Artemis/src/Artemis.UI.Shared/Services/Builders/OpenFileDialogBuilder.cs

using System;
using System.Collections.Generic;
using System.Threading.Tasks;
using Avalonia.Controls;

namespace Artemis.UI.Shared.Services.Builders
{
    /// <summary>
    ///     Represents a builder that can create a <see cref="OpenFileDialog" />.
    /// </summary>
    public class OpenFileDialogBuilder
    {
        private readonly OpenFileDialog _openFileDialog;
        private readonly Window _parent;

        /// <summary>
        /// Creates a new instance of the <see cref="OpenFileDialogBuilder"/> class.
        /// </summary>
        /// <param name="parent">The parent window that will host the dialog.</param>
        public OpenFileDialogBuilder(Window parent)
        {
            _parent = parent;
            _openFileDialog = new OpenFileDialog();
        }

        /// <summary>
        ///     Indicate that the user can select multiple files.
        /// </summary>
        public OpenFileDialogBuilder WithAllowMultiple()
        {
            _openFileDialog.AllowMultiple = true;
            return this;
        }

        /// <summary>
        ///     Set the title of the dialog
        /// </summary>
        public OpenFileDialogBuilder WithTitle(string? title)
        {
            _openFileDialog.Title = title;
            return this;
        }

        /// <summary>
        ///     Set the initial directory of the dialog
        /// </summary>
        public OpenFileDialogBuilder WithDirectory(string? directory)
        {
            _openFileDialog.Directory = directory;
            return this;
        }

        /// <summary>
        ///     Set the initial file name of the dialog
        /// </summary>
        public OpenFileDialogBuilder WithInitialFileName(string? initialFileName)
        {
            _openFileDialog.InitialFileName = initialFileName;
            return this;
        }

        /// <summary>
        ///     Add a filter to the dialog
        /// </summary>
        public OpenFileDialogBuilder HavingFilter(Action<FileDialogFilterBuilder> configure)
        {
            FileDialogFilterBuilder builder = new();
            configure(builder);
            
            _openFileDialog.Filters ??= new List<FileDialogFilter>();
            _openFileDialog.Filters.Add(builder.Build());

            return this;
        }

        /// <summary>
        ///     Asynchronously shows the file dialog.
        /// </summary>
        /// <returns>
        ///     A task that on completion returns an array containing the full path to the selected
        ///     files, or null if the dialog was canceled.
        /// </returns>
        public async Task<string[]?> ShowAsync()
        {
            return await _openFileDialog.ShowAsync(_parent);
        }
    }
}