#!/bin/bash

# check_nrid.sh
# - filters invalid nric in student list csv file for unidata
# - assume input is list.csv
# - run 'bash check_nric.sh list.csv >/dev/null' to check
# - if nothing comes out, then the file is good
# - run 'bash check_nrid.sh list.csv > list1.csv 2>/dev/null'
# - will get fixed data in list1.csv

check_nrid()
{
	local file loop line stid name nrid prog look prev
	file=$1
        [ ! -f $file ] && exit 0
	loop=0
	while read line ; do
		if [ $loop -gt 0 ] ; then
			stid=$(echo $line|cut -d',' -f1)
			name=$(echo $line|cut -d',' -f2)
			nrid=$(echo $line|cut -d',' -f3)
			prog=$(echo $line|cut -d',' -f4)
			look=0 prev=$nrid
			while [ ${#nrid} -ne 12 ] ; do
				nrid="0$nrid"
				look=1
			done
			# trim prog
			prog=${prog% }
			line="$stid,$name,$nrid,$prog,,,"
			if [ $look -ne 0 ] ; then
				echo "** [$prev] $line" >&2
			else
				echo "$line"
			fi
		fi
		((loop++))
	done < $file
}
check_nrid $@