//! Timing of `tm30::compute` on an HPCS 6500-like input (350 points,
//! 380-1050 nm). Run with `cargo run -p tm30 --release --example bench`.

use std::time::Instant;

fn main() {
    // Warm-white LED-like spectrum: blue pump + broad phosphor, on the HPCS
    // 6500 wavelength grid.
    let wl: Vec<f64> = (0..350).map(|i| 380.0 + 670.0 * i as f64 / 349.0).collect();
    let values: Vec<f64> = wl
        .iter()
        .map(|&w| {
            let blue = (-((w - 450.0) / 12.0).powi(2)).exp();
            let phosphor = 1.6 * (-((w - 600.0) / 70.0).powi(2)).exp();
            blue + phosphor
        })
        .collect();

    let t0 = Instant::now();
    let first = tm30::compute(&wl, &values).expect("valid spectrum");
    let cold = t0.elapsed();

    let n = 200;
    let t1 = Instant::now();
    let mut rf = 0.0;
    for _ in 0..n {
        rf += tm30::compute(&wl, &values).expect("valid spectrum").rf;
    }
    let warm = t1.elapsed() / n;
    assert!((rf / n as f64 - first.rf).abs() < 1e-12);

    println!(
        "Rf {:.2} Rg {:.2} CCT {:.0} K Duv {:.4}",
        first.rf, first.rg, first.cct_k, first.duv
    );
    println!("first call (parses tables, builds Planckian table): {cold:?}");
    println!("per call afterwards (mean of {n}): {warm:?}");
}