#!/bin/csh
#
# scrypto
# some shell based crypto by Michael L. Love (GPL) 
# Wed Sep  5 14:42:02 EDT 2007
#


date --version  > /dev/null
if ( $? != 0 ) then
	echo this only works with GNU date
	exit
endif

#setenv SEED `date +%N | cut -b1-6 | sed s/'$'/'\/999999'/ | sed s/^/'scale=214748364\n'/ | bc`
setenv SEED `date +%N | cut -b1-6 | sed s/'$'/'\/999999'/ | sed s/^/'scale=22\n'/|bc`

echo the seed is $SEED


setenv ARRAY ${1}
setenv WIDTH `echo 'sqrt ('${1}')' | sed s/^/'scale=22\n'/ | bc | cut -f1 -d'.'`

echo the array size is $ARRAY
echo the width size is $WIDTH

setenv SEEDARRAY `echo ${SEED}'*'${1} | sed s/^/'scale=22\n'/ | bc | cut -f1 -d'.'`
echo the seed array size is $SEEDARRAY

#seq 1 ${1} | rs | rs -t ${ARRAY} | tac | rs 1 | rs | rs -t ${SEEDARRAY} | tac | s 1 | rs | rs 10

seq 1 ${1} | rs | rs -t ${SEEDARRAY} | tac | rs 1  |\
	     rs | rs -t 4            | tac | rs 10 |\
	     rs | rs -t 51           | tac | rs 7  |\
	     rs | rs -t 101          | tac | rs 13 |\
	     rs | rs -t 213          | tac | rs 17 |\
	     rs | rs -t ${WIDTH}     | tac | rs 29 |\
	     rs

# this well meaning attempt to scale the algorythm only introduced systematic waves
#setenv WIDTH `echo ${1}'*4' | sed s/^/'scale=22\n'/ | bc`
# seq 1 ${1} | rs -w${WIDTH} | rs -w${WIDTH} -t ${ARRAY} | tac | rs -w${WIDTH} 1 | rs -w${WIDTH} | rs -w${WIDTH} -t ${SEEDARRAY} | tac | rs -w${WIDTH} 1 | rs -w${WIDTH} | rs -w${WIDTH} 10