#!/bin/bash
#============================================================================
#This is a script used to automatically backup a certain directory
#============================================================================
#author:yuanweiwei(yuanweiwei@gmail.com)
#date:2005.4.10
#version:1.0
#============================================================================
#This function func_f is used to back a certain file,its first parameter must
#be a file name which is a absolute path name,and the second is the dest
#directory where the file will be backed
func_f()
{

#if wrong parameters ,exit
if [ $# != 3 ]
then
echo "only $# parameters,bad parameters ,exit! in func_f"

exit 1
fi

filename=
dest_directory=
log=

#if the first parameter,which should be a filename is not exist or is a
#directory,exit
if [ ! -e $filename -o -d $filename ]
then
echo "$filename is not a file,exit!"
exit 1
fi

#if dest directory doesn't exit
    if [ ! -e $dest_directory ]
        then
        echo "dest directory $dest_directory doesn't exist,creat?"
        read com
#note that at this point root privilege maybe needed and should be checked,
#and command value should be checked
        if [ "$com" == "Y" -o "$com" == "y" -o "$com == "YES" -o "$com == "yes" ]
        then
        echo "begin to make dir $dest_directory"
        mkdir -p  $dest_directory
        elif [ "$com" == "N" -o "$com" == "n" -o "$com == "NO" -o "$com == "no" ]
        then
        exit 0
        else
        echo "unknown command,exit"
    fi
#if dest directory is not a directory ,exit
    elif [ ! -d $dest_directory ]
        then
        echo "$dest_directory is not a directory,exit"
        exit 0
    fi

#now everything is fixed,begin -:)
#get current time as suffix of the name of backup files
    backtime=$(date +%Y_%m_%d_%H_%M)
    echo $backtime
    suffixname=$backtime
    dest=$dest_directory/$_$suffixname
#if dest file exits,exit
    if [ -e $dest ]
    then
    echo "$dest exists,please wait one more minute"
    exit 0
    else
        cp $filename $dest
       if [ -e $log ]
       then
        echo "back $filename to $dest and exit status is $value" > $log
       else
        echo "back $filename to $dest and exit status is $value" >> $log
       fi    
   fi
}


#===========================================================================
#===========================================================================
#This function is used to backup a directory
#method:make a copy of a certain directory

func_d()
{
#if bad parameters ,exit
if [ $# != 1 -a $# != 2 -a $# != 3 ]
then
echo "bad parameters"
echo "usage:./execute sourcefile [dest_directory [log name]]"
exit 1
fi
default_dest=/usr/local/back/default
default_log=/usr/local/back/default/auto_back.log
source_directory=
#get the proper values for source directory dest directory and log file respetively
case $# in
1)
    dest_directory=$default_dest
    log_file=$default_log;;
2)
    dest_directory=
    log_file=$log;;
3)
    dest_directory=
    log_file=;;
esac

#if the source directory doestn't exist,exit
if [ ! -e $source_directory ]
then
echo "$source_directory doesn't exist,exit"
exit 1
elif [ ! -d $source_directory ]
then
echo "$source_directory is not a directory,exit"
exit 1
fi

#if the dest source directory doesn't exit,wait for another minute
if [ ! -e $dest_directory ]
then
echo "$dest_directory doesn't exist,create now?"
read comm
case $comm in
"y"|"Y"|"yes"|"YES")
mkdir -p $dest_directory;;
"n"|"N"|"NO"|"no")
exit 0;;
*)
echo "unknown command,exit"
exit 0;;
esac

#else,the dest_directory exist,but not a directory
elif [ ! -d $dest_directory ]
then
echo "$dest_directory is not a directory,pleace check it"
exit 0
fi

#now,the dest directory exists and is ok
backtime=$(date +%Y_%m_%d_%H_%M)
suffixname=$backtime
destination=$/$_$suffixname
#to see whether the destnation name exists
if [ -e $destination ]
then
echo "this directory has just been backed,please wait one more minute to back"
exit 0
fi

#now everything is ok,begin-:)
pathnow=$(pwd)
cp -a $source_directory $destination
#if [ ! -e $log_file]
#then
#echo "back directory $/$source_directory  to $destation" > $log_file
#else
exec 6>&1
exec >> $log_file
echo "back directory $/$source_directory  to $destination"
exec 1>&6 6>&-

#fi
#everything is fixed now
}

#=====================================================================
#start
#=====================================================================
default_directory="/usr/local/back/default"
logfile=$default_directory/auto_back.log
#see how many arguments
#======================================================================
if [ $# != 1 -a $# != 2 ]
then
echo "wrong parameters!"
echo "usage:./auto_back source_dirctory dest_directory"
exit 0
fi
#======================================================================
if [ ! -e ]
then
echo " doesn't,please check it"
exit 1;
fi

case $# in
1)
    if [ -f ]
    then
    func_f $default_directory $logfile
    else
    func_d $default_directory $logfile
    fi;;
2)                                                                                
      if [ -f ]
        then
        func_f $logfile
        else
        func_d $logfile
        fi;;
esac
#everything fixed ,exit
exit 0