Add interactive Copilot authentication to splash screen

Tests/Cockpit.UnitTests/Features/TextToSpeech/FakeTextToSpeech.cs

@@ -79,4 +79,5 @@ sealed class MockAppSettingsFeature : IAppSettingsFeature
 	public bool KeepAlive { get; set; }
 	public bool CanvasEnabled { get; set; } = true;
 	public Dictionary<string, Cockpit.Features.SystemMessage.SystemMessageSectionSetting> SystemMessageSectionOverrides { get; set; } = [];
+	public string SessionListGroupBy { get => throw new NotImplementedException(); set => throw new NotImplementedException(); }
 }

Tests/Cockpit.UnitTests/Features/UIState/UIStateFeatureTests.cs

@@ -683,4 +683,5 @@ sealed class MockAppSettings : IAppSettingsFeature
 	public bool KeepAlive { get; set; }
 	public bool CanvasEnabled { get; set; } = true;
 	public Dictionary<string, Cockpit.Features.SystemMessage.SystemMessageSectionSetting> SystemMessageSectionOverrides { get; set; } = [];
+	public string SessionListGroupBy { get => throw new NotImplementedException(); set => throw new NotImplementedException(); }
 }

src/Cockpit/App.xaml.cs

@@ -1,7 +1,10 @@
 using Cockpit.Controls;
+using Cockpit.Features.Auth;
+using Cockpit.Features.Sdk;
 using Cockpit.Features.Sessions;
 using Cockpit.Features.Splash;
 using Cockpit.Features.Theme;
+using Microsoft.Extensions.Logging;
 
 namespace Cockpit;
 
@@ -12,22 +15,31 @@ public partial class App : Application
 	readonly SplashFeature _splashFeature;
 	readonly SessionFeature _sessionFeature;
 	readonly ThemeStateFeature _themeStateFeature;
+	readonly CopilotClientFeature _copilotClientFeature;
+	readonly AuthFeature _authFeature;
+	readonly ILogger<MainPage> _mainPageLogger;
 
 	public App(
 		SplashFeature splashFeature,
 		SessionFeature sessionFeature,
-		ThemeStateFeature themeStateFeature)
+		ThemeStateFeature themeStateFeature,
+		CopilotClientFeature copilotClientFeature,
+		AuthFeature authFeature,
+		ILogger<MainPage> mainPageLogger)
 	{
 		InitializeComponent();
 
 		_splashFeature = splashFeature;
 		_sessionFeature = sessionFeature;
 		_themeStateFeature = themeStateFeature;
+		_copilotClientFeature = copilotClientFeature;
+		_authFeature = authFeature;
+		_mainPageLogger = mainPageLogger;
 	}
 
 	protected override Window CreateWindow(IActivationState? activationState)
 	{
-		_mainWindow = new Window(new MainPage(_splashFeature, _sessionFeature, _themeStateFeature))
+		_mainWindow = new Window(new MainPage(_splashFeature, _sessionFeature, _themeStateFeature, _copilotClientFeature, _authFeature, _mainPageLogger))
 		{
 			Title = "Cockpit",
 			TitleBar = new TitleBar

src/Cockpit/Components/Controls/GitDiff/GitDiffViewer.razor.cs

@@ -27,14 +27,14 @@
 	readonly Dictionary<DiffHunkModel, (int Above, int Below)> _hunkExpansion = [];
 	bool _needsHighlight;
 
 	FileCategory _fileCategory;
 	string? _mediaDataUrl;
 	bool _mediaLoading;
 	bool _mediaTooBig;
 
 	string? _prevDiff;
 	string? _prevFilePath;
 	bool _prevSplitView;
 
 	readonly string _diffInlineId = $"diff-inline-{Guid.NewGuid():N}";
 	readonly string _diffSplitLeftId = $"diff-split-left-{Guid.NewGuid():N}";
@@ -42,17 +42,17 @@
 
 	string FileName => string.IsNullOrEmpty(FilePath) ? string.Empty : Path.GetFileName(FilePath);
 
-	static readonly HashSet<string> ImageExtensions = new(StringComparer.OrdinalIgnoreCase)
+	static readonly HashSet<string> imageExtensions = new(StringComparer.OrdinalIgnoreCase)
 	{
 		".png", ".jpg", ".jpeg", ".gif", ".bmp", ".ico", ".svg", ".webp", ".tiff", ".tif"
 	};
 
-	static readonly HashSet<string> VideoExtensions = new(StringComparer.OrdinalIgnoreCase)
+	static readonly HashSet<string> videoExtensions = new(StringComparer.OrdinalIgnoreCase)
 	{
 		".mp4", ".avi", ".mov", ".wmv", ".flv", ".webm", ".mkv", ".m4v", ".ogv", ".ogg"
 	};
 
-	static readonly HashSet<string> BinaryExtensions = new(StringComparer.OrdinalIgnoreCase)
+	static readonly HashSet<string> binaryExtensions = new(StringComparer.OrdinalIgnoreCase)
 	{
 		".dll", ".exe", ".pdb", ".obj", ".lib", ".bin", ".zip", ".rar", ".7z",
 		".tar", ".gz", ".bz2", ".xz", ".jar", ".war", ".ear", ".class",
@@ -69,9 +69,9 @@
 		}
 
 		string ext = Path.GetExtension(filePath);
-		if(ImageExtensions.Contains(ext)) { return FileCategory.Image; }
-		if(VideoExtensions.Contains(ext)) { return FileCategory.Video; }
-		if(BinaryExtensions.Contains(ext)) { return FileCategory.Binary; }
+		if(imageExtensions.Contains(ext)) { return FileCategory.Image; }
+		if(videoExtensions.Contains(ext)) { return FileCategory.Video; }
+		if(binaryExtensions.Contains(ext)) { return FileCategory.Binary; }
 		return FileCategory.Text;
 	}
 
@@ -387,7 +387,7 @@
 		return result;
 	}
 
 	string? _pendingFilePath;
 
 	protected override void OnParametersSet()
 	{
@@ -430,8 +430,8 @@
 		}
 	}
 
-	const long MaxImageBytes = 20 * 1024 * 1024;
-	const long MaxVideoBytes = 50 * 1024 * 1024;
+	const long maxImageBytes = 20 * 1024 * 1024;
+	const long maxVideoBytes = 50 * 1024 * 1024;
 
 	async Task LoadMediaAsync(string? filePath)
 	{
@@ -442,7 +442,7 @@
 		{
 			try
 			{
-				long maxBytes = _fileCategory == FileCategory.Image ? MaxImageBytes : MaxVideoBytes;
+				long maxBytes = _fileCategory == FileCategory.Image ? maxImageBytes : maxVideoBytes;
 				FileInfo info = new(filePath);
 				if(info.Length <= maxBytes)
 				{

src/Cockpit/Features/Auth/AuthFeature.cs

@@ -0,0 +1,154 @@
+using System.Diagnostics;
+using System.Text.Json;
+using System.Text.RegularExpressions;
+using Microsoft.Extensions.Logging;
+
+namespace Cockpit.Features.Auth;
+
+/// <summary>
+/// Handles the GitHub Copilot CLI login flow (OAuth device flow).
+/// Supports both github.com and GitHub Enterprise hosts.
+/// </summary>
+public partial class AuthFeature
+{
+	readonly ILogger<AuthFeature> _logger;
+
+	public record DeviceFlowInfo(string Url, string Code);
+
+	public AuthFeature(ILogger<AuthFeature> logger)
+	{
+		_logger = logger;
+	}
+
+	/// <summary>
+	/// Spawns <c>copilot login</c> and monitors stdout/stderr for the device flow URL and code.
+	/// Pass <paramref name="host"/> for enterprise accounts (e.g. <c>https://example.ghe.com</c>),
+	/// or <c>null</c> for github.com.
+	/// </summary>
+	public async Task<bool> RunLoginAsync(
+		string? host = null,
+		Action<DeviceFlowInfo>? onDeviceFlow = null,
+		CancellationToken cancellationToken = default)
+	{
+		List<string> args = ["login"];
+		if(!string.IsNullOrWhiteSpace(host) && !host.Equals("https://github.com", StringComparison.OrdinalIgnoreCase))
+		{
+			args.Add("--host");
+			args.Add(host);
+		}
+
+		_logger.LogInformation("Starting copilot login with args: {Args}", string.Join(" ", args));
+
+		ProcessStartInfo psi = new("copilot")
+		{
+			Arguments = string.Join(" ", args),
+			RedirectStandardOutput = true,
+			RedirectStandardError = true,
+			UseShellExecute = false,
+			CreateNoWindow = true
+		};
+
+		using Process? process = Process.Start(psi);
+		if(process is null)
+		{
+			_logger.LogError("Failed to start copilot login process");
+			return false;
+		}
+
+		string? deviceUrl = null;
+		string? deviceCode = null;
+		bool deviceFlowSent = false;
+
+		void ParseOutput(string data)
+		{
+			Match urlMatch = DeviceUrlRegex().Match(data);
+			Match codeMatch = DeviceCodeRegex().Match(data);
+
+			if(urlMatch.Success)
+			{
+				deviceUrl = urlMatch.Groups[1].Value;
+			}
+
+			if(codeMatch.Success)
+			{
+				deviceCode = codeMatch.Groups[1].Value;
+			}
+
+			if(deviceUrl is not null && deviceCode is not null && !deviceFlowSent)
+			{
+				deviceFlowSent = true;
+				_logger.LogInformation("Device flow received - URL: {Url}, Code: {Code}", deviceUrl, deviceCode);
+				onDeviceFlow?.Invoke(new DeviceFlowInfo(deviceUrl, deviceCode));
+			}
+		}
+
+		process.OutputDataReceived += (_, e) =>
+		{
+			if(e.Data is not null)
+			{
+				ParseOutput(e.Data);
+			}
+		};
+
+		process.ErrorDataReceived += (_, e) =>
+		{
+			if(e.Data is not null)
+			{
+				ParseOutput(e.Data);
+			}
+		};
+
+		process.BeginOutputReadLine();
+		process.BeginErrorReadLine();
+
+		await process.WaitForExitAsync(cancellationToken);
+
+		bool success = process.ExitCode == 0;
+		_logger.LogInformation("copilot login exited with code {ExitCode}", process.ExitCode);
+		return success;
+	}
+
+	/// <summary>
+	/// Reads the last-used enterprise host from <c>~/.copilot/config.json</c> for pre-filling the UI.
+	/// Returns <c>null</c> if not found or on any error.
+	/// </summary>
+	public static string? ReadHostFromConfig()
+	{
+		try
+		{
+			string configPath = Path.Combine(
+				Environment.GetFolderPath(Environment.SpecialFolder.UserProfile),
+				".copilot", "config.json");
+
+			if(!File.Exists(configPath))
+			{
+				return null;
+			}
+
+			string json = File.ReadAllText(configPath);
+			using JsonDocument doc = JsonDocument.Parse(json, new JsonDocumentOptions
+			{
+				CommentHandling = JsonCommentHandling.Skip
+			});
+
+			if(doc.RootElement.TryGetProperty("lastLoggedInUser", out JsonElement user) &&
+				user.TryGetProperty("host", out JsonElement host))
+			{
+				return host.GetString();
+			}
+		}
+		catch
+		{
+			// Fall through to default (github.com)
+		}
+
+		return null;
+	}
+
+	// Matches any host's device login URL (github.com or enterprise)
+	[GeneratedRegex(@"(https://\S+/login/device)")]
+	private static partial Regex DeviceUrlRegex();
+
+	[GeneratedRegex(@"code\s+([A-Z0-9]{4}-[A-Z0-9]{4})")]
+	private static partial Regex DeviceCodeRegex();
+}