Implement flatpak package manager

src/UniGetUI.Avalonia.slnx

@@ -177,6 +177,12 @@
       <Platform Solution="*|x64" Project="x64" />
     </Project>
   </Folder>
+  <Folder Name="/UniGetUI.PackageEngine.Managers.Flatpak/">
+    <Project Path="UniGetUI.PackageEngine.Managers.Flatpak/UniGetUI.PackageEngine.Managers.Flatpak.csproj">
+      <Platform Solution="*|arm64" Project="arm64" />
+      <Platform Solution="*|x64" Project="x64" />
+    </Project>
+  </Folder>
   <Folder Name="/UniGetUI.PackageEngine.Managers.Vcpkg/">
     <Project Path="UniGetUI.PackageEngine.Managers.Vcpkg/UniGetUI.PackageEngine.Managers.Vcpkg.csproj">
       <Platform Solution="*|arm64" Project="arm64" />

src/UniGetUI.Interface.Enums/Enums.cs

@@ -89,6 +89,7 @@ public enum IconType
         Dnf = '\uE945',
         Pacman = '\uE946',
         Snap = '\uE947',
+        Flatpak = '\uE948',
     }
 
     public class NotificationArguments

src/UniGetUI.PackageEngine.Managers.Flatpak/Flatpak.cs

@@ -0,0 +1,224 @@
+using System.Diagnostics;
+using UniGetUI.Core.Tools;
+using UniGetUI.Interface.Enums;
+using UniGetUI.PackageEngine.Classes.Manager;
+using UniGetUI.PackageEngine.Enums;
+using UniGetUI.PackageEngine.ManagerClasses.Classes;
+using UniGetUI.PackageEngine.ManagerClasses.Manager;
+using UniGetUI.PackageEngine.PackageClasses;
+
+namespace UniGetUI.PackageEngine.Managers.FlatpakManager;
+
+public partial class Flatpak : PackageManager
+{
+    private static readonly string[] FLATPAK_PATHS =
+    [
+        "/usr/bin/flatpak",
+        "/usr/local/bin/flatpak",
+    ];
+
+    public Flatpak()
+    {
+        Dependencies = [];
+
+        var flathubSource = new ManagerSource(this, "flathub", new Uri("https://dl.flathub.org/repo/"));
+
+        Capabilities = new ManagerCapabilities
+        {
+            CanRunAsAdmin = true,
+            CanSkipIntegrityChecks = true,
+            SupportsCustomSources = true,
+            Sources = new SourceCapabilities
+            {
+                KnowsPackageCount = false,
+                KnowsUpdateDate = false,
+            },
+            SupportsProxy = ProxySupport.No,
+            SupportsProxyAuth = false,
+        };
+
+        Properties = new ManagerProperties
+        {
+            Name = "Flatpak",
+            Description = CoreTools.Translate(
+                "The universal Linux package manager for desktop applications.<br>Contains: <b>Flatpak applications from configured remotes</b>"
+            ),
+            IconId = IconType.Flatpak,
+            ColorIconId = "flatpak",
+            ExecutableFriendlyName = "flatpak",
+            InstallVerb = "install",
+            UpdateVerb = "update",
+            UninstallVerb = "uninstall",
+            DefaultSource = flathubSource,
+            KnownSources = [flathubSource],
+        };
+
+        SourcesHelper = new FlatpakSourceHelper(this);
+        DetailsHelper = new FlatpakPkgDetailsHelper(this);
+        OperationHelper = new FlatpakPkgOperationHelper(this);
+    }
+
+    public override IReadOnlyList<string> FindCandidateExecutableFiles()
+    {
+        var candidates = new List<string>(CoreTools.WhichMultiple("flatpak"));
+        foreach (var path in FLATPAK_PATHS)
+        {
+            if (File.Exists(path) && !candidates.Contains(path))
+                candidates.Add(path);
+        }
+        return candidates;
+    }
+
+    protected override void _loadManagerExecutableFile(
+        out bool found,
+        out string path,
+        out string callArguments)
+    {
+        (found, path) = GetExecutableFile();
+        callArguments = "";
+    }
+
+    protected override void _loadManagerVersion(out string version)
+    {
+        using var p = new Process
+        {
+            StartInfo = new ProcessStartInfo
+            {
+                FileName = Status.ExecutablePath,
+                Arguments = "--version",
+                UseShellExecute = false,
+                RedirectStandardOutput = true,
+                RedirectStandardError = true,
+                CreateNoWindow = true,
+            },
+        };
+        p.Start();
+        var line = p.StandardOutput.ReadLine()?.Trim() ?? "";
+        version = line.Replace("Flatpak ", "").Trim();
+        p.StandardError.ReadToEnd();
+        p.WaitForExit();
+    }
+
+    public override void RefreshPackageIndexes()
+    {
+        using var p = new Process
+        {
+            StartInfo = new ProcessStartInfo
+            {
+                FileName = Status.ExecutablePath,
+                Arguments = "update --appstream",
+                UseShellExecute = false,
+                RedirectStandardOutput = true,
+                RedirectStandardError = true,
+                CreateNoWindow = true,
+            },
+        };
+        IProcessTaskLogger logger = TaskLogger.CreateNew(LoggableTaskType.RefreshIndexes, p);
+        p.Start();
+        logger.AddToStdOut(p.StandardOutput.ReadToEnd());
+        logger.AddToStdErr(p.StandardError.ReadToEnd());
+        p.WaitForExit();
+        logger.Close(p.ExitCode);
+    }
+
+    protected override IReadOnlyList<Package> FindPackages_UnSafe(string query)
+    {
+        using var p = new Process
+        {
+            StartInfo = new ProcessStartInfo
+            {
+                FileName = Status.ExecutablePath,
+                Arguments = $"search {CoreTools.EnsureSafeQueryString(query)}",
+                UseShellExecute = false,
+                RedirectStandardOutput = true,
+                RedirectStandardError = true,
+                CreateNoWindow = true,
+            },
+        };
+        p.StartInfo.Environment["LANG"] = "C";
+        p.StartInfo.Environment["LC_ALL"] = "C";
+        IProcessTaskLogger logger = TaskLogger.CreateNew(LoggableTaskType.FindPackages, p);
+        p.Start();
+
+        List<string> outputLines = [];
+        while (p.StandardOutput.ReadLine() is { } line)
+        {
+            logger.AddToStdOut(line);
+            outputLines.Add(line);
+        }
+
+        logger.AddToStdErr(p.StandardError.ReadToEnd());
+        p.WaitForExit();
+        logger.Close(p.ExitCode);
+
+        return ParseSearchResults(outputLines, DefaultSource, this);
+    }
+
+    protected override IReadOnlyList<Package> GetInstalledPackages_UnSafe()
+    {
+        using var p = new Process
+        {
+            StartInfo = new ProcessStartInfo
+            {
+                FileName = Status.ExecutablePath,
+                Arguments = "list --app --columns=application,version,branch,origin,name",
+                UseShellExecute = false,
+                RedirectStandardOutput = true,
+                RedirectStandardError = true,
+                CreateNoWindow = true,
+            },
+        };
+        p.StartInfo.Environment["LANG"] = "C";
+        p.StartInfo.Environment["LC_ALL"] = "C";
+        IProcessTaskLogger logger = TaskLogger.CreateNew(LoggableTaskType.ListInstalledPackages, p);
+        p.Start();
+
+        List<string> outputLines = [];
+        while (p.StandardOutput.ReadLine() is { } line)
+        {
+            logger.AddToStdOut(line);
+            outputLines.Add(line);
+        }
+
+        logger.AddToStdErr(p.StandardError.ReadToEnd());
+        p.WaitForExit();
+        logger.Close(p.ExitCode);
+
+        return ParseInstalledPackages(outputLines, DefaultSource, this);
+    }
+
+    protected override IReadOnlyList<Package> GetAvailableUpdates_UnSafe()
+    {
+        using var p = new Process
+        {
+            StartInfo = new ProcessStartInfo
+            {
+                FileName = Status.ExecutablePath,
+                Arguments = "remote-ls --updates --columns=application,version,branch,origin,name",
+                UseShellExecute = false,
+                RedirectStandardOutput = true,
+                RedirectStandardError = true,
+                CreateNoWindow = true,
+            },
+        };
+
+        p.StartInfo.Environment["LANG"] = "C";
+        p.StartInfo.Environment["LC_ALL"] = "C";
+        IProcessTaskLogger logger = TaskLogger.CreateNew(LoggableTaskType.ListUpdates, p);
+
+        p.Start();
+
+        List<string> outputLines = [];
+        while (p.StandardOutput.ReadLine() is { } line)
+        {
+            logger.AddToStdOut(line);
+            outputLines.Add(line);
+        }
+
+        logger.AddToStdErr(p.StandardError.ReadToEnd());
+        p.WaitForExit();
+        logger.Close(p.ExitCode);
+
+        return ParseAvailableUpdates(outputLines, DefaultSource, this, GetInstalledPackages_UnSafe());
+    }
+}