using AngleSharp.Parser.Html;
using FireSharp.Config;
using FireSharp.Interfaces;
using Herse.Models;
using Newtonsoft.Json;
using System;
using System.Collections.Generic;
using System.Configuration;
using System.IO;
using System.Linq;
using System.Net;
using System.Text;
using System.Threading.Tasks;

namespace BillboardPlaylistUpdater
{
    class Program
    {

        static void Main(string[] args)
        {
            IFirebaseConfig config = new FirebaseConfig
            {
                AuthSecret = ConfigurationManager.AppSettings["Firebase.Secret"],
                BasePath = ConfigurationManager.AppSettings["Firebase.Path"]
            };
            FireSharp.FirebaseClient client = new FireSharp.FirebaseClient(config);
            string firepath = "SongList";
            Console.WriteLine("Loading current library");
            List<SongList> songList = client.Get(firepath).ResultAs<List<SongList>>();
            if (songList != null)
                Console.WriteLine(string.Format("{0} songList loaded", songList.Count));
            else
                songList = new List<SongList>();


            SongList pop = Download("Pop-Songs","http://www.billboard.com/charts/pop-songs");
            SongList rock = Download("Rock-Songs","http://www.billboard.com/charts/rock-songs");
            SongList country = Download("Country-Songs", "http://www.billboard.com/charts/country-songs");
            SongList hiphop = Download("R-B-Hip-Hop-Songs", "http://www.billboard.com/charts/r-b-hip-hop-songs");

            List<SongList> localSongList = new List<SongList>();
            localSongList.Add(pop);
            localSongList.Add(rock);
            localSongList.Add(country);
            localSongList.Add(hiphop);

            foreach (SongList sl in localSongList)
            {
                try
                {
                    Console.WriteLine(string.Format("Checking for {0}", sl.Title));
                    var found = songList.Where(s => s.Title.ToLower() == sl.Title.ToLower());
                    if(found != null)
                    {
                        var items = found.ToList();
                        foreach (var item in items)
                        {
                            songList.Remove(item);  
                        }
                    }
                    songList.Add(sl);
                    
                }
                catch (Exception ex)
                {
                    Console.WriteLine(ex.Message);
                }
            }
            client.Set(firepath, songList);

        }

        static SongList Download(string listName, string url)
        {
            DateTime now = DateTime.Now;
            string title = now.Year + " - " + listName;

            Console.WriteLine("Downloading " + title);

            string html = DownloadHtml(url);

            SongList list = null;
            List<SongListSong> songs = Parse(title, html);
            if (songs != null)
            {
                list = new SongList();
                list.Title = title;
                list.Songs = songs;
            }
            return list;
        }

        static List<SongListSong> Parse(string name, string html)
        {
            List<SongListSong> songs = null;
            var parser = new HtmlParser();
            var document = parser.Parse(html);
            var articles = document.QuerySelectorAll("article.chart-row");
            if(articles.Count() > 0) {
                Console.WriteLine("Found " + articles.Count() + " Songs");
                songs = new List<SongListSong>();
            }
            var i = 1;
            foreach (var article in articles)
            {
                var title = article.QuerySelector("h2.chart-row__song");
                var artist = article.QuerySelector("a.chart-row__artist");
                var position = article.QuerySelector("span.chart-row__current-week");
                if (artist == null)
                {
                    artist = article.QuerySelector("h3.chart-row__artist");
                }
                if(title != null && artist != null && position != null)
                {
                    SongListSong song = new SongListSong();
                    song.Artist = artist.InnerHtml.Trim().Replace("\n","");
                    song.Title = title.InnerHtml.Trim().Replace("\n","");
                    song.Position = Int32.Parse(position.InnerHtml.Trim());
                    songs.Add(song);
                } else
                {
                    Console.WriteLine("couldn't find objects in " + title + " for Song #" + i);
                }
                i++;
            }
            Console.Write("Parsed " + songs.Count() + " Songs");
            return songs;
        }

        static string DownloadHtml(string url)
        {
            string data = null;
            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
            HttpWebResponse response = (HttpWebResponse)request.GetResponse();
            if(response.StatusCode == HttpStatusCode.OK)
            {
                Stream receiveStream = response.GetResponseStream();
                StreamReader readStream = null;
                if(response.CharacterSet == null)
                {
                    readStream = new StreamReader(receiveStream);
                }else
                {
                    readStream = new StreamReader(receiveStream, Encoding.GetEncoding(response.CharacterSet));
                }
                data = readStream.ReadToEnd();

                response.Close();
                readStream.Close();
            }
            return data;
        }        
    }
}