();
            string fileDir = env.ContentRootPath;
            string relDir = env.EnvironmentName;
            string authKey = "";
            var uploadResult = new UploadResult();
            uploadResult.FileName = ZipFile.FileName;
            // controllo size e procedo
            if (ZipFile.Length == 0)
            {
                Log.Info($"{ZipFile.FileName} length is 0 (Err: 1)");
                uploadResult.ErrorCode = 1;
            }
            else if (ZipFile.Length > maxFileSize)
            {
                Log.Info($"{ZipFile.FileName} of {CalcSize(ZipFile.Length)} is larger than the limit of {CalcSize(maxFileSize)} (Err: 2)");
                uploadResult.ErrorCode = 2;
            }
            else
            {
                try
                {
                    DateTime oggi = DateTime.Today;
                    relDir = _configuration["ServerConf:FileShareAppBackup"];
                    fileDir = Path.Combine(relDir, CodApp, CodInst);
                    if (!Directory.Exists(fileDir))
                    {
                        Directory.CreateDirectory(fileDir);
                    }
                    var filePath = Path.Combine(fileDir, ZipFile.FileName);

                    // elimino se ci fosse già il file...
                    if (System.IO.File.Exists(filePath))
                    {
                        System.IO.File.Delete(filePath);
                    }

                    // salvo da filestream a file locale
                    using (FileStream fs = new(filePath, FileMode.Create))
                    {
                        await ZipFile.CopyToAsync(fs);
                    }

                    // log!
                    Log.Info($"{ZipFile.FileName} saved at {filePath}");
                    uploadResult.Uploaded = true;
                    uploadResult.StoredFileName = ZipFile.FileName;
                    // se richiesto unzip eseguo
                    if (DoUnzip)
                    {
                        bool extractDone = false;
                        // recupero applicativi connessi
                        var listLic = await dataService.AppDtoSearch(CodInst, CodApp, false);
                        var currLic = listLic.Where(x => x.IsActive).FirstOrDefault();
                        // procedo SOLO SE ho una licenza attiva x questo cliente
                        if (currLic != null)
                        {
                            //recupero authKey
                            authKey = currLic.Chiave;
                            using (ZipFile zf = new ZipFile(filePath))
                            {
                                zf.Password = authKey;
                                foreach (ZipEntry zipEntry in zf)
                                {
                                    // Manipulate the output filename here as desired.
                                    var entryFileName = zipEntry.Name;
                                    var fullZipToPath = Path.Combine(fileDir, entryFileName);
                                    Console.WriteLine(zipEntry.Name);
                                    if (!zipEntry.IsFile)
                                    {
                                        Directory.CreateDirectory(fullZipToPath);
                                        // Ignore directories
                                        continue;
                                    }

                                    // 4K is optimum
                                    var buffer = new byte[4096];

                                    // Unzip file in buffered chunks. This is just as fast as
                                    // unpacking to a buffer the full size of the file, but does not
                                    // waste memory. The "using" will close the stream even if an
                                    // exception occurs.
                                    using (var zipStream = zf.GetInputStream(zipEntry))
                                    {
                                        using (Stream fsOutput = System.IO.File.Create(fullZipToPath))
                                        {
                                            StreamUtils.Copy(zipStream, fsOutput, buffer);
                                        }
                                    }
                                    extractDone = true;
                                }
                            }
                            // elimino zip e altro...
                            if (extractDone)
                            {
                                System.IO.File.Delete(filePath);
                            }

                            // se richiesta auto approvazione eseguo...
                            string reqAppFile = Path.Combine(fileDir, "ChangeApprove.req");
                            if (System.IO.File.Exists(reqAppFile))
                            {
                                System.IO.File.Delete(reqAppFile);
                            }
                            if (ForceApprov)
                            {
                                // FixMe ToDo !!!
                                // deve chiamare metodo x approvare, in MP-PROG, la directory dei
                                // documenti caricati.. x ora segnaposto con file (così se scansiona
                                // trova e approva)...
                                System.IO.File.WriteAllText(reqAppFile, authKey);
                            }
                        }
                    }
                }
                catch (IOException ex)
                {
                    Log.Error($"{ZipFile.FileName} error on upload (Err: 3): {ex.Message}");
                    uploadResult.ErrorCode = 3;
                }
            }
            uploadResults.Add(uploadResult);
            Log.Info($"ZipUpload backup completed | CodInst: {CodInst} | CodApp: {CodApp} | {uploadResults.Count} files");

            return new CreatedResult(resourcePath, uploadResult);
        }

        #endregion Public Methods

        #region Protected Properties

        /// <summary>
        /// Dataservice x accesso DB
        /// </summary>
        protected ApiDataService dataService { get; set; }

        #endregion Protected Properties

        #region Protected Methods

        /// <summary>
        /// Restituisce size calcolata
        /// </summary>
        /// <param name="origSize"></param>
        /// <returns></returns>
        protected string CalcSize(long origSize)
        {
            return MeasureUtils.SizeSuffix(origSize, 1);
        }

        /// <summary>
        /// Calcolo correetto mimetype da nome file
        /// </summary>
        /// <param name="fileName"></param>
        /// <returns></returns>
        protected string GetMimeType(string fileName)
        {
            var provider = new FileExtensionContentTypeProvider();
            string contentType;
            if (!provider.TryGetContentType(fileName, out contentType))
            {
                contentType = "application/octet-stream";
            }
            return contentType;
        }

        #endregion Protected Methods

        #region Private Fields

        private static IConfiguration _configuration;

        /// <summary>
        /// Classe per logging
        /// </summary>
        private static Logger Log = LogManager.GetCurrentClassLogger();

        private readonly IWebHostEnvironment env;

        #endregion Private Fields
    }
}