batcal.am

let ac = "/sys/class/power_supply/AC"
let min_voltage = 9.6
let max_voltage = 12.6

fun err(stuff)   { unsafe $gum log -l error "{stuff}"$ }
fun fatal(stuff) { unsafe $gum log -l fatal "{stuff}"$ }
fun info(stuff)  { unsafe $gum log -l info  "{stuff}"$ }
fun warn(stuff)  { unsafe $gum log -l warn  "{stuff}"$ }

fun get_voltage(battery) {
  return unsafe $cat {battery}/voltage_now$ as Num / 1000000
}

fun get_status(battery) {
  return unsafe $cat {battery}/status$
}

fun actual_stats(battery) {
  let state = unsafe $cat {battery}/status$
  let energy_now = unsafe $cat {battery}/energy_now$ as Num / 1000000
  let energy_full = unsafe $cat {battery}/energy_full$ as Num / 1000000
  let energy_full_design = unsafe $cat {battery}/energy_full_design$ as Num / 1000000
  let voltage_now = get_voltage(battery)
  let capacity = unsafe $cat {battery}/capacity$
  let charge_behaviour = unsafe $cat {battery}/charge_behaviour$

  echo "\tStatus: {state}      "
  echo "\tCapacity: {capacity}      "
  echo "\tCharge behaviour: {charge_behaviour}      "
  echo "\tEnergy stored: {energy_now} Wh      "
  echo "\tEnergy full/design: {energy_full}/{energy_full_design} Wh      "
  echo "\tVoltage now: {voltage_now} V      "

}

fun print_stats(battery) {
  let bat_name = unsafe $echo {battery} | rev | cut -d '/' -f 1 | rev$
  info("Current stats of {bat_name} (as seen by the bms):")
  actual_stats(battery)
}

fun redraw_stats(battery) {
  unsafe $tput cuu 6$ // 6 lines up (gum is slow asf, so we're not redrawing it)
  actual_stats(battery)
}

fun detect_ac(){
  silent $ls "{ac}"$ failed {
    warn("Can't find the laptop's power supply directory. Please, specify manually.")
    ac = unsafe $gum choose /sys/class/power_supply/*$ //*/
  }

  let online = $cat {ac}/online$ failed {
    err("{ac}/online is not present or inaccessible")
  }

  if online == "0" {
    // TODO: implement the --no-charge flag
    err("Power supply not connected. Connect it and try again")
    fail 1
  }
}

fun set_charge_behaviour(charge_behaviour, battery) {
  info("Setting charge_behaviour to {charge_behaviour}")
  $echo "{charge_behaviour}" > {battery}/charge_behaviour$ ?
}

fun charge_cycle(battery) {
  // TODO: mb loop charge-discharge stuff 'til the battery reaches exactly max_voltage
  info("Started charge cycle.")
  unsafe set_charge_behaviour("auto", battery)
  print_stats(battery)
  loop {
    if get_voltage(battery) >= max_voltage or get_status(battery) == "Not charging" or get_status(battery) == "Full" {
      info("Battery voltage reached {max_voltage}, stopping charge cycle.")
      unsafe set_charge_behaviour("inhibit-charge", battery)
      break
    }
    unsafe $sleep 5$
    redraw_stats(battery)
  }

}

fun discharge_cycle(battery) {
  info("Started charge cycle.")
  unsafe set_charge_behaviour("force-discharge", battery)
  // TODO: custom discharge command
  let pid = unsafe $stress-ng --cpu 8 --cpu-method matrixprod --metrics-brief --perf &>/dev/null & echo \$! $
  print_stats(battery)
  loop {
    if get_voltage(battery) <= min_voltage {
      info("Battery voltage reached {min_voltage}, stopping discharge cycle.")
      unsafe $kill {pid}$
      break
    }
    unsafe $sleep 5$
    redraw_stats(battery)
  }
}

main {
  $gum log -l info "Availeable batteries:"$ failed {
    echo "Seems like gum is not installed. Make sure it is and try again."
    fail 1
  }

  let battery = unsafe $gum choose --select-if-one /sys/class/power_supply/BAT*$
  print_stats(battery)

  let battery_cells = unsafe $gum choose 2 3 4 --header "How many sequential cells does the battery have:"$ as Num
  min_voltage = 3.2 * battery_cells + 0.1
  max_voltage = 4.2 * battery_cells + 0.1
  info("Discharging down to {min_voltage }")
  info("Charging up to {max_voltage}")
  fail 1

  set_charge_behaviour("auto", battery) failed {
    fatal("Can't write to {battery}/charge_behaviour. I suggest re-running the script with root privilleges (sudo).")
    fail 1
  }

  let has_sysd = true
  silent $which systemctl$ failed {
    unsafe $gum confirm --affirmative="Ok" --negative="" "Seem to be running on a non-systemd distro. Stop upower if you're using it and press ok"$
    has_sysd = false
  }

  if has_sysd {
    let has_upower = true
    silent $systemctl list-unit-files | grep upower$ failed {
      has_upower = false
    }
    if has_upower {
      info("Detected upower. Stopping it.")
      unsafe $systemctl stop upower$
    }
  }

  detect_ac()?

  unsafe $gum confirm --affirmative="Ok" --negative="" "About to start cycling the battery. The process is infinite, you can Ctrl-c at any moment."$

  $gum confirm "Go straight to discharge cycle?"$ failed {
    charge_cycle(battery)
  }

  loop {
    discharge_cycle(battery)
    charge_cycle(battery)
  }

}