/// Plays [Voice]s from [Sample]s.
/// 
/// ```
/// let sampler = tek::Sampler::default();
/// ```
#[derive(Debug, Default)] pub struct Sampler {
    /// Name of sampler.
    pub name: Arc<str>,
    /// Device color.
    pub color: ItemTheme,
    /// Sample currently being recorded.
    pub recording: Option<(usize, Option<Arc<RwLock<Sample>>>)>,
    /// Recording buffer.
    pub buffer: Vec<Vec<f32>>,
    /// Samples mapped to MIDI notes.
    pub samples: SampleKit<128>,
    /// Collection of currently playing instances of samples.
    pub voices: Arc<RwLock<Vec<Voice>>>,
    /// Samples that are not mapped to MIDI notes.
    pub unmapped: Vec<Arc<RwLock<Sample>>>,
    /// Sample currently being edited.
    pub editing: Option<Arc<RwLock<Sample>>>,
    /// How to mix the voices.
    pub mixing_mode: MixingMode,
    /// How to meter the inputs and outputs.
    pub metering_mode: MeteringMode,
    /// Fixed gain applied to all output.
    pub output_gain: f32,
    /// Currently active modal, if any.
    pub mode: Option<SamplerMode>,
    /// Size of rendered sampler.
    pub size: Measure<Tui>,
    /// Lowest note displayed.
    pub note_lo: AtomicUsize,
    /// Currently selected note.
    pub note_pt: AtomicUsize,
    /// Selected note as row/col.
    pub cursor: (AtomicUsize, AtomicUsize),
    /// Audio input meters.
    #[cfg(feature = "meter")] pub input_meters: Vec<f32>,
    /// Audio input ports. Samples are recorded from here.
    #[cfg(feature = "port")] pub audio_ins: Vec<AudioInput>,
    /// MIDI input port. Sampler are triggered from here.
    #[cfg(feature = "port")] pub midi_in: Option<MidiInput>,
    /// Audio output ports. Voices are played into here.
    #[cfg(feature = "port")] pub audio_outs: Vec<AudioOutput>,
    /// Audio output meters.
    #[cfg(feature = "meter")] pub output_meters: Vec<f32>,
}

/// Collection of samples, one per slot, fixed number of slots.
///
/// History: Separated to cleanly implement [Default].
///
/// ```
/// let samples = tek::SampleKit([None, None, None, None]);
/// ```
#[derive(Debug)] pub struct SampleKit<const N: usize>(
    pub [Option<Arc<RwLock<Sample>>>;N]
);

/// A sound cut.
///
/// ```
/// let sample = tek::Sample::default();
/// let sample = tek::Sample::new("test", 0, 0, vec![]);
/// ```
#[derive(Default, Debug)] pub struct Sample {
    pub name:     Arc<str>,
    pub start:    usize,
    pub end:      usize,
    pub channels: Vec<Vec<f32>>,
    pub rate:     Option<usize>,
    pub gain:     f32,
    pub color:    ItemTheme,
}

/// A currently playing instance of a sample.
#[derive(Default, Debug, Clone)] pub struct Voice {
    pub sample:   Arc<RwLock<Sample>>,
    pub after:    usize,
    pub position: usize,
    pub velocity: f32,
}

#[derive(Default, Debug)] pub struct SampleAdd {
    pub exited:  bool,
    pub dir:     PathBuf,
    pub subdirs: Vec<OsString>,
    pub files:   Vec<OsString>,
    pub cursor:  usize,
    pub offset:  usize,
    pub sample:  Arc<RwLock<Sample>>,
    pub voices:  Arc<RwLock<Vec<Voice>>>,
    pub _search: Option<String>,
}

#[derive(Debug)] pub enum SamplerMode {
    // Load sample from path
    Import(usize, Browse),
}

pub type MidiSample =
    (Option<u7>, Arc<RwLock<crate::Sample>>);