# emits `TR_RACK_<GUN>=both` for the kept gun and `TR_RACK_<GUN>=off` for every
# other gun, so the rack can never silently fall back to the FULL-rack
# degradation when the target gun's `=both` was forgotten.
# usage: arm_env.sh <full|onlyLinear|onlyPattern|onlyTMPATTERN|onlyGF|onlyKNN|lean8|lean6|pairPC|pairPK|pairPL>
arm="$1"
GUNS="HEADON LINEAR TSETLIN CIRCULAR GUESSFACTOR PATTERN WALLBOUNCE ACCEL STOPSHOT DISPLACE AVGLEAD DECAYGF KNN TMSELECT TMPATTERN"
if [ "$arm" = "full" ]; then
  # Every gun `both` (the process default is onlyPattern, so this must be
  # explicit).
  keep="$GUNS"
else
case "$arm" in
  onlyLinear)    keep="LINEAR";;
  onlyPattern)   keep="PATTERN";;
  onlyTMPATTERN) keep="TMPATTERN";;
  onlyGF)        keep="GUESSFACTOR";;
  onlyKNN)       keep="KNN";;
  # ── small-good-rack follow-up ──────────────────────────────────────────────
  lean8)        keep="HEADON LINEAR CIRCULAR ACCEL PATTERN GUESSFACTOR KNN WALLBOUNCE";;
  lean6)        keep="LINEAR CIRCULAR ACCEL PATTERN GUESSFACTOR KNN";;
  pairPC)       keep="PATTERN CIRCULAR";;
  pairPK)       keep="PATTERN KNN";;
  pairPL)       keep="PATTERN LINEAR";;
  *) echo "unknown arm $arm" >&2; exit 1;;
esac
fi
out=""
for g in $GUNS; do
  case " $keep " in
    *" $g "*) out="$out TR_RACK_${g}=both";;
    *)        out="$out TR_RACK_${g}=off";;
  esac
done
echo "$out"