using Microsoft.Extensions.Logging;
using MySql.Data.MySqlClient;
using Roadie.Library;
using Roadie.Library.Caching;
using Roadie.Library.Configuration;
using Roadie.Library.Encoding;
using Roadie.Library.Models.Statistics;
using Roadie.Library.Utility;
using System;
using System.Diagnostics;
using System.Threading.Tasks;
using data = Roadie.Library.Data;

namespace Roadie.Api.Services
{
    public class StatisticsService : ServiceBase, IStatisticsService
    {
        public StatisticsService(IRoadieSettings configuration,
                             IHttpEncoder httpEncoder,
                             IHttpContext httpContext,
                             data.IRoadieDbContext context,
                             ICacheManager cacheManager,
                             ILogger<StatisticsService> logger)
            : base(configuration, httpEncoder, context, cacheManager, logger, httpContext)
        {
        }

        public async Task<OperationResult<LibraryStats>> LibraryStatistics()
        {
            LibraryStats result = null;
            var sw = new Stopwatch();
            sw.Start();
            using (var conn = new MySqlConnection(this.Configuration.ConnectionString))
            {
                conn.Open();
                var sql = @"SELECT rm.releaseMediaCount AS releaseMediaCount, COUNT(r.roadieId) AS releaseCount,
                                ts.trackCount, ts.trackDuration as TotalTrackDuration, ts.trackSize as TotalTrackSize, ac.artistCount, lc.labelCount, pc.playedCount, uc.userCount, cc.collectionCount, pl.playlistCount
                            FROM `release` r
                            INNER JOIN (
	                            SELECT COUNT(1) AS trackCount, SUM(t.duration) AS trackDuration, SUM(t.fileSize) AS trackSize
	                            FROM `track` t
	                            JOIN `releasemedia` rm ON rm.id = t.releaseMediaId
	                            JOIN `release` r ON r.id = rm.releaseId
	                            JOIN `artist` a ON a.id = r.artistId
	                            WHERE t.hash IS NOT NULL) ts
                            INNER JOIN (
	                            SELECT COUNT(1) AS artistCount
	                            FROM `artist`) ac
                            INNER JOIN (
	                            SELECT COUNT(1) AS labelCount
	                            FROM `label`) lc
                            INNER JOIN (
	                            SELECT SUM(playedCount) as playedCount
	                            FROM `usertrack`) pc
                            INNER JOIN (
	                            SELECT COUNT(1) as releaseMediaCount
	                            FROM `releasemedia`) rm
                            INNER JOIN (
	                            SELECT COUNT(1) as userCount
	                            FROM `user`) uc
                            INNER JOIN (
	                            SELECT COUNT(1) as collectionCount
	                            FROM `collection`) cc
                            INNER JOIN (
	                            SELECT COUNT(1) as playlistCount
	                            FROM `playlist`) pl;";
                using (var cmd = new MySqlCommand(sql, conn))
                {
                    try
                    {
                        using (var rdr = await cmd.ExecuteReaderAsync())
                        {
                            if (rdr.HasRows)
                            {
                                while (rdr.Read())
                                {
                                    result = new LibraryStats
                                    {
                                        UserCount = SafeParser.ToNumber<int?>(rdr["UserCount"]),
                                        CollectionCount = SafeParser.ToNumber<int?>(rdr["CollectionCount"]),
                                        PlaylistCount = SafeParser.ToNumber<int?>(rdr["PlaylistCount"]),
                                        ArtistCount = SafeParser.ToNumber<int?>(rdr["ArtistCount"]),
                                        LabelCount = SafeParser.ToNumber<int?>(rdr["LabelCount"]),
                                        ReleaseCount = SafeParser.ToNumber<int?>(rdr["ReleaseCount"]),
                                        ReleaseMediaCount = SafeParser.ToNumber<int?>(rdr["ReleaseMediaCount"]),
                                        PlayedCount = SafeParser.ToNumber<int?>(rdr["PlayedCount"]),
                                        TrackCount = SafeParser.ToNumber<int?>(rdr["TrackCount"]),
                                        TotalTrackDuration = SafeParser.ToNumber<long?>(rdr["TotalTrackDuration"]),
                                        TotalTrackSize = SafeParser.ToNumber<long?>(rdr["TotalTrackSize"])
                                    };
                                }
                            }
                        }
                    }
                    catch (Exception ex)
                    {
                        this.Logger.LogError(ex);
                    }
                    finally
                    {
                        conn.Close();
                    }
                }
            }

            sw.Stop();
            return new OperationResult<LibraryStats>
            {
                IsSuccess = true,
                OperationTime = sw.ElapsedMilliseconds,
                Data = result
            };
        }
    }
}