vim-terminal.applescript

tell application "Terminal"
	activate
	set allWindows to number of windows
	global found
	set found to false
	
	repeat with i from 1 to allWindows
		set allTabs to number of tabs of window i
		repeat with j from 1 to allTabs
			if processes of tab j of window i contains "nvim" then
				set frontmost of window i to true
				set selected of tab j of window i to true
				set found to true
			end if
		end repeat
	end repeat
	
	if not found then
		tell application "Terminal" to do script "vim"
	end if
end tell

Open VIM in MacOS Terminal. If already open selects corresponding tab. If not starts it.

Replace "nvim" with your vi flavor.