#!/bin/bash

source=${1}
destination=${2}
user=${3:-root}
pass=${4}

# Help menu
print_help() {
        echo  -e "
\e[01;34mInstructions:\e[0m
This script is used to replicate database.
Following arguments are available in the script :

 1) \e[01;32m --source \e[0m  - Source database. (mandatory)
 2) \e[01;32m --destination \e[0m  - Destination database.(mandatory)
 3) \e[01;32m --user \e[0m  - Database user who have access to both source and destination database.(mandatory)
 4) \e[01;32m --pass \e[0m  - Password for the database user.(mandatory)


\e[01;36mUsage:\e[0m ./${0##*/} --source=DB --destination=DB --user=USERNAME --pass=PASSWORD


"
        exit 0
}


while [ $# -gt 0 ]; do
        case "$1" in
         --source=*)
                        source="${1#*=}"
                        ;;
                --destination=*)
                        destination="${1#*=}"
                        ;;
                --user=*)
                        user="${1#*=}"
                        ;;
                --pass=*)
                        pass="${1#*=}"
                        ;;
                --help) print_help
                        ;;
                *)
                        printf "Invalid argument passed to the script.\n";
                        exit 1
        esac
        shift
done

echo "Database replication started"

mysql -u$user -p$pass -e "DROP SCHEMA IF EXISTS $destination;"
mysql -u$user -p$pass -e "CREATE DATABASE IF NOT EXISTS $destination DEFAULT CHARACTER SET 'utf8' COLLATE 'utf8_unicode_ci';"
mysqldump -u$user -p$pass $source | mysql -u$user -p$pass $destination

echo "$source database has been replicated on $destination database."