Allow an empty Discover search to list every WinGet package

src/UniGetUI.Avalonia/ViewModels/SoftwarePages/PackagesPageViewModel.cs

@@ -618,7 +618,10 @@ partial void OnGlobalQueryTextChanged(string value)
             {
                 MegaQueryText = "";
                 MegaQueryVisible = true;
-                Loader?.ClearPackages(emitFinishSignal: false);
+                if (Loader is DiscoverablePackagesLoader discoverLoader)
+                    discoverLoader.ResetSearch();
+                else
+                    Loader?.ClearPackages(emitFinishSignal: false);
             }
             else
             {
@@ -677,7 +680,7 @@ private Func<PackageWrapper, bool> BuildPackageFilter(out string query)
         foreach (var f in filters) normalizedQuery = f(normalizedQuery);
         query = normalizedQuery;
 
-        Func<IPackage, bool> matchFunc = SearchMode switch
+        Func<IPackage, bool> matchFunc = normalizedQuery.Length == 0 ? _ => true : SearchMode switch
         {
             SearchMode.Name => pkg => FilterHelpers.NameContains(pkg, normalizedQuery, filters),
             SearchMode.Id => pkg => FilterHelpers.IdContains(pkg, normalizedQuery, filters),
@@ -719,7 +722,7 @@ private void UpdateFilteredState(string query)
         {
             bool noQuery = string.IsNullOrWhiteSpace(query);
             BackgroundText = noQuery ? NoPackagesText : NoMatchesText;
-            BackgroundTextVisible = !MegaQueryBoxEnabled || !noQuery;
+            BackgroundTextVisible = !MegaQueryBoxEnabled || !noQuery || !MegaQueryVisible;
             LoadingImageVisible = false;
             NoPackagesImageVisible = noQuery && BackgroundTextVisible && NoPackagesImage is not null;
         }

src/UniGetUI.PackageEngine.Enums/Enums.cs

@@ -1,5 +1,10 @@
 namespace UniGetUI.PackageEngine.Enums
 {
+    public static class SearchLimits
+    {
+        public const int MaxEmptyQueryResultsPerSource = 100;
+    }
+
     /// <summary>
     /// Represents the installation scope of a package
     /// </summary>

src/UniGetUI.PackageEngine.Enums/ManagerCapabilities.cs

@@ -43,6 +43,7 @@ public struct ManagerCapabilities
         public bool SupportsCustomScopesOnUpdate = true;
         public bool SupportsCustomScopesOnUninstall = true;
         public bool SupportsPreRelease = false;
+        public bool SupportsEmptySearchQuery = false;
         public bool SerializesOperations = false;
         public bool SupportsCustomLocations = false;
         public bool SupportsCustomSources = false;

src/UniGetUI.PackageEngine.Managers.WinGet/ClientHelpers/NativeWinGetHelper.cs

@@ -184,7 +184,7 @@
         List<Package> packages = [];
         INativeTaskLogger logger = Manager.TaskLogger.CreateNew(LoggableTaskType.FindPackages);
         Dictionary<
-            (PackageCatalogReference, PackageMatchField),
+            (PackageCatalogReference, PackageMatchField?),
             Task<FindPackagesResult>
         > FindPackageTasks = [];
 
@@ -203,24 +203,27 @@
             ConnectResult result = CatalogReference.Connect();
             if (result.Status == ConnectResultStatus.Ok)
             {
-                foreach (
-                    var filter_type in new[]
-                    {
-                        PackageMatchField.Name,
-                        PackageMatchField.Id,
-                        PackageMatchField.Moniker,
-                    }
-                )
+                PackageMatchField?[] filterTypes = query.Length == 0
+                    ? [null]
+                    : [PackageMatchField.Name, PackageMatchField.Id, PackageMatchField.Moniker];
+                foreach (PackageMatchField? filter_type in filterTypes)
                 {
                     FindPackagesOptions PackageFilters = Factory.CreateFindPackagesOptions();
 
-                    logger.Log("Generating filters...");
-                    // Name filter
-                    PackageMatchFilter FilterName = Factory.CreatePackageMatchFilter();
-                    FilterName.Field = filter_type;
-                    FilterName.Value = query;
-                    FilterName.Option = PackageFieldMatchOption.ContainsCaseInsensitive;
-                    PackageFilters.Filters.Add(FilterName);
+                    if (filter_type is { } field)
+                    {
+                        logger.Log("Generating filters...");
+                        // Name filter
+                        PackageMatchFilter FilterName = Factory.CreatePackageMatchFilter();
+                        FilterName.Field = field;
+                        FilterName.Value = query;
+                        FilterName.Option = PackageFieldMatchOption.ContainsCaseInsensitive;
+                        PackageFilters.Filters.Add(FilterName);
+                    }
+                    else
+                    {
+                        PackageFilters.ResultLimit = (uint)SearchLimits.MaxEmptyQueryResultsPerSource;
+                    }
 
                     try
                     {
@@ -349,7 +352,7 @@
                     nativePackage.DefaultInstallVersion.PackageCatalog.Info.Name
                 );
 
                 string? reportedVersion = nativePackage.InstalledVersion.Version;
                 string version = WinGetPkgOperationHelper.ResolveReportedInstalledVersion(
                     nativePackage.Id,
                     reportedVersion
@@ -429,7 +432,7 @@
                     source = Manager.GetLocalSource(nativePackage.Id);
                 }
 
                 string? reportedVersion = nativePackage.InstalledVersion.Version;
                 string version = WinGetPkgOperationHelper.ResolveReportedInstalledVersion(
                     nativePackage.Id,
                     reportedVersion

src/UniGetUI.PackageEngine.Managers.WinGet/ClientHelpers/PingetCliHelper.cs

@@ -113,10 +113,35 @@ public IReadOnlyList<Package> GetInstalledPackages_UnSafe()
 
     public IReadOnlyList<Package> FindPackages_UnSafe(string query)
     {
-        SearchResponse result = RunJson<SearchResponse>(
-            LoggableTaskType.FindPackages,
-            $"search {Quote(query)} --output json"
-        );
+        if (query.Length == 0)
+        {
+            return Manager
+                .SourcesHelper.GetSources()
+                .SelectMany(SearchSourceForBrowse)
+                .ToArray();
+        }
+
+        return SearchPackages($"search {Quote(query)} --output json");
+    }
+
+    private Package[] SearchSourceForBrowse(IManagerSource source)
+    {
+        try
+        {
+            return SearchPackages(
+                $"search {Quote(string.Empty)} --source {Quote(source.Name)} --count {SearchLimits.MaxEmptyQueryResultsPerSource} --output json"
+            );
+        }
+        catch (Exception ex)
+        {
+            Logger.Warn($"Could not list the packages of the WinGet source {source.Name}: {ex.Message}");
+            return [];
+        }
+    }
+
+    private Package[] SearchPackages(string arguments)
+    {
+        SearchResponse result = RunJson<SearchResponse>(LoggableTaskType.FindPackages, arguments);
 
         return result
             .Matches.Select(match =>

src/UniGetUI.PackageEngine.Managers.WinGet/ClientHelpers/WinGetCliHelper.cs

@@ -1,5 +1,7 @@
 using System.Diagnostics;
 using System.Text;
+using System.Text.Json;
+using System.Text.Json.Serialization;
 using System.Text.RegularExpressions;
 using UniGetUI.Core.Logging;
 using UniGetUI.Core.Tools;
@@ -11,7 +13,7 @@
 
 namespace UniGetUI.PackageEngine.Managers.WingetManager;
 
-internal sealed class WinGetCliHelper : IWinGetManagerHelper
+internal sealed partial class WinGetCliHelper : IWinGetManagerHelper
 {
     // "winget search a" returns ~12k results; cap to the most relevant to avoid the freeze/RAM spike.
     private const int MAX_SEARCH_RESULTS = 100;
@@ -270,6 +272,80 @@ IEnumerable<string> outputLines
     }
 
     public IReadOnlyList<Package> FindPackages_UnSafe(string query)
+    {
+        if (query.Length == 0)
+        {
+            return GetSourcesForBrowse()
+                .SelectMany(source => SearchPackages(query, source, SearchLimits.MaxEmptyQueryResultsPerSource))
+                .ToArray();
+        }
+
+        return SearchPackages(query, null, MAX_SEARCH_RESULTS);
+    }
+
+    private List<IManagerSource> GetSourcesForBrowse()
+    {
+        using var _cliLock = WinGet.AcquireCliLock();
+        List<IManagerSource> sources = [];
+        using Process p = new()
+        {
+            StartInfo = new()
+            {
+                FileName = _cliExecutablePath,
+                Arguments = Manager.Status.ExecutableCallArgs + " source export",
+                RedirectStandardOutput = true,
+                RedirectStandardError = true,
+                UseShellExecute = false,
+                CreateNoWindow = true,
+                StandardOutputEncoding = Encoding.UTF8,
+            },
+        };
+
+        IProcessTaskLogger logger = Manager.TaskLogger.CreateNew(LoggableTaskType.ListSources, p);
+
+        if (CoreTools.IsAdministrator())
+        {
+            string WinGetTemp = AppPaths.RedirectTempToElevatedDirectory(p.StartInfo);
+            logger.AddToStdErr(
+                $"[WARN] Redirecting %TEMP% folder to {WinGetTemp}, since UniGetUI was run as admin"
+            );
+        }
+
+        p.Start();
+
+        foreach (string name in ParseExportedSourceNames(ReadOutputLines(p, logger)))
+        {
+            sources.Add(Manager.SourcesHelper.Factory.GetSourceOrDefault(name));
+        }
+
+        logger.AddToStdErr(p.StandardError.ReadToEnd());
+        p.WaitForExit();
+        logger.Close(p.ExitCode);
+        return sources;
+    }
+
+    internal static IEnumerable<string> ParseExportedSourceNames(IEnumerable<string> outputLines)
+    {
+        foreach (string line in outputLines)
+        {
+            string? name;
+            try
+            {
+                name = JsonSerializer.Deserialize(line, WinGetCliJsonContext.Default.WinGetExportedSource)?.Name;
+            }
+            catch (JsonException)
+            {
+                continue;
+            }
+
+            if (!string.IsNullOrWhiteSpace(name))
+            {
+                yield return name;
+            }
+        }
+    }
+
+    private List<Package> SearchPackages(string query, IManagerSource? source, int count)
     {
         using var _cliLock = WinGet.AcquireCliLock();
         List<Package> Packages = [];
@@ -282,8 +358,10 @@ public IReadOnlyList<Package> FindPackages_UnSafe(string query)
                     Manager.Status.ExecutableCallArgs
                     + " search \""
                     + query
-                    + "\" --count "
-                    + MAX_SEARCH_RESULTS
+                    + "\""
+                    + (source is null ? "" : " --source \"" + source.Name + "\"")
+                    + " --count "
+                    + count
                     + " --accept-source-agreements "
                     + WinGet.GetProxyArgument(),
                 RedirectStandardOutput = true,
@@ -306,7 +384,7 @@ public IReadOnlyList<Package> FindPackages_UnSafe(string query)
 
         p.Start();
 
-        Packages.AddRange(ParseFoundPackages(Manager, ReadOutputLines(p, logger)));
+        Packages.AddRange(ParseFoundPackages(Manager, ReadOutputLines(p, logger), source));
 
         logger.AddToStdErr(p.StandardError.ReadToEnd());
         p.WaitForExit();
@@ -317,7 +395,8 @@ public IReadOnlyList<Package> FindPackages_UnSafe(string query)
 
     internal static IReadOnlyList<Package> ParseFoundPackages(
         WinGet manager,
-        IEnumerable<string> outputLines
+        IEnumerable<string> outputLines,
+        IManagerSource? queriedSource = null
     )
     {
         List<Package> packages = [];
@@ -338,7 +417,7 @@ IEnumerable<string> outputLines
 
                 IManagerSource source =
                     sourceName.Length == 0
-                        ? manager.DefaultSource
+                        ? queriedSource ?? manager.DefaultSource
                         : manager.SourcesHelper.Factory.GetSourceOrDefault(sourceName);
 
                 packages.Add(new Package(name, id, version, source, manager));
@@ -512,4 +591,9 @@ public IReadOnlyList<IManagerSource> GetSources_UnSafe()
         logger.Close(p.ExitCode);
         return sources;
     }
+
+    internal sealed record WinGetExportedSource(string? Name);
+
+    [JsonSerializable(typeof(WinGetExportedSource))]
+    internal sealed partial class WinGetCliJsonContext : JsonSerializerContext { }
 }

src/UniGetUI.PackageEngine.Managers.WinGet/WinGet.cs

@@ -128,6 +128,7 @@ public WinGet()
                 SupportsCustomSources = true,
                 SupportsCustomPackageIcons = true,
                 SupportsCustomPackageScreenshots = true,
+                SupportsEmptySearchQuery = true,
                 Sources = new SourceCapabilities
                 {
                     KnowsPackageCount = false,

src/UniGetUI.PackageEngine.PackageLoader/DiscoverablePackagesLoader.cs

@@ -1,6 +1,7 @@
 using UniGetUI.Core.SettingsEngine;
 using UniGetUI.Core.Tools;
 using UniGetUI.Interface.Enums;
+using UniGetUI.PackageEngine.Enums;
 using UniGetUI.PackageEngine.Interfaces;
 
 namespace UniGetUI.PackageEngine.PackageLoader
@@ -13,7 +14,7 @@ public class DiscoverablePackagesLoader : AbstractPackageLoader
         // tags and renders thousands of packages, freezing the UI and spiking RAM.
         private const int MAX_RESULTS_PER_MANAGER = 100;
 
-        private string QUERY_TEXT = string.Empty;
+        private string? QUERY_TEXT;
         private volatile bool _pendingReload;
 
         public DiscoverablePackagesLoader(IReadOnlyList<IPackageManager> managers)
@@ -45,9 +46,15 @@ public async Task ReloadPackages(string query)
             await ReloadPackages();
         }
 
+        public void ResetSearch()
+        {
+            QUERY_TEXT = null;
+            ClearPackages(emitFinishSignal: false);
+        }
+
         public override async Task ReloadPackages()
         {
-            if (QUERY_TEXT == "")
+            if (QUERY_TEXT is null)
             {
                 return;
             }
@@ -76,23 +83,38 @@ public void SetManagerSearched(IPackageManager manager, bool searched)
             => Settings.SetDictionaryItem(Settings.K.ExcludedSearchManagers, manager.Name, !searched);
 
         protected override bool WillQueryAnyManager()
-            => Managers.Any(manager => manager.IsReady() && IsManagerSearched(manager));
+        {
+            string? query = QUERY_TEXT;
+            return Managers.Any(manager =>
+                manager.IsReady() && IsManagerSearched(manager) && CanSearch(manager, query));
+        }
+
+        private static bool CanSearch(IPackageManager manager, string? query)
+            => query != string.Empty || manager.Capabilities.SupportsEmptySearchQuery;
 
         protected override IReadOnlyList<IPackage> LoadPackagesFromManager(IPackageManager manager)
         {
-            if (!IsManagerSearched(manager))
+            string? query = QUERY_TEXT;
+            if (query is null || !IsManagerSearched(manager) || !CanSearch(manager, query))
             {
                 return [];
             }
 
-            string text = QUERY_TEXT;
-            text = CoreTools.EnsureSafeQueryString(text);
-            if (text == string.Empty)
+            string text = CoreTools.EnsureSafeQueryString(query);
+            if (text.Length == 0 && query.Length > 0)
             {
                 return [];
             }
 
             IReadOnlyList<IPackage> found = manager.FindPackages(text);
+            if (text.Length == 0)
+            {
+                return found
+                    .GroupBy(package => package.Source.Name)
+                    .SelectMany(group => group.Take(SearchLimits.MaxEmptyQueryResultsPerSource))
+                    .ToArray();
+            }
+
             return found.Count > MAX_RESULTS_PER_MANAGER
                 ? found.Take(MAX_RESULTS_PER_MANAGER).ToArray()
                 : found;