#!/bin/sh

. /etc/utils.sh

MONITOR_PATH="/tmp/ledmonitor"
MFG_MODE_FILE="$MONITOR_PATH/mfg_mode"
ACS_FILE="$MONITOR_PATH/acsconnected"
NETWORK_STATUS_FILE="$MONITOR_PATH/glaserstatus"
NETWORK_STATUS_CONNECTED="CONNECTED"
LED_STATE_FILE="/tmp/ledstate"
LED_PATH="/sys/class/leds/sys-"
BLUE_LED="blue"
RED_LED="red"
SOLID_MODE="solid"
BLINK_MODE="blink"
FAST_MODE="fast"
PON_IFACE="pon0"
MAN_IFACE="man"

led_state=""

set_led_brightness() {
  local color="$1"
  local brightness="$2"
  local path="$LED_PATH""$color"

  # when the trigger is disabled the led will assume the brightness value, so
  # set the brightness first to avoid glitching.
  echo "$brightness" > "$path/brightness"
  echo "none" > "$path/trigger"
}

blink_led() {
  local color="$1"
  local delay_on="$2"
  local delay_off="$3"
  local path="$LED_PATH""$color"
  local trigger="$(cat "$path/trigger")"

  # only set the trigger if it's not already set, otherwise the kernel will
  # first disable the blink, then re-enable it, possibly glitching the led.
  # 'none' is always the first listed trigger.
  if [ "${trigger#\[none\]}" != "$trigger" ] ; then
    echo "timer" > "$path/trigger"
  fi

  # the driver waits until both the on and off durations are non-zero before
  # enabling blinking.
  echo "$delay_on" > "$path/delay_on"
  echo "$delay_off" > "$path/delay_off"
}

set_led_state() {
  local mode="$1"
  local color="$2"
  local state="$mode $color"

  case "$color" in
    "$BLUE_LED")
      set_led_brightness "$RED_LED" "0"
      ;;
    "$RED_LED")
      set_led_brightness "$BLUE_LED" "0"
      ;;
    *)
      echo "unknown color '$color'"
      ;;
  esac

  case "$mode" in
    "$SOLID_MODE")
      set_led_brightness "$color" "1"
      ;;
    "$BLINK_MODE")
      blink_led "$color" "1000" "500"
      ;;
    "$FAST_MODE")
      blink_led "$color" "500" "500"
      ;;
    *)
      echo "unknown mode '$mode'"
      ;;
  esac

  if [ "$state" != "$led_state" ] ; then
    echo "state changed to '$state'"
    atomic $LED_STATE_FILE "$state"
    led_state="$state"
  fi
}

is_interface_up() {
  [ -n "$(ip link show $1 2>/dev/null | grep LOWER_UP)" ]
}

has_ip_address() {
  [ -n "$(ip -f inet6 addr show dev $1 scope global 2>/dev/null)" ] ||
    [ -n "$(ip -f inet addr show dev $1 scope global 2>/dev/null)" ]
}

watch-dir $MONITOR_PATH |
while [ -z "$led_state" ] || read event; do
  network_status=""
  if [ -e "$NETWORK_STATUS_FILE" ] ; then
    network_status="$(cat "$NETWORK_STATUS_FILE")"
  fi

  if [ -e "$MFG_MODE_FILE" ] ; then
    # Override the led to to blink super fast if we're in manufacture mode.
    # This should never happen for an installer, if it does then they'll know
    # something is wrong.
    blink_led "$RED_LED" "250" "250"
    blink_led "$BLUE_LED" "250" "250"
  elif ! is_interface_up "$PON_IFACE" ; then
    set_led_state "$BLINK_MODE" "$RED_LED"
  elif [ runnable glaser -a "$network_status" != "$NETWORK_STATUS_CONNECTED" ] ; then
    set_led_state "$FAST_MODE" "$RED_LED"
  elif ! has_ip_address "$MAN_IFACE" ; then
    set_led_state "$BLINK_MODE" "$BLUE_LED"
  elif [ ! -e $ACS_FILE ] ; then
    set_led_state "$FAST_MODE" "$BLUE_LED"
  else
    set_led_state "$SOLID_MODE" "$BLUE_LED"
  # TODO(showarth): upgrading
  fi
done