use super::*;
use ::livi::{
    World,
    Instance,
    Plugin as LiviPlugin,
    Features,
    FeaturesBuilder,
    Port,
    event::LV2AtomSequence,
};
use std::thread::JoinHandle;

/// A LV2 plugin.
pub struct LV2Plugin {
    pub world:        World,
    pub instance:     Instance,
    pub plugin:       LiviPlugin,
    pub features:     Arc<Features>,
    pub port_list:    Vec<Port>,
    pub input_buffer: Vec<LV2AtomSequence>,
    pub ui_thread:    Option<JoinHandle<()>>,
}

impl LV2Plugin {
    const INPUT_BUFFER: usize = 1024;
    pub fn new (uri: &str) -> Usually<Self> {
        // Get 1st plugin at URI
        let world    = World::with_load_bundle(&uri);
        let features = FeaturesBuilder { min_block_length: 1, max_block_length: 65536 };
        let features = world.build_features(features);
        let mut plugin = None;
        if let Some(p) = world.iter_plugins().next() { plugin = Some(p); }
        let plugin   = plugin.expect("plugin not found");
        let err      = &format!("init {uri}");
        let instance = unsafe { plugin.instantiate(features.clone(), 48000.0).expect(&err) };
        let mut port_list = vec![];
        for port in plugin.ports() {
            port_list.push(port);
        }
        let input_buffer = Vec::with_capacity(Self::INPUT_BUFFER);
        // Instantiate
        Ok(Self {
            world, instance, port_list, plugin, features, input_buffer, ui_thread: None
        })
    }
}