Password-Manager-Legacy/Password Manager/PasswordListBox.cs

using System.Collections;

namespace Password_Manager
{
    public delegate string SearchQuery();
    public class PasswordListBox : ListBox
    {
        public event DataRequest? PathRequest;
        public event SearchQuery? SearchQueryRequest;

        public PasswordListBox(DataRequest PathRequest, SearchQuery? SearchQueryRequest = null) : base()
        {
            this.PathRequest = PathRequest;
            this.SearchQueryRequest = SearchQueryRequest;
        }

        public PasswordListBox() : base() { }
        /*do not instantiate this class using this constructor if you want to use the ReloadResults method afterwards.
         Use this so that the MainForm.Designer.cs file doesn't have a stroke due to Event References, then re-instantiate the object
         afterwards using the other constructor*/

        public void ReloadResults(object? sender = null, EventArgs? arg = null)
        {
            DirectoryInfo d;
            FileInfo[] files = new FileInfo[0];
            try
            {
                if (PathRequest != null)
                {
                    d = new DirectoryInfo(PathRequest());
                }
                else
                {
                    throw new InvalidOperationException("You cannot use the ReloadResults method if you instantiated the object using the parameterless constructor");
                }
                files = d.GetFiles("*.gpg");
            }
            catch (ArgumentNullException e)
            {
                MessageBox.Show(e.ToString(), "Error: Invalid path", MessageBoxButtons.OK, MessageBoxIcon.Error);
            }

            List<string> elements = new List<string>();
            for (int i = 0; i < files.Length; i++)
            {
                elements.Add(files[i].Name);
            }

            string[] copy = elements.ToArray();

            string? searchQuery = SearchQueryRequest?.Invoke();
            if (searchQuery != null) //we have a search query
            {
                foreach (string s in copy)
                {
                    if (!s.Contains(searchQuery))
                    {
                        elements.Remove(s);
                    }
                }
            }

            this.DataSource = elements;
            try
            {
                SelectedIndex = 0;
            } catch (ArgumentOutOfRangeException)
            {
                SelectedIndex = -1;
            }
        }
    }
}