#!/usr/bin/python2
#
# nbcalc is a netblock calculator: you give it netblocks or facsimiles
# thereof, it adds (or subtracts) them together, and finishes off by
# spitting out the resulting netblock(s).
import sys
sys.path.insert(1, "/u/cks/share/python")

# look ma, netblock caculations:
import netblock

def die(str):
	sys.stderr.write(sys.argv[0] + ': ' + str + '\n')
	sys.exit(1)
def warn(str):
	sys.stderr.write(sys.argv[0] + ': ' + str + '\n')

def dumpout(r):
	res = r.tocidr()
	if len(res) > 0:
		print "\n".join(res)

def process(args):
	r = netblock.IPRanges()

	# people's republic of glorious special cases.
	if len(args) == 3 and args[1] == "-":
		process(["%s-%s" % (args[0], args[2]),])
		return

	# We permit the rarely used calculator mode.
	opd = r.add
	for a in args:
		op = opd
		# Are we changing the operation?
		if a == "-":
			opd = r.remove
			continue
		elif a == "+":
			opd = r.add
			continue
		# We might be asking for a one-shot subtraction.
		if a[0] == '-':
			op = r.remove
			a = a[1:]
		# We notice bad input by the errors that netblock throws.
		try:
			op(a)
		except netblock.BadCIDRError, e:
			# Because this happens SO OFTEN, give a specific
			# message.
			c = netblock.convcidr(a, 0)
			die("bad CIDR %s. Should start at IP %s" % \
			    (a, netblock.ipstr(c[0])))
		except netblock.NBError, e:
			die("bad argument %s: %s" % (a, str(e)))
	dumpout(r)

#import profile
if __name__ == "__main__":
	#profile.run('process(sys.argv[1:])')
	process(sys.argv[1:])