Improve desktop browser launch flow

Adds readiness probing, app-mode Edge/Chrome launch support, browser process tracking, and conditional HTTPS redirection for desktop hosting.

Controllers/DesktopHostController.cs

@@ -0,0 +1,14 @@
+using Microsoft.AspNetCore.Mvc;
+
+namespace AVSCartonShipmentVerifier.Controllers;
+
+/// <summary>
+/// Lightweight endpoints for desktop host startup (no database or dashboard work).
+/// </summary>
+[ApiController]
+public sealed class DesktopHostController : ControllerBase
+{
+    [HttpGet("/health")]
+    [HttpGet("/api/desktop-host/ready")]
+    public IActionResult Ready() => Ok(new { ready = true });
+}

Hosting/DesktopBrowserLauncher.cs

@@ -0,0 +1,115 @@
+using System.Diagnostics;
+using System.Text;
+
+namespace AVSCartonShipmentVerifier.Hosting;
+
+internal static class DesktopBrowserLauncher
+{
+    internal sealed record LaunchResult(Process? TrackedProcess, bool UsedAppMode);
+
+    public static LaunchResult TryLaunch(string url, bool preferAppMode, string? userDataDir)
+    {
+        if (preferAppMode && OperatingSystem.IsWindows())
+        {
+            var profileDir = ResolveProfileDirectory(userDataDir);
+
+            foreach (var (fileName, arguments) in GetAppModeCandidates(url, profileDir))
+            {
+                if (!File.Exists(fileName))
+                {
+                    continue;
+                }
+
+                try
+                {
+                    var process = Process.Start(new ProcessStartInfo
+                    {
+                        FileName = fileName,
+                        Arguments = arguments,
+                        UseShellExecute = false
+                    });
+
+                    if (process is not null)
+                    {
+                        return new LaunchResult(process, UsedAppMode: true);
+                    }
+                }
+                catch
+                {
+                    // Try next browser.
+                }
+            }
+        }
+
+        try
+        {
+            if (OperatingSystem.IsWindows())
+            {
+                Process.Start(new ProcessStartInfo(url) { UseShellExecute = true });
+            }
+            else if (OperatingSystem.IsMacOS())
+            {
+                Process.Start("open", url);
+            }
+            else
+            {
+                Process.Start(new ProcessStartInfo("xdg-open", url) { UseShellExecute = true });
+            }
+
+            return new LaunchResult(null, UsedAppMode: false);
+        }
+        catch
+        {
+            return new LaunchResult(null, UsedAppMode: false);
+        }
+    }
+
+    private static string? ResolveProfileDirectory(string? userDataDir)
+    {
+        if (string.IsNullOrWhiteSpace(userDataDir))
+        {
+            return null;
+        }
+
+        var profileDir = userDataDir.Trim();
+        Directory.CreateDirectory(profileDir);
+        return profileDir;
+    }
+
+    private static IEnumerable<(string FileName, string Arguments)> GetAppModeCandidates(string url, string? profileDir)
+    {
+        var builder = new StringBuilder();
+        builder.Append("--app=").Append(url);
+        builder.Append(" --new-window");
+
+        if (!string.IsNullOrWhiteSpace(profileDir))
+        {
+            var escapedProfile = profileDir.Replace("\"", "\\\"", StringComparison.Ordinal);
+            builder.Append(" --user-data-dir=\"").Append(escapedProfile).Append('"');
+        }
+
+        var appArgs = builder.ToString();
+
+        foreach (var edgePath in EdgePaths())
+        {
+            yield return (edgePath, appArgs);
+        }
+
+        foreach (var chromePath in ChromePaths())
+        {
+            yield return (chromePath, appArgs);
+        }
+    }
+
+    private static IEnumerable<string> EdgePaths()
+    {
+        yield return Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.ProgramFilesX86), "Microsoft", "Edge", "Application", "msedge.exe");
+        yield return Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.ProgramFiles), "Microsoft", "Edge", "Application", "msedge.exe");
+    }
+
+    private static IEnumerable<string> ChromePaths()
+    {
+        yield return Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.ProgramFiles), "Google", "Chrome", "Application", "chrome.exe");
+        yield return Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.ProgramFilesX86), "Google", "Chrome", "Application", "chrome.exe");
+    }
+}

Hosting/KestrelConfiguration.cs

@@ -0,0 +1,20 @@
+namespace AVSCartonShipmentVerifier.Hosting;
+
+internal static class KestrelConfiguration
+{
+    public static bool HasHttpsEndpoint(IConfiguration configuration)
+    {
+        var endpoints = configuration.GetSection("Kestrel:Endpoints").GetChildren();
+        foreach (var endpoint in endpoints)
+        {
+            var url = endpoint["Url"];
+            if (!string.IsNullOrWhiteSpace(url)
+                && url.StartsWith("https://", StringComparison.OrdinalIgnoreCase))
+            {
+                return true;
+            }
+        }
+
+        return false;
+    }
+}

Hosting/LaunchBrowserHostedService.cs

@@ -1,31 +1,37 @@
-using System.Diagnostics;
+using System.Net.Http;
 using AVSCartonShipmentVerifier.Configuration;
 using Microsoft.AspNetCore.Hosting.Server;
 using Microsoft.AspNetCore.Hosting.Server.Features;
-using Microsoft.Extensions.Hosting;
 using Microsoft.Extensions.Options;
 
 namespace AVSCartonShipmentVerifier.Hosting;
 
 /// <summary>
 /// Opens the default browser once the web server has started (Windows desktop-style launch).
+/// Stops the host when the browser window closes when <see cref="DesktopHostOptions.ExitWhenBrowserCloses"/> is enabled.
 /// </summary>
 internal sealed class LaunchBrowserHostedService : IHostedService
 {
+    private const string DefaultBrowserUrl = "http://127.0.0.1:5000";
+    private const string ReadinessPath = "/health";
+
     private readonly IHostApplicationLifetime _lifetime;
     private readonly IOptions<DesktopHostOptions> _options;
     private readonly IServer _server;
+    private readonly DesktopShutdownService _shutdown;
     private readonly ILogger<LaunchBrowserHostedService> _logger;
 
     public LaunchBrowserHostedService(
         IServer server,
         IHostApplicationLifetime lifetime,
         IOptions<DesktopHostOptions> options,
+        DesktopShutdownService shutdown,
         ILogger<LaunchBrowserHostedService> logger)
     {
         _server = server;
         _lifetime = lifetime;
         _options = options;
+        _shutdown = shutdown;
         _logger = logger;
     }
 
@@ -33,13 +39,15 @@ internal sealed class LaunchBrowserHostedService : IHostedService
     {
         var opts = _options.Value;
         if (!opts.LaunchBrowser)
+        {
             return Task.CompletedTask;
+        }
 
-        _lifetime.ApplicationStarted.Register(OpenBrowser);
+        _lifetime.ApplicationStarted.Register(() => _ = OpenBrowserAsync());
         return Task.CompletedTask;
     }
 
-    private void OpenBrowser()
+    private async Task OpenBrowserAsync()
     {
         try
         {
@@ -50,17 +58,34 @@ internal sealed class LaunchBrowserHostedService : IHostedService
                 return;
             }
 
-            if (OperatingSystem.IsWindows())
+            if (!await WaitForServerReadyAsync(url).ConfigureAwait(false))
             {
-                Process.Start(new ProcessStartInfo(url) { UseShellExecute = true });
+                _logger.LogWarning(
+                    "Server did not respond on readiness endpoint before opening the browser at {Url}.",
+                    url);
             }
-            else if (OperatingSystem.IsMacOS())
+
+            var opts = _options.Value;
+            var preferAppMode = opts.PreferAppModeBrowser && opts.ExitWhenBrowserCloses;
+            var launch = DesktopBrowserLauncher.TryLaunch(url, preferAppMode, opts.BrowserUserDataDir);
+            var minimumLifetime = TimeSpan.FromSeconds(Math.Max(1, opts.MinimumBrowserProcessLifetimeSeconds));
+
+            if (opts.ExitWhenBrowserCloses && launch.TrackedProcess is not null)
             {
-                Process.Start("open", url);
+                _shutdown.WatchBrowserProcess(launch.TrackedProcess, minimumLifetime);
+                _logger.LogInformation(
+                    "Opened browser in app mode (PID {ProcessId}) at {Url} using profile {ProfileDir}. Application will exit when the window is closed.",
+                    launch.TrackedProcess.Id,
+                    url,
+                    opts.BrowserUserDataDir);
+                return;
             }
-            else
+
+            if (opts.ExitWhenBrowserCloses)
             {
-                Process.Start(new ProcessStartInfo("xdg-open", url) { UseShellExecute = true });
+                _logger.LogInformation(
+                    "Opened default browser at {Url}. Application will exit shortly after the app tab/window is closed.",
+                    url);
             }
         }
         catch (Exception ex)
@@ -69,19 +94,64 @@ internal sealed class LaunchBrowserHostedService : IHostedService
         }
     }
 
-    private string? ResolveUrl()
+    private static async Task<bool> WaitForServerReadyAsync(string dashboardBaseUrl)
+    {
+        using var client = new HttpClient { Timeout = TimeSpan.FromSeconds(2) };
+        var probeUrl = dashboardBaseUrl.TrimEnd('/') + ReadinessPath;
+
+        for (var attempt = 0; attempt < 50; attempt++)
+        {
+            try
+            {
+                using var response = await client.GetAsync(probeUrl).ConfigureAwait(false);
+                if (response.IsSuccessStatusCode)
+                {
+                    return true;
+                }
+            }
+            catch
+            {
+                // Server not ready yet.
+            }
+
+            await Task.Delay(100).ConfigureAwait(false);
+        }
+
+        return false;
+    }
+
+    private string ResolveUrl()
     {
         var configured = _options.Value.BrowserUrl;
         if (!string.IsNullOrWhiteSpace(configured))
-            return configured;
+        {
+            return configured.Trim();
+        }
 
         var addresses = _server.Features.Get<IServerAddressesFeature>()?.Addresses;
-        if (addresses is null || addresses.Count == 0)
+        if (addresses is { Count: > 0 })
-            return null;
+        {
+            var address = addresses.FirstOrDefault(static a => a.StartsWith("http://", StringComparison.OrdinalIgnoreCase))
+                ?? addresses.FirstOrDefault(static a => a.StartsWith("https://", StringComparison.OrdinalIgnoreCase))
+                ?? addresses.First();
 
-        return addresses.FirstOrDefault(static a => a.StartsWith("http://", StringComparison.OrdinalIgnoreCase))
+            if (!string.IsNullOrWhiteSpace(address))
-            ?? addresses.FirstOrDefault(static a => a.StartsWith("https://", StringComparison.OrdinalIgnoreCase))
+            {
-            ?? addresses.FirstOrDefault();
+                return NormalizeLoopbackAddress(address);
+            }
+        }
+
+        return DefaultBrowserUrl;
+    }
+
+    private static string NormalizeLoopbackAddress(string address)
+    {
+        if (address.Contains("://localhost", StringComparison.OrdinalIgnoreCase))
+        {
+            return address.Replace("://localhost", "://127.0.0.1", StringComparison.OrdinalIgnoreCase);
+        }
+
+        return address;
     }
 
     public Task StopAsync(CancellationToken cancellationToken) => Task.CompletedTask;