use plotters::prelude::*;
use std::path::Path;
use wavegen::{sawtooth, sine, square, wf, Waveform};

fn main() -> Result<(), Box<dyn std::error::Error>> {
    let sample_rate = 800.0f32;

    draw(
        sample_rate,
        "sine.png",
        "Sine",
        Waveform::with_components(sample_rate, vec![sine!(1.)]),
    )?;

    draw(
        sample_rate,
        "sine_double.png",
        "Sines",
        wf!(f32, sample_rate, sine!(1.0), sine!(1.0, 1.0, 0.25)),
    )?;

    draw(
        sample_rate,
        "sawtooth.png",
        "Sawtooth",
        wf!(f32, sample_rate, sawtooth!(2., 1., 0.0)),
    )?;

    draw(
        sample_rate,
        "sawtooth_sinesised.png",
        "Sawtooth with sine",
        wf!(
            f32,
            sample_rate,
            sawtooth!(2., 1., 0.0),
            sine!(frequency: 50., amplitude: 0.1)
        ),
    )?;

    draw(
        sample_rate,
        "square.png",
        "Square",
        wf!(f32, sample_rate, square!(2.)),
    )?;

    draw(
        sample_rate,
        "funky.png",
        "Something funky",
        wf!(
            f32,
            sample_rate,
            sine!(10., 0.3),
            sawtooth!(2., 0.3),
            square!(3., 0.3)
        ),
    )?;

    draw(
        sample_rate,
        "sines_300_50_hz.png",
        "Sine 300Hz + 50 Hz",
        wf!(
            f32,
            sample_rate,
            sine!(frequency: 300.),
            sine!(frequency: 50., amplitude: 0.3)
        ),
    )?;

    Ok(())
}

fn draw(
    sample_rate: f32,
    path: impl AsRef<Path>,
    label: impl AsRef<str>,
    waveform: Waveform<f32>,
) -> Result<(), Box<dyn std::error::Error>> {
    draw_internal(
        path,
        label.as_ref(),
        waveform
            .iter()
            .enumerate()
            .map(|(i, x)| (i as f32 / sample_rate, x))
            .take(sample_rate as usize),
    )
}

fn draw_internal<I: IntoIterator<Item = (f32, f32)>, P: AsRef<Path>>(
    path: P,
    label: &str,
    iter: I,
) -> Result<(), Box<dyn std::error::Error>> {
    let img_path = Path::new("img").join(path);
    let root = BitMapBackend::new(&img_path, (800, 600)).into_drawing_area();
    root.fill(&WHITE)?;
    let mut chart = ChartBuilder::on(&root)
        // .caption(label, ("sans-serif", 50).into_font())
        .margin(5)
        .x_label_area_size(30)
        .y_label_area_size(30)
        .build_cartesian_2d(-0f32..1f32, -2f32..2f32)?;

    chart.configure_mesh().draw()?;

    chart
        .draw_series(LineSeries::new(iter, RED))?
        .label(label)
        .legend(|(x, y)| PathElement::new(vec![(x, y), (x + 20, y)], RED));

    chart
        .configure_series_labels()
        .background_style(WHITE.mix(0.8))
        .border_style(BLACK)
        .draw()?;

    Ok(())
}