Make muliple panes in iTerm

make_panes.sh

#!/bin/zsh

repeatBy() { for i in {1..$(expr $1)}; do echo -n "$2"; done }

if [ "$#" -lt 2 ]; then
    echo "usage: $0 v h [command]"
    exit 1
fi

CMD="$3"

VER_CNT=$(expr $1 - 1)
VER_SPLIT=$(repeatBy $VER_CNT '            delay 0.3\n            keystroke "d" using command down\n')
VER_PREV=$(repeatBy $VER_CNT '            delay 0.1\n            keystroke "[" using command down\n')

HOR_CNT=$(expr $2)
HOR_ELEM="            delay 0.3\\\\\\\\n            keystroke textToType\\\\\\\\n            key code 36\\\\\\\\n"
HOR_ELEMS=$(repeatBy $HOR_CNT "\"$HOR_ELEM\"---")
HOR_SET=$(echo $HOR_ELEMS | sed "s/\"---\"/            keystroke \"D\" using command down\n/g" | sed "s/\\\\n/\\n/g")
HOR_ALL="${HOR_SET: 1:-5}"

ALL_CNT=$(expr $1)
VER_ELEMS=$(repeatBy $ALL_CNT "\"$HOR_ALL\"---")
VER_SET=$(echo $VER_ELEMS | sed "s/\"---\"/\n\n            delay 0.3\n            keystroke \"]\" using command down\n\n/g" | sed "s/\\\\n/\\n/g")
VER_ALL="${VER_SET: 1:-4}"

/usr/bin/env osascript <<-EOF
tell application "iTerm"
    activate
    launch session "Panes"

    tell application "System Events"
        tell process "iTerm"
            set textToType to "$CMD"

            keystroke "t" using command down

$VER_SPLIT

$VER_PREV

$VER_ALL
        end tell
    end tell

end tell
EOF

Usage

./make_panes.sh 2 4  # or
./make_panes.sh 3 3  # or
./make_panes.sh 4 3 "echo 1"
# ...