using System.Net;
using System.Text;
using System.Text.Json;

namespace PainoBar_Helper
{
    /// <summary>
    /// Manages various output mechanisms for song metadata
    /// </summary>
    public class OutputManager : IDisposable
    {
        private readonly ProfileSettings _settings;
        private HttpListener? _webServer;
        private string? _currentMetadataJson;
        private bool _isActive;

        public OutputManager(ProfileSettings settings)
        {
            _settings = settings;
        }

        public event EventHandler? ActiveStateChanged;

        public bool IsActive
        {
            get => _isActive;
            private set
            {
                if (_isActive != value)
                {
                    _isActive = value;
                    ActiveStateChanged?.Invoke(this, EventArgs.Empty);
                }
            }
        }

        public void Start()
        {
            Stop();

            if (_settings.EnableWebServer)
                StartWebServer();

            UpdateActiveState();
        }

        public void Stop()
        {
            StopWebServer();
            UpdateActiveState();
        }

        public void UpdateSongMetadata(SongChangedEventArgs metadata)
        {
            var metadataObj = new
            {
                title = metadata.Title,
                artist = metadata.Artist,
                album = metadata.Album,
                albumArtUrl = metadata.AlbumArtUrl,
                timestamp = DateTime.Now
            };

            _currentMetadataJson = JsonSerializer.Serialize(metadataObj, new JsonSerializerOptions { WriteIndented = true });

            if (_settings.EnableTextFile && !string.IsNullOrEmpty(_settings.TextFilePath))
                WriteTextFile(metadata);

            if (_settings.EnableToastNotifications)
                ShowToastNotification(metadata);

            if (_settings.EnableSMTC)
                UpdateSMTC(metadata);
        }

        private void WriteTextFile(SongChangedEventArgs metadata)
        {
            try
            {
                var dir = Path.GetDirectoryName(_settings.TextFilePath);
                if (!string.IsNullOrEmpty(dir))
                    Directory.CreateDirectory(dir);

                var sb = new StringBuilder();
                sb.AppendLine($"Title: {metadata.Title}");
                sb.AppendLine($"Artist: {metadata.Artist}");
                sb.AppendLine($"Album: {metadata.Album}");
                sb.AppendLine($"Album Art URL: {metadata.AlbumArtUrl}");
                sb.AppendLine($"Updated: {DateTime.Now:yyyy-MM-dd HH:mm:ss}");

                File.WriteAllText(_settings.TextFilePath, sb.ToString());
            }
            catch
            {
                // Silently fail
            }
        }

        private void StartWebServer()
        {
            try
            {
                _webServer = new HttpListener();
                _webServer.Prefixes.Add($"http://localhost:{_settings.WebServerPort}/");
                _webServer.Start();

                Task.Run(() => WebServerLoop());
            }
            catch
            {
                _webServer = null;
            }
        }

        private void StopWebServer()
        {
            if (_webServer != null)
            {
                try
                {
                    _webServer.Stop();
                    _webServer.Close();
                }
                catch { }
                finally
                {
                    _webServer = null;
                }
            }
        }

        private async void WebServerLoop()
        {
            while (_webServer != null && _webServer.IsListening)
            {
                try
                {
                    var context = await _webServer.GetContextAsync();
                    HandleWebRequest(context);
                }
                catch
                {
                    break;
                }
            }
        }

        private void HandleWebRequest(HttpListenerContext context)
        {
            try
            {
                var response = context.Response;
                response.ContentType = "application/json";
                response.ContentEncoding = Encoding.UTF8;

                string responseData = _currentMetadataJson ?? "{}";
                byte[] buffer = Encoding.UTF8.GetBytes(responseData);

                response.ContentLength64 = buffer.Length;
                response.OutputStream.Write(buffer, 0, buffer.Length);
                response.OutputStream.Close();
            }
            catch { }
        }

        private void ShowToastNotification(SongChangedEventArgs metadata)
        {
            // Windows Toast Notification implementation placeholder
            // In a full implementation, you would use Windows.UI.Notifications
            // For now, this is a placeholder that can be extended
            try
            {
                // TODO: Implement using Windows.UI.Notifications ToastNotificationManager
                // This requires adding Windows SDK references
            }
            catch { }
        }

        private void UpdateSMTC(SongChangedEventArgs metadata)
        {
            // Windows System Media Transport Controls implementation placeholder
            // In a full implementation, you would use Windows.Media.SystemMediaTransportControls
            // For now, this is a placeholder that can be extended
            try
            {
                // TODO: Implement using Windows.Media.SystemMediaTransportControls
                // This requires adding Windows SDK references
            }
            catch { }
        }

        private void UpdateActiveState()
        {
            bool anyActive = false;

            if (_settings.EnableTextFile && !string.IsNullOrEmpty(_settings.TextFilePath))
                anyActive = true;

            if (_settings.EnableWebServer && _webServer != null && _webServer.IsListening)
                anyActive = true;

            if (_settings.EnableToastNotifications)
                anyActive = true;

            if (_settings.EnableSMTC)
                anyActive = true;

            IsActive = anyActive;
        }

        public void Dispose()
        {
            Stop();
        }
    }
}