Downloader dedup

src/BizHawk.Client.EmuHawk/AVOut/FFmpegDownloaderForm.cs

@@ -1,162 +1,38 @@
 using System.IO;
-using System.Linq;
-using System.Threading;
-using System.Windows.Forms;
 
 using BizHawk.Common;
+using BizHawk.Common.IOExtensions;
 
 namespace BizHawk.Client.EmuHawk
 {
-	/// <summary>
-	/// Downloads FFmpeg
-	/// </summary>
-	public partial class FFmpegDownloaderForm : Form
+	public sealed class FFmpegDownloaderForm : DownloaderForm
 	{
-		public FFmpegDownloaderForm()
-		{
-			InitializeComponent();
-
-			txtLocation.Text = FFmpegService.FFmpegPath;
-			txtUrl.Text = FFmpegService.Url;
-
-			if (OSTailoredCode.IsUnixHost) textBox1.Text = string.Join("\n", textBox1.Text.Split('\n').Take(3)) + "\n\n(Linux user: If installing manually, you can use a symlink.)";
-		}
-
-		private int pct = 0;
-		private bool exiting = false;
-		private bool succeeded = false;
-		private bool failed = false;
-
-		private void ThreadProc()
-		{
-			Download();
-		}
-
-		private void Download()
-		{
-			//the temp file is owned by this thread
-			var fn = TempFileManager.GetTempFilename("ffmpeg_download", ".7z", false);
-
-			try
-			{
-				DirectoryInfo parentDir = new(Path.GetDirectoryName(FFmpegService.FFmpegPath)!);
-				if (!parentDir.Exists) parentDir.Create();
-				using var fs = File.Create(FFmpegService.FFmpegPath); // check writable before bothering with the download
-				using (var evt = new ManualResetEvent(false))
-				{
-					using (var client = new System.Net.WebClient())
-					{
-						System.Net.ServicePointManager.SecurityProtocol = System.Net.SecurityProtocolType.Tls12;
-						client.DownloadFileAsync(new Uri(FFmpegService.Url), fn);
-						client.DownloadProgressChanged += (object sender, System.Net.DownloadProgressChangedEventArgs e) =>
-						{
-							pct = e.ProgressPercentage;
-						};
-						client.DownloadFileCompleted += (object sender, System.ComponentModel.AsyncCompletedEventArgs e) =>
-						{
-							//we don't really need a status. we'll just try to unzip it when it's done
-							evt.Set();
-						};
-
-						for (; ; )
-						{
-							if (evt.WaitOne(10))
-								break;
-
-							//if the gui thread ordered an exit, cancel the download and wait for it to acknowledge
-							if (exiting)
-							{
-								client.CancelAsync();
-								evt.WaitOne();
-								break;
-							}
-						}
-					}
-				}
-
-				//throw new Exception("test of download failure");
-
-				//if we were ordered to exit, bail without wasting any more time
-				if (exiting)
-					return;
+		protected override string ComponentName
+			=> "FFmpeg";
 
-				//try acquiring file
-				using (var hf = new HawkFile(fn))
-				{
-					using (var exe = OSTailoredCode.IsUnixHost ? hf.BindArchiveMember("ffmpeg") : hf.BindFirstOf(".exe"))
-					{
-						//last chance. exiting, don't dump the new ffmpeg file
-						if (exiting)
-							return;
-						exe!.GetStream().CopyTo(fs);
-						fs.Dispose();
-						if (OSTailoredCode.IsUnixHost)
-						{
-							OSTailoredCode.ConstructSubshell("chmod", $"+x {FFmpegService.FFmpegPath}", checkStdout: false).Start();
-							Thread.Sleep(50); // Linux I/O flush idk
-						}
-					}
-				}
+		protected override string DownloadTemp { get; }
+			= TempFileManager.GetTempFilename("ffmpeg_download", ".7z", delete: false);
 
-				//make sure it worked
-				if (!FFmpegService.QueryServiceAvailable()) throw new Exception("download failed");
-
-				succeeded = true;
-			}
-			catch (Exception e)
-			{
-				failed = true;
-				Util.DebugWriteLine($"FFmpeg download failed with:\n{e}");
-			}
-			finally
-			{
-				try { File.Delete(fn); }
-				catch { }
-			}
-		}
-
-		private void btnDownload_Click(object sender, EventArgs e)
-		{
-			btnDownload.Text = "Downloading...";
-			btnDownload.Enabled = false;
-			failed = false;
-			succeeded = false;
-			pct = 0;
-			var t = new Thread(ThreadProc);
-			t.Start();
-		}
-
-		private void btnCancel_Click(object sender, EventArgs e)
+		public FFmpegDownloaderForm()
 		{
-			Close();
+			Description = "BizHawk relies on a specific version of FFmpeg. No other version will do. The wrong version will be ignored. There is no way to override this behavior."
+				+ "\n\nThe required version could not be found."
+				+ (OSTailoredCode.IsUnixHost
+					? "\n\n(Linux user: If installing manually, you can use a symlink.)"
+					: "\n\nUse this dialog to download it automatically, or download it yourself from the URL below and place it in the specified location.");
+			DownloadFrom = FFmpegService.Url;
+			DownloadTo = FFmpegService.FFmpegPath;
 		}
 
-		protected override void OnClosed(EventArgs e)
-		{
-			//inform the worker thread that it needs to try terminating without doing anything else
-			//(it will linger on in background for a bit til it can service this)
-			exiting = true;
-		}
+		protected override Stream GetExtractionStream(HawkFile downloaded)
+			=> (OSTailoredCode.IsUnixHost
+				? downloaded.BindArchiveMember("ffmpeg")!
+				: downloaded.BindFirstOf(".exe")).GetStream();
 
-		private void timer1_Tick(object sender, EventArgs e)
-		{
-			//if it's done, close the window. the user will be smart enough to reopen it
-			if (succeeded)
-				Close();
-			if (failed)
-			{
-				failed = false;
-				pct = 0;
-				btnDownload.Text = "FAILED - Download Again";
-				btnDownload.Enabled = true;
-			}
-			progressBar1.Value = pct;
-		}
+		protected override bool PostChmodCheck()
+			=> FFmpegService.QueryServiceAvailable();
 
-		private void linkLabel1_LinkClicked(object sender, LinkLabelLinkClickedEventArgs e)
-		{
-			System.Diagnostics.Process.Start(FFmpegService.Url);
-		}
+		protected override bool PreChmodCheck(FileStream extracted)
+			=> SHA256Checksum.ComputeDigestHex(extracted.ReadAllBytes()) == FFmpegService.DownloadSHA256Checksum;
 	}
 }
-