from machine import ADC, Pin
import time
from neopixel import NeoPixel

# ------------------- 硬件引脚配置 -------------------
# 光敏传感器：ESP32-S3 的 14 号引脚
adc_pin = Pin(14)
adc = ADC(adc_pin)
adc.atten(ADC.ATTN_11DB)   # 0~3.3V 量程
adc.width(ADC.WIDTH_12BIT) # 12位精度，0~4095

# WS2812 环形灯配置（按你的实际硬件修改）
led_pin = Pin(16, Pin.OUT)  # 数据引脚
num_leds = 16              # 灯珠数量
np = NeoPixel(led_pin, num_leds)

# ------------------- 亮度范围配置 -------------------
# 强光（ADC低）→ 弱亮度；弱光（ADC高）→ 强亮度
MIN_BRIGHTNESS = 10   # 最暗时的亮度（防止完全熄灭）
MAX_BRIGHTNESS = 255  # 最亮时的亮度

# ------------------- 主循环：线性平滑调光 -------------------
while True:
    # 读取光敏传感器ADC值（0~4095）
    adc_value = adc.read()
    
    # 线性映射：ADC值 → 亮度值（反向映射，光线越暗灯越亮）
    # 公式：亮度 = MIN_BRIGHTNESS + (MAX_BRIGHTNESS - MIN_BRIGHTNESS) * (adc_value / 4095)
    brightness = int(MIN_BRIGHTNESS + (MAX_BRIGHTNESS - MIN_BRIGHTNESS) * (adc_value / 4095))
    
    # 边界保护（防止超出 0~255 范围）
    brightness = max(MIN_BRIGHTNESS, min(MAX_BRIGHTNESS, brightness))
    
    # 设置所有灯珠为当前亮度的白色
    for i in range(num_leds):
        np[i] = (brightness, brightness, brightness)
    np.write()
    
    # 串口调试信息
    print(f"ADC值: {adc_value}, 亮度: {brightness}")
    
    # 适当延时，避免占用过高
    time.sleep(0.05)