Skips download if file exists (unless overridden)

New Feature: If a episode has already been downloaded, then it won't be
downloaded when the program runs again - it will be skipped.  Previously
downloaded episodes are matched based on the file size and the file
name.

If a download already exists, but the size of the file is different from
what is being downloaded, then it is considered to be an incomplete
download and will be overwritten (resuming downloads is not supported at
this time).

This behavior can be overwritten using the -o (or -overwrite) flag,
which will cause an existing download to be overwritten regardless of
whether or not the download completed fully on a previous download
attempt.

SimpleTv.Downloader/Arguments.cs

@@ -0,0 +1,96 @@
+using Fclp;
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Reflection;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace SimpleTv.Downloader
+{
+    public static class Arguments
+    {
+        public static FluentCommandLineParser<Configuration> Setup()
+        {
+            var p = new FluentCommandLineParser<Configuration>();
+
+            p.Setup(arg => arg.Username)
+                .As('u', "username")
+                .WithDescription("Username for logging into Simple.Tv")
+                .Required();
+
+            p.Setup(arg => arg.Password)
+                .As('p', "password")
+                .WithDescription("Password for logging into Simple.Tv")
+                .Required();
+
+            // Later on, -d / -dryrun will be used to do a dry run (parsing without downloading)
+
+            p.Setup(arg => arg.ShowIncludeFilter)
+                .As('i', "includeShows")
+                .WithDescription("[optional] Type in show(s) to include.  Wildcards accepted.")
+                .SetDefault("*");
+
+            p.Setup(arg => arg.ShowExcludeFilter)
+                .As('x', "excludeShows")
+                .WithDescription("[optional] Type in show(s) to exclude.  Wildcards accepted.")
+                .SetDefault(string.Empty);
+
+            p.Setup(arg => arg.ServerIncludeFilter)
+                .As('s', "includeServers")
+                .WithDescription("[optional] Type in media server(s) to include.  Wildcards accepted.")
+                .SetDefault("*");
+
+            p.Setup(arg => arg.ServerExcludeFilter)
+                .As('e', "excludeServers")
+                .WithDescription("[optional] Type in media server(s) to exclude.  Wildcards accepted.")
+                .SetDefault(string.Empty);
+
+            p.Setup(arg => arg.DownloadFolder)
+                .As('f', "downloadFolder")
+                .WithDescription("[optional] Folder to place downloaded recordings in.  Defaults to current working directory.")
+                .SetDefault(Directory.GetCurrentDirectory());
+
+            p.Setup(arg => arg.FolderFormat)
+                .As('t', "folderformat")
+                .WithDescription("[optional] The folder format for saving the recording, relative to the downloadfolder.  Defaults to Plex format defined at https://support.plex.tv/hc/en-us/articles/200220687-Naming-Series-Season-Based-TV-Shows")
+                .SetDefault("{ShowName}\\Season {SeasonNumber00}");
+
+            p.Setup(arg => arg.FilenameFormat)
+                .As('n', "filenameformat")
+                .WithDescription("[optional] The filename format for saving the recording.  Defaults to Plex format defined at https://support.plex.tv/hc/en-us/articles/200220687-Naming-Series-Season-Based-TV-Shows")
+                .SetDefault("{ShowName} - S{SeasonNumber00}E{EpisodeNumber00} - {EpisodeName}.mp4");
+
+            p.Setup(arg => arg.OverwriteExistingDownloads)
+                .As('o', "overwrite")
+                .WithDescription("[optional] Will overwrite previously downloaded episodes.  If you do not set this, episodes that have previously been downloaded will be skipped.")
+                .SetDefault(false);
+
+            p.Setup(arg => arg.LogHttpCalls)
+                .As('l', "logHttpCalls")
+                .WithDescription("[optional] Will save a log of all http calls, helpful for debugging errors")
+                .SetDefault(false);
+
+            p.Setup(arg => arg.Reboot)
+                .As('r', "reboot")
+                .WithDescription("Used to reboot Simple.TV DVRs.  Can be used with -s and -t.")
+                .SetDefault(false);
+
+            p.SetupHelp("?", "help")
+                .WithHeader(string.Format(
+                    "SimpleTV Downloader\n" +
+                    "Version {0}\n" +
+                    "\n" +
+                    "SimpleTV Downloader can download your Simple.Tv recordings.  \r\n" +
+                    "Usage:\r\n" +
+                    "\t{1} -u [email protected] -p \"P@ssw0Rd\" -d c:\\tvshows -i \"NCIS*\"",
+                    Assembly.GetExecutingAssembly().GetName().Version, 
+                    Path.GetFileName(Assembly.GetEntryAssembly().Location)
+                ))
+                .Callback(text => Console.WriteLine(text));
+
+            return p;
+        }
+    }
+}

SimpleTv.Downloader/Configuration.cs

@@ -8,6 +8,7 @@ public class Configuration
         public string DownloadFolder { get; set; }
         public string FolderFormat { get; set; }
         public string FilenameFormat { get; set; }
+        public bool OverwriteExistingDownloads { get; set; }
         public string ShowIncludeFilter { get; set; }
         public string ShowExcludeFilter { get; set; }
         public string ServerIncludeFilter { get; set; }

SimpleTv.Downloader/Downloader.cs

@@ -138,10 +138,20 @@ public void Download()
                                             episode.EpisodeName,
                                             episode.DateTime.IfNotNull(d => d.Value.ToString("d")),
                                             episode.Error));
-                                    } else
+                                        continue;
+                                    }
+
+                                    var downloadDetails = tvClient.PrepareDownload(episode, config.DownloadFolder, config.FolderFormat, config.FilenameFormat);
+                                    if (downloadDetails.FileExistsWithSameSize && !config.OverwriteExistingDownloads)
                                     {
-                                        tvClient.DownloadEpisode(episode, config.DownloadFolder, config.FolderFormat, config.FilenameFormat);
+                                        Console.WriteLine(string.Format(
+                                            "Skipping \"{0}\" from {1}: Episode already downloaded",
+                                            episode.EpisodeName,
+                                            episode.DateTime.IfNotNull(d => d.Value.ToString("d"))));
+                                        continue;
                                     }
+
+                                    tvClient.DownloadEpisode(downloadDetails);
                                 }
                                 catch (StreamNotFoundException e)
                                 {

SimpleTv.Downloader/Program.cs

@@ -10,11 +10,9 @@ namespace SimpleTv.Downloader
 {
     class Program
     {
-        private static string execName = Path.GetFileName(System.Reflection.Assembly.GetEntryAssembly().Location);
-
         static void Main(string[] args)
         {
-            var p = SetupArguments();
+            var p = Arguments.Setup();
             var result = p.Parse(args);
             if (result.HasErrors)
             {
@@ -55,82 +53,5 @@ static void Main(string[] args)
                 }
             }
         }
-
-        public static FluentCommandLineParser<Configuration> SetupArguments()
-        {
-            var p = new FluentCommandLineParser<Configuration>();
-
-            p.Setup(arg => arg.Username)
-                .As('u', "username")
-                .WithDescription("Username for logging into Simple.Tv")
-                .Required();
-
-            p.Setup(arg => arg.Password)
-                .As('p', "password")
-                .WithDescription("Password for logging into Simple.Tv")
-                .Required();
-
-            // Later on, -d / -dryrun will be used to do a dry run (parsing without downloading)
-
-            p.Setup(arg => arg.ShowIncludeFilter)
-                .As('i', "includeShows")
-                .WithDescription("[optional] Type in show(s) to include.  Wildcards accepted.")
-                .SetDefault("*");
-
-            p.Setup(arg => arg.ShowExcludeFilter)
-                .As('x', "excludeShows")
-                .WithDescription("[optional] Type in show(s) to exclude.  Wildcards accepted.")
-                .SetDefault(string.Empty);
-
-            p.Setup(arg => arg.ServerIncludeFilter)
-                .As('s', "includeServers")
-                .WithDescription("[optional] Type in media server(s) to include.  Wildcards accepted.")
-                .SetDefault("*");
-
-            p.Setup(arg => arg.ServerExcludeFilter)
-                .As('e', "excludeServers")
-                .WithDescription("[optional] Type in media server(s) to exclude.  Wildcards accepted.")
-                .SetDefault(string.Empty);
-
-            p.Setup(arg => arg.DownloadFolder)
-                .As('f', "downloadFolder")
-                .WithDescription("[optional] Folder to place downloaded recordings in.  Defaults to current working directory.")
-                .SetDefault(Directory.GetCurrentDirectory());
-
-            p.Setup(arg => arg.FolderFormat)
-                .As('t', "folderformat")
-                .WithDescription("[optional] The folder format for saving the recording, relative to the downloadfolder.  Defaults to Plex format defined at https://support.plex.tv/hc/en-us/articles/200220687-Naming-Series-Season-Based-TV-Shows")
-                .SetDefault("{ShowName}\\Season {SeasonNumber00}");
-
-            p.Setup(arg => arg.FilenameFormat)
-                .As('n', "filenameformat")
-                .WithDescription("[optional] The filename format for saving the recording.  Defaults to Plex format defined at https://support.plex.tv/hc/en-us/articles/200220687-Naming-Series-Season-Based-TV-Shows")
-                .SetDefault("{ShowName} - S{SeasonNumber00}E{EpisodeNumber00} - {EpisodeName}.mp4");
-
-            p.Setup(arg => arg.LogHttpCalls)
-                .As('l', "logHttpCalls")
-                .WithDescription("[optional] Will save a log of all http calls, helpful for debugging errors")
-                .SetDefault(false);
-
-            p.Setup(arg => arg.Reboot)
-                .As('r', "reboot")
-                .WithDescription("Used to reboot Simple.TV DVRs.  Can be used with -s and -t.")
-                .SetDefault(false);
-
-            p.SetupHelp("?", "help")
-                .WithHeader(string.Format(
-                    "SimpleTV Downloader\n" + 
-                    "Version {0}\n" +
-                    "\n" +
-                    "SimpleTV Downloader can download your Simple.Tv recordings.  \r\n" +
-                    "Usage:\r\n" +
-                    "\t{1} -u [email protected] -p \"P@ssw0Rd\" -d c:\\tvshows -i \"NCIS*\"",
-                    Assembly.GetExecutingAssembly().GetName().Version, execName
-                ))
-                .Callback(text => Console.WriteLine(text));
-
-            return p;
-        }
-
     }
 }

SimpleTv.Downloader/SimpleTv.Downloader.csproj

@@ -74,6 +74,7 @@
     <Reference Include="System.Xml" />
   </ItemGroup>
   <ItemGroup>
+    <Compile Include="Arguments.cs" />
     <Compile Include="Configuration.cs" />
     <Compile Include="StvConsole.cs" />
     <Compile Include="Downloader.cs" />

SimpleTv.Sdk/Http/ISimpleTvHttpClient.cs

@@ -18,5 +18,6 @@ public interface ISimpleTvHttpClient
         List<Episode> GetEpisodes(Show show);
         string GetEpisodeLocation(Episode episode);
         void Download(Uri fullPathToVideo, string fileName, string episodeName);
+        long GetFileSize(Uri uri);
     }
 }

SimpleTv.Sdk/Http/SimpleTvHttpClient.cs

@@ -293,5 +293,10 @@ private void Client_DownloadProgressChanged(object sender, DownloadProgressChang
                 Console.Write("     ");
             }
         }
+
+        public long GetFileSize(Uri uri)
+        {
+            return webClient.GetFileSize(uri);
+        }
     }
 }

SimpleTv.Sdk/Models/DownloadDetails.cs

@@ -0,0 +1,17 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace SimpleTv.Sdk.Models
+{
+    public class DownloadDetails
+    {
+        public Episode Episode { get; set; }
+        public bool FileExistsWithSameSize { get; set; }
+        public Uri FullUriToVideo { get; set; }
+        public long DownloadSize { get;  set;}
+        public string FilePathAndName { get; set; }
+    }
+}

SimpleTv.Sdk/SimpleTv.Sdk.csproj

@@ -70,6 +70,7 @@
     <Compile Include="Http\ISimpleTvHttpClient.cs" />
     <Compile Include="Http\IWebClient.cs" />
     <Compile Include="Http\SimpleTvHttpClient.cs" />
+    <Compile Include="Models\DownloadDetails.cs" />
     <Compile Include="Models\Episode.cs" />
     <Compile Include="Models\INamed.cs" />
     <Compile Include="Models\MediaServer.cs" />

SimpleTv.Sdk/SimpleTvClient.cs

@@ -6,6 +6,7 @@
 using SimpleTv.Sdk.Http;
 using SimpleTv.Sdk.Diagnostics;
 using System;
+using System.IO;
 using SimpleTv.Sdk.Naming;
 using System.Linq;
 
@@ -61,12 +62,21 @@ public void Reboot(MediaServer server)
             tvHttpClient.Reboot(server);
         }
 
-        public void DownloadEpisode(Episode episode, string downloadFolder, string folderFormat, string filenameFormat)
+        public DownloadDetails PrepareDownload(Episode episode, string baseFolder, string folderFormat, string fileNameFormat)
         {
-            var fileName = episode.GenerateFileName(downloadFolder, folderFormat, filenameFormat);
-            var fullPathToVideo = new Uri(episode.Show.Server.StreamBaseUrl + tvHttpClient.GetEpisodeLocation(episode));
+            var downloadDetails = new DownloadDetails();
+            downloadDetails.Episode = episode;
+            downloadDetails.FilePathAndName = episode.GenerateFileName(baseFolder, folderFormat, fileNameFormat);
+            downloadDetails.FullUriToVideo = new Uri(episode.Show.Server.StreamBaseUrl + tvHttpClient.GetEpisodeLocation(episode));
+            downloadDetails.DownloadSize = tvHttpClient.GetFileSize(downloadDetails.FullUriToVideo);
+            downloadDetails.FileExistsWithSameSize = File.Exists(downloadDetails.FilePathAndName) && (new FileInfo(downloadDetails.FilePathAndName)).Length == downloadDetails.DownloadSize;
 
-            tvHttpClient.Download(fullPathToVideo, fileName, episode.EpisodeName);
+            return downloadDetails;
+        }
+
+        public void DownloadEpisode(DownloadDetails downloadDetails)
+        {
+            tvHttpClient.Download(downloadDetails.FullUriToVideo, downloadDetails.FilePathAndName, downloadDetails.Episode.EpisodeName);
         }
     }
 }

doc/Parameters.md

@@ -61,6 +61,15 @@ The `-t` or `-folderformat` and `-n` or `-filenameformat` can
 customize the folder names and filenames of the downloaded episodes.  For more
 details, see the [NamingFormat documentation](doc/NamingFormat.md).
 
+## Overwrite Existing episodes
+
+By default, if the downloader finds that an episode has already been downloaded,
+it will skip the episode and not download it again.  The episode to be downloaded
+is checked against existing files based on the filename and the size of the file.
+
+The `-o` or `-overwrite` flag will cause the downloader to overwrite the
+previously downloaded files.
+
 ## Reboot
 
 The `-r` or `-reboot` is used to reboot the SimpleTV DVR.  This can be used