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ix!();

use crate::{
    NLSFType,
};

/**
** This contains an adaptation of the filter found at
** https://ccrma.stanford.edu/~jatin/ComplexNonlinearities/NLBiquad.html
** with coefficient calculation from
** https://webaudio.github.io/Audio-EQ-Cookbook/audio-eq-cookbook.html
**
** a lot of code here is duplicated from NonlinearFeedback.cpp, perhaps in future they
** could be merged, but for the time being they're separate and nothing is shared.
*/
#[derive(Derivative)] #[derivative(Debug)]
pub struct NonlinearStatesFilter {
    pub tuner:  TunerHandle,
    pub srunit: SampleRateHandle,
    pub ty:     NLSFType,
}

impl NonlinearStatesFilter {
    pub fn clamped_frequency(&self, pitch: f32) -> f32
    {
        let freq = self.tuner.n2p::<f32,true>(pitch + 69.0) * (MIDI_0_FREQ as f32);
        limit_range(freq, 5.0, self.srunit.samplerate_os() * 0.3)
    }
}