using Avalonia.Controls;
using Avalonia.Interactivity;
using Avalonia.Platform.Storage;
using Nonemm.Core;

namespace Nonemm.App.Dialogs;

/// The function key messages as the text of an N1MM `.mc` file. Editing them as
/// the file rather than as twelve boxes is what makes import and export the
/// same thing as what is on the screen.
///
/// It closes with the text, or with null when nothing is to be changed.
public sealed partial class MessagesDialog : Window
{
    private static readonly FilePickerFileType MessageFiles = new("Function key files")
    {
        Patterns = ["*.mc"],
    };

    private readonly ModeCategory mode;

    public MessagesDialog(ModeCategory mode, string text, string what = "Function key messages")
    {
        this.mode = mode;
        InitializeComponent();
        Title = $"{what} — {(mode == ModeCategory.Phone ? "phone" : "CW")}";
        TextArea.Text = text.Trim().Length > 0 ? text : Messages.DefaultFor(mode);
    }

    private async void OnImport(object? sender, RoutedEventArgs e)
    {
        IReadOnlyList<IStorageFile> files = await StorageProvider.OpenFilePickerAsync(
            new FilePickerOpenOptions
            {
                Title = "Import a function key file",
                AllowMultiple = false,
                FileTypeFilter = [MessageFiles],
            });
        if (files.FirstOrDefault()?.TryGetLocalPath() is not { } path)
        {
            return;
        }
        try
        {
            TextArea.Text = await File.ReadAllTextAsync(path);
        }
        catch (Exception error) when (error is IOException or UnauthorizedAccessException)
        {
            TextArea.Text = $"# {path} could not be read: {error.Message}\n{TextArea.Text}";
        }
    }

    private async void OnExport(object? sender, RoutedEventArgs e)
    {
        IStorageFile? file = await StorageProvider.SaveFilePickerAsync(new FilePickerSaveOptions
        {
            Title = "Export the function key file",
            SuggestedFileName = mode == ModeCategory.Phone ? "phone.mc" : "cw.mc",
            DefaultExtension = "mc",
            FileTypeChoices = [MessageFiles],
        });
        if (file?.TryGetLocalPath() is not { } path)
        {
            return;
        }
        try
        {
            await File.WriteAllTextAsync(path, TextArea.Text ?? "");
        }
        catch (Exception error) when (error is IOException or UnauthorizedAccessException)
        {
            TextArea.Text = $"# {path} could not be written: {error.Message}\n{TextArea.Text}";
        }
    }

    private void OnDefaults(object? sender, RoutedEventArgs e) =>
        TextArea.Text = Messages.DefaultFor(mode);

    private void OnSave(object? sender, RoutedEventArgs e) => Close(TextArea.Text ?? "");

    private void OnCancel(object? sender, RoutedEventArgs e) => Close(null);
}