// 
// FileDialog.cs: File system dialogs for open and save
//
// TODO:
//   * Add directory selector
//   * Implement subclasses
//   * Figure out why message text does not show
//   * Remove the extra space when message does not show
//   * Use a line separator to show the file listing, so we can use same colors as the rest
//   * DirListView: Add mouse support

using System.Collections.ObjectModel;
using Terminal.Gui.Resources;

namespace Terminal.Gui;

/// <summary>Determine which <see cref="System.IO"/> type to open.</summary>
public enum OpenMode
{
    /// <summary>Opens only file or files.</summary>
    File,

    /// <summary>Opens only directory or directories.</summary>
    Directory,

    /// <summary>Opens files and directories.</summary>
    Mixed
}

/// <summary>The <see cref="OpenDialog"/>provides an interactive dialog box for users to select files or directories.</summary>
/// <remarks>
///     <para>
///         The open dialog can be used to select files for opening, it can be configured to allow multiple items to be
///         selected (based on the AllowsMultipleSelection) variable and you can control whether this should allow files or
///         directories to be selected.
///     </para>
///     <para>
///         To use, create an instance of <see cref="OpenDialog"/>, and pass it to
///         <see cref="Application.Run(Toplevel, Func{Exception, bool})"/>. This will run the dialog modally, and when this returns,
///         the list of files will be available on the <see cref="FilePaths"/> property.
///     </para>
///     <para>To select more than one file, users can use the spacebar, or control-t.</para>
/// </remarks>
public class OpenDialog : FileDialog
{
    /// <summary>Initializes a new <see cref="OpenDialog"/>.</summary>
    public OpenDialog () { }

    /// <summary>Returns the selected files, or an empty list if nothing has been selected</summary>
    /// <value>The file paths.</value>
    public IReadOnlyList<string> FilePaths =>
        Canceled ? Enumerable.Empty<string> ().ToList ().AsReadOnly () :
        AllowsMultipleSelection ? MultiSelected : new ReadOnlyCollection<string> (new [] { Path });

    /// <inheritdoc/>
    public override OpenMode OpenMode
    {
        get => base.OpenMode;
        set
        {
            base.OpenMode = value;

            Style.OkButtonText = value == OpenMode.File ? Strings.btnOpen :
                                 value == OpenMode.Directory ? Strings.fdSelectFolder : Strings.fdSelectMixed;
        }
    }
}