#!/bin/bash
#
# This backup script will backup selected files and folders in this manner:
# 1. Check if the backup-folder is valid for backing up to.
# 2. If there is already an existing backup, back that up into $tempdir/backup_{MDY}.tar.bz2.
# 3. Move all old .tar.bz2 backups from the backup-folder to $tempdir.
# 4. Delete the content of the old backup-folder.
# 5. Move back all .tar.bz2 (old and new backups) from $tempdir to the backup-folder.
# 6. Create directory structure from $mkdr.
# 7. Copy files ($File) and directories ($Dirs) to the backup-folder.
# 8. Check if any errors occurd and notify if so.


UNDERSTOOD="no"           # Change to yes to make this program functional (no not delete)!


path="/mnt/hdd6/backups"; # The path to where you want to store the backups (No ending slash!).
                          # This script will delete its content, so be warned!
tempdir="/tmp"            # Temporary folder to use (must be without ending slash, existing and writeable!).
errorlog=".errorlog";     # The filename of the errorlog (will be created if nonexistant).


# Edit the directories to be created in this order:
mkdr="
boot
etc
etc/X11
etc/conf.d
usr
usr/X11R6
usr/X11R6/bin
var
var/spool
var/spool/cron
var/spool/cron/crontabs";

# Edit your files and folders here (do not use any wildcards!):
ver=$(uname -r); # Kernel version.
File="
/boot/System.map-$ver
/boot/kernel-$ver
/boot/config-$ver
/boot/initrd-1024x768
/etc/X11/XF86Config
/etc/X11/XF86Config.example
/etc/X11/XftConfig
/etc/conf.d/local.start
/etc/dnsdomainname
/etc/gentoo-release
/etc/fstab
/etc/group
/etc/issue
/etc/issue.logo
/etc/make.conf
/etc/motd
/etc/ntp.conf
/etc/passwd
/etc/profile
/etc/rc.conf
/etc/resolv.conf
/etc/sudoers
/usr/X11R6/bin/startx
/var/spool/cron/crontabs/root";

# Whole directories to back-up.
Dirs="
/boot/grub";





# -------------------------------------------------------------------
# - DO NOT EDIT BELOW THIS LINE UNLESS YOU KNOW WHAT YOU ARE DOING! -
# -       I CLAIM NO RESPONSIBILITY FOR ANY OF YOUR MISTAKES!       -
# -------------------------------------------------------------------

version="1.0";
email="agilo3@gmail.com";


# Functions.
domount() {
 umount /boot 2>/dev/null; # Making sure it's umounted.
 mount /boot 2>/dev/null;
 if [ $? != 0 ]; then
  echo "I was unable to mount /boot (is /etc/fstab set up correctly?)." >> ~/$errorlog;
  retval=1;
 else
  umount=1;
 fi
}

dodelete() {
 rm -rf $path/* 2>/dev/null;
 if [ $? != 0 ]; then echo "Could not delete the content of \"$path\"!"; exit 1; fi;
}


# Check to see if the user knows what he is doing.
if [ $UNDERSTOOD == "no" ]; then
 echo -e "\n\nIt seems you have not yet configured this program.";
 echo -e "This program will not work correctly if not set up properly and I" \
         "take no responsibility for any damage caused to you due to misconfiguration!\n\n";
 echo -e "To enable this program, please change \$UNDERSTOOD to \"yes\" in '"$(basename $0)"'\n";
 exit 1;
fi


# Arguments available to the program:
if [ $# -gt 1 ]; then
 echo -e "Too many arguments.\n";
 exit 1;
fi

for i in $1; do
 case "$i" in

  -ym | -my)      # Yes to all questions and mount /boot.
   domount;
   yes=1;;

  -y | --yes)     # Yes to all questions.
   yes=1;;

  -m | --mount)   # Mount /boot.
   domount;;

  -h | --help)    # Show usage.
   echo -e "Usage: $(basename $0) [OPTION]\nMake a backup of important files.\n\n" \
           " -y, --yes\t\tAnswer \"Yes\" to all questions.\n" \
           " -m, --mount\t\tMount /boot.\n" \
           " -h, --help\t\tDisplay this help and exit.\n" \
           " -v, --version\t\tOutput version information and exit.\n" \
           "\n\nBackup utility v$version created by Agilo ($email).";
   exit;;

  -v | --version) # Show version information.
   echo -e "Backup utility version $version.\nCreated by Agilo ($email).\n";
   exit;;

  *)              # Everything else.
   echo -e "Invalid argument!\nSee \"--help\".\n";
   exit;;

 esac
done


# Check if the user is root.
if [ $UID -ne 0 ]; then
 echo -e "You must run $(basename $0) as root.\n";
 exit 1;
fi


# Check if the folder is valid.
if [ $(echo $path | sed -r "s/^\/(.*)\/$/true/") == "true" ]; then            invalid=1; fi
if [ ! -e $path ] && [ ! -d $path ] && [ ! -r $path ] && [ ! -w $path ]; then invalid=1; fi
if [ $invalid ] && [ $invalid == 1 ]; then
 echo -e "Error: the backup directory must be valid (existing and writeable)!\n\n" \
         "\nPlease edit the file '"$(basename $0)"' and change the path \"\$path\" is pointing to.";
 echo -e "Note: there must be no ending slash!\n";
 exit 1;
fi;


# Backup the backup folder's content in a .tar.bz2 file.
echo -e "\n[=] Backing up backup folder's content.";

if [ ! $(tar --version | sed -r "s/^(.*)GNU(.*)$/GNU/") == "GNU" ]; then
 echo -e "Skipping: you must have GNU's 'tar' to create an archive (otherwise; edit this script).\n"
 sleep 3;
else
 mv $path/*.tar.bz2 $tempdir 2>/dev/null
 if [ $(ls $tempdir/backup_`date +'%m%d%Y'`.tar.bz2 2>/dev/null) ] && 
    [ $(ls $tempdir/backup_`date +'%m%d%Y'`.tar.bz2) == "backup_$(date +'%m%d%Y').tar.bz2" ]; then
  rm backup_$(date +'%m%d%Y').tar.bz2 2>/dev/null
  if [ $? != 0 ]; then echo "Unable to delete old backup archive." >> ~/$errorlog; retval=1; fi
 fi
 $(cd $path && tar -cjf $tempdir/backup_$(date +'%m%d%Y').tar.bz2 * 2>/dev/null)
 if [ $? != 0 ]; then echo "Unable to backup the backup folder's content." >> ~/$errorlog; retval=1; else restore=1; fi
fi


# Delete old backup folder content.
echo -ne "\n[-] Deleting old backup folder content.\nContinue? [y/n] ";
if [ $yes ] && [ $yes == "1" ]; then
 echo -n "y";
 dodelete;
else
 read del;
 if [ $del == "y" ]; then
  dodelete;
 else # All other input will result in abort.
  echo -e "\nAborted.\n";
  if [ $umount ] && [ $umount == "1" ]; then umount /boot; fi
  exit;
 fi
fi;


# Copy back old archives from the temporary folder.
if [ $restore ] && [ $restore == "1" ]; then
 mv $tempdir/*.tar.bz2 $path 2>/dev/null
 chmod 700 $path/*.tar.bz2
fi


# Create the directories.
echo -e "\n[=] Creating directories.";
for i in $mkdr; do
 echo "[+] $path/$i";
 mkdir $path/$i >/dev/null 2>>~/$errorlog
 if [ $? != 0 ]; then retval=1; fi;
done


# Copy the directories.
echo -e "\n[=] Copying the directories.";
for i in $Dirs; do
 echo "[>] $i -> $path$(echo $i | awk -F"`basename $i`" '{print $1}')";
 cp -R $i $path$(echo $i | awk -F"`basename $i`" '{print $1}') 2>>~/$errorlog
 if [ $? != 0 ]; then retval=1; fi
done


# Copy the files.
echo -e "\n[=] Copying the files.";
for i in $File; do
 echo "[>] $i -> $path$(echo $i | awk -F"`basename $i`" '{print $1}')";
 cp $i $path$(echo $i | awk -F"`basename $i`" '{print $1}') 2>>~/$errorlog
 if [ $? != 0 ]; then retval=1; fi;
done


# Check if an error has occurd and, if so, notify the user.
if [ $retval ] && [ $retval == "1" ]; then
 echo -e "---\n$(date)\n\n\n\n" >> ~/$errorlog 2>/dev/null;
 echo -e "\n\n\n\nErrors have occurd.  Please see ~/$errorlog\n\n";
 exit 1;
fi


# Done.  Notify user.
echo -e "\nBackup of files completed successfully.\n\n";
if [ $umount ] && [ $umount == "1" ]; then umount /boot; fi