Reworked FFmpeg path discovery and always display to user

1) Reworked FFmpeg and FFprobe path discovery (CLI switch, Custom xml, system $PATH, UI update trigger).  Removed FFMpeg folder from Emby.Server.Implementations.  All path discovery now in MediaEncoder.

2) Always display FFmpeg path to user in Transcode page.

3) Allow user to remove a Custome FFmpeg path and return to using system $PATH (or --ffmpeg if available).

4) Remove unused code associated with 'prebuilt' FFmpeg.

5) Much improved logging during path discovery.

4 files changed, 7 insertions, 238 deletions

diff --git a/Emby.Server.Implementations/ApplicationHost.cs b/Emby.Server.Implementations/ApplicationHost.cs
index 94d2cd5da..2c0d0e746 100644
--- a/Emby.Server.Implementations/ApplicationHost.cs
+++ b/Emby.Server.Implementations/ApplicationHost.cs
@@ -28,7 +28,6 @@ using Emby.Server.Implementations.Data;
 using Emby.Server.Implementations.Devices;
 using Emby.Server.Implementations.Diagnostics;
 using Emby.Server.Implementations.Dto;
-using Emby.Server.Implementations.FFMpeg;
 using Emby.Server.Implementations.HttpServer;
 using Emby.Server.Implementations.HttpServer.Security;
 using Emby.Server.Implementations.IO;
@@ -792,7 +791,8 @@ namespace Emby.Server.Implementations
             ChapterManager = new ChapterManager(LibraryManager, LoggerFactory, ServerConfigurationManager, ItemRepository);
             serviceCollection.AddSingleton(ChapterManager);
 
-            RegisterMediaEncoder(serviceCollection);
+            MediaEncoder = new MediaBrowser.MediaEncoding.Encoder.MediaEncoder(LoggerFactory, JsonSerializer, StartupOptions.FFmpegPath, StartupOptions.FFprobePath, ServerConfigurationManager, FileSystemManager, () => SubtitleEncoder, () => MediaSourceManager, ProcessFactory, 5000);
+            serviceCollection.AddSingleton(MediaEncoder);
 
             EncodingManager = new MediaEncoder.EncodingManager(FileSystemManager, LoggerFactory, MediaEncoder, ChapterManager, LibraryManager);
             serviceCollection.AddSingleton(EncodingManager);
@@ -908,83 +908,25 @@ namespace Emby.Server.Implementations
             return new ImageProcessor(LoggerFactory, ServerConfigurationManager.ApplicationPaths, FileSystemManager, ImageEncoder, () => LibraryManager, () => MediaEncoder);
         }
 
-        protected virtual FFMpegInstallInfo GetFfmpegInstallInfo()
-        {
-            var info = new FFMpegInstallInfo();
-
-            // Windows builds: http://ffmpeg.zeranoe.com/builds/
-            // Linux builds: http://johnvansickle.com/ffmpeg/
-            // OS X builds: http://ffmpegmac.net/
-            // OS X x64: http://www.evermeet.cx/ffmpeg/
-
-            if (EnvironmentInfo.OperatingSystem == MediaBrowser.Model.System.OperatingSystem.Linux)
-            {
-                info.FFMpegFilename = "ffmpeg";
-                info.FFProbeFilename = "ffprobe";
-                info.ArchiveType = "7z";
-                info.Version = "20170308";
-            }
-            else if (EnvironmentInfo.OperatingSystem == MediaBrowser.Model.System.OperatingSystem.Windows)
-            {
-                info.FFMpegFilename = "ffmpeg.exe";
-                info.FFProbeFilename = "ffprobe.exe";
-                info.Version = "20170308";
-                info.ArchiveType = "7z";
-            }
-            else if (EnvironmentInfo.OperatingSystem == MediaBrowser.Model.System.OperatingSystem.OSX)
-            {
-                info.FFMpegFilename = "ffmpeg";
-                info.FFProbeFilename = "ffprobe";
-                info.ArchiveType = "7z";
-                info.Version = "20170308";
-            }
-
-            return info;
-        }
-
-        protected virtual FFMpegInfo GetFFMpegInfo()
-        {
-            return new FFMpegLoader(ApplicationPaths, FileSystemManager, GetFfmpegInstallInfo())
-                .GetFFMpegInfo(StartupOptions);
-        }
-
         /// <summary>
         /// Registers the media encoder.
         /// </summary>
         /// <returns>Task.</returns>
-        private void RegisterMediaEncoder(IServiceCollection serviceCollection)
+        private void RegisterMediaEncoder(IAssemblyInfo assemblyInfo)
         {
-            string encoderPath = null;
-            string probePath = null;
-
-            var info = GetFFMpegInfo();
-
-            encoderPath = info.EncoderPath;
-            probePath = info.ProbePath;
-            var hasExternalEncoder = string.Equals(info.Version, "external", StringComparison.OrdinalIgnoreCase);
-
-            var mediaEncoder = new MediaBrowser.MediaEncoding.Encoder.MediaEncoder(
+            MediaEncoder = new MediaBrowser.MediaEncoding.Encoder.MediaEncoder(
                 LoggerFactory,
                 JsonSerializer,
-                encoderPath,
-                probePath,
-                hasExternalEncoder,
+                StartupOptions.FFmpegPath,
+                StartupOptions.FFprobePath,
                 ServerConfigurationManager,
                 FileSystemManager,
-                LiveTvManager,
-                IsoManager,
-                LibraryManager,
-                ChannelManager,
-                SessionManager,
                 () => SubtitleEncoder,
                 () => MediaSourceManager,
-                HttpClient,
-                ZipClient,
                 ProcessFactory,
                 5000);
 
-            MediaEncoder = mediaEncoder;
-            serviceCollection.AddSingleton(MediaEncoder);
+            RegisterSingleInstance(MediaEncoder);
         }
 
         /// <summary>
diff --git a/Emby.Server.Implementations/FFMpeg/FFMpegInfo.cs b/Emby.Server.Implementations/FFMpeg/FFMpegInfo.cs
deleted file mode 100644
index 60cd7b3d7..000000000
--- a/Emby.Server.Implementations/FFMpeg/FFMpegInfo.cs
+++ /dev/null
@@ -1,24 +0,0 @@
-namespace Emby.Server.Implementations.FFMpeg
-{
-    /// <summary>
-    /// Class FFMpegInfo
-    /// </summary>
-    public class FFMpegInfo
-    {
-        /// <summary>
-        /// Gets or sets the path.
-        /// </summary>
-        /// <value>The path.</value>
-        public string EncoderPath { get; set; }
-        /// <summary>
-        /// Gets or sets the probe path.
-        /// </summary>
-        /// <value>The probe path.</value>
-        public string ProbePath { get; set; }
-        /// <summary>
-        /// Gets or sets the version.
-        /// </summary>
-        /// <value>The version.</value>
-        public string Version { get; set; }
-    }
-}
diff --git a/Emby.Server.Implementations/FFMpeg/FFMpegInstallInfo.cs b/Emby.Server.Implementations/FFMpeg/FFMpegInstallInfo.cs
deleted file mode 100644
index fa9cb5e01..000000000
--- a/Emby.Server.Implementations/FFMpeg/FFMpegInstallInfo.cs
+++ /dev/null
@@ -1,17 +0,0 @@
-namespace Emby.Server.Implementations.FFMpeg
-{
-    public class FFMpegInstallInfo
-    {
-        public string Version { get; set; }
-        public string FFMpegFilename { get; set; }
-        public string FFProbeFilename { get; set; }
-        public string ArchiveType { get; set; }
-
-        public FFMpegInstallInfo()
-        {
-            Version = "Path";
-            FFMpegFilename = "ffmpeg";
-            FFProbeFilename = "ffprobe";
-        }
-    }
-}
diff --git a/Emby.Server.Implementations/FFMpeg/FFMpegLoader.cs b/Emby.Server.Implementations/FFMpeg/FFMpegLoader.cs
deleted file mode 100644
index bbf51dd24..000000000
--- a/Emby.Server.Implementations/FFMpeg/FFMpegLoader.cs
+++ /dev/null
@@ -1,132 +0,0 @@
-using System;
-using System.Collections.Generic;
-using System.IO;
-using System.Linq;
-using MediaBrowser.Common.Configuration;
-using MediaBrowser.Model.IO;
-
-namespace Emby.Server.Implementations.FFMpeg
-{
-    public class FFMpegLoader
-    {
-        private readonly IApplicationPaths _appPaths;
-        private readonly IFileSystem _fileSystem;
-        private readonly FFMpegInstallInfo _ffmpegInstallInfo;
-
-        public FFMpegLoader(IApplicationPaths appPaths, IFileSystem fileSystem, FFMpegInstallInfo ffmpegInstallInfo)
-        {
-            _appPaths = appPaths;
-            _fileSystem = fileSystem;
-            _ffmpegInstallInfo = ffmpegInstallInfo;
-        }
-
-        public FFMpegInfo GetFFMpegInfo(IStartupOptions options)
-        {
-            var customffMpegPath = options.FFmpegPath;
-            var customffProbePath = options.FFprobePath;
-
-            if (!string.IsNullOrWhiteSpace(customffMpegPath) && !string.IsNullOrWhiteSpace(customffProbePath))
-            {
-                return new FFMpegInfo
-                {
-                    ProbePath = customffProbePath,
-                    EncoderPath = customffMpegPath,
-                    Version = "external"
-                };
-            }
-
-            var downloadInfo = _ffmpegInstallInfo;
-
-            var prebuiltFolder = _appPaths.ProgramSystemPath;
-            var prebuiltffmpeg = Path.Combine(prebuiltFolder, downloadInfo.FFMpegFilename);
-            var prebuiltffprobe = Path.Combine(prebuiltFolder, downloadInfo.FFProbeFilename);
-            if (File.Exists(prebuiltffmpeg) && File.Exists(prebuiltffprobe))
-            {
-                return new FFMpegInfo
-                {
-                    ProbePath = prebuiltffprobe,
-                    EncoderPath = prebuiltffmpeg,
-                    Version = "external"
-                };
-            }
-
-            var version = downloadInfo.Version;
-
-            if (string.Equals(version, "0", StringComparison.OrdinalIgnoreCase))
-            {
-                return new FFMpegInfo();
-            }
-
-            var rootEncoderPath = Path.Combine(_appPaths.ProgramDataPath, "ffmpeg");
-            var versionedDirectoryPath = Path.Combine(rootEncoderPath, version);
-
-            var info = new FFMpegInfo
-            {
-                ProbePath = Path.Combine(versionedDirectoryPath, downloadInfo.FFProbeFilename),
-                EncoderPath = Path.Combine(versionedDirectoryPath, downloadInfo.FFMpegFilename),
-                Version = version
-            };
-
-            Directory.CreateDirectory(versionedDirectoryPath);
-
-            var excludeFromDeletions = new List<string> { versionedDirectoryPath };
-
-            if (!File.Exists(info.ProbePath) || !File.Exists(info.EncoderPath))
-            {
-                // ffmpeg not present. See if there's an older version we can start with
-                var existingVersion = GetExistingVersion(info, rootEncoderPath);
-
-                // No older version. Need to download and block until complete
-                if (existingVersion == null)
-                {
-                    return new FFMpegInfo();
-                }
-                else
-                {
-                    info = existingVersion;
-                    versionedDirectoryPath = Path.GetDirectoryName(info.EncoderPath);
-                    excludeFromDeletions.Add(versionedDirectoryPath);
-                }
-            }
-
-            // Allow just one of these to be overridden, if desired.
-            if (!string.IsNullOrWhiteSpace(customffMpegPath))
-            {
-                info.EncoderPath = customffMpegPath;
-            }
-            if (!string.IsNullOrWhiteSpace(customffProbePath))
-            {
-                info.ProbePath = customffProbePath;
-            }
-
-            return info;
-        }
-
-        private FFMpegInfo GetExistingVersion(FFMpegInfo info, string rootEncoderPath)
-        {
-            var encoderFilename = Path.GetFileName(info.EncoderPath);
-            var probeFilename = Path.GetFileName(info.ProbePath);
-
-            foreach (var directory in _fileSystem.GetDirectoryPaths(rootEncoderPath))
-            {
-                var allFiles = _fileSystem.GetFilePaths(directory, true).ToList();
-
-                var encoder = allFiles.FirstOrDefault(i => string.Equals(Path.GetFileName(i), encoderFilename, StringComparison.OrdinalIgnoreCase));
-                var probe = allFiles.FirstOrDefault(i => string.Equals(Path.GetFileName(i), probeFilename, StringComparison.OrdinalIgnoreCase));
-
-                if (!string.IsNullOrWhiteSpace(encoder) &&
-                    !string.IsNullOrWhiteSpace(probe))
-                {
-                    return new FFMpegInfo
-                    {
-                        EncoderPath = encoder,
-                        ProbePath = probe,
-                        Version = Path.GetFileName(Path.GetDirectoryName(probe))
-                    };
-                }
-            }
-
-            return null;
-        }
-    }
-}