mod config;
mod corpus;
mod layout;

use core::cmp::Ordering;
use rayon::prelude::*;

use rand::prelude::*;
use rand_pcg::*;

use corpus::*;
use layout::*;

fn main() {
    let corpus = Corpus::load("chained_english_bigrams_1m.txt").unwrap();
    println!("{}", corpus);

    let starting_layout = Layout::from_verbose(
        "
        Y W F L M  K P O , Q
        U R S N H  D T E A I
        Z X C V J  B G ' . /
        ",
    )
    .unwrap();

    let mut rng = Pcg64::from_entropy();

    type Fun = Vec<(Layout, Evaluation, f32)>;

    let mut best = std::f32::INFINITY;
    let mut layouts: Fun = (0..10)
        .into_iter()
        .map(|i| {
            let layout;
            if i >= 0 {
                layout = Layout::new_random_from(&starting_layout, &mut rng);
            } else {
                layout = starting_layout;
            }

            let evl = corpus.evaluate_layout(&layout);
            let fitness = evl.fitness();
            return (layout, evl, fitness);
        })
        .collect();

    let mut counter: u64 = 0;
    while counter < 10000000000000 {
        let new_layouts = layouts
            .iter()
            .enumerate()
            .map(|(i, (kbd, _, _))| {
                if i > 0 {
                    Layout::new_random_from(kbd, &mut rng)
                } else {
                    kbd.clone()
                }
            })
            .collect::<Vec<Layout>>();

        new_layouts
            .par_iter()
            .map(|layout| {
                let evl = corpus.evaluate_layout(layout);
                let fitness = evl.fitness();
                return (*layout, evl, fitness);
            })
            .collect_into_vec(&mut layouts);

        layouts.sort_by(|(_, _, lfit), (_, _, rfit)| {
            if lfit < rfit {
                Ordering::Less
            } else {
                Ordering::Greater
            }
        });

        if layouts[0].2 < best {
            best = layouts[0].2;
            println!("");
            println!("================================================================================\nLayout:\n{}",
                         layouts[0].0
                    );

            println!("{}\n{}", layouts[0].1, layouts[0].2);
        }

        counter += 1;
    }
}