From 9db4ba75b45a2a55da2feabf973a459865d1acb7 Mon Sep 17 00:00:00 2001
From: Kerry Cao <kcyq98@gmail.com>
Date: Tue, 11 Apr 2023 21:55:30 -0600
Subject: [PATCH] features to auto download ffmpeg binaries added

---
 FFMpegCore.Test/DownloaderTests.cs     | 27 +++++++++++
 FFMpegCore/Helpers/FFMpegDownloader.cs | 64 ++++++++++++++++++++++++++
 2 files changed, 91 insertions(+)
 create mode 100644 FFMpegCore.Test/DownloaderTests.cs
 create mode 100644 FFMpegCore/Helpers/FFMpegDownloader.cs

diff --git a/FFMpegCore.Test/DownloaderTests.cs b/FFMpegCore.Test/DownloaderTests.cs
new file mode 100644
index 0000000..301078a
--- /dev/null
+++ b/FFMpegCore.Test/DownloaderTests.cs
@@ -0,0 +1,27 @@
+using System.Runtime.InteropServices;
+using FFMpegCore.Helpers;
+
+namespace FFMpegCore.Test;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+public class DownloaderTests
+{
+    [TestClass]
+    public class FFMpegDownloaderTest
+    {
+        [TestMethod]
+        public void GetLatestVersionTest()
+        {
+            if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
+            {
+                var files = FFMpegDownloader.GetLatestVersion();
+                Assert.IsTrue(files.Count == 3);
+            }
+            else
+            {
+                Assert.Inconclusive("This test is only for Windows");
+            }
+            
+        }
+    }
+}
diff --git a/FFMpegCore/Helpers/FFMpegDownloader.cs b/FFMpegCore/Helpers/FFMpegDownloader.cs
new file mode 100644
index 0000000..7767683
--- /dev/null
+++ b/FFMpegCore/Helpers/FFMpegDownloader.cs
@@ -0,0 +1,64 @@
+using System.ComponentModel;
+using System.Net;
+using System.IO;
+using System.IO.Compression;
+
+
+namespace FFMpegCore.Helpers;
+using System.Runtime.InteropServices;
+
+/// <summary>
+/// Downloads the latest FFMpeg binaries from GitHub. Only supported for windows at the moment.
+/// </summary>
+public class FFMpegDownloader // this class is built to be easily modified to support other platforms
+{
+    /// <summary>
+    /// List of URLs to download FFMpeg from.
+    /// </summary>
+    private static Dictionary<string, string> FFMpegDownloadUrls = new()
+    {
+        { "windows", "https://github.com/BtbN/FFmpeg-Builds/releases/download/latest/ffmpeg-master-latest-win64-gpl.zip" }
+    };
+
+    public static List<string> GetLatestVersion()
+    {
+        var os = GetOSPlatform();
+        var zipStream = DownloadFFMpeg(new Uri(FFMpegDownloadUrls[os]));
+        return ExtractAndSave(zipStream);
+    }
+
+    private static MemoryStream DownloadFFMpeg(Uri address)
+    {
+        var client = new WebClient();
+        var zipStream = new MemoryStream(client.DownloadData(address));
+        zipStream.Position = 0;
+
+        return zipStream;
+    }
+    
+    private static List<string> ExtractAndSave(Stream zipStream)
+    {
+        using var archive = new ZipArchive(zipStream, ZipArchiveMode.Read);
+        List<string> files = new();
+        foreach (var entry in archive.Entries)
+        {
+            if (entry.Name is "ffmpeg.exe" or "ffmpeg" or "ffprobe.exe")
+            {
+                entry.ExtractToFile(Path.Combine(GlobalFFOptions.Current.BinaryFolder, entry.Name), true);
+                files.Add(Path.Combine(GlobalFFOptions.Current.BinaryFolder, entry.Name));
+            }
+        }
+
+        return files;
+    }
+    
+    private static string GetOSPlatform()
+    {
+        if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
+        {
+            return "windows";
+        }
+
+        throw new PlatformNotSupportedException("Auto download is only supported on Windows.");
+    }
+}