import time
from collections import deque
import Adafruit_ADS1x15

adc = Adafruit_ADS1x15.ADS1115()
GAIN = 1
LSB = 4.096 / 32768.0

# show a slow breathing-friendly trace:
# - "v" is instantaneous diff voltage
# - "ac" is high-passed (removes slow drift) so breathing wiggles pop
alpha = 0.995  # closer to 1 = slower drift removal
dc = 0.0

buf = deque(maxlen=120)  # ~8-10s at your ~14Hz
t0 = time.time()

print("Breathing monitor D01 (A0-A1). Ctrl+C to stop.")
print("Tip: sit still 5s, then breathe deep/slow.")

while True:
    raw = adc.read_adc_difference(0, gain=GAIN)  # A0-A1
    v = raw * LSB

    # simple DC tracker + high-pass
    dc = alpha*dc + (1-alpha)*v
    ac = v - dc

    buf.append(ac)

    # auto-scale bar
    peak = max(1e-6, max(abs(x) for x in buf))
    width = 60
    pos = int((ac/peak)* (width//2)) + width//2
    pos = max(0, min(width-1, pos))

    line = [" "] * width
    line[width//2] = "|"
    line[pos] = "*"

    if time.time() - t0 > 0.10:
        print(f"v={v:+0.3f}V  ac={ac:+0.3f}V  peak={peak:0.3f}V  " + "".join(line), end="\r")
        t0 = time.time()

    time.sleep(0.01)