using System;
using System.Collections.Generic;
using System.Linq;
using FireSharp.Interfaces;
using FireSharp.Config;
using FireSharp;
using Newtonsoft.Json;
using System.Configuration;
using Herse.Models;

namespace KaraokePlayer.Classes
{
    public class FirebaseController 
    {
        private IFirebaseConfig config = new FirebaseConfig
        {
            AuthSecret = ConfigurationManager.AppSettings["Firebase.Secret"],
            BasePath = ConfigurationManager.AppSettings["Firebase.Path"]
        };
        private PlayerState _state = PlayerState.Playing;
        private IFirebaseClient _client;
        private ControllerStateChangedEventHandler _stateChanged;
        private ControllerSongChangedEventHandler _songChanged;
        public Settings Settings { get; set; }

        private string SettingsPath
        {
            get { return string.Format("controllers/{0}/player/settings", this.Id); }
        }
        private string QueuePath
        {
            get { return string.Format("controllers/{0}/player/queue", this.Id); }
        }
        private string StatePath
        {
            get { return string.Format("controllers/{0}/player/state/", this.Id); }
        }
        private string CurrentSongPath
        {
            get { return string.Format("controllers/{0}/player/queue/0/", this.Id); }
        }
        private string FavoritesPath
        {
            get { return string.Format("controllers/{0}/favorites/", this.Id); }
        }

        public string Id { get; set; }
        public Song CurrentSong { get; set; }

        public FirebaseController(string clientId, ControllerStateChangedEventHandler stateChanged, ControllerSongChangedEventHandler songChanged)
        {
            Id = clientId;
            _stateChanged = stateChanged;
            _songChanged = songChanged;
            _client = new FirebaseClient(config);
            SetupListener();
            Settings = _client.Get(SettingsPath).ResultAs<Settings>();
        }
        
        private  void SetupListener()
        {
            _client.OnAsync(CurrentSongPath,
                added: (s, args, obj) =>
                {
                    Console.WriteLine("added " + args.Path + "  " + args.Data);
                    CurrentSongDidChange();
                }, 
                removed: (s, args, obj) =>
                {
                    //TODO: the current song was removed from the queue
                }
            );

            _client.OnAsync(StatePath,
                added: (s, args, obj) =>
                {
                    // do we need this? don't think so
                },
                changed: (s, args, obj) =>
                {
                    Console.WriteLine("state changed " + args.Data);
                    PlayerState newstate = (PlayerState)Enum.Parse(typeof(PlayerState), args.Data, true);
                    StateDidChange(newstate);
                },
                removed: null
            );
        }

        /// <summary>
        /// called by the player to end the current song in firebase
        /// </summary>
        public void EndSong()
        {
            SetState(PlayerState.Stopped);
            List<QueueItem> queue = _client.Get(QueuePath).ResultAs<List<QueueItem>>();
            queue.RemoveAt(0);
            _client.Set(QueuePath, queue);
        }

        /// <summary>
        /// called by the player to set the state in firebase
        /// </summary>
        /// <param name="state"></param>
        public void SetState(PlayerState state)
        {
            _state = state;
            _client.SetAsync(StatePath, "Playing");
        }

        /// <summary>
        /// called by firebase to change the current song
        /// </summary>
        private void CurrentSongDidChange()
        {
            var response = _client.Get(CurrentSongPath);
            var item = response.ResultAs<QueueItem>();
            if (item == null) return;
            if (CurrentSong == null || CurrentSong.Path != item.Song.Path)
            {
                CurrentSong = item.Song;
                _songChanged(new ControllerSongChangedEventArgs(item.Song));
                UpdateFavorites(item.Song);
            }
        }

        /// <summary>
        /// called by firebase to change the current state
        /// </summary>
        /// <param name="newstate"></param>
        private void StateDidChange(PlayerState newstate)
        {
            if (newstate == _state) return; 
            _state = newstate;
            _stateChanged(new ControllerStateChangedEventArgs(newstate));
        }

        private void UpdateFavorites(Song song)
        {
            //get favorites
            FavoriteSong favorite = null;
            List<FavoriteSong> favorites = _client.Get(FavoritesPath).ResultAs<List<FavoriteSong>>();
            if (favorites == null) favorites = new List<FavoriteSong>();

            //unique song is based on the path
            favorite = favorites.SingleOrDefault(f => f.Path == song.Path);
            if (favorite == null)
            {
                favorite = new FavoriteSong();
                favorite.Artist = song.Artist;
                favorite.Title = song.Title;
                favorite.Genre = song.Genre;
                favorite.Path = song.Path;
                favorite.Year = song.Year;
                favorite.Count = 1;
                favorites.Add(favorite);
            }
            else {
                favorite.Count += 1;
            }

            //take the top 100 songs                
            var top100 = favorites.OrderByDescending(f => f.Count).Take(100);
            _client.Set(FavoritesPath, top100);

        }
    }
}