#!/bin/bash

export PATH="$PATH:/sbin:/usr/sbin"

usage () {
    echo -e "Usage:\t$0 -c -i <IMAGE FILE> -d <DATA DIR> [ -s <SIZE> ] [ -f <FS TYPE> ] [ -t <IMAGE TYPE> ] [ -u <OWNER> ]"
    echo -e "\t\t-e -i <IMAGE FILE> -d <DATA DIR> [ -b <BASE PATH> ] [ -u <OWNER> ]"
    exit 1
}

create_disk_img () {
    local datadir=$1
    local imgfile=$2
    local imgsize=$3
    local fstype=$4
    local imgtype=$5
    [ -z "$imgsize" ] && imgsize="100G"
    [ -n "$fstype" -a "$fstype" != "vfat" ] && \
        echo -e "WARNING: Only VFAT images are supported by Rainbow essentials.\n"\
                "        Enable libguestfs support for ${fstype}.\n"\
                "        Forcing VFAT file system type."
    # Create qcow2 image: qemu-img create -f qcow2 -o cluster_size=2M,preallocation=metadata $image 100G
    # To mount qcow2 image qemu-nbd is needed, but Qemu in RHEL6 is missing support of this feature
    # So Rainbow basic image operations method will support RAW images only
    [ -n "$imgtype" -a "$imgtype" != "raw" ] && \
        echo -e "WARNING: Only RAW images are supported by Rainbow essentials. \n"\
                "        Enable libguestfs support for ${imgtype}.\n"\
                "        Forcing RAW image format.\n"
    imgtype="raw"
    fstype="vfat"

    qemu-img create -f $imgtype $imgfile $imgsize
    # windows wants the partition on disk
    parted -s $imgfile mklabel msdos
    parted -a opt -s -- $imgfile mkpart primary fat32 0 -0
    part_offset=$( parted -s $imgfile unit B print | sed -n 's/\s*1\s*\([0-9]\+\)B\s*[0-9]\+B.*/\1/p' )
    #
    # this part requeres root proveledges
    #
    loopdev=$( losetup -f --show -o $part_offset $imgfile )
      if [ "$fstype" = "vfat" ]; then
          # TODO: ext3 support?
          mkdosfs -F32 -n DATA $loopdev
      fi
      mountpoint="${datadir}-img"
      mkdir -p $mountpoint
        mount -t vfat $loopdev $mountpoint
          cp -r ${datadir}/* $mountpoint
        umount $loopdev
      rmdir $mountpoint
    losetup -d $loopdev
}

extract_disk_img () {
    local imgfile=$1
    local datadir=$2
    local basepath=$3

    part_offset=$( parted -s $imgfile unit B print | sed -n 's/\s*1\s*\([0-9]\+\)B\s*[0-9]\+B.*/\1/p' )
    loopdev=$( losetup -f --show -o $part_offset $imgfile )
      mountpoint="${datadir}-img"
      mkdir -p $mountpoint
      mkdir -p $datadir
        mount $loopdev $mountpoint
          ls ${mountpoint}/${basepath} >/dev/null 2>&1
          [ $? -eq 0 ] && cp -r ${mountpoint}/${basepath}/* $datadir || echo "Base path does not exist. Extraction failed."
        umount $loopdev
      rmdir $mountpoint
    losetup -d $loopdev
}

[ $# -eq 0 ] && usage

# parse options
while getopts ":cei:d:s:f:t:u:b:" opt; do
  case $opt in
    c)
      createimg=1
      ;;
    e)
      extractimg=1
      ;;
    i)
      imgfile="$OPTARG"
      ;;
    d)
      datadir="$OPTARG"
      ;;
    s)
      imgsize="$OPTARG"
      ;;
    f)
      fstype="$OPTARG"
      ;;
    t)
      imgtype="$OPTARG"
      ;;
    u)
      owner="$OPTARG"
      ;;
    b)
      basepath="$OPTARG"
      ;;
    \?)
      usage
      ;;
    :)
      echo "Option -$OPTARG requires an argument." >&2
      usage
      ;;
  esac
done


if [ -n "$createimg" ]; then
    [ -n "$extractimg" ] && usage
    [ ! -d "$datadir" ] && usage
    [ -z "$imgfile" ] && usage
    exec 1>&2
    create_disk_img "$datadir" "$imgfile" $imgsize $fstype $imgtype
    [ -n "$owner" ] && chown "$owner" "$imgfile"
elif [ -n "$extractimg" ]; then
    [ ! -f "$imgfile" ] && usage
    [ -z "$datadir" ] && usage
    exec 1>&2
    extract_disk_img "$imgfile" "$datadir" "$basepath"
     [ -n "$owner" ] && chown -R "$owner" "$datadir" 
else
    usage
fi