"""Count WCAG 2.2 text contrast for all opaque 8-bit sRGB background codes."""
import json

def count_backgrounds():
    channels=[code/255 for code in range(256)]
    linear=[v/12.92 if v<=0.04045 else ((v+0.055)/1.055)**2.4 for v in channels]
    blues=[0.0722*v for v in linear]
    counts={'noir_seul':0,'blanc_seul':0,'les_deux':0,'aucun':0}
    for red in linear:
        for green in linear:
            rg=0.2126*red+0.7152*green
            for blue in blues:
                luminance=rg+blue
                black=(luminance+0.05)/0.05>=4.5
                white=1.05/(luminance+0.05)>=4.5
                label=('les_deux' if white else 'noir_seul') if black else ('blanc_seul' if white else 'aucun')
                counts[label]+=1
    return counts

if __name__=='__main__':
    print(json.dumps(count_backgrounds(),indent=2))