#!/bin/bash

# Setup script directory
cd ~
mkdir scripts
cd ~/scripts

# Install check disk script
echo "Install check disk script"
touch check-disk.sh
chmod +x check-disk.sh
cat <<'EOF' > check-disk.sh
#!/bin/bash
 
IP_ADDRESS=$(ip addr show | awk '/inet / && /scope global/{split($2, a, "/"); print a[1]; exit}')
usage_threshold=80
main_partition=$(df -h | awk '$NF=="/"{print $(NF-1)}' | tr -d '%')

if [ -n "$main_partition" ] && [ "$main_partition" -gt "$usage_threshold" ]; then
 echo "Disk warning on: $IP_ADDRESS" | mail -s "`hostname` Disk usage over 80% ($main_partition)" support@starltd.net
else
 echo "Disk OK: $main_partition% / 100%"
fi
EOF
# Add to crontab
cat <<< '# Check if disk if full every 1 h
0 * * * * root /root/scripts/check-disk.sh' >> /etc/crontab

# Install check RAM script
echo "Install check RAM script"
touch check-ram.sh
chmod +x check-ram.sh
cat <<'EOF' > check-ram.sh
#!/bin/bash

IP_ADDRESS=$(ip addr show | awk '/inet / && /scope global/{split($2, a, "/"); print a[1]; exit}')
# Get CPU and RAM usage with top
ram_usage=$(top -b -n 1 | grep "MiB Mem" | awk '{print $8/$4 * 100}')

# Check if RAM usage is higher than 80%
if (( $(echo "$ram_usage > 80" | bc -l) )); then
  # Restart php/mysqld
  systemctl restart php*
  #systemctl restart mysqld
  # Send email
  echo "`hostname` $IP_ADDRESS RAM usage: $ram_usage%" | mail -s "`hostname` php/mysql restart High Memory usage" support@starltd.net
else
  echo "RAM Ok"
fi
EOF
# Add to crontab
cat <<< '# Check if RAM is over 80% / restart php-fpm+mysqld
* * * * * root /root/scripts/check-ram.sh' >> /etc/crontab

if systemctl status mysqld | grep "active" > /dev/null; then
echo "Install MYSQL script"
touch check-mysqld.sh
chmod +x check-mysqld.sh
cat <<'EOF' > check-mysqld.sh
#!/bin/bash

IP_ADDRESS=$(ip addr show | awk '/inet / && /scope global/{split($2, a, "/"); print a[1]; exit}')
if systemctl status mysqld.service | grep "active (running)" > /dev/null; then
   echo "MySQL OK"
else
   systemctl restart mysqld.service
   echo "MySQL restart on: $IP_ADDRESS" | mail -s "`hostname` MySQL restart" support@starltd.net
fi
EOF
# Add to crontab
cat <<< '# Check mysqld service / restart
* * * * * root /root/scripts/check-mysqld.sh' >> /etc/crontab
else
    echo "MYSQL does not exists, skipping.."
fi

if systemctl status httpd | grep "active" > /dev/null; then
    echo "Install HTTPD script"
touch check-httpd.sh
chmod +x check-httpd.sh
cat <<'EOF' > check-httpd.sh
#!/bin/bash

IP_ADDRESS=$(ip addr show | awk '/inet / && /scope global/{split($2, a, "/"); print a[1]; exit}')
if systemctl status httpd.service | grep "active (running)" > /dev/null; then
   echo "Apache OK"
else
   systemctl restart httpd.service
   echo "Apache restart on: $IP_ADDRESS" | mail -s "`hostname` Apache restart" support@starltd.net
fi
EOF
# Add to crontab
cat <<< '# Check httpd service / restart
* * * * * root /root/scripts/check-httpd.sh' >> /etc/crontab
else
    echo "HTTPD does not exists, skipping.."
fi

if systemctl status apache2 | grep "active" > /dev/null; then
    echo "Install Apache script"
touch check-apache2.sh
chmod +x check-apache2.sh
cat <<'EOF' > check-apache2.sh
#!/bin/bash

IP_ADDRESS=$(ip addr show | awk '/inet / && /scope global/{split($2, a, "/"); print a[1]; exit}')
if systemctl status apache2.service | grep "active (running)" > /dev/null; then
   echo "Apache OK"
else
   systemctl restart apache2.service
   echo "Apache restart on: $IP_ADDRESS" | mail -s "`hostname` Apache restart" support@starltd.net
fi
EOF
# Add to crontab
cat <<< '# Check apche2 service / restart
* * * * * root /root/scripts/check-apache2.sh' >> /etc/crontab
else
    echo "Apache does not exists, skipping.."
fi

if systemctl status nginx | grep "active" > /dev/null; then
    echo "Install NGINX script"
touch check-nginx.sh
chmod +x check-nginx.sh
cat <<'EOF' > check-nginx.sh
#!/bin/bash

IP_ADDRESS=$(ip addr show | awk '/inet / && /scope global/{split($2, a, "/"); print a[1]; exit}')
if systemctl status nginx.service | grep "active (running)" > /dev/null; then
   echo "Nginx OK"
else
   systemctl restart nginx.service
   echo "Nginx restart on: $IP_ADDRESS" | mail -s "`hostname` Nginx restart" support@starltd.net
fi
EOF
# Add to crontab
cat <<< '# Check nginx service / restart
* * * * * root /root/scripts/check-nginx.sh' >> /etc/crontab
else
    echo "NGINX does not exists, skipping.."
fi

if systemctl status redis-server | grep "active" > /dev/null; then
    echo "Install Redis script"
touch check-redis.sh
chmod +x check-redis.sh
cat <<'EOF' > check-redis.sh
#!/bin/bash

IP_ADDRESS=$(ip addr show | awk '/inet / && /scope global/{split($2, a, "/"); print a[1]; exit}')
if systemctl status redis-server.service | grep "active (running)" > /dev/null; then
   echo "Redis OK"
else
   systemctl restart redis-server.service
   echo "Redis restart on: $IP_ADDRESS" | mail -s "`hostname` Redis restart" support@starltd.net
fi
EOF
# Add to crontab
cat <<< '# Check redis service / restart
* * * * * root /root/scripts/check-redis.sh' >> /etc/crontab
else
    echo "Redis does not exists, skipping.."
fi

# Check if a parameter was provided
if [ $# -eq 0 ]; then
    echo "URL was not provided, skipping CURL check"
else
    echo "Installing curl script for: $1"
touch check-curl.sh
chmod +x check-curl.sh
#cat <<'EOF' > check-curl.sh
cat >> check-curl.sh <<EOF 
#!/bin/bash

IP_ADDRESS=\$(ip addr show | awk '/inet / && /scope global/{split(\$2, a, "/"); print a[1]; exit}')
if curl -skL -m 10 --head $1/?\$RANDOM | grep "HTTP/2 200" > /dev/null; then
   echo "FPM is UP"
else
   systemctl restart php*.service
   echo "\`hostname\` \$IP_ADDRESS php-fpm restart" | mail -s "\`hostname\` php-fpm restart" support@starltd.net
fi
EOF
# Add to crontab
cat <<< '# Check if 200/OK
* * * * * root /root/scripts/check-curl.sh' >> /etc/crontab
fi

echo "Done installing!"