use itertools::Itertools;
use rustysynth::SoundFont;
use rustysynth::Synthesizer;
use rustysynth::SynthesizerSettings;
use std::fs::File;
use std::sync::Arc;
use tinyaudio::prelude::*;

fn main() {
   // Load the SoundFont.
   let mut sf2 = File::open("FatBoy.sf2").unwrap();
   let sound_font = Arc::new(SoundFont::new(&mut sf2).unwrap());

   // Setup the audio output.
   let params = OutputDeviceParameters {
      channels_count: 2,
      sample_rate: 44100,
      channel_sample_count: 4410,
   };

   // Create the synthesizer.
   let settings = SynthesizerSettings::new(params.sample_rate as i32);
   let mut synthesizer = Synthesizer::new(&sound_font, &settings).unwrap();

   // Play some notes (middle C, E, G). // 16 channels actually // 60=c 64=e 67=g //up to 128velocity though dont go below 50 tbh
   synthesizer.note_on(0, 64, 100);
   //synthesizer.render(&mut left[..], &mut right[..]); // puts in a state of rendering the first loop of these notes

   // The recycled output buffer per-loop, could be in lamba but that'd be wasteful
   let sample_count = (params.channel_sample_count) as usize;
   let mut left: Vec<f32> = vec![0_f32; sample_count];
   let mut right: Vec<f32> = vec![0_f32; sample_count];
   // Start the audio output. Executes channel_sample_count per loop, sample_rate/channel_sample_count per second forever.
   let _device = run_output_device(params, {
      move |data| {
         synthesizer.render(&mut left[..], &mut right[..]); // put in a state of rendering the next loop of these notes
         for (i, value) in left.iter().interleave(right.iter()).enumerate() {
            data[i] = *value;
         }
      }
   })
   .unwrap();

   // Let it ride
   std::thread::sleep(std::time::Duration::from_secs(1));
}