#!/usr/bin/env python3
'whits.py - by Sean B. Palmer'

import sys, os, re, time, getopt
import irc3, stream

title = 'Gallimaufry of Whits'
uri = 'http://inamidst.com/whits/'
tag = 'tag:inamidst.com,2006:whits'
author = 'Sean B. Palmer'
nick = 'sbp'
botnick = 'whitsbot'
server = 'irc.freenode.net'
channel = '#whits'
os.chdir('/Users/sbp/web/inamidst.com/www/whits')

def process(text): 
   separator = text == '%%'
   replacement = text.startswith('sub: ')
   regular = not (separator or replacement)

   if regular: 
      add_to_homepage(text)
   elif separator: 
      entry = create_homepage_entry()
      add_to_feed(entry)
   elif replacement: 
      substitute_item(text)

def nextlabel(line): 
   if not 'class="' in line: 
      return 'a'

   a, b = line.split('class="', 1)
   prior = b.split('"', 1)[0]

   def next(label): 
      if label.endswith('z'): 
         return next(label[:-1]) + 'a'
      else: return label[:-1] + chr(ord(label[-1]) + 1)
   return next(prior)

def hypertext(text, label): 
   r_hyperlink = re.compile(r'\{([^}]+) (http://[^ }]+)\}')
   text = r_hyperlink.sub(r'<a href="\g<2>">\g<1></a>', text)
   return '<p class="%s">%s</p>' % (label, text)

def add_to_homepage(text): 
   with stream.Stream('index.html') as index: 
      def create(text): 
         index.write('<div title="%s">' % strftime('%d %B %Y'))
         index.write(hypertext(text, 'a'))
         index.write('</div>')
         index.write('')
         ui.notify('Published {a} to new homepage entry')

      if index.before('1st', '<div'): 
         if 'class="entry"' in index.next: 
            create(text)
            return True

      if index.before('1st', '</div>'): 
         label = nextlabel(index.previous)
         index.write(hypertext(text, label))
         ui.notify('Published {%s} to homepage' % label)
         return True
      else: create(text)

def substitute_item(text): 
   line = text[5:] # strip off the leading "sub: "
   try: label, value = line.split(': ', 1)
   except Exception as err: 
      ui.notify('Error: ' + str(err))
      return

   with stream.Stream('index.html') as index: 
      if index.instead('1st', 'class="%s"' % label): 
         index.write(hypertext(value, label))
         ui.notify('Substituted new value for {%s}' % label)

def create_homepage_entry(): 
   with stream.Stream('index.html') as index: 
      if index.instead('1st', '<div'): 
         previous = index.previous.rstrip('\r\n')
         if ('class="entry"' in previous) or ('</div>' in index.next): 
            index.write(previous)
            return None

         index.collect()
         div = previous.replace('<div', '<div class="entry"')
         index.write(div)
         ui.notify('Created homepage entry')

      if index.after('1st', '</div>'): 
         entry = index.collected()
      else: raise ValueError()
   return entry

def strftime(format): 
   return time.strftime(format, time.gmtime())

def cdata(markup): 
   markup = ''.join(markup)
   return '<![CDATA[' + markup.replace(']]>', ']]>]]><![CDATA[') + ']]>'

def add_to_feed(entry): 
   if entry is None: 
      ui.notify('No entry to add')
      return False

   now = strftime('%Y-%m-%dT%H:%M:%SZ')
   with stream.Stream('feed.atom') as feed: 
      def create(feed, entry): 
         feed.write(' <entry xml:base="%s">' % uri)
         feed.write('  <id>%s:%s</id>' % (tag, now))
         feed.write('  <link rel="alternate" type="text/html" href="%s"/>' % uri)
         feed.write('  <title>%s</title>' % strftime('%d %B %Y %H:%M'))
         feed.write('  <updated>%s</updated>' % now)
         feed.write('  <author><name>%s</name></author>' % author)
         feed.write('  <content type="html">')
         feed.write(cdata(entry))
         feed.write('  </content>')
         feed.write(' </entry>')
         ui.notify('Created feed entry')

      created = False
      if feed.instead('1st', '<updated>'): 
         feed.write(' <updated>%s</updated>' % now)
         if '</feed>' in feed.next: 
            create(feed, entry)
            created = True

      if feed.before('1st', '<entry') and (not created): 
         create(feed, entry)

      if feed.after('9th', '</entry>'): 
         feed.write('</feed>')
         feed.close()

def utf8(arg): 
   return str(arg).encode('utf-8')

class WhitsClient(irc3.Client): 
   def dispatch(self, command, sender, *args): 
      print(utf8(command), utf8(sender), utf8(args))

      if (command == '251'): 
         self.join(channel)
         self.msg(channel, '-- %s --' % title)

      elif (command == 'PRIVMSG'): 
         recipient, text = args
         if not sender.startswith(nick + '!'): return
         if not recipient.startswith('#'): return
         process(text)

   def notify(self, message): 
      self.msg(channel, message)

def irc(): 
   global ui
   ui = WhitsClient(botnick)
   ui.run(server)

def shell(): 
   global ui
   Shell = type('Shell', (object,), {
      'notify': lambda self, *args: sys.stdout.write(' '.join(args) + '\n')
   })
   ui = Shell()
   process(sys.argv[1])

def exit(*args): 
   for arg in args: 
      if isinstance(arg, int): sys.exit(arg)
      elif hasattr(arg, '__call__'): arg()
      else: print(arg)
   sys.exit()

def main(argv=None): 
   argv = sys.argv if (argv is None) else argv
   try: opts, args = getopt.getopt(argv[1:], 'i', ['irc'])
   except getopt.GetoptError as err: 
      exit(err, 2)
   else: flags = {flag for (flag, value) in opts} or {}

   # whits.py -i | whits.py --irc
   if (flags == {'-i'}) or (flags == {'--irc'}) and (not args): 
      irc()

   # whits.py 'Command line input.'
   elif (flags == {}) and (len(args) == 1): 
      shell()

   else: exit('Error: Unknown command\n', 2)

if __name__ == '__main__': 
   main()