PlazaSharp/libplaza/Main.cs

using System;
using System.Net.Http;
using Newtonsoft.Json;
using System.Threading.Tasks;

namespace libplaza {
	internal class PlazaApi {
		internal const string ApiBase="https://api.plaza.one/";
		internal const string ArtworkBase="https://plaza.one/";
		internal const string RadioBase="https://radio.plaza.one/";
	}
	public class PlazaPlayback {
		public string artist;
		public string title;
		public string album;
		public int length;
		public int position;
		public long updated;
		public string artwork;
		public string artwork_s;
		public int likes;
		public int hates;
	}
	public class PlazaJson {
		public bool maintenance;
		public int listeners;
		[JsonProperty]
		public PlazaPlayback playback;
	}
	internal class PlazaInMaintenanceException : Exception { }
	internal class PlazaUnavailableException : Exception { }
	public class Nightwave {
		public int MinRefreshTime=10;
		private long tsLastRefresh=0;
		private static HttpClient _hcl=new HttpClient();
		public enum BroadcastStatus {
			OffAir,
			OnAir
		}
		public struct Status {
			public string Title;
			public string Artist;
			public string Album;
			public string ArtworkUri;
			public int Elapsed;
			public int Duration;
			public long Since;
			public int CalculatedElapsed;
			public int Likes;
			public int Dislikes;
			public int Listeners;
		}
		private Status _bc;
		public BroadcastStatus Broadcasting=BroadcastStatus.OffAir;
		public Nightwave() {
			_hcl.BaseAddress = new Uri(PlazaApi.ApiBase);
			_hcl.DefaultRequestHeaders.Accept.Clear();
			_hcl.DefaultRequestHeaders.Accept.Add(
				new System.Net.Http.Headers.MediaTypeWithQualityHeaderValue("application/json"));
		}
		public async Task<Status> Broadcast() {
			_bc.CalculatedElapsed = (int)(DateTimeOffset.Now.ToUnixTimeSeconds() - _bc.Since) + _bc.Elapsed;
				if(tsLastRefresh+MinRefreshTime >= DateTimeOffset.Now.ToUnixTimeSeconds() && _bc.CalculatedElapsed < _bc.Duration)
					return _bc;
				try {
					Status _=await GetNightwaveAsync();
					Broadcasting = BroadcastStatus.OnAir;
					_bc = _;
				} catch(PlazaInMaintenanceException) {
					Broadcasting = BroadcastStatus.OffAir;
				} catch(PlazaUnavailableException) {
					Broadcasting = BroadcastStatus.OffAir;
				}
				tsLastRefresh = DateTimeOffset.Now.ToUnixTimeSeconds();
				return _bc;
		}

		public async void Update() {
			try {
				Status _=await GetNightwaveAsync();
				Broadcasting = BroadcastStatus.OnAir;
				_bc = _;
			} catch(PlazaInMaintenanceException) {
				Broadcasting = BroadcastStatus.OffAir;
			} catch(PlazaUnavailableException) {
				Broadcasting = BroadcastStatus.OffAir;
			}
		}
		public async Task<Status> GetNightwaveAsync() {
			Status status;
			HttpResponseMessage _r=await _hcl.GetAsync("/status");
			if(!_r.IsSuccessStatusCode)
				throw new PlazaUnavailableException();
			//string _=await _r.Content.ReadAsStringAsync();
			PlazaJson j=JsonConvert.DeserializeObject<PlazaJson>(await _r.Content.ReadAsStringAsync());
			if(j.maintenance)
				throw new PlazaInMaintenanceException();
			status = new Status {
				Title = j.playback.title,
				Album = j.playback.album,
				Artist = j.playback.artist,
				Elapsed = j.playback.position,
				Duration = j.playback.length,
				CalculatedElapsed = (int)(DateTimeOffset.Now.ToUnixTimeSeconds() - j.playback.updated) + j.playback.position,
				Since = j.playback.updated,
				Likes = j.playback.likes,
				Dislikes = j.playback.hates,
				Listeners = j.listeners,
				ArtworkUri = $"{PlazaApi.ArtworkBase}{j.playback.artwork}"
			};
			return status;
		}
	}
}