#!/bin/bash

# funcs
set_status(){
   echo "$$" > "$OUTPUT_FILE"
   echo "$1" >> "$OUTPUT_FILE"
}

mount_list(){
   mount |sed -ne "\%^$USB_DEV0[[:digit:]][[:blank:]]%s%[[:blank:]].*$%%p"
}

write_image(){
   set_status "writing"
   for m in $(mount_list) ; do
      umount "$m" || true
   done
   if [ -d "$IMAGE_FILE" ] ; then
      # dir mode
      # create mountpoint
      MOUNT_POINT="$(mktemp -d)"
      mount "$USB_DEV" "$MOUNT_POINT" || return 1
      rsync -rx "$IMAGE_FILE/" "$MOUNT_POINT/" || return 1
      # install syslinux
      # find syslinux file and get syslinux dir
      SYSLINUX_FILE="$(find "$MOUNT_POINT" -name syslinux.cfg -printf "%P\n" 2>/dev/null)"
      SYSLINUX_DIR=""
      if [ "$SYSLINUX_FILE" ] ; then
         SYSLINUX_DIR="$(dirname "$SYSLINUX_FILE")"
      fi
      rm -f "$MOUNT_POINT/$SYSLINUX_DIR/ldlinux.sys"
      [ -z "$SYSLINUX_DIR" ] || SYSLINUX_DIR="-d $SYSLINUX_DIR"
      syslinux $SYSLINUX_DIR "$USB_DEV" || return 1
      # mbr
      cat "$MBR_FILE" > "$USB_DEV0"
#      set_status "cat $MBR_FILE > $USB_DEV0"
#      sleep 5
      # boot
      parted -s "$USB_DEV0" set $USB_PART boot on || true
      umount "$MOUNT_POINT" || true
   else
      # block mode
      # do dd
      dd if="$IMAGE_FILE" of="$USB_DEV" || return 1
   fi
   sleep 1
   for m in $(mount_list) ; do
      umount "$m" || true
   done

   return 0
}

# main

INPUT_FILE="$1"
MBR_FILE="/usr/lib/syslinux/mbr.bin"
[ -r "$MBR_FILE" ] || return 0

while true; do
   [ -s "$INPUT_FILE" ] || exit 0
   USB_DEV="$(sed -ne "1p" "$INPUT_FILE")"
   OUTPUT_FILE="$(sed -ne "2p" "$INPUT_FILE")"
   CONTROL_FILE="$(sed -ne "3p" "$INPUT_FILE")"
   [ "$USB_DEV" -a "$OUTPUT_FILE" -a "$CONTROL_FILE" -a -s "$CONTROL_FILE" ] || exit 0
   USB_DEV0="$(echo "$USB_DEV" |sed -e "s%[[:digit:]]$%%")"
   USB_PART=${USB_DEV##$USB_DEV0}
   IMAGE_FILE="$(sed -ne "1p" "$CONTROL_FILE")"
   [ -r "$IMAGE_FILE" ] || exit 0

   if [ -b "$USB_DEV" ] ; then
      if write_image ; then
         STATUS="COMPLETED. Please, remove USB"
         set_status "$STATUS"
         # wait to remove
         while [ -s "$CONTROL_FILE" -a  -b "$USB_DEV" ] ; do
            sleep 1
         done
         STATUS="iddle"
      else
         STATUS="ERROR"
      fi
   else
      STATUS="iddle"
   fi
   set_status "$STATUS"
   sleep 2
done
exit 0