using System.Windows;
using System.Windows.Input;

namespace Lab8
{
    public partial class MainWindow : Window
    {
        private readonly BusQueueManager _manager = new BusQueueManager();

        private readonly List<string> _commandHistory = new List<string>();
        private int _historyIndex = 0;

        public MainWindow()
        {
            InitializeComponent();
        }

        private void ExecuteButton_Click(object sender, RoutedEventArgs e)
        {
            ExecuteCurrentCommand();
        }

        private void CommandTextBox_PreviewKeyDown(object sender, KeyEventArgs e)
        {
            if (e.Key == Key.Enter)
            {
                ExecuteCurrentCommand();
                e.Handled = true;
                return;
            }

            if (e.Key == Key.Up)
            {
                ShowPreviousCommand();
                e.Handled = true;
                return;
            }

            if (e.Key == Key.Down)
            {
                ShowNextCommand();
                e.Handled = true;
            }
        }

        private void ExecuteCurrentCommand()
        {
            string command = CommandTextBox.Text?.Trim() ?? string.Empty;

            ErrorTextBlock.Text = string.Empty;

            if (string.IsNullOrWhiteSpace(command))
            {
                ErrorTextBlock.Text = "Команда не введена.";
                CommandTextBox.Focus();
                return;
            }

            _commandHistory.Add(command);
            _historyIndex = _commandHistory.Count;

            string result = _manager.ExecuteCommand(command);

            if (result.StartsWith("Ошибка:"))
            {
                ErrorTextBlock.Text = result;
            }
            else
            {
                HistoryListBox.Items.Add($"> {command}");
                HistoryListBox.Items.Add(result);
            }

            UpdateQueueView();
            CommandTextBox.Clear();
            CommandTextBox.Focus();
        }

        private void ShowPreviousCommand()
        {
            if (_commandHistory.Count == 0)
                return;

            if (_historyIndex > 0)
                _historyIndex--;

            CommandTextBox.Text = _commandHistory[_historyIndex];
            CommandTextBox.CaretIndex = CommandTextBox.Text.Length;
        }

        private void ShowNextCommand()
        {
            if (_commandHistory.Count == 0)
                return;

            if (_historyIndex < _commandHistory.Count - 1)
            {
                _historyIndex++;
                CommandTextBox.Text = _commandHistory[_historyIndex];
            }
            else
            {
                _historyIndex = _commandHistory.Count;
                CommandTextBox.Clear();
            }

            CommandTextBox.CaretIndex = CommandTextBox.Text.Length;
        }

        private void UpdateQueueView()
        {
            QueueListBox.Items.Clear();

            foreach (string passenger in _manager.Passengers)
            {
                QueueListBox.Items.Add(passenger);
            }
        }
    }
}