sendmail via curl

#!/bin/bash

function getinfo
{
        echo "" >> /tmp/mail.txt
        echo "Technical INFO:" >> /tmp/mail.txt
        echo "" >> /tmp/mail.txt
        hostname --ip >> /tmp/mail.txt
        free  >> /tmp/mail.txt
        df -h  >> /tmp/mail.txt
        echo "" >> /tmp/mail.txt
        echo "Asterisk STATUS: " >> /tmp/mail.txt
        service asterisk status  >> /tmp/mail.txt
        echo "" >> /tmp/mail.txt
        echo "Centos8 STATUS: " >> /tmp/mail.txt
        systemctl status cockpit.socket >>  /tmp/mail.txt
        echo "" >>  /tmp/mail.txt
        echo "Registration's STATUS:" >>  /tmp/mail.txt
        asterisk -rx "sip show peers" | grep -v Unspecified >>  /tmp/mail.txt
}

dt=`date`
host=($(hostname --ip | tr " " "\n"))

if [ -n "$1" ]
then
        echo "From: root@$host <automailer@asterisk.com>" > /tmp/mail.txt
        echo "To: Customer <$1>" >> /tmp/mail.txt
        echo "Subject: Новое событие на SIP сервере TrueIP $host" >> /tmp/mail.txt
        echo "Date: $dt" >> /tmp/mail.txt
else
        echo ""
        echo "Using: ./sendmail TO MESSAGE [file to attach] [TECHINFO]"
        echo "Powered by iMiro Wrench. Saint-Petersburg, Russia, July 2020"
        echo ""
        exit 0
fi

if [ -n "$2" ]
then
        echo "" >> /tmp/mail.txt
        echo $2 >> /tmp/mail.txt
else
        echo "" >> /tmp/mail.txt
        echo "Something happens now on your SIP server." >> /tmp/mail.txt
        getinfo
fi
if [ -n "$3" ]
then
        FILE=$1
        if [ -f "$FILE" ]; then
                echo "" >> /tmp/mail.txt
                echo "--------------------Attached file:--------------------" >> /tmp/mail.txt
                echo "" >> /tmp/mail.txt
                cat $3 >> /tmp/mail.txt
                echo "" >> /tmp/mail.txt
                echo "-----------------End of attached file:----------------" >> /tmp/mail.txt
        else
                getinfo
        fi
fi
        echo "" >> /tmp/mail.txt
        echo "Best regards, TrueIP Team. Saint-Petersburg, Russia. 2020" >> /tmp/mail.txt
if [ -n "$4" ]
then
        getinfo
fi
curl --ssl-reqd \
        --url 'smtps://smtp.gmail.com:465' \
        --user 'timianalias@gmail.com:aa483861' \
        --mail-from 'automailer@asterisk.com' \
        --mail-rcpt `echo $1` \
        --upload-file /tmp/mail.txt