namespace PainoBar_Helper
{
    public partial class StationForm : Form
    {
        private readonly PianobarManager _pianobarManager;
        private List<string> _stations;
        private List<string> _filteredStations;
        private bool _stationsLoaded = false;
        private bool _stationEntriesStarted = false;

        public StationForm(PianobarManager pianobarManager)
        {
            InitializeComponent();

            _pianobarManager = pianobarManager;
            _stations = new List<string>();
            _filteredStations = new List<string>();

            InitializeControls();
        }

        #region Initialization

        private void InitializeControls()
        {
            // Uses textBox1 (search box) and lstStations from the Designer
            // Uses btnSelectStation from the Designer

            if (lstStations != null)
            {
                lstStations.DoubleClick += LstStations_DoubleClick;
            }
        }

        protected override void OnShown(EventArgs e)
        {
            base.OnShown(e);

            if (!_stationsLoaded)
                LoadStations();
        }

        private void LoadStations()
        {
            _stations.Clear();
            _filteredStations.Clear();
            _stationsLoaded = false;
            _stationEntriesStarted = false;

            // Subscribe to output to capture station list
            _pianobarManager.OutputReceived += PianobarManager_OutputReceived;

            // Send command to show stations
            try
            {
                _pianobarManager.ShowStations();

                // Show loading message
                if (lstStations != null)
                {
                    lstStations.Items.Clear();
                    lstStations.Items.Add("Loading stations...");
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show($"Failed to load stations:\n{ex.Message}", "Error",
                    MessageBoxButtons.OK, MessageBoxIcon.Error);
            }
        }

        #endregion

        #region Station Loading

        private void PianobarManager_OutputReceived(object? sender, string e)
        {
            var line = StripAnsiCodes(e).Trim();
            if (string.IsNullOrEmpty(line))
                return;

            // Parse station list from Pianobar output
            // Handles formats like: "0) Station", "*0) Station", "  12) Station"
            var match = System.Text.RegularExpressions.Regex.Match(line, @"^\s*\*?\s*(\d+)\)\s*(.+)$");
            if (match.Success)
            {
                _stationEntriesStarted = true;
                string stationName = match.Groups[2].Value.Trim();
                if (!_stations.Contains(stationName))
                {
                    _stations.Add(stationName);
                    if (!IsDisposed && IsHandleCreated)
                        BeginInvoke(() => UpdateStationList());
                }
                return;
            }

            // Detect end of station list only after we started receiving entries
            if (_stationEntriesStarted && line.Contains("Select station:", StringComparison.OrdinalIgnoreCase))
            {
                _stationsLoaded = true;
                _pianobarManager.OutputReceived -= PianobarManager_OutputReceived;
                if (!IsDisposed && IsHandleCreated)
                    BeginInvoke(() => FinalizeStationList());
            }
        }

        private static string StripAnsiCodes(string value)
        {
            return System.Text.RegularExpressions.Regex.Replace(value, @"\x1B\[[0-9;]*[A-Za-z]", string.Empty);
        }

        private void UpdateStationList()
        {
            if (lstStations == null)
                return;

            lstStations.Items.Clear();

            foreach (var station in _filteredStations.Any() ? _filteredStations : _stations)
            {
                lstStations.Items.Add(station);
            }
        }

        private void FinalizeStationList()
        {
            if (lstStations != null)
            {
                if (_stations.Count == 0)
                {
                    lstStations.Items.Clear();
                    lstStations.Items.Add("No stations available");
                }
            }
        }

        #endregion

        #region Search

        // Wire this to textBox1.TextChanged in the Designer
        public void textBox1_TextChanged(object? sender, EventArgs e)
        {
            if (sender is not TextBox txtSearch)
                return;

            string searchText = txtSearch.Text.Trim();

            if (string.IsNullOrWhiteSpace(searchText))
            {
                _filteredStations.Clear();
            }
            else
            {
                _filteredStations = _stations
                    .Where(s => s.IndexOf(searchText, StringComparison.OrdinalIgnoreCase) >= 0)
                    .ToList();
            }

            UpdateStationList();
        }

        #endregion

        #region Station Selection

        // Wire this to btnSelectStation.Click in the Designer
        public void btnSelectStation_Click(object? sender, EventArgs e)
        {
            SelectCurrentStation();
        }

        private void LstStations_DoubleClick(object? sender, EventArgs e)
        {
            SelectCurrentStation();
        }

        private void SelectCurrentStation()
        {
            if (lstStations == null)
                return;

            if (lstStations.SelectedIndex < 0)
            {
                MessageBox.Show("Please select a station.", "No Selection",
                    MessageBoxButtons.OK, MessageBoxIcon.Warning);
                return;
            }

            string selectedStation = lstStations.SelectedItem?.ToString() ?? string.Empty;
            if (string.IsNullOrEmpty(selectedStation))
                return;

            // Find the index in the original station list
            int stationIndex = _stations.IndexOf(selectedStation);
            if (stationIndex < 0)
                return;

            try
            {
                // Send the station index to Pianobar
                // Pianobar expects the station number (0-based index)
                _pianobarManager.SendCommand(stationIndex.ToString());

                DialogResult = DialogResult.OK;
                Close();
            }
            catch (Exception ex)
            {
                MessageBox.Show($"Failed to select station:\n{ex.Message}", "Error",
                    MessageBoxButtons.OK, MessageBoxIcon.Error);
            }
        }

        #endregion

        #region Cancel

        // Wire this to btnCancelStation.Click in the Designer (or Cancel button)
        public void btnCancelStation_Click(object? sender, EventArgs e)
        {
            // Send 'q' to cancel station selection in Pianobar
            try
            {
                _pianobarManager.SendCommand('q');
            }
            catch { }

            DialogResult = DialogResult.Cancel;
            Close();
        }

        #endregion

        #region Cleanup

        protected override void OnFormClosing(FormClosingEventArgs e)
        {
            _pianobarManager.OutputReceived -= PianobarManager_OutputReceived;
            base.OnFormClosing(e);
        }

        #endregion
    }
}