#!/usr/bin/env bash

## - *** some defines *** - ##

## - Backup direction
## -
backup_base_dir=$1
backup_base_dir=${backup_base_dir:="/data/backup"}

backup_dir=${backup_base_dir}/mysql

mkdir -p $backup_dir


_local=$2
_local=${_local:=false}

mkdir -p $backup_dir

## - Database connection data
## -
db_user=backup
db_pass=Rgfwcsgth6Zjk4W
db_host=localhost
db_port=3306

## - Some needed binaries
## -
mysql_bin=`which mysql`
mysqldump_bin=`which mysqldump`
mkdir_bin=`which mkdir`
date_bin=`which date`
gzip_bin=`which gzip`
find_bin=`which find`

if [ -z "$mysql" ]; then
   mysql="/usr/local/mysql/bin/mysql"
fi 

if [ -z "$mysqldump" ]; then
   mysqldump="/usr/local/mysql/bin/mysqldump"
fi



YEAR=`date +"%Y"`
MONTH=`date +"%m"`
DAY=`date +"%d"`
HOUR=`date +"%H"`
MINUTE=`date +"%M"`
DATE=${YEAR}${MONTH}${DAY}-${HOUR}${MINUTE}

## - Hold backups at least $days days
## -
days=3


## - ** End: some defines *** - ##



DATABASES=`$mysql_bin -h$db_host -P$db_port -u$db_user -p$db_pass -N -s -e 'show databases'`

## - backup all databases
## -
for i in $DATABASES ; do

   $mkdir_bin -p ${backup_dir}/${i}

   mysqldump_flags="--opt --routines -l"
   if [ "$i" = "information_schema" -o "$i" = "performance_schema" ];then
      mysqldump_flags="--single-transaction $mysqldump_flags"
   fi

   echo  -e "\tsave database $i ..."
   $mysqldump_bin  $mysqldump_flags  -h$db_host -P$db_port -u$db_user -p$db_pass $i |  \
      $gzip_bin | cat > ${backup_dir}/${i}/${i}-${DATE}.sql.gz

   ## - dumptables "user" and "db" from database mysql"
   ## -
   if [ "$i" = "mysql" ]; then
      _flags="--add-locks --disable-keys --extended-insert --lock-tables --quick --no-create-info"

      _table=user
      ## - dump table user (database mysql)
      ## -    each row as aseperate sql statement 
      ## -
      ## -       | awk '{gsub(/\),\(/,");\n(")}; 1'
      ## -       | sed 's/^(/INSERT INTO `user` VALUES (/'
      ## -
      ## -    delete row containig host = "localhost" with empty user and password
      ## -       sed "/^INSERT INTO \`user\` VALUES ('[^']*','root',.\+/d"
      ## -
      ## -    delete rows containig user "root"
      ## -       sed "/^INSERT INTO \`user\` VALUES ('[^']*','root',.\+/d"
      ## -
      ## -    delete rows containig user "debian-sys-maint"
      ## -       sed "/^INSERT INTO \`user\` VALUES ('[^']*','debian-sys-maint',.\+/d"
      ## -
      $mysqldump_bin $_flags -h$db_host -P$db_port -u$db_user -p$db_pass $i $_table \
         | awk '{gsub(/\),\(/,");\n(")}; 1' \
         | sed "s/^(/INSERT INTO \`$_table\` VALUES (/" \
         | sed "/^INSERT INTO \`$_table\` VALUES ('localhost','','','.*/d" \
         | sed "/^INSERT INTO \`$_table\` VALUES ('[^']*','root','.*/d" \
         | sed "/^INSERT INTO \`$_table\` VALUES ('[^']*','debian-sys-maint','.*/d" \
         > ${backup_dir}/${i}/${i}-${_table}-${DATE}.sql

      _table=db
      ## - dump table db (database mysql)
      ## -    each row as aseperate sql statement 
      ## -
      ## -       | awk '{gsub(/\),\(/,");\n(")}; 1'
      ## -       | sed 's/^(/INSERT INTO `user` VALUES (/'
      ## -
      ## -    delete rows for database names "test*"
      ## -       sed "/^INSERT INTO \`$_table\` VALUES ('[^']*','test[^']*','.*/d"
      ## -
      $mysqldump_bin $_flags -h$db_host -P$db_port -u$db_user -p$db_pass $i $_table \
         | awk '{gsub(/\),\(/,");\n(")}; 1' \
         | sed "s/^(/INSERT INTO \`$_table\` VALUES (/" \
         | sed "/^INSERT INTO \`$_table\` VALUES ('[^']*','test[^']*','.*/d" \
         > ${backup_dir}/${i}/${i}-${_table}-${DATE}.sql

      ## - BSD sed is not GNU sed , so we used "awk" for substitution
      ## - a newline. On GNU sed (like on linux systems), also the
      ## - following sed statement works 
      ## -
      #| sed 's/),(/);\n(/g' \
   fi

done

## - Create archive from the whole backup
## -
if ! $_local ; then
   _curdir=`pwd`
   cd $backup_dir
   cd .. > /dev/null 2>&1
   tar -czf mysql_dump-${DATE}.tar.gz `find mysql -name "*${DATE}*"`
   cd $_curdir
fi


## - remove all files older than $days days..
## - 
$find_bin $backup_dir -type f -mtime +${days} -exec rm {} \;

exit 0