#!/bin/bash
# multi partition from one image-file mounter
# 2012 Armas Spann

I_FILE=$1
I_NAME=$(echo $I_FILE | sed -e 's/\./\n/g' | head -1)
B_SIZE=$(/sbin/fdisk -l $I_FILE | grep physical | sed -e 's/\/ /\n/g' | tail -n 1 | sed 's/ bytes//g')

TMP_FILE=$(mktemp)
P_CNT=$#
P_MNT=$2

#creating tempfile:
$(/sbin/fdisk -l $I_FILE | grep $I_NAME | grep -v "$I_FILE:" | sed -e 's/\*/\ /g' > $TMP_FILE)

#checking root privileges
if [[ ${EUID} == 0 ]] ; then
  ROOT=1
else
  ROOT=0
fi

function chkinput {
  if [ $P_CNT -ne 2 ]; then
    howuse
  else
    if [ ! -f $I_FILE ] && [ ! -d $P_MNT ]; then
      echo -e "File or mountpoint not found!"
      quit
    else
      selectpartition
    fi
  fi
}

function howuse {
  echo -e "Usage:"
  echo -e "$0 <image_file> <mount_point>"
  quit
}

function quit {
  rm $TMP_FILE
  unset ROOT
  unset I_FILE
  unset I_NAME
  unset OFFSET
  unset LIMIT
  unset MNT_CMD
  unset what
  unset FS
  unset B_SIZE
  i=0; while [ $i -lt $idx ]; do
    unset P_TABLE[$i]
    i=$(($i+1))
  done
  unset i
  unset idx
  unset P_CNT
  unset P_MNT
  exit
}


#fetching partitions...
idx=0; while read partition; do idx=$(($idx+1));
  if [ "$(echo $partition | awk '{print $5}')" != "82" ]; then
    P_TABLE+=( [$idx-1]="$partition" )
  else
    idx=$(($idx-1))
  fi
done < $TMP_FILE


function selectpartition {
  #output...
  clear
  echo blocksize is: $B_SIZE bytes
  echo found $idx mountable Partitions:
  i=0; while [ $i -lt $idx ]; do
    echo $(($i+1))": ${P_TABLE[$i]}"
    i=$(($i+1))
  done

  #if not root
  if [ "$ROOT" != "1" ]; then
    echo -e "\nSorry u have to be \"root\" to do the mounting stuff..."
    echo -e "ERROR: NO ROOT-ACCESS!"
    quit
  fi

  # select partition
  while :
  do
  read -p "Please choose one of them to mount by number(or 'q' to quit): " -n1 what
  echo -e ""
  case $what in          
    "q") echo -e "Bye... ;-)"; quit
      ;;
    *) if [ $what -gt "0" ] && [ $(($what-1)) -lt $idx ]; then
        TMP_IDX=$(($what-1))
        echo -e "\nYour choice: \n${P_TABLE[TMP_IDX]}"
        read -p "Is this correct? (y/n): " -n1 what
        echo -e "\n"
        if [ $what == "y" ]; then
          OFFSET=$(($(echo ${P_TABLE[TMP_IDX]}|awk '{print $2}')*$B_SIZE))
          LIMIT=$(($(echo ${P_TABLE[TMP_IDX]}|awk '{print $4}')*$B_SIZE))
          read -p "Please enter filesystem (mount option -t): " FS
          MNT_CMD="mount -o loop,ro,offset=$OFFSET,sizelimit=$LIMIT $I_FILE -t $FS $P_MNT"
          mountit
        else
          selectpartition
        fi
      else
        echo -e "Wrong Choice, try again."
        selectpartition
      fi
      ;;
    esac
  done
}

function mountit {
  #should i mount it for you?
  while :
  do
    echo -e "Should i mount it for you? \nCommand: $MNT_CMD"
    read -p "(y/n):" -n1 what
    echo -e ""
    if [ $what == "y" ]; then
      $($MNT_CMD)
      echo -e "Done..."
      quit
    else
      selectpartition
    fi
  done
}

chkinput