menus is ok

mailserver.sh

@@ -1,2 +1,46 @@
 #!/usr/bin/env bash
 
+usage(){
+    echo "usage: ./mailserver.sh [help] [install]"
+    echo "help: show this help"
+    echo "install: install exim/courier mail server"
+}
+
+RED='\033[91m'
+STD='\033[0m'
+
+[[ $# -lt 1 ]] && usage
+[[ $1 == "help" ]] && usage
+[[ $EUID -ne 0 ]] && echo -e "${RED}This script must be run as root${STD}" && exit 1
+
+install_exim() {
+    echo "lol"
+}
+
+install_spamassassin() {
+    echo "lol"
+}
+
+install_clamav() {
+    echo "lol"
+}
+
+install_mailserver() {
+    echo "Do you want to install extra software ?"
+    echo "1. None"
+    echo "2. SpamAssassin (antispam)"
+    echo "3. ClamAV (antivirus)"
+    echo "4. Both SpamAssassin and ClamAV"
+    echo "5. Exit"
+    read -p "Enter choice [1 - 4] " choice
+    case $choice in
+        1) clear && install_exim ;;
+        2) clear && install_exim && install_spamassassin ;;
+        3) clear && install_exim && install_clamav ;;
+        4) clear && install_exim && install_spamassassin && install_clamav ;;
+        5) exit ;;
+        *) clear && echo -e "${RED}Please enter a valid input${STD}" && install_mailserver ;;
+    esac
+}
+
+clear && [[ $1 == "install" ]] && install_mailserver