diff --git a/hap.py b/hap.py
index 5b0e528..c1e5ff1 100755
--- a/hap.py
+++ b/hap.py
@@ -4,13 +4,16 @@ from kubernetes import client, config
 import sys, random
 
 SVC_TYPE = 'LoadBalancer'
-PORT_COUNT = 1
 
-if len(sys.argv) > 1:
-    try:
-        PORT_COUNT = int(sys.argv[-1])
-    except:
-        sys.exit('optional positional parameter must be a number (default: 1)')
+def getopts():
+        """parse command-line"""
+        from optparse import OptionParser, OptionValueError
+        usage = "%prog [options]"
+        parser = OptionParser(usage=usage)
+        parser.add_option("-n", "--count", type="int", default=1, dest="port_count", help="number of ports needed (default: %default)")
+        return parser.parse_args()
+
+options, args = getopts()
 
 # load client configuration (kubeconfig)
 config.load_kube_config()
@@ -29,4 +32,4 @@ full_port_range = range(49152, 65536) # https://tools.ietf.org/html/rfc6335#sect
 available_ports = list(set(full_port_range) - set(used_ports))
 
 # pick available ports
-print(' '.join(map(str, random.sample(available_ports, PORT_COUNT))))
+print(' '.join(map(str, random.sample(available_ports, options.port_count))))