use crate::BRIGHTNESS;
use crate::HEIGHT;
use crate::Q;
use crate::WIDTH;

pub struct Cell {
    pub x: u32,
    pub y: u32,
    pub state: u32,
}

pub fn init_grid(option: Option<&Vec<Vec<Cell>>>) -> Vec<Vec<Cell>> {
    let mut grid: Vec<Vec<Cell>> = Vec::new();
    for j in 0..HEIGHT {
        let mut row: Vec<Cell> = Vec::new();
        for i in 0..WIDTH {
            let mut value = rand::random::<u32>() % Q;
            if let Some(g) = option {
                value = g[j as usize][i as usize].state;
            }

            row.push(Cell {
                x: i,
                y: j,
                state: value,
            });
        }
        grid.push(row);
    }
    grid
}

fn map_num(n: usize, s: usize, e: usize, a: usize, b: usize) -> usize {
    (a as f64 + (n as f64 - s as f64) * (b as f64 - a as f64) / (e as f64 - s as f64)) as usize
}

pub fn display_grid(grid: &Vec<Vec<Cell>>) {
    for i in 0..HEIGHT {
        for j in 0..WIDTH {
            let x = i as usize;
            let y = j as usize;
            let state = grid[x][y].state as usize;

            let index = map_num(state, 0, Q as usize, 0, BRIGHTNESS.len());
            print!("{}", BRIGHTNESS.chars().nth(index).unwrap());
        }
        println!();
    }
}