contrib/highlight

   1 #!/usr/bin/python3
   2
   3 import sys
   4
   5 def parse(line): #-> [nick, user, host], command, arguments
   6     prefix, params  = b"", []
   7     command, arguments = None, []
   8     nick, user, host = None, None, None
   9
  10     line = line.rstrip(b"\r\n")
  11     # handle prefix:
  12     if line.startswith(b":"):
  13         prefix, line = line.split(b" ", 1)
  14     # handle command and arguments:
  15     while b" " in line and not line.startswith(b":"):
  16         word, line = line.split(b" ", 1)
  17         params += [word]
  18     # handle final parameter:
  19     params += [line.removeprefix(b":")]
  20
  21     if params:
  22         # note: command may also be a numeric reply
  23         command, *arguments = params
  24
  25     if b"!" in prefix and b"@" in prefix:
  26         nick, rest = prefix.removeprefix(b":").split(b"!", 1)
  27         user, host = rest.split(b"@", 1)
  28     elif prefix: # server
  29         host = prefix.removeprefix(b":")
  30
  31     return [nick, user, host], command, arguments
  32
  33 DIM = b"\033[0;2m"
  34 BOLD = b"\033[0;1m"
  35 RESET = b"\033[0m"
  36 REV = b"\033[0;7m"
  37
  38 def say(*args):
  39     sys.stdout.buffer.write(b"".join(args)+b"\n")
  40     sys.stdout.buffer.flush()
  41
  42 def findall(needle, haystack):
  43     if not needle: return []
  44     spans, offset, length = [], 0, len(needle)
  45     nickchars = (
  46         br"ABCDEFGHIJKLMNOPQRSTUVWXYZ"
  47         br"abcdefghijklmnopqrstuvwxyz"
  48         br"0123456789-[\]^_`{|}")
  49
  50     while offset < len(haystack):
  51         try:
  52             offset = haystack.index(needle, offset)
  53             # check for a word boundary before and after nick:
  54             if (offset==0 or haystack[offset-1] not in nickchars) \
  55             and (offset+length==len(haystack) or haystack[offset+length] not in nickchars):
  56                 spans += [(offset, length)]
  57             offset += length
  58         except ValueError as e:
  59             break # no more matches
  60     return spans
  61
  62 myself = None
  63 for line in sys.stdin.buffer:
  64     [nick, user, host], command, arguments = parse(line)
  65
  66     if command in (b"PRIVMSG", b"NOTICE") and len(arguments) == 2 and nick:
  67         chan, msg = arguments
  68         nick_start = len(b":")
  69         nick_end = nick_start+len(nick)
  70         cmd_start = nick_end+len(b"!")+len(user)+len(b"@")+len(host)+len(b" ")
  71         cmd_end = cmd_start+len(command)
  72         chan_start = cmd_end+len(b" ")
  73         chan_end = chan_start+len(chan)
  74         msg_start = chan_end+len(b" ")
  75         msg_end = msg_start+len(msg)
  76         if line[msg_start] == ord(':'):
  77             msg_start +=1
  78             msg_end +=1
  79
  80         hi_msg = line[msg_start:msg_end]
  81         for s,l in reversed(findall(myself, hi_msg)):
  82             hi_msg = hi_msg[:s] + REV + hi_msg[s:s+l] + RESET + hi_msg[s+l:]
  83
  84         # maybe todo:
  85         # - support mIRC highlighting (colors, bold, etc)
  86         #   https://modern.ircdocs.horse/formatting.html
  87         #   including \x01ACTION privmsg prefix
  88         # - highlight own nick and/or user-def'd strings
  89
  90         say(
  91             DIM,   line[:nick_start],
  92             BOLD,  line[nick_start:nick_end],
  93             DIM,   line[nick_end:chan_start],
  94             BOLD,  line[chan_start:chan_end],
  95             DIM,   line[chan_end:msg_start],
  96             RESET, hi_msg,
  97             REV,   line[msg_end:].rstrip(b"\r\n"),
  98         RESET)
  99     elif command in (b"PING", b"PONG"):
 100         pass # hide (could also do "JOIN", "QUIT", motd, names, ...)
 101     else:
 102         if command == b"001" and arguments:
 103             myself = arguments[0] # store own username for later highlighting it
 104         say(
 105             DIM,   line.rstrip(b"\r\n"),
 106         RESET)