PlazaSharp/WinPlaza/MainWindow.xaml.cs

using System;
using System.Runtime.InteropServices;
using System.Threading.Tasks;
using System.Timers;
using System.Windows;
using System.Windows.Media.Imaging;
using libplaza;
using ManagedBass;

namespace WinPlaza {
	public partial class MainWindow : Window {
		static readonly object BufferLock=new object();
		private int BuffCh;
		private int BufferReqs;
		string LastArtwork="";
		Nightwave plaza=new Nightwave();
		Timer tRefresh;
		Timer tAudio;
		bool AudioInit=false;
		public MainWindow() {
			InitializeComponent();
			tRefresh = new Timer(300) { AutoReset = true };
			tRefresh.Elapsed += evtRefresh;
			tRefresh.Start();
			if(!Bass.Init())
				sbStatus.Text = "Unable to initialise audio subsystem";
			else
				AudioInit = true;
			if(!AudioInit)
				return;
			tAudio = new Timer(50);
			tAudio.Elapsed += evtAud;
			Bass.NetPlaylist = 1;
			Bass.NetPreBuffer = 0;
		}

		private void evtAud(object sender, ElapsedEventArgs e) =>
			_ = Dispatcher.BeginInvoke(new dgtNoParam(dgtAud));

		~MainWindow() {
			if(AudioInit)
				_ = Bass.Free();
		}
		private void _Status(string s) => sbStatus.Text = s;
		private void SetStatus(string msg) => Dispatcher.BeginInvoke(new dgtStr(_Status), msg);
		private void _Title(string s) => Title = s;
		private void SetTitle(string msg) => Dispatcher.BeginInvoke(new dgtStr(_Title), msg);
		private void LoadUri(string uri) => Task.Factory.StartNew(() => {
			int r;
			lock(BufferLock)
				r = ++BufferReqs;
			tAudio.Stop();
			_ = Bass.StreamFree(BuffCh);
			SetStatus("Connecting stream..");
			int stream = Bass.CreateStream(uri, 0, BassFlags.StreamDownloadBlocks | BassFlags.StreamStatus | BassFlags.AutoFree, StatusProc, new IntPtr(r));
			lock(BufferLock) {
				if(r != BufferReqs) {
					if(stream != 0)
						_ = Bass.StreamFree(stream);
				}
				BuffCh = stream;
			}
			if(BuffCh == 0)
				SetStatus("Unable to connect to stream");
			else
				tAudio.Start();
		});
		private void StatusProc(IntPtr buf, int len, IntPtr usr) {
			if(buf != IntPtr.Zero && len == 0 && usr.ToInt32() == BufferReqs)
				SetStatus(Marshal.PtrToStringAnsi(buf));
		}
		private void EndSync(int hdl, int ch, int dat, IntPtr usr) {
			SetStatus("Idle..");
			SetTitle("Nightwave.Net");
		}
		private void MetaSync(int hdl, int ch, int dat, IntPtr usr) => Dispatcher.BeginInvoke(new dgtBool(dgtRefresh), true);
		private void evtRefresh(object sender, ElapsedEventArgs e) =>
			_ = Dispatcher.BeginInvoke(new dgtBool(dgtRefresh), false);
		private delegate void dgtNoParam();
		private delegate void dgtBool(bool b);
		private delegate void dgtStr(string s);
		private async void dgtRefresh(bool Force = false) {
			Nightwave.Status s=await plaza.Broadcast(Force);
			slDuration.Value = s.CalculatedElapsed;
			sbListeners.Text = $"{s.Listeners} listeners";
			lbLikeCt.Content = s.Likes;
			lbDislikeCt.Content = s.Dislikes;
			lbElapsed.Content = $"{(s.CalculatedElapsed / 60).ToString("D")}:{(s.CalculatedElapsed % 60).ToString("D2")}";
			if(LastArtwork != s.ArtworkUri) {
				lbArtist.Content = s.Artist;
				lbTitle.Content = s.Title;
				lbAlbum.Content = s.Album;
				if(btPlayPause.IsChecked == true)
					SetTitle($"▶ {s.Title} - {s.Artist}");
				slDuration.Maximum = s.Duration;
				lbTime.Content = $"{(s.Duration / 60).ToString("D")}:{(s.Duration % 60).ToString("D2")}";
				art.Source = new BitmapImage(new Uri(s.ArtworkUri));
				LastArtwork = s.ArtworkUri;
			}
		}
		private void dgtAud() {
			long progress = Bass.StreamGetFilePosition(BuffCh, FileStreamPosition.Buffer)
								* 100 / Bass.StreamGetFilePosition(BuffCh, FileStreamPosition.End);
			if(progress > 75 || Bass.StreamGetFilePosition(BuffCh, FileStreamPosition.Connected) == 0) {
				tAudio.Stop();

				sbStatus.Text = "Playing";
				SetTitle($"▶ {lbTitle.Content} - {lbArtist.Content}");
				/*
								IntPtr icy = Bass.ChannelGetTags(BuffCh, TagType.ICY);
								if(icy == IntPtr.Zero)
									icy = Bass.ChannelGetTags(BuffCh, TagType.HTTP);
								if(icy != IntPtr.Zero) {
									foreach(string tag in Extensions.ExtractMultiStringAnsi(icy)) {
										string icymeta = string.Empty;
										if(tag.StartsWith("icy-name:"))
											icymeta += $"ICY Name: {tag.Substring(9)}";
										if(tag.StartsWith("icy-url:"))
											icymeta += $"ICY Url: {tag.Substring(8)}";
										//IcyMeta = icymeta;
									}
								}*/
				_ = Bass.ChannelSetSync(BuffCh, SyncFlags.MetadataReceived, 0, MetaSync);
				_ = Bass.ChannelSetSync(BuffCh, SyncFlags.OggChange, 0, MetaSync);
				_ = Bass.ChannelSetSync(BuffCh, SyncFlags.End, 0, EndSync);
				_ = Bass.ChannelPlay(BuffCh);
			} else
				sbStatus.Text = $"Buffering... {progress}%";
		}

		private void PlazaLoad() => LoadUri("https://radio.plaza.one/ogg");
		private void PlazaStop() {
			lock(BufferLock) {
				_ = Bass.StreamFree(BufferReqs);
				_ = Bass.StreamFree(BuffCh);
				_ = Bass.ChannelStop(BufferReqs);
				_ = Bass.ChannelStop(BuffCh);
				tAudio.Stop();
				SetStatus("Idle..");
				SetTitle("Nightwave.Net");
			}
		}

		private void BtPlayPause_Click(object sender, RoutedEventArgs e) {
			if(!AudioInit)
				return;
			if(btPlayPause.IsChecked == true)
				_ = Dispatcher.BeginInvoke(new dgtNoParam(PlazaLoad));
			else
				_ = Dispatcher.BeginInvoke(new dgtNoParam(PlazaStop));
		}
	}
}