1 files changed, 49 insertions, 4 deletions
diff --git a/MediaBrowser.Api/Playback/Progressive/BaseProgressiveStreamingService.cs b/MediaBrowser.Api/Playback/Progressive/BaseProgressiveStreamingService.cs
index a2c20e38f..1c36289c5 100644
--- a/MediaBrowser.Api/Playback/Progressive/BaseProgressiveStreamingService.cs
+++ b/MediaBrowser.Api/Playback/Progressive/BaseProgressiveStreamingService.cs
@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Globalization;
 using System.IO;
 using System.Threading;
 using System.Threading.Tasks;
@@ -13,6 +14,7 @@ using MediaBrowser.Controller.Net;
 using MediaBrowser.Model.IO;
 using MediaBrowser.Model.MediaInfo;
 using MediaBrowser.Model.Serialization;
+using MediaBrowser.Model.Services;
 using Microsoft.Net.Http.Headers;
 
 namespace MediaBrowser.Api.Playback.Progressive
@@ -279,10 +281,9 @@ namespace MediaBrowser.Api.Playback.Progressive
         /// <returns>Task{System.Object}.</returns>
         private async Task<object> GetStaticRemoteStreamResult(StreamState state, Dictionary<string, string> responseHeaders, bool isHeadRequest, CancellationTokenSource cancellationTokenSource)
         {
-            string useragent = null;
-            state.RemoteHttpHeaders.TryGetValue("User-Agent", out useragent);
+            state.RemoteHttpHeaders.TryGetValue(HeaderNames.UserAgent, out var useragent);
 
-            var trySupportSeek = false;
+            const bool trySupportSeek = false;
 
             var options = new HttpRequestOptions
             {
@@ -317,6 +318,12 @@ namespace MediaBrowser.Api.Playback.Progressive
                 responseHeaders[HeaderNames.AcceptRanges] = "none";
             }
 
+            // Seeing cases of -1 here
+            if (response.ContentLength.HasValue && response.ContentLength.Value >= 0)
+            {
+                responseHeaders[HeaderNames.ContentLength] = response.ContentLength.Value.ToString(CultureInfo.InvariantCulture);
+            }
+
             if (isHeadRequest)
             {
                 using (response)
@@ -356,10 +363,31 @@ namespace MediaBrowser.Api.Playback.Progressive
             var contentType = state.GetMimeType(outputPath);
 
             // TODO: The isHeadRequest is only here because ServiceStack will add Content-Length=0 to the response
+            var contentLength = state.EstimateContentLength || isHeadRequest ? GetEstimatedContentLength(state) : null;
+
+            if (contentLength.HasValue)
+            {
+                responseHeaders[HeaderNames.ContentLength] = contentLength.Value.ToString(CultureInfo.InvariantCulture);
+            }
+
             // Headers only
             if (isHeadRequest)
             {
-                return ResultFactory.GetResult(null, Array.Empty<byte>(), contentType, responseHeaders);
+                var streamResult = ResultFactory.GetResult(null, Array.Empty<byte>(), contentType, responseHeaders);
+
+                if (streamResult is IHasHeaders hasHeaders)
+                {
+                    if (contentLength.HasValue)
+                    {
+                        hasHeaders.Headers[HeaderNames.ContentLength] = contentLength.Value.ToString(CultureInfo.InvariantCulture);
+                    }
+                    else
+                    {
+                        hasHeaders.Headers.Remove(HeaderNames.ContentLength);
+                    }
+                }
+
+                return streamResult;
             }
 
             var transcodingLock = ApiEntryPoint.Instance.GetTranscodingLock(outputPath);
@@ -397,5 +425,22 @@ namespace MediaBrowser.Api.Playback.Progressive
                 transcodingLock.Release();
             }
         }
+
+        /// <summary>
+        /// Gets the length of the estimated content.
+        /// </summary>
+        /// <param name="state">The state.</param>
+        /// <returns>System.Nullable{System.Int64}.</returns>
+        private long? GetEstimatedContentLength(StreamState state)
+        {
+            var totalBitrate = state.TotalOutputBitrate ?? 0;
+
+            if (totalBitrate > 0 && state.RunTimeTicks.HasValue)
+            {
+                return Convert.ToInt64(totalBitrate * TimeSpan.FromTicks(state.RunTimeTicks.Value).TotalSeconds / 8);
+            }
+
+            return null;
+        }
     }
 }