#!/usr/bin/env bash

working_dir="$(dirname $(realpath $0))"
conf_file="${working_dir}/conf/mysql_credetials.conf"

#LOGGING=true
LOGGING=false

mysql=`realpath $(which mysql) 2>/dev/null`
if [ -z "$mysql" ]; then
   if [ -x "/usr/local/mysql/bin/mysql" ]; then
      mysql=/usr/local/mysql/bin/mysql
   else
      echo
      echo -e "\t[ Error ]: \"mysql\"  not found !!!"
      echo
      exit
   fi
fi

# Get current version
#
_MYSQLD_VERSION="$(mysqld -V 2>/dev/null)"
CURRENT_VERSION="$(echo $_MYSQLD_VERSION | grep -o -E "[0-9]+\.[0-9]+\.[0-9]+(-[0-9]+)?" | head -n 1)"

MYSQL_MAIN_VERSION=`echo $CURRENT_VERSION | cut -d '.' -f1,2`
MYSQL_MAJOR_VERSION=`echo $CURRENT_VERSION | cut -d '.' -f1`
MYSQL_MINOR_VERSION=`echo $CURRENT_VERSION | cut -d '.' -f2`
MYSQL_PATCH_LEVEL=`echo $CURRENT_VERSION | cut -d '.' -f3`

if [[ -z "$_MYSQLD_VERSION" ]]; then
   echo ""
   echo -e "\t[ Error ]: No installed MySQL server or distribution found!"
   echo ""
elif [[ "$_MYSQLD_VERSION" =~ MariaDB ]]; then
	MYSQL_CUR_DISTRIBUTION="MariaDB"
elif [[ "$(basename "$(realpath "/usr/local/mysql")")" =~ percona- ]]; then
	MYSQL_CUR_DISTRIBUTION="Percona"
elif [[ "$(basename "$(realpath "/usr/local/mysql")")" =~ mysql- ]]; then
	MYSQL_CUR_DISTRIBUTION="MySQL"
fi

if [[ "$MYSQL_CUR_DISTRIBUTION" = "MySQL" ]]; then
	if [[ "$MYSQL_MAJOR_VERSION" -gt 8 ]] \
		||  ( [[ "$MYSQL_MAJOR_VERSION" -eq 8 ]] && [[ "$MYSQL_MINOR_VERSION" -gt 0 ]] ) \
		||  ( [[ "$MYSQL_MAJOR_VERSION" -eq 8 ]] && [[ "$MYSQL_MINOR_VERSION" -eq 0 ]] \
				&& [[ $MYSQL_PATCH_LEVEL -ge 3 ]] ); then
		echo ""
		echo -e "\t[ Error ]: Query cache is no longer supported since (MySQL 8.0.3)"
		echo ""
		exit
	fi
fi



#---------------------------------------
#-----------------------------
# Read Configurations from $conf_file
#-----------------------------
#---------------------------------------

if [[ -f "$conf_file" ]]; then
   source "$conf_file"
fi

#[[ -z "$mysql_credential_args" ]] && mysql_credential_args="--defaults-file=/usr/local/mysql/sys-maint.cnf"

if [[ -z "$mysql_credential_args" ]]; then

   if [[ "$MYSQL_CUR_DISTRIBUTION" = "MariaDB" ]] && ([[ $MYSQL_MAJOR_VERSION -gt 10 ]] \
         || ( [[ $MYSQL_MAJOR_VERSION -eq 10 ]] && [[ $MYSQL_MINOR_VERSION -gt 3 ]] )) ; then
      if [[ -S "/tmp/mysql.sock" ]]; then
         mysql_credential_args="-u root -S /tmp/mysql.sock"
      elif [[ -S "/var/run/mysqld/mysqld.sock" ]]; then
         mysql_credential_args="-u root -S /var/run/mysqld/mysqld.sock"
      else
         fatal "Parameter 'MYSQL_CREDENTIAL_ARGS' cannot be determined automated.

              Use configuration file "$conf_file" to set
              parameter manually."
      fi
   else
      if [[ -f "/usr/local/mysql/sys-maint.cnf" ]] ; then
         mysql_credential_args="--defaults-file=/usr/local/mysql/sys-maint.cnf"
      elif [[ -f "/etc/mysql/debian.cnf" ]] ; then
         mysql_credential_args="--defaults-file=/etc/mysql/debian.cnf"
      else
         fatal "Parameter 'MYSQL_CREDENTIAL_ARGS' cannot be determined automated.

              Use configuration file "$conf_file" to set
              parameter manually."
      fi
   fi

fi



if $LOGGING ;then
   echo -e "\n[ `date` ] Going to flush query cache.."
fi


# Flush Query Cache
#
$mysql $mysql_credential_args -N -s -e "FLUSH QUERY CACHE"

[[ $? -gt 0 ]] && echo -e "\t[ Error ]: Flushing query cache failed !!"

if $LOGGING ;then
    echo -e "\n[ `date` ] End flushing query cache"
fi

exit 0