use super::*;
use regs::RegMosaic;

impl RegMosaic {
    fn is_enabled_for_bg(&self) -> bool {
        (self.bg_hsize() != 0) || (self.bg_vsize() != 0)
    }
}

impl Gpu {
    fn mosaic_bg(&mut self) {
        let hsize = (self.mosaic.bg_hsize() + 1) as usize;
        let vsize = (self.mosaic.bg_vsize() + 1) as usize;

        for bg in 0..4 {
            if self.dispcnt.disp_bg(bg) && self.bg[bg].bgcnt.mosaic() {
                let y = self.current_scanline as usize;
                if y % vsize == 0 {
                    self.bg[bg].mosaic_first_row = self.bg[bg].line.clone();
                }
                for x in 0..DISPLAY_WIDTH {
                    let color = self.bg[bg].mosaic_first_row[(x / hsize) * hsize];
                    self.bg[bg].line[x] = color;
                }
            }
        }
    }

    pub fn mosaic_sfx(&mut self) {
        if self.mosaic.is_enabled_for_bg() {
            self.mosaic_bg();
        }
        // TODO obj mosaic
    }
}