#!/usr/bin/env bash
# UKRRS day/night resource profile (REPORT.md section 5.5).
# Runtime-only changes (set-property --runtime + sysctl): a reboot always
# lands safely in day mode (slice unit files carry the day defaults).
set -euo pipefail
mode=${1:?usage: ukrrs-daynight.sh day|night}
CONF=/etc/ukrrs/daynight.conf
[ -r "$CONF" ] && . "$CONF"

: "${DATA2_DEV:=/dev/sdb}"
: "${BATCH_WEIGHT_DAY:=25}";        : "${BATCH_WEIGHT_NIGHT:=400}"
: "${BATCH_CPUS_DAY:=0-5}";         : "${BATCH_CPUS_NIGHT:=0-6}"
: "${BATCH_HIGH_DAY:=12G}";         : "${BATCH_HIGH_NIGHT:=30G}"
: "${GW_WEIGHT_DAY:=900}";          : "${GW_WEIGHT_NIGHT:=500}"
: "${DATA2_RA_DAY:=256}";           : "${DATA2_RA_NIGHT:=2048}"
: "${DIRTY_DAY:=1073741824}";       : "${DIRTY_NIGHT:=2147483648}"
: "${DIRTY_BG_DAY:=268435456}";     : "${DIRTY_BG_NIGHT:=536870912}"

log() { echo "[ukrrs-daynight] $*"; }
setprop() { systemctl set-property --runtime "$@"; }
setra() { blockdev --setra "$1" "$2" 2>/dev/null || log "readahead skip: $2"; }

case "$mode" in
night)
  setprop ukrrs-batch.slice \
    CPUWeight="$BATCH_WEIGHT_NIGHT" \
    AllowedCPUs="$BATCH_CPUS_NIGHT" \
    MemoryHigh="$BATCH_HIGH_NIGHT"
  setprop ukrrs-gateway.slice CPUWeight="$GW_WEIGHT_NIGHT"
  setra "$DATA2_RA_NIGHT" "$DATA2_DEV"; setra "$DATA2_RA_NIGHT" "${DATA2_DEV}1"
  sysctl -q -w vm.dirty_bytes="$DIRTY_NIGHT" vm.dirty_background_bytes="$DIRTY_BG_NIGHT"
  ;;
day)
  setprop ukrrs-batch.slice \
    CPUWeight="$BATCH_WEIGHT_DAY" \
    AllowedCPUs="$BATCH_CPUS_DAY" \
    MemoryHigh="$BATCH_HIGH_DAY"
  setprop ukrrs-gateway.slice CPUWeight="$GW_WEIGHT_DAY"
  setra "$DATA2_RA_DAY" "$DATA2_DEV"; setra "$DATA2_RA_DAY" "${DATA2_DEV}1"
  sysctl -q -w vm.dirty_bytes="$DIRTY_DAY" vm.dirty_background_bytes="$DIRTY_BG_DAY"
  ;;
*)
  echo "unknown mode: $mode" >&2; exit 2 ;;
esac
log "profile $mode applied $(date -Is)"