"""ERDTREE R02, raw PWM duty percentages; no photometric calibration claim."""
import math

PINS=(0,2,4,6)
DEFAULT=(22,48,82,12)
NIGHT=(5,12,22,3)
MODES=('常亮','缓慢呼吸','夜灯','关闭')

def duty_u16(percent):
    percent=float(percent)
    if not math.isfinite(percent):
        raise ValueError('finite duty required')
    return round(max(0,min(100,percent))*65535/100)

def levels(mode,elapsed_s):
    if mode==0:return DEFAULT
    if mode==1:
        a=math.sin(elapsed_s*2*math.pi/10)
        return (22,48+5*a,82+8*a,12)
    if mode==2:return NIGHT
    if mode==3:return (0,0,0,0)
    raise ValueError('unknown mode')

class DebouncedPress:
    def __init__(self,now_ms):
        self.last_raw=1;self.stable=1;self.changed_ms=now_ms
    def update(self,raw,now_ms,diff):
        if raw!=self.last_raw:
            self.last_raw=raw;self.changed_ms=now_ms
        if diff(now_ms,self.changed_ms)>=40 and raw!=self.stable:
            self.stable=raw
            return raw==0
        return False