Using my ambient light sensor to work like true tone

• buffer0
• buffer
• current_timestamp_clock
• dev
• in_chromaticity_hysteresis
• in_chromaticity_hysteresis_relative
• in_chromaticity_offset
• in_chromaticity_sampling_frequency
• in_chromaticity_scale
• in_chromaticity_x_raw
• in_chromaticity_y_raw
• in_colortemp_hysteresis
• in_colortemp_hysteresis_relative
• in_colortemp_offset
• in_colortemp_raw
• in_colortemp_sampling_frequency
• in_colortemp_scale
• in_illuminance_hysteresis
• in_illuminance_offset
• in_illuminance_hysteresis_relative
• in_illuminance_raw
• in_illuminance_sampling_frequency
• in_illuminance_scale
• in_intensity_both_raw
• in_intensity_hysteresis
• in_intensity_hysteresis_relative
• in_intensity_offset
• in_intensity_sampling_frequency
• in_intensity_scale
• name
• power
• scan_elements
• subsystem
• trigger
• uevent

#!/usr/bin/env python3

import os
import time
import subprocess
import sys

# Sensor path
SENSOR_DIR = "/sys/bus/iio/devices/iio:device0"
RAW_FILE = os.path.join(SENSOR_DIR, "in_colortemp_raw")
SCALE_FILE = os.path.join(SENSOR_DIR, "in_colortemp_scale")

# GNOME Night Light settings
NIGHT_LIGHT_SCHEMA = "org.gnome.settings-daemon.plugins.color"
ENABLED_KEY = "night-light-enabled"
TEMPERATURE_KEY = "night-light-temperature"
SCHEDULE_KEY = "night-light-schedule-automatic"

# Mapping parameters (adjust based on your sensor's typical range)
MIN_AMBIENT_K = 2000.0  # Warmest ambient light (e.g., incandescent)
MAX_AMBIENT_K = 6500.0  # Coolest ambient light (e.g., daylight)
MIN_SCREEN_VAL = 6500  # Cool screen (matches cool ambient)
MAX_SCREEN_VAL = 4000  # Warm screen (matches warm ambient)


def read_sensor_value(file_path):
    """Read raw value from sysfs file."""
    try:
        with open(file_path, "r") as f:
            return float(f.read().strip())
    except (IOError, ValueError) as e:
        print(f"Error reading {file_path}: {e}", file=sys.stderr)
        return None


def get_color_temp():
    """Get color temperature in Kelvin from sensor."""
    raw = read_sensor_value(RAW_FILE)
    if raw is None:
        return None

    scale = 1.0  # Default if no scale file
    # commented out due to scale factor being reported wrong
    # scale_val = read_sensor_value(SCALE_FILE)
    # if scale_val is not None:
    #     # Parse scale (e.g., "0.0625" or "1 0.001" for integer + fractional)
    #     if " " in str(scale_val):
    #         int_part, frac_part = str(scale_val).split()
    #         scale = float(int_part) + float(frac_part)
    #     else:
    #         scale = float(scale_val)

    return raw * scale


def map_to_screen_temp(ambient_k):
    if ambient_k is None:
        return None
    # Clamp to expected range
    ambient_k = max(MIN_AMBIENT_K, min(MAX_AMBIENT_K, ambient_k))
    # Linear map: high K (cool ambient) -> low screen val (cool screen)
    # low K (warm ambient) -> high screen val (warm screen)
    normalized = (MAX_AMBIENT_K - ambient_k) / (MAX_AMBIENT_K - MIN_AMBIENT_K)
    return MIN_SCREEN_VAL + normalized * (MAX_SCREEN_VAL - MIN_SCREEN_VAL)


def update_night_light(temp_val):
    """Update GNOME Night Light via gsettings."""
    try:
        # Enable Night Light
        subprocess.run(
            ["gsettings", "set", NIGHT_LIGHT_SCHEMA, ENABLED_KEY, "true"], check=True
        )
        # Disable automatic scheduling to keep it always on
        subprocess.run(
            ["gsettings", "set", NIGHT_LIGHT_SCHEMA, SCHEDULE_KEY, "false"], check=True
        )
        # Set temperature (0.0 to 1.0)
        subprocess.run(
            [
                "gsettings",
                "set",
                NIGHT_LIGHT_SCHEMA,
                TEMPERATURE_KEY,
                str(int(temp_val)),
            ],
            check=True,
        )
        print(
            f"Updated screen temperature to {temp_val:.2f} (ambient ~{get_color_temp()}K)"
        )
    except subprocess.CalledProcessError as e:
        print(f"Error updating gsettings: {e}", file=sys.stderr)


def main():
    print("Starting True Tone-like adaptation...")
    print(f"Monitoring sensor at {RAW_FILE}")
    if os.path.exists(SCALE_FILE):
        print(f"Scale file found at {SCALE_FILE}")

    while True:
        ambient_k = get_color_temp()
        if ambient_k is not None:
            # just do 1:1 mapping here
            # screen_val = map_to_screen_temp(ambient_k)
            screen_val = ambient_k
            if screen_val is not None:
                update_night_light(screen_val)
        else:
            print("Skipping update: could not read sensor", file=sys.stderr)

        time.sleep(1)  # Check every 5 seconds (adjust as needed)


if __name__ == "__main__":
    # Check if sensor files exist
    if not os.path.exists(RAW_FILE):
        print(f"Sensor file not found: {RAW_FILE}", file=sys.stderr)
        print("Verify the device path with 'ls /sys/bus/iio/devices/'", file=sys.stderr)
        sys.exit(1)

    main()