WindowAttachmentHelper.cs

using System.Diagnostics;
using System.Runtime.InteropServices;
using System.Text;

namespace NoteUI;

/// <summary>
/// Helper to enumerate visible windows for the "Attach to program" picker.
/// </summary>
public static class WindowAttachmentHelper
{
    public record WindowInfo(string ProcessName, string Title);
    public record WebTabInfo(string ProcessName, string Title);

    private static readonly HashSet<string> BrowserProcesses = new(StringComparer.OrdinalIgnoreCase)
    {
        "chrome",
        "msedge",
        "firefox",
        "brave",
        "opera",
        "arc",
        "vivaldi",
        "chromium",
        "iexplore",
    };

    public static List<WindowInfo> GetVisibleWindows()
    {
        var results = new List<WindowInfo>();
        var seen = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
        var currentPid = Environment.ProcessId;

        EnumWindows((hwnd, _) =>
        {
            if (!IsWindowVisible(hwnd)) return true;

            var sb = new StringBuilder(256);
            GetWindowText(hwnd, sb, sb.Capacity);
            var title = sb.ToString();
            if (string.IsNullOrWhiteSpace(title)) return true;

            GetWindowThreadProcessId(hwnd, out var pid);
            if (pid == 0 || pid == currentPid) return true;

            try
            {
                var proc = Process.GetProcessById((int)pid);
                var name = proc.ProcessName;

                // Skip system processes
                if (name is "explorer" or "SearchHost" or "ShellExperienceHost"
                    or "StartMenuExperienceHost" or "TextInputHost" or "SystemSettings")
                    return true;

                // Deduplicate by process name (keep first = most relevant window)
                if (seen.Add(name))
                    results.Add(new WindowInfo(name, title.Length > 60 ? title[..57] + "..." : title));
            }
            catch { }

            return true;
        }, IntPtr.Zero);

        return results.OrderBy(w => w.ProcessName, StringComparer.OrdinalIgnoreCase).ToList();
    }

    public static List<WebTabInfo> GetVisibleWebTabs()
    {
        var results = new List<WebTabInfo>();
        var seen = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
        var currentPid = Environment.ProcessId;

        EnumWindows((hwnd, _) =>
        {
            if (!IsWindowVisible(hwnd)) return true;

            var sb = new StringBuilder(512);
            GetWindowText(hwnd, sb, sb.Capacity);
            var title = NormalizeBrowserTitle(sb.ToString());
            if (string.IsNullOrWhiteSpace(title)) return true;

            GetWindowThreadProcessId(hwnd, out var pid);
            if (pid == 0 || pid == currentPid) return true;

            try
            {
                var proc = Process.GetProcessById((int)pid);
                var name = proc.ProcessName;
                if (!BrowserProcesses.Contains(name))
                    return true;

                var dedupKey = $"{name}|{title}";
                if (seen.Add(dedupKey))
                    results.Add(new WebTabInfo(name, title));
            }
            catch { }

            return true;
        }, IntPtr.Zero);

        return results
            .OrderBy(w => w.ProcessName, StringComparer.OrdinalIgnoreCase)
            .ThenBy(w => w.Title, StringComparer.OrdinalIgnoreCase)
            .ToList();
    }

    private static string NormalizeBrowserTitle(string title)
    {
        var normalized = title.Trim();
        if (normalized.Length == 0)
            return normalized;

        string[] suffixes =
        [
            " - Google Chrome",
            " - Microsoft Edge",
            " - Mozilla Firefox",
            " - Brave",
            " - Opera",
            " - Arc",
            " - Vivaldi",
            " - Chromium",
            " - Internet Explorer"
        ];

        foreach (var suffix in suffixes)
        {
            if (normalized.EndsWith(suffix, StringComparison.OrdinalIgnoreCase))
                return normalized[..^suffix.Length].Trim();
        }

        return normalized;
    }

    private delegate bool EnumWindowsProc(IntPtr hWnd, IntPtr lParam);

    [DllImport("user32.dll")]
    private static extern bool EnumWindows(EnumWindowsProc lpEnumFunc, IntPtr lParam);

    [DllImport("user32.dll")]
    private static extern bool IsWindowVisible(IntPtr hWnd);

    [DllImport("user32.dll", CharSet = CharSet.Unicode)]
    private static extern int GetWindowText(IntPtr hWnd, StringBuilder lpString, int nMaxCount);

    [DllImport("user32.dll")]
    private static extern uint GetWindowThreadProcessId(IntPtr hWnd, out uint processId);
}