check ISO

#! /bin/bash

## If the original Operative System image is not in the ~/ISOS folder
## or the checksums don't match, download it
## Usage: func_bomsi_check_iso

check_iso () {
  [ "$BASE_ISO_NAME" == "" ] && BASE_ISO_NAME=ubuntu-15.10-server-amd64.iso

  if [[ $BASE_ISO_NAME == "ubuntu"* ]]
    then
      OP_VERSION=$(echo $BASE_ISO_NAME |awk -F"-" '{print $2}')
      URL="http://releases.ubuntu.com"
  else
      echo "ERROR: You have to enter a URL to download $1"
      OP_VERSION=""
      URL=""
      exit
  fi


  [ -z $ISO_DIR_PATH ] && ISO_DIR_PATH=~/ISOS
  [ ! -d $ISO_DIR_PATH ] && mkdir -p $ISO_DIR_PATH


  get_iso () {
  if [ ! -f ${ISO_DIR_PATH}/${BASE_ISO_NAME} ]
    then
      echo ">> No ISO found. Downloading ISO to: ${ISO_DIR}/${ISO_NAME}"
      #curl -s -o ${ISO_DIR_PATH}/${BASE_ISO_NAME} ${URL}/${OP_VERSION}/${BASE_ISO_NAME}
  fi
  }

  get_checksum () {
  if [ ! -f ${ISO_DIR_PATH}/Ubuntu_${OP_VERSION}_MD5SUMS ]
    then
      echo ">> No MD5SUMS found. Downloading file to: ${ISO_DIR_PATH}/Ubuntu_${OP_VERSION}_MD5SUMS"
      curl -s -o ${ISO_DIR_PATH}/Ubuntu_${OP_VERSION}_MD5SUMS \
                 ${URL}/${OP_VERSION}/MD5SUMS
  fi
  }

  get_iso
  get_checksum

  MD5SUM=$(cat ${ISO_DIR_PATH}/Ubuntu_${OP_VERSION}_MD5SUMS |grep ${BASE_ISO_NAME} |awk '{print $1}')

  [ "$MD5SUM" == "" ] && echo "ERROR: probably MDSUMS file is wrong"

  md5sum ${ISO_DIR_PATH}/${BASE_ISO_NAME} |grep -q $MD5SUM || get_iso

  [ "$?" == "0" ] && echo "   > The $BASE_ISO_NAME file is good"

}