// Copyright (c) 2021 Weird Constructor <weirdconstructor@gmail.com>
// This file is a part of HexoDSP. Released under GPL-3.0-or-later.
// See README.md and COPYING for details.

use crate::nodes::{NodeAudioContext, NodeExecContext};
use crate::dsp::biquad::Oversampling;
use crate::dsp::helpers::{VPSOscillator, apply_distortion};
use crate::dsp::{
    NodeId, SAtom, ProcBuf, DspNode, LedPhaseVals, NodeContext,
    GraphAtomData, GraphFun,
};

#[macro_export]
macro_rules! fa_vosc_ovrsmpl { ($formatter: expr, $v: expr, $denorm_v: expr) => { {
    let s =
        match ($v.round() as usize) {
            0  => "Off",
            1  => "On",
            _  => "?",
        };
    write!($formatter, "{}", s)
} } }

const OVERSAMPLING : usize = 4;

/// A simple amplifier
#[derive(Debug, Clone)]
pub struct VOsc {
    israte: f32,
    osc:    VPSOscillator,
    oversampling: Box<Oversampling<OVERSAMPLING>>,
}

impl VOsc {
    pub fn new(nid: &NodeId) -> Self {
        let init_phase = nid.init_phase();

        Self {
            israte:       1.0 / 44100.0,
            osc:          VPSOscillator::new(init_phase),
            oversampling: Box::new(Oversampling::new()),
        }
    }

    pub const freq : &'static str =
        "VOsc freq\nBase frequency of the oscillator.\n\nRange: (-1..1)\n";
    pub const det : &'static str =
        "VOsc det\nDetune the oscillator in semitones and cents. \
         the input of this value is rounded to semitones on coarse input. \
         Fine input lets you detune in cents (rounded). \
         A signal sent to this port is not rounded.\n\
         Note: The signal input allows detune +-10 octaves.\
         \nRange: (Knob -0.2 .. 0.2) / (Signal -1.0 .. 1.0)\n";
    pub const d : &'static str =
        "VOsc d\nThis is the horzontal bending point of the waveform. \
        It has a similar effect that pulse width settings have on other \
        oscillators. Make sure to try modulating this parameter at audio rate!\
        \nRange: (0..1)\n";
    pub const v : &'static str =
        "VOsc v\nThis is the vertical bending point of the waveform. \
        You can adjust the effect that 'd' has on the waveform with this \
        parameter. Make sure to try to modulate this parameter at audio rate!\
        \nRange: (0..1)\n";
    pub const vs : &'static str =
        "VOsc vs\nScaling factor for 'v'. If you increase this beyond 1.0, \
        you will hear formant like sounds from the oscillator. Try adjusting \
        'd' to move the formants around.\nRange: (0..1)\n";
    pub const dist : &'static str =
        "VOsc dist\nA collection of waveshaper/distortions to choose from.";
    pub const damt : &'static str =
        "VOsc damt\nDistortion amount.\nRange: (0..1)\n";
    pub const ovrsmpl : &'static str =
        "VOsc ovrsmpl\nEnable/Disable oversampling.";
    pub const sig : &'static str =
        "VOsc sig\nOscillator output\nRange: (-1..1)\n";
    pub const DESC : &'static str =
r#"V Oscillator

A vector phase shaping oscillator, to create interesting waveforms and ways to manipulate them. It has two parameters ('v' and 'd') to shape the phase of the sinusoid wave, and a 'vs' parameter to add extra spice. Distortion can beef up the oscillator output and you can apply oversampling.
"#;
    pub const HELP : &'static str =
r#"VOsc - Vector Phase Shaping Oscillator
A vector phase shaping oscillator, to create interesting waveforms and
ways to manipulate them. It has two parameters ('v' and 'd') to shape the
phase of the sinusoid wave, and a third parameter 'vs' to add extra spice.
With distortion you can beef up the oscillator output even more and to
make it more harmonic you can apply oversampling.
"#;

}

impl DspNode for VOsc {
    fn outputs() -> usize { 1 }

    fn set_sample_rate(&mut self, srate: f32) {
        self.israte = 1.0 / (srate * (OVERSAMPLING as f32));
        self.oversampling.set_sample_rate(srate);
    }

    fn reset(&mut self) {
        self.oversampling.reset();
        self.osc.reset();
    }

    #[inline]
    fn process<T: NodeAudioContext>(
        &mut self, ctx: &mut T, _ectx: &mut NodeExecContext,
        _nctx: &NodeContext,
        atoms: &[SAtom], inputs: &[ProcBuf],
        outputs: &mut [ProcBuf], ctx_vals: LedPhaseVals)
    {
        use crate::dsp::{out, inp, denorm, denorm_offs, at};

        let freq    = inp::VOsc::freq(inputs);
        let det     = inp::VOsc::det(inputs);
        let d       = inp::VOsc::d(inputs);
        let v       = inp::VOsc::v(inputs);
        let vs      = inp::VOsc::vs(inputs);
        let damt    = inp::VOsc::damt(inputs);
        let out     = out::VOsc::sig(outputs);
        let ovrsmpl = at::VOsc::ovrsmpl(atoms);
        let dist    = at::VOsc::dist(atoms);

        let israte = self.israte;

        let dist       = dist.i() as u8;
        let oversample = ovrsmpl.i() == 1;

        let osc = &mut self.osc;

        if oversample {
            for frame in 0..ctx.nframes() {
                let freq = denorm_offs::VOsc::freq(freq, det.read(frame), frame);
                let v    = denorm::VOsc::v(v, frame).clamp(0.0, 1.0);
                let d    = denorm::VOsc::d(d, frame).clamp(0.0, 1.0);
                let vs   = denorm::VOsc::vs(vs, frame).clamp(0.0, 20.0);
                let damt = denorm::VOsc::damt(damt, frame).clamp(0.0, 1.0);

                let v = VPSOscillator::limit_v(d, v + vs);

                let overbuf = self.oversampling.resample_buffer();
                for b in overbuf {
                    let s = osc.next(freq, israte, d, v);
                    *b = apply_distortion(s, damt, dist);
                }

                out.write(frame, self.oversampling.downsample());
            }

        } else {
            for frame in 0..ctx.nframes() {
                let freq = denorm_offs::VOsc::freq(freq, det.read(frame), frame);
                let v    = denorm::VOsc::v(v, frame).clamp(0.0, 1.0);
                let d    = denorm::VOsc::d(d, frame).clamp(0.0, 1.0);
                let vs   = denorm::VOsc::vs(vs, frame).clamp(0.0, 20.0);
                let damt = denorm::VOsc::damt(damt, frame).clamp(0.0, 1.0);

                let v = VPSOscillator::limit_v(d, v + vs);
                let s = osc.next(freq, israte * (OVERSAMPLING as f32), d, v);
                let s = apply_distortion(s, damt, dist);

                out.write(frame, s);
            }
        }

        ctx_vals[0].set(out.read(ctx.nframes() - 1));
    }

    fn graph_fun() -> Option<GraphFun> {
        let mut osc = VPSOscillator::new(0.0);
        let israte = 1.0 / 128.0;

        Some(Box::new(move |gd: &dyn GraphAtomData, init: bool, _x: f32, _xn: f32| -> f32 {
            if init {
                osc.reset();
            }

            let v     = NodeId::VOsc(0).inp_param("v").unwrap().inp();
            let vs    = NodeId::VOsc(0).inp_param("vs").unwrap().inp();
            let d     = NodeId::VOsc(0).inp_param("d").unwrap().inp();
            let damt  = NodeId::VOsc(0).inp_param("damt").unwrap().inp();
            let dist  = NodeId::VOsc(0).inp_param("dist").unwrap().inp();

            let v     = gd.get_denorm(v as u32).clamp(0.0, 1.0);
            let d     = gd.get_denorm(d as u32).clamp(0.0, 1.0);
            let vs    = gd.get_denorm(vs as u32).clamp(0.0, 20.0);
            let damt  = gd.get_denorm(damt as u32);
            let dist  = gd.get(dist as u32).map(|a| a.i()).unwrap_or(0);

            let v = VPSOscillator::limit_v(d, v + vs);
            let s = osc.next(1.0, israte, d, v);
            let s = apply_distortion(s, damt, dist as u8);

            (s + 1.0) * 0.5
        }))
    }
}