From 187a366fb2442c84879827da0d999298e00bad75 Mon Sep 17 00:00:00 2001
From: Ben Savage <ben@sav.net.au>
Date: Wed, 5 Jun 2019 14:49:03 +1000
Subject: [PATCH] added proper args, help message with argparse, added oneline,
 commented things

---
 stanza | 55 +++++++++++++++++++++++++++++++++++++++++++------------
 1 file changed, 43 insertions(+), 12 deletions(-)

diff --git a/stanza b/stanza
index 7e258c6..e88e051 100755
--- a/stanza
+++ b/stanza
@@ -2,41 +2,72 @@
 
 import sys
 import re
+import argparse
+from pprint import *
 
+# Debug function
+# Setup vars
 buffering=False
 matched=False
 output=''
-start=sys.argv[1]
-match=sys.argv[2]
-end=sys.argv[3]
 
-if len(sys.argv) == 4:
-    handle=sys.stdin
-elif len(sys.argv) == 5:
-    handle=open(sys.argv[4])
+# Setup/parse arguments
+parser = argparse.ArgumentParser(description='Output lines based on complex criteria')
+parser.add_argument('start',help='Regex to start buffering on')
+parser.add_argument('end',help='Regex to close a stanza and output buffer')
+parser.add_argument('-1','--oneline', help='Output each stanza on one line',action='store_true',dest='oneline', default=False)
+parser.add_argument('-d','--debug', help='Debug',action='store_true', default=False)
+parser.add_argument('-m','--match',help='Regex to indicate a valid/desired stanza to output',default='.', action='store',metavar="/r/")
+parser.add_argument('-f','--file',help='File to operate on, defaults to stdin',metavar='FILE',required=False, default=None,dest='filename',action='store')
+args = parser.parse_known_args(sys.argv[1:])
+
+
+# Move namespace into separate var
+cmd=args[0]
+# Set up positional args
+start=cmd.start
+match=cmd.match
+end=cmd.end
 
 def debug(line):
-#    print line
-    pass
+    if cmd.debug:
+	    print line
 
+debug(pformat(args))
+
+# Set up the file handle, <file> or stdin
+if cmd.filename:
+    handle=open(cmd.filename)
+else:
+    handle=sys.stdin
+# Go over the handle, line by line
 for line in handle:
+    # Start buffering if we hit the start regex
     if re.search(start,line):
         buffering=True
         debug('Started buffering on '+start)
     
+    # Continue buffering if we've already started
     if buffering:
         output+=line
 
-    if re.search(match,line):
+    # If a line in the stanza matches, we output the stanza
+    if buffering and re.search(match,line):
         matched=True
         debug('Matched on '+match)
 
-    if re.search(end,line):
+    # Output/clear buffer when we encounter an end to the stanza
+    if re.search(end,line) and buffering==True:
         debug('Finished buffering on '+end)
         if matched:
-            print output
+	    # Strip newlines if requrired
+            if cmd.oneline:
+	            print output.replace("\n",'')
+	    else:
+	            print output
             buffering=False
             matched=False
+	    output=''
         else:
             output=''
             buffering=False