From afc5ce83393d59aba6868fef4595d4a198ff4455 Mon Sep 17 00:00:00 2001
From: XANTRONIX Development <dev@xantronix.com>
Date: Sun, 5 Jan 2025 23:50:50 -0500
Subject: [PATCH] Comments, improvements

---
 lib/xenu_nntp/mbox.py | 55 +++++++++++++++++++++++++------------------
 1 file changed, 32 insertions(+), 23 deletions(-)

diff --git a/lib/xenu_nntp/mbox.py b/lib/xenu_nntp/mbox.py
index e7a96ea..ca3b966 100644
--- a/lib/xenu_nntp/mbox.py
+++ b/lib/xenu_nntp/mbox.py
@@ -6,32 +6,21 @@ class MBoxReaderError(Exception):
 class MBoxReaderBuffer():
     def __init__(self):
         self.lines = [None, None, None, None]
-        self.index = None
 
     def add(self, line: str):
         if self.lines[0] is None:
             self.lines[0] = line
-            self.index = 0
         elif self.lines[1] is None:
             self.lines[1] = line
-            self.index = 1
         elif self.lines[2] is None:
             self.lines[2] = line
-            self.index = 2
         elif self.lines[3] is None:
             self.lines[3] = line
-            self.index = 3
         else:
             self.lines[0] = self.lines[1]
             self.lines[1] = self.lines[2]
             self.lines[2] = self.lines[3]
             self.lines[3] = line
-            self.index = 3
-
-        if self.index is None:
-            self.index = 0
-        elif self.index < 3:
-            self.index += 1
 
     def is_empty_line(self, line):
         return self.lines[line] == '\n'
@@ -45,7 +34,7 @@ class MBoxReaderBuffer():
     def is_start(self):
         if self.lines[0] is None or self.lines[1] is None:
             return False
-            
+
         if self.is_from_line(0) \
          and self.is_header_line(1) \
          and self.lines[2] is None \
@@ -73,6 +62,9 @@ class MBoxReader():
         while True:
             line = self.fh.readline()
 
+            #
+            # We have reached the final message in the stream.
+            #
             if line is None or line == '':
                 ret = self.message
                 ret.finish()
@@ -85,23 +77,40 @@ class MBoxReader():
 
             self.line += 1
 
+            #
+            # Load the line in the circular mbox state buffer.
+            #
             self.buf.add(line)
 
+            ret = None
+
+            #
+            # If we are at the start of a new message...
+            #
             if self.buf.is_start():
-                if self.message is None:
-                    self.message = Message()
-                    self.message.readline(line)
-                else:
+                if self.message is not None:
+                    #
+                    # If we already have a message, return it.
+                    #
                     ret = self.message
-                    ret.finish()
 
-                    self.message = Message()
-                    self.message.readline(line)
+                #
+                # ...Prepare a new message object.
+                #
+                self.message = Message()
 
-                    return ret
-            else:
-                if self.message:
-                    self.message.readline(line)
+            if self.message is not None:
+                #
+                # Buffer the line into the current message.
+                #
+                self.message.readline(line)
+
+            #
+            # Return the message if we have one.
+            #
+            if ret:
+                ret.finish()
+                return ret
 
     def messages(self):
         while True: