"""irclog -- an IRC log beautifier for the Trac wiki""" 

# Copyright (c) 2005, Simon E. Ward
# Copyright (c) 2005, Marius Gedminas 
# Copyright (c) 2000, Jeffrey W. Waugh

# Trac Wiki-Processor:
#   Simon Ward <simon@mivok.net>
# Python port:
#   Marius Gedminas <marius@pov.lt>
# Original Author:
#   Jeff Waugh <jdub@perkypants.org>
# Contributors:
#   Rick Welykochy <rick@praxis.com.au>
#   Alexander Else <aelse@uu.net>
#
# Released under the terms of the GNU GPL
# http://www.gnu.org/copyleft/gpl.html

import re
from StringIO import StringIO

IRCLOG2HTML_VERSION = "2.3"
IRCLOG2HTML_RELEASE = "2005-03-28"

URL_REGEXP = re.compile(r'((http|https|ftp|gopher|news)://[^ \'")>]*)')

def createlinks(text):
    """Replace possible URLs with links."""
    return URL_REGEXP.sub(r'<a href="\1">\1</a>', text)

def escape(s):
    """Replace ampersands, pointies, control characters.

        >>> escape('Hello & <world>')
        'Hello &amp; &lt;world&gt;'
        >>> escape('Hello & <world>')
        'Hello &amp; &lt;world&gt;'

    Control characters (ASCII 0 to 31) are stripped away

        >>> escape(''.join([chr(x) for x in range(32)]))
        ''

    """
    s = s.replace('&', '&amp;').replace('<', '&lt;').replace('>', '&gt;')
    return ''.join([c for c in s if ord(c) > 0x1F])

def shorttime(time):
    """Strip date and seconds from time.

        >>> shorttime('12:45:17')
        '12:45'
        >>> shorttime('12:45')
        '12:45'
        >>> shorttime('2005-02-04T12:45')
        '12:45'

    """
    if 'T' in time:
        time = time.split('T')[-1]
    elif ' ' in time:
        time = time.split(' ')[-1]
    if time.count(':') > 1:
        time = ':'.join(time.split(':')[:2])
    return time


class Enum(object):
    """Enumerated value."""

    def __init__(self, value):
        self.value = value

    def __repr__(self):
        return self.value


class LogParser(object):
    """Parse an IRC log file.

    When iterated, yields the following events:

        time, COMMENT, (nick, text)
        time, ACTION, text
        time, JOIN, text
        time, PART, text,
        time, NICKCHANGE, (text, oldnick, newnick)
        time, SERVER, text

    """

    COMMENT = Enum('COMMENT')
    ACTION = Enum('ACTION')
    JOIN = Enum('JOIN')
    PART = Enum('PART')
    NICKCHANGE = Enum('NICKCHANGE')
    SERVER = Enum('SERVER')
    OTHER = Enum('OTHER')

    TIME_REGEXP = re.compile(
            r'^\[?(' # Optional [
            r'(?:\d{4}-\d{2}-\d{2}T|\d{2}-\w{3}-\d{4} |\w{3} \d{2} )?'
                # Optional date
            r'\d\d:\d\d(:\d\d)?' # Mandatory HH:MM, optional :SS
            r')\]? +') # Optional ], mandatory space
    NICK_REGEXP = re.compile(r'^(?:<(.*?)>|([a-zA-Z\[\\\]^_`{|}][a-zA-Z0-9\[\\\]^_`{|}-]+))\s')
    JOIN_REGEXP = re.compile(r'^(?:\*\*\*|-->)\s.*joined')
    PART_REGEXP = re.compile(r'^(?:\*\*\*|<--)\s.*(quit|left)')
    SERVMSG_REGEXP = re.compile(r'^(?:\*\*\*|---)\s')
    NICK_CHANGE_REGEXP = re.compile(
            r'^(?:\*\*\*|---)\s+(.*?) (?:are|is) now known as (.*)')

    def __init__(self, infile):
        self.infile = infile

    def __iter__(self):
        for line in self.infile:
            line = line.rstrip('\r\n')
            if not line:
                continue

            m = self.TIME_REGEXP.match(line)
            if m:
                time = m.group(1)
                line = line[len(m.group(0)):]
            else:
                time = None

            m = self.NICK_REGEXP.match(line)
            if m:
                nick = m.group(1) or m.group(2)
                text = line[len(m.group(0)):]
                yield time, self.COMMENT, (nick, text)
            elif line.startswith('* ') or line.startswith('*\t'):
                yield time, self.ACTION, line
            elif self.JOIN_REGEXP.match(line):
                yield time, self.JOIN, line
            elif self.PART_REGEXP.match(line):
                yield time, self.PART, line
            else:
                m = self.NICK_CHANGE_REGEXP.match(line)
                if m:
                    oldnick = m.group(1)
                    newnick = m.group(2)
                    yield time, self.NICKCHANGE, (line, oldnick, newnick)
                elif self.SERVMSG_REGEXP.match(line):
                    yield time, self.SERVER, line
                else:
                    yield time, self.OTHER, line


class NickClassifier(object):
    """Assign style classes to nicknames."""

    def __init__(self, maxclasses=30, default_classes=None):
        self.nickcount = 0
        self.maxclasses = maxclasses
        self.nick_classes = {}
        if default_classes:
            self.nick_classes.update(default_classes)

    def __getitem__(self, nick):
        cls = self.nick_classes.get(nick)
        if not cls:
            self.nickcount += 1
            fieldlen = len(str(self.maxclasses))
            cls = ('nc%%0%dd' % fieldlen) % (self.nickcount % self.maxclasses)
            self.nick_classes[nick] = cls
        return cls

    def change(self, oldnick, newnick):
        if oldnick in self.nick_classes:
            self.nick_classes[newnick] = self.nick_classes.pop(oldnick)


class AbstractStyle(object):
    """A style defines the way output is formatted.

    This is not a real class, rather it is an description of how style
    classes should be written.
    """

    name = "stylename"
    description = "Single-line description"

    def __init__(self, outfile, classes=None):
        """Create a text formatter for writing to outfile.

        `classes` may have the following attributes:
           part
           join
           server
           nickchange
           action
        """
        self.outfile = outfile
        self.classes = classes or {}

    def servermsg(self, time, what, line):
        """Output a generic server message.

        `time` is a string.
        `line` is not escaped.
        `what` is one of LogParser event constants (e.g. LogParser.JOIN).
        """

    def nicktext(self, time, nick, text, htmlclass):
        """Output a comment uttered by someone.

        `time` is a string.
        `nick` and `text` are not escaped.
        `htmlclass` is a string.
        """


class XHTMLStyle(AbstractStyle):
    """Text style, produces XHTML that can be styled with CSS"""

    name = 'xhtml'
    description = __doc__

    CLASSMAP = {
        LogParser.ACTION: 'action',
        LogParser.JOIN: 'join',
        LogParser.PART: 'part',
        LogParser.NICKCHANGE: 'nickchange',
        LogParser.SERVER: 'servermsg',
        LogParser.OTHER: 'other',
    }

    prefix = '<div class="irclog">'
    suffix = """</div>
<div class="generatedby">
<p>Generated by irclog wiki-processor
 (<a href="mailto:simon@mivok.net">Simon Ward</a>),
 based on irclog2html.py %(VERSION)s by 
 <a href="mailto:marius@pov.lt">Marius Gedminas</a>
 - find it at <a href="http://mg.pov.lt/irclog2html/">mg.pov.lt</a>!</p>
</div> """ % { 'VERSION': IRCLOG2HTML_VERSION }

    def link(self, url, title):
        # Intentionally not escaping title so that &entities; work
        if url:
            print >> self.outfile, ('<a href="%s">%s</a>'
                                    % (escape(urllib.quote(url)),
                                       title or escape(url))),
        elif title:
            print >> self.outfile, ('<span class="disabled">%s</span>'
                                    % title),

    def servermsg(self, time, what, text):
        """Output a generic server message.

        `time` is a string.
        `line` is not escaped.
        `what` is one of LogParser event constants (e.g. LogParser.JOIN).
        """
        text = escape(text)
        text = createlinks(text)
        if time:
            displaytime = shorttime(time)
            print >> self.outfile, ('<p id="t%s" class="%s">'
                                    '<a href="#t%s" class="time">%s</a> '
                                    '%s</p>'
                                    % (time, self.CLASSMAP[what], time,
                                       displaytime, text))
        else:
            print >> self.outfile, ('<p class="%s">%s</p>'
                                    % (self.CLASSMAP[what], text))

    def nicktext(self, time, nick, text, htmlclass):
        """Output a comment uttered by someone.

        `time` is a string.
        `nick` and `text` are not escaped.
        `htmlclass` is a string.
        """
        nick = escape(nick)
        text = escape(text)
        text = createlinks(text)
        text = text.replace('  ', '&nbsp;&nbsp;')
        if time:
            displaytime = shorttime(time)
            print >> self.outfile, ('<p id="t%s" class="comment %s">'
                                    '<a href="#t%s" class="time">%s</a> '
                                    '<span class="nick">&lt;%s&gt;</span>'
                                    ' <span class="text">%s</span></p>'
                                    % (time, htmlclass, time, displaytime,
                                       nick, text))
        else:
            print >> self.outfile, ('<p class="comment %s">'
                                    '<span class="nick">&lt;%s&gt;</span>'
                                    ' <span class="text">%s</span></p>'
                                    % (htmlclass, nick, text))


class XHTMLTableStyle(XHTMLStyle):
    """Table style, produces XHTML that can be styled with CSS"""

    name = 'xhtmltable'
    description = __doc__

    prefix = '<table class="irclog">'
    suffix = '</table>'

    def servermsg(self, time, what, text):
        text = escape(text)
        text = createlinks(text)
        if time:
            displaytime = shorttime(time)
            print >> self.outfile, ('<tr id="t%s">'
                                    '<td class="%s" colspan="2">%s</td>'
                                    '<td><a href="#t%s" class="time">%s</a></td>'
                                    '</tr>'
                                    % (time, self.CLASSMAP[what], text,
                                       time, displaytime))
        else:
            print >> self.outfile, ('<tr>'
                                    '<td class="%s" colspan="3">%s</td>'
                                    '</tr>'
                                    % (self.CLASSMAP[what], text))

    def nicktext(self, time, nick, text, htmlclass):
        nick = escape(nick)
        text = escape(text)
        text = createlinks(text)
        text = text.replace('  ', '&nbsp;&nbsp;')
        if time:
            displaytime = shorttime(time)
            print >> self.outfile, ('<tr class="%s" id="t%s">'
                                    '<th class="nick">%s</th>'
                                    '<td class="text">%s</td>'
                                    '<td class="time">'
                                    '<a href="#t%s" class="time">%s</a></td>'
                                    '</tr>'
                                    % (htmlclass, time, nick, text,
                                       time, displaytime))
        else:
            print >> self.outfile, ('<tr class="%s">'
                                    '<th class="nick">%s</th>'
                                    '<td class="text" colspan="2">%s</td>'
                                    '</tr>' % (htmlclass, nick, text))


def execute(hdf, text, env):
    textbuf = StringIO(text)
    htmlbuf = StringIO()

    parser = LogParser(textbuf)
    formatter = XHTMLTableStyle(htmlbuf)
    nick_classes = NickClassifier(maxclasses=20)
    htmlbuf.write(formatter.prefix)
    for time, what, info in parser:
        if what == LogParser.COMMENT:
            nick, text = info
            nickclass = nick_classes[nick]
            formatter.nicktext(time, nick, text, nickclass)
        else:
            if what == LogParser.NICKCHANGE:
                text, oldnick, newnick = info
                nick_classes.change(oldnick, newnick)
            else:
                text = info
            formatter.servermsg(time, what, text)

    # Footer
    htmlbuf.write(formatter.suffix)
    return htmlbuf.getvalue()