#!/bin/bash
#==== Includes=====================================
#cd /usr/src/mor
#. "$(pwd)"/sh_scripts/install_configs.sh
#. "$(pwd)"/sh_scripts/mor_install_functions.sh
#====end of Includes===============================

DEBUG="0";  #{ "1" - show calculated ram amount, "0" - NO debug info}

#-------- Percentage (%) values for various settings. All values must be from range 1.00 - 80.00 -----------

PERCENT_query_cache_size="3.13"                     # 3.13 %
PERCENT_join_buffer_size="0.39"
PERCENT_thread_cache_size="0.20"
PERCENT_innodb_buffer_pool_size="12.5"
PERCENT_table_cache="3.13"

PERCENT_key_buffer="0.78"
PERCENT_thread_stack="0.03"
PERCENT_query_cache_limit="0.39"

#-------- STATIC values for various settings in MB--------------

max_allowed_packet="100M"

if [ ! -f /usr/bin/bc ]; then
    yum -y install bc   #for math in bash
fi

#============================================== MAIN =========================================================================
insert_line_after_pattern()
{	#special characters need to be escaped like:   \$
	#arg1 - pattern
	#arg2 - what to add
	#arg3 - path to file
	#example: insert_line_after_pattern "\[mysqld\]" "max_allowed_packet=100M" "/etc/my.cnf"

	if [ ! -f "$3" ]; then return 1; fi

	cat "$3" | grep "$2" &> /dev/null

	if [ $? == 0 ]; then
		#report_to_stdout 0 "$2 already exist in $3";
		echo -e "[\E[33m  ALREADY EXIST \E[37m]\t$2";
	else
		cp $3 $3.mor_backup;
		sed '/'$1'.*$/a\'$2'' "$3" > /tmp/.mor_tmp && cat /tmp/.mor_tmp > "$3" && rm -rf /tmp/.mor_tmp
		#---------
		cat "$3" | grep "$2" &> /dev/null
		if [ $? == 0 ]; then
			echo -e "[\E[33m  ADDED \E[37m]\t$2";
		else
			echo -e "[\E[31m FAILED \E[37m]\t$2";
		fi
	fi
}
#-----------
calculate_ram_amount()
{
    #Arguments
        #1 - total RAM
        #2 - percent of RAM
    #Returns:
        #$AMOUNT_OF_RAM - the calculated amount of RAM (integer value)


    if [ ! -x "/usr/bin/bc" ]; then
        yum -y install bc
        if [ ! -x "/usr/bin/bc" ]; then
            echo "Failed to install bc, cannot continue";
            exit 1;
        fi

    fi

    #-----------------------------------------------------------
    AMOUNT_OF_RAM=`echo "scale=0; $1*$2/100" | bc 2>&1`
    if [ "$AMOUNT_OF_RAM" == "0" ]; then    #if calculation failed
        #echo "An error encountered during the calculation of RAM in function calculate_ram_amount with parameters: 1: $1, 2:$2"
        #echo "Further proceeding can lead to undesirable results, exiting while it is safe"
        AMOUNT_OF_RAM=1
        if [ "$DEBUG" == "1" ]; then echo "\$AMOUNT_OF_RAM="$AMOUNT_OF_RAM;        fi

    fi
}
#-----
backup_my_cnf()
{
    mor_time=`date +%Y\.%-m\.%-d\-%-k\-%-M\-%-S`;
    echo "Backing up your current /etc/my.cnf config to /usr/local/mor/backups/my_cnf/my.cnf_$mor_time"
    mkdir -p /usr/local/mor/backups/my_cnf
    cp /etc/my.cnf /usr/local/mor/backups/my_cnf/my.cnf_$mor_time
}
#-----
replace_setting_if_different_or_none()
{
    #arguments
        #1 - setting to check if exist
        #2 - setting to replace with if 1 and 2 are different

    CURRENT_SETTING=`grep $1 /etc/my.cnf`

    if [ "$CURRENT_SETTING" == "" ]; then
        echo "$CURRENT_SETTING"
        insert_line_after_pattern "\[mysqld\]" "$2" "/etc/my.cnf"
        RESTART_REQUIRED="yes"
    elif [ ! "$CURRENT_SETTING" == "$2" ]; then
        cat /etc/my.cnf | sed "s/.*$1.*/$2/g" >/tmp/my_cnf1 ; mv /tmp/my_cnf1 /etc/my.cnf
        echo -e "[\E[33mUpdated\E[37m]\t$2";
        RESTART_REQUIRED="yes"
    elif [ "$CURRENT_SETTING" == "$2" ]; then
        echo -e "[\E[32m   OK   \E[37m]\t$2";
    fi
}
#============================================================================================================================

if [ ! -r "/etc/redhat-release" ]; then
    echo "Sorry, but currently MOR supports only CentOS";
fi

#===== SYSTEM =====
#-- RAM
set $(free -m)
TOTAL_RAM="$8"  #Total RAM in MB

#-- Processors
processor_count=`egrep -c $'^processor[ \t]+:' /proc/cpuinfo`
processor_count=$((processor_count*2))

#================= Calculate correct RAM amounts for current system hardware======================

calculate_ram_amount $TOTAL_RAM $PERCENT_query_cache_size "query_cache_size"
    query_cache_size='query_cache_size='$AMOUNT_OF_RAM'M'

calculate_ram_amount $TOTAL_RAM $PERCENT_join_buffer_size "join_buffer_size"
    join_buffer_size='join_buffer_size='$AMOUNT_OF_RAM'M'

calculate_ram_amount $TOTAL_RAM $PERCENT_thread_cache_size "thread_cache_size"
    thread_cache_size='thread_cache_size='$AMOUNT_OF_RAM'M'

calculate_ram_amount $TOTAL_RAM $PERCENT_innodb_buffer_pool_size "innodb_buffer_pool_size"
    innodb_buffer_pool_size='innodb_buffer_pool_size='$AMOUNT_OF_RAM'M'

calculate_ram_amount $TOTAL_RAM $PERCENT_table_cache "table_cache"
    table_cache='table_cache='$AMOUNT_OF_RAM'M'

calculate_ram_amount $TOTAL_RAM $PERCENT_key_buffer "key_buffer"
    key_buffer='key_buffer='$AMOUNT_OF_RAM'M'

calculate_ram_amount $TOTAL_RAM $PERCENT_thread_stack "thread_stack"
    thread_stack='thread_stack='$AMOUNT_OF_RAM'M'

calculate_ram_amount $TOTAL_RAM $PERCENT_query_cache_limit "query_cache_limit"
    query_cache_limit='query_cache_limit='$AMOUNT_OF_RAM'M'

#======================================================================================
RESTART_REQUIRED="NO"  # resetting

backup_my_cnf

replace_setting_if_different_or_none "query_cache_size" "$query_cache_size"
replace_setting_if_different_or_none "join_buffer_size" "$join_buffer_size"
replace_setting_if_different_or_none "thread_cache_size" "$thread_cache_size"
replace_setting_if_different_or_none "innodb_buffer_pool_size" "$innodb_buffer_pool_size"
replace_setting_if_different_or_none "table_cache" "$table_cache"
replace_setting_if_different_or_none "max_allowed_packet" "max_allowed_packet=$max_allowed_packet"
replace_setting_if_different_or_none "thread_concurrency" "thread_concurrency=$processor_count"
replace_setting_if_different_or_none "skip-bdb" "skip-bdb"
replace_setting_if_different_or_none "key_buffer" "$key_buffer"
replace_setting_if_different_or_none "thread_stack" "$thread_stack"
replace_setting_if_different_or_none "query_cache_limit" "$query_cache_limit"

if [ "$RESTART_REQUIRED" = "yes" ]; then
    /etc/init.d/mysqld restart
fi