set_backlight

#!/bin/bash
set -xv
if [[ -f /tmp/auto_backlight.lock ]]; then
  exit 1
else
  touch /tmp/auto_backlight.lock
fi

log_file='/tmp/auto_backlight.log'
sensor_output_file='/sys/bus/acpi/devices/ACPI0008:00/iio:device0/in_illuminance_raw'

smoothly_adjust()
{
  while [[ "$cur_level" -lt "$target_level" ]]; do
    (( cur_level+=5 ))
    if [[ "$cur_level" -gt "$target_level" ]]; then
      light -S "$target_level"
    else
      light -A 5
    fi
    sleep 0.1
  done

  while [[ "$cur_level" -gt "$target_level" ]]; do
    (( cur_level-=5 ))
    if [[ "$cur_level" -lt "$target_level" ]]; then
      light -S "$target_level"
    else
      light -U 5
    fi
    sleep 0.1
  done
}

auto_set()
{
  now=$(date +%s)
  cur_level=$(( $(light | tr -d .) / 100 ))
  last_time=0

  if [[ -f $log_file ]]; then
    last_time=$(cat $log_file | awk '{ print $1 }')
#    last_level=$(cat $log_file | awk '{ print $2 }')
  fi

  interval=$((now - last_time))
  # 如果十分钟内设置了手动条调节
  [[ $interval -gt 600 ]] || return 1

  # 采样
  i=0
  average=0
  while [[ $i -lt 5 ]]; do
    (( average+=$(cat $sensor_output_file) ))
    sleep 0.1
    (( i = i + 1 ))
  done
  env_light=$((average / 5))
  if [[ $env_light -gt 100 ]]; then
    env_light=100
  fi
  target_level=$((env_light / 2 + 10))
  
  smoothly_adjust
}

while sleep 0.5; do
  auto_set
done