################################
## Additional Shell Functions ##
## By: Thiam H Lee            ##
## Last Updated: Jun 29 2009  ##
################################

## Find a file with a regular expression pattern in name:
findfile () {
  if [ $# -eq 0 ]; then
    echo "findfile: Runs the find command with the given regular expression.";
    echo "";
    echo "Usage: findfile <regex>";
    echo "";
    echo "Example: findfile '.*\.txt'";
    echo "         searches the directory tree rooted at the current directory";
    echo "         for all files ending with '.txt'";
    echo ""
    return 1
  fi
  if [ $# -ne 1 ]; then
    echo "findfile: Exactly 1 argument is required";
    return 1
  fi

  find . -type f -regex $* -ls;
}

## Find filenames with regular expression pattern $1 and run $2 on it:
findfileandrun () {
  if [ $# -eq 0 ]; then
    echo "findfileandrun: Executes the find command with the given regular expression";
    echo "                and runs the given command on each of the matches";
    echo "";
    echo "Usage: findfileandrun <regex> <command-to-run>";
    echo "";
    echo "Example: findfile '.*\.txt' cat";
    echo "         searches the directory tree rooted at the current directory";
    echo "         for all files ending with '.txt' and runs the command 'cat'";
    echo "         on each matched file.";
    echo ""
    return 1
  fi
  if [ $# -ne 2 ]; then
    echo "findfile: Exactly 2 arguments are required";
    return 1
  fi

  find . -type f -regex $1 -exec "${2:-file}" {} \;  ;
}

## Get host info
hostinfo () {
  echo -e "\nHostname: $HOST"
  echo -e "\nAdditionnal information: " ; uname -a
  echo -e "\nUsers logged on: " ; w -h
  echo -e "\nCurrent date : " ; date
  echo -e "\nMachine stats : " ; uptime
  echo -e "\nMemory stats : " ; free
  echo
}

## Encode/Decode rot13 messages
rot13 () {
  if [ $# -eq 0 ]; then
    tr '[a-m][n-z][A-M][N-Z]' '[n-z][a-m][N-Z][A-M]'
  else
    echo $* | tr '[a-m][n-z][A-M][N-Z]' '[n-z][a-m][N-Z][A-M]'
  fi
}

## Compress files
roll () {
  if [ $# -eq 0 ]; then
    echo "roll: Compress files";
    echo "";
    echo "Usage: roll [compressed-file] [files ...]";
    echo "Supported compression formats: .tar .tar.bz2 .tar.gz .tbz .tgz .zip";
    echo "";
    echo "Example: roll example.tar.gz file1 file2 file3";
    echo "         compresses file1, file2 and file3 -> example.tar.gz";
    echo ""
    return 1
  fi

  FILE=$1
  case $FILE in
    *.tar)	shift && tar cvf $FILE $* ;;
    *.tar.bz2)	shift && tar cvjf $FILE $* ;;
    *.tar.gz)	shift && tar cvzf $FILE $* ;;
    *.tbz)	shift && tar cvjf $FILE $* ;;
    *.tgz)	shift && tar cvzf $FILE $* ;;
    *.zip)	shift && zip -r $FILE $* ;;
    *)		echo "${FILE} : Unsupported compression format" ;;
  esac
}

## Swap two files
swap () {
  if [ $# -ne 2 ]; then
    echo "swap: 2 arguments needed"; return 1
  fi

  if [ ! -w $1 ]; then
    echo "swap: $1 does not exist or is not writable"; return 1
  fi

  if [ ! -w $2 ]; then
    echo "swap: $2 does not exist or is not writable"; return 1
  fi

  local TMPFILE=tmp.$$ ; mv $1 $TMPFILE ; mv $2 $1 ; mv $TMPFILE $2
}

## Uncompress file
unroll () {
  if [ $# -eq 0 -o $# -ge 2 ]; then
    echo "unroll: Uncompress file to the present working directory";
    echo "";
    echo "Usage: unroll [compressed-file]";
    echo "Supported formats: .bz2 .gz .rar .tar .tar.bz2 .tar.gz .tbz .tgz .zip";
    echo "";
    echo "Example: unroll example.tar.gz";
    echo "         uncompresses example.tar.gz into the";
    echo "         present working directory.";
    echo "";
    return 1
  fi

  FILE=$1
  if [ -f $FILE ]; then
    case $1 in
      *.rar)		unrar x $FILE ;;
      *.tar)		tar xvf $FILE ;;
      *.tar.bz2)	tar xvjf $FILE ;;
      *.tar.gz)		tar xvzf $FILE ;;
      *.bz2)		bunzip2 $FILE ;;
      *.gz)		gunzip $FILE ;;
      *.tbz)		tar xvjf $FILE ;;
      *.tgz)		tar xvzf $FILE ;;
      *.zip)		unzip $FILE ;;
      *)		echo "$FILE : Unsupported compression format" ;;
    esac
  else
    echo "$FILE does not exist or is not a valid file"
  fi
}