#!/bin/bash
ARCHPATH='/path/to/backup/daily/*'
SKIPDBS=('mysql' 'tables' 'to' 'skip')
FULLRESTORE=true
SKIPDBS=('mysql')
SETPOSDB=db_for_master_log_position
CFG='~/.my.cnf'
#---

START=$(date +%s)

if [[ $(grep -q user ~/.my.cnf) ]] then
    echo -e "ERROR: 'user' field not found in '$CFG'"
    exit;
fi

if [[ $(grep -q password ~/.my.cnf) ]] then
    echo -e "ERROR: 'password' field not found in '$CFG'"
    exit;
fi

echo -e "\n--START: $(date +%F\ %T)\nrestoring most recent backups from $ARCHPATH\n\n"

echo -e "\nstopping replication\n";
mysql -e "STOP SLAVE;"


if [[ $FULLRESTORE == false ]]; then
    OLDDATE=$(ls -1d $ARCHPATH | head -1)
    echo "files will be compared to '$OLDDATE'"
else
    echo "full restorion"
fi

NEWDATE=$(ls -1rd $ARCHPATH | head -1)
for FILE in $NEWDATE/backup_data/*.gz; do
    FILE=$(basename $FILE)
    if [[ "${SKIPDBS[*]}" =~ ${FILE%%.*} ]]; then echo "-- skipping $FILE";continue; fi;        
    if [[ "${SETPOSDB}" =~ ${FILE%%.*} ]]; then echo "-- recognized $FILE for master position and log file";SETPOSFILE=$FILE; fi;
    if [[ -z $OLDDATE ]]; then 
        OLDSIZE=$(stat -c %s $OLDDATE/backup_data/$FILE)
    else
        OLDSIZE=0
    fi

    NEWSIZE=$(stat -c %s $NEWDATE/backup_data/$FILE)
    
    if [[ $OLDSIZE != $NEWSIZE ]]; then
    	STARTLOOP=$(date +%s)
    	echo -e "\n$(date +%F\ %T) | $FILE:"
        DB=$(echo $FILE | cut -f1 -d'.')
        echo -e "\tDROPPING/CREATING '$DB'
        pv $NEWDATE/backup_data/$FILE | gunzip | mysql $DB"
        mysql -e "DROP DATABASE IF EXISTS $DB"
        mysql -e "CREATE DATABASE $DB"
        pv $NEWDATE/backup_data/$FILE | gunzip | mysql $DB
        ENDLOOP=$(date +%s)
        EXCTIME=$(expr $ENDLOOP - $STARTLOOP)
		printf '\t%02dh:%02dm:%02ds\n' $((EXCTIME/3600)) $((EXCTIME%3600/60)) $((EXCTIME%60))        
    fi
done

if [[ -z $SETPOSFILE ]]; then
    SETPOSSTMT =$(zcat $ARCHPATH$SETPOSFILE|head -40|rg MASTER|sed 's/-- //')
    echo "\n$SETPOSSTMT\n"
    mysql -e $SETPOS
fi

mysql -e "START SLAVE"
END=$(date +%s)
EXCTIME=$(expr $END - $START)
printf 'total runtime: %02dh:%02dm:%02ds\n' $((EXCTIME/3600)) $((EXCTIME%3600/60)) $((EXCTIME%60)
echo "--END: $(date +%F\ %T)\n\n"