use crate::*;

pub fn buffer_update (buf: &mut Buffer, area: [u16;4], callback: &impl Fn(&mut Cell, u16, u16)) {
    for row in 0..area.h() {
        let y = area.y() + row;
        for col in 0..area.w() {
            let x = area.x() + col;
            if x < buf.area.width && y < buf.area.height {
                callback(buf.get_mut(x, y), col, row);
            }
        }
    }
}

#[derive(Default)]
pub struct BigBuffer {
    pub width:   usize,
    pub height:  usize,
    pub content: Vec<Cell>
}

impl BigBuffer {
    pub fn new (width: usize, height: usize) -> Self {
        Self { width, height, content: vec![Cell::default(); width*height] }
    }
    pub fn get (&self, x: usize, y: usize) -> Option<&Cell> {
        let i = self.index_of(x, y);
        self.content.get(i)
    }
    pub fn get_mut (&mut self, x: usize, y: usize) -> Option<&mut Cell> {
        let i = self.index_of(x, y);
        self.content.get_mut(i)
    }
    pub fn index_of (&self, x: usize, y: usize) -> usize {
        y * self.width + x
    }
}

from!(|size:(usize, usize)| BigBuffer = Self::new(size.0, size.1));