using System;
using System.IO;
using System.Linq;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Options;

namespace vCloud.Server.Videos.Controllers
{
    /// <summary>
    /// upload video controller
    /// </summary>
    [Produces("application/json")]
    [Route("api/Videos")]
    public class VideosController : Controller
    {
        private string _tmpExtension ="tmp";
        protected AppSettings AppSettings { get; set; }
        public VideosController(IOptions<AppSettings> settings)
        {
            AppSettings = settings.Value;
        }
        [HttpGet]
        public string Get()
        {
            return "";
        }

        /// <summary>
        /// get server file md5 API
        /// </summary>
        /// <returns></returns>
        [HttpGet("GetRsume")]
        public string GetRsume()
        {
            var statusCode = 0;
            string responseMsg;
            try
            {
                var md5str = HttpContext.Request.Query["md5str"].FirstOrDefault();
                if (string.IsNullOrEmpty(md5str))
                {
                    statusCode = -1;
                    responseMsg = statusCode + "&";
                    return responseMsg;
                }

                var clientid = HttpContext.Request.Query["clientid"].FirstOrDefault();
                var videoDirectory = AppSettings.StoageVideoFolder;
                if (!Directory.Exists(videoDirectory))
                {
                    Directory.CreateDirectory(videoDirectory);
                }

                var path = Path.Combine(videoDirectory, md5str);
                var saveFilePath = path;
                if (System.IO.File.Exists(saveFilePath))
                {
                    var fileLength = GetFileLength(saveFilePath);
                    var fileName = Path.GetFileName(saveFilePath);
                    var videoUrl = GetVideoUrl(fileName);
                    responseMsg = fileLength + "&" + videoUrl;
                    return responseMsg;
                }

                var fileNameWithoutExtension = Path.GetFileNameWithoutExtension(path);
                var tmppathWithoutExtension = Path.Combine(videoDirectory, fileNameWithoutExtension + "&" + clientid);
                var tmpFilePath = Path.ChangeExtension(tmppathWithoutExtension, _tmpExtension);
                if (System.IO.File.Exists(tmpFilePath))
                {
                    //if other client uploading file 
                    var fileLength = GetFileLength(tmpFilePath);
                    responseMsg = fileLength + "&";
                    return responseMsg;
                }
            }
            catch (Exception e)
            {
                Console.WriteLine(e);
                statusCode = -1;
            }

            responseMsg = statusCode + "&";
            return responseMsg;
        }

        private string GetVideoUrl(string filename)
        {
            var playVideosServer = AppSettings.ServerUrl;
            if (AppSettings.ServerUrl.LastIndexOf('/') != AppSettings.ServerUrl.Length - 1)
            {
                playVideosServer += "/";
            }

           var videoUrl = playVideosServer + "Vod" + "/" + filename;
            return videoUrl;
        }

        /// <summary>
        /// upload video API eg.http://localhost:8891/api/Videos/UploadVideo
        /// </summary>
        /// <returns></returns>
        [HttpPost("UploadVideo")]
        public string UploadVideo()
        {
            try
            {
                var file = HttpContext.Request.Body;
                var filename = HttpContext.Request.Query["filename"].FirstOrDefault();
                var clientid = HttpContext.Request.Query["clientid"].FirstOrDefault();
                var videoDirectory = AppSettings.StoageVideoFolder;
                if (!Directory.Exists(videoDirectory))
                {
                    Directory.CreateDirectory(videoDirectory);
                }

                var path = Path.Combine(videoDirectory, filename);
                var finish = this.SaveAs(path, file, clientid, out long endPosition);
                string videoUrl = string.Empty;
                if (finish)
                {
                    videoUrl= GetVideoUrl(filename);
                }

                HttpContext.Response.StatusCode = 200;
                var responseMsg = endPosition + "&" + videoUrl;
                return responseMsg;

            }
            catch (Exception e)
            {
                Console.WriteLine(e);
                HttpContext.Response.StatusCode = 500;
            }

            return String.Empty;
        }

        /// <summary>
        /// save file to server
        /// </summary>
        /// <param name="saveFilePath"></param>
        /// <param name="stream"></param>
        /// <param name="endPosition"></param>
        /// <returns></returns>
        private bool SaveAs(string saveFilePath, System.IO.Stream stream, string clientid, out long endPosition)
        {
            bool finish = false;
            var targetFilePath = saveFilePath;
            var targetTmpFilePath = Path.ChangeExtension(targetFilePath, _tmpExtension);
            var fileNameWithoutExtension = Path.GetFileNameWithoutExtension(saveFilePath);
            var dir = Path.GetDirectoryName(saveFilePath);
            var tmppathWithoutExtension = Path.Combine(dir, fileNameWithoutExtension + "&" + clientid);
            var tmpFilePath = Path.ChangeExtension(tmppathWithoutExtension, _tmpExtension);
            if (System.IO.File.Exists(targetFilePath))
            {
                if (System.IO.File.Exists(tmpFilePath))
                {
                    System.IO.File.Delete(tmpFilePath);
                }
                endPosition = GetFileLength(targetFilePath);
                return true;
            }
           
            long lStartPos = 0;
            int startPosition = 0;
            endPosition = 0;
            long fileLength = 0;
            var contentRange = HttpContext.Request.Headers["Content-Range"].ToString();

            //bytes 10000-19999/1157632
            if (!string.IsNullOrEmpty(contentRange))
            {
                contentRange = contentRange.Replace("bytes", "").Trim();
                string[] ranges = contentRange.Split('/');
                string[] positioRanges = ranges[0].Split('-');
                startPosition = int.Parse(positioRanges[0]);
                endPosition = long.Parse(positioRanges[1]);
                fileLength = long.Parse(ranges[1]);
            }

            System.IO.FileStream fs;
            if (System.IO.File.Exists(saveFilePath))
            {
                fs = System.IO.File.OpenWrite(saveFilePath);
                lStartPos = fs.Length;
            }
            else
            {
                if (System.IO.File.Exists(tmpFilePath))
                {
                    fs = System.IO.File.OpenWrite(tmpFilePath);
                    lStartPos = fs.Length;

                }
                else
                {
                    fs = new System.IO.FileStream(tmpFilePath, System.IO.FileMode.Create);
                    lStartPos = 0;
                }

                saveFilePath = tmpFilePath;
            }

            if (lStartPos > endPosition)
            {
                fs.Close();
                endPosition = lStartPos;
                return finish;
            }
            else if (lStartPos < startPosition)
            {
                lStartPos = startPosition;
            }
            else if (lStartPos > startPosition && lStartPos < endPosition)
            {
                lStartPos = startPosition;
            }

            fs.Seek(lStartPos, System.IO.SeekOrigin.Current);
            var writeLength = 1024;
            byte[] nbytes = new byte[writeLength];
            int nReadSize = 0;
            nReadSize = stream.Read(nbytes, 0, writeLength);
            while (nReadSize > 0)
            {
                fs.Write(nbytes, 0, nReadSize);
                nReadSize = stream.Read(nbytes, 0, writeLength);
            }

            finish = fs.Length == fileLength;
            endPosition = fs.Length;
            fs.Close();
            if (finish)
            {
                if (System.IO.File.Exists(targetFilePath))
                {
                    System.IO.File.Delete(saveFilePath);
                }
                if (System.IO.File.Exists(saveFilePath))
                {
                    var tmpfileNameWithoutExtension = Path.GetFileNameWithoutExtension(saveFilePath);
                    if (tmpfileNameWithoutExtension.Contains("&"))
                    {
                        System.IO.File.Move(saveFilePath, targetTmpFilePath);
                        saveFilePath = targetTmpFilePath;
                    }
                    System.IO.File.Move(saveFilePath, targetFilePath);
                }
            }

            return finish;
        }

        private long GetFileLength(string filePath)
        {
            var fs = System.IO.File.OpenRead(filePath);
            var fslength = fs.Length;
            fs.Close();
            return fslength;
        }
    }
}