Add argument parsing

4c

@@ -1,11 +1,34 @@
 #!/usr/bin/python
 
-import re, urllib, urllib2
+import re, urllib, urllib2, argparse, os
+
+parser = argparse.ArgumentParser(description='Downloads all full-size images in an arbitrary 4chan thread.')
+
+parser.add_argument('urllist', metavar='url', type=str, nargs=1,
+                   help='the URL of the thread')
+parser.add_argument('-n', '--newdir', dest='newdir', action='store_true',
+                   help='create a new directory for this thread in the current directory')
+                   
+args = parser.parse_args()
+options = vars(args)
 
 regex = 'href="(\/\/images\.4chan\.org\/b\/src\/[0-9]+\.[a-z]+)"'
-url = 'http://boards.4chan.org/b/res/400860795'
+url = options['urllist'][0]
+
+try:
+	page = urllib2.urlopen(url).read()
+except ValueError:
+	print "That does not look like a valid URL."
+	exit(1)
+
+if options['newdir'] == True:
+	thread_id = url.split('/')[-1]
+	target_dir = "%s/" % thread_id
 
-page = urllib2.urlopen(url).read()
+	if not os.path.exists(thread_id):
+		os.makedirs(thread_id)
+else:
+	target_dir = ""
 
 search = re.compile(regex)
 matches = search.finditer(page)
@@ -24,6 +47,7 @@ print "Parsed thread. Total images: %d" % total
 for downloadurl in urls:
 	downloadurl = "http:%s" % downloadurl
 	filename = downloadurl.split('/')[-1]
-	urllib.urlretrieve(downloadurl, filename)
+	path = target_dir + filename
+	urllib.urlretrieve(downloadurl, path)
 	print "Downloaded %s (%d/%d)." % (filename, current, total)
 	current += 1