Fix OverflowException during video finalization (#670)

TwitchDownloaderCore/VideoDownloader.cs

@@ -166,8 +166,8 @@ private int RunFfmpegVideoCopy(IProgress<ProgressReport> progress, string downlo
             };
 
             var videoLength = TimeSpan.Zero;
-            var videoLengthRegex = new Regex(@"(?<=^\s?\s?Duration: )\d\d:\d\d:\d\d\.\d\d", RegexOptions.Multiline);
-            var encodingTimeRegex = new Regex(@"(?<=time=)\d\d:\d\d:\d\d\.\d\d", RegexOptions.Compiled);
+            var videoLengthRegex = new Regex(@"(?<=^\s?\s?Duration:\s)(\d\d):(\d\d):(\d\d)\.(\d\d)", RegexOptions.Multiline);
+            var encodingTimeRegex = new Regex(@"(?<=time=)(\d\d):(\d\d):(\d\d)\.(\d\d)", RegexOptions.Compiled);
             var logQueue = new ConcurrentQueue<string>();
 
             process.ErrorDataReceived += (sender, e) =>
@@ -183,7 +183,12 @@ private int RunFfmpegVideoCopy(IProgress<ProgressReport> progress, string downlo
                     if (!videoLengthMatch.Success)
                         return;
 
-                    videoLength = TimeSpan.Parse(videoLengthMatch.ValueSpan);
+                    // TimeSpan.Parse insists that hours cannot be greater than 24, thus we must use the TimeSpan ctor.
+                    if (!int.TryParse(videoLengthMatch.Groups[1].ValueSpan, out var hours)) return;
+                    if (!int.TryParse(videoLengthMatch.Groups[2].ValueSpan, out var minutes)) return;
+                    if (!int.TryParse(videoLengthMatch.Groups[3].ValueSpan, out var seconds)) return;
+                    if (!int.TryParse(videoLengthMatch.Groups[4].ValueSpan, out var milliseconds)) return;
+                    videoLength = new TimeSpan(0, hours, minutes, seconds, milliseconds);
                     return;
                 }
 
@@ -212,7 +217,13 @@ private static void HandleFfmpegOutput(string output, Regex encodingTimeRegex, T
             if (!encodingTimeMatch.Success)
                 return;
 
-            var encodingTime = TimeSpan.Parse(encodingTimeMatch.ValueSpan);
+            // TimeSpan.Parse insists that hours cannot be greater than 24, thus we must use the TimeSpan ctor.
+            if (!int.TryParse(encodingTimeMatch.Groups[1].ValueSpan, out var hours)) return;
+            if (!int.TryParse(encodingTimeMatch.Groups[2].ValueSpan, out var minutes)) return;
+            if (!int.TryParse(encodingTimeMatch.Groups[3].ValueSpan, out var seconds)) return;
+            if (!int.TryParse(encodingTimeMatch.Groups[4].ValueSpan, out var milliseconds)) return;
+            var encodingTime = new TimeSpan(0, hours, minutes, seconds, milliseconds);
+
             var percent = (int)(encodingTime.TotalMilliseconds / videoLength.TotalMilliseconds * 100);
 
             progress.Report(new ProgressReport(ReportType.SameLineStatus, $"Finalizing Video {percent}% [4/4]"));