text: """Wiki main program.  Imported and run by cgi3.py."""
  
  import os, re, cgi, sys, tempfile
  escape = cgi.escape
  
  def main():
      form = cgi.FieldStorage()
      print "Content-type: text/html"
      print
      cmd = form.getvalue("cmd", "view")
      page = form.getvalue("page", "FrontPage")
      wiki = WikiPage(page)
      method = getattr(wiki, 'cmd_' + cmd, None) or wiki.cmd_view
      method(form)
  
  class WikiPage:
  
      homedir = tempfile.gettempdir()
      scripturl = os.path.basename(sys.argv[0])
  
      def __init__(self, name):
          if not self.iswikiword(name):
              raise ValueError, "page name is not a wiki word"
          self.name = name
          self.load()
  
      def cmd_view(self, form):
          print "<h1>", escape(self.splitwikiword(self.name)), "</h1>"
          print "<p>"
          for line in self.data.splitlines():
              line = line.rstrip()
              if not line:
                  print "<p>"
              else:
                  print self.formatline(line)
          print "<hr>"
          print "<p>", self.mklink("edit", self.name, "Edit this page") + ";"
          print self.mklink("view", "FrontPage", "go to front page") + "."
  
      def formatline(self, line):
          words = []
          for word in re.split('(\W+)', line):
              if self.iswikiword(word):
                  if os.path.isfile(self.mkfile(word)):
                      word = self.mklink("view", word, word)
                  else:
                      word = self.mklink("new", word, word + "*")
              else:
                  word = escape(word)
              words.append(word)
          return "".join(words)
  
      def cmd_edit(self, form, label="Change"):
          print "<h1>", label, self.name, "</h1>"
          print '<form method="POST" action="%s">' % self.scripturl
          s = '<textarea cols="70" rows="20" name="text">%s</textarea>'
          print s % self.data
          print '<input type="hidden" name="cmd" value="create">'
          print '<input type="hidden" name="page" value="%s">' % self.name
          print '<br>'
          print '<input type="submit" value="%s Page">' % label
          print "</form>"
  
      def cmd_create(self, form):
          self.data = form.getvalue("text", "").strip()
          error = self.store()
          if error:
              print "<h1>I'm sorry.  That didn't work</h1>"
              print "<p>An error occurred while attempting to write the file:"
              print "<p>", escape(error)
          else:
              # Use a redirect directive, to avoid "reload page" problems
              print "<head>"
              s = '<meta http-equiv="refresh" content="1; URL=%s">'
              print s % (self.scripturl + "?cmd=view&page=" + self.name)
              print "<head>"
              print "<h1>OK</h1>"
              print "<p>If nothing happens, please click here:",
              print self.mklink("view", self.name, self.name)
  
      def cmd_new(self, form):
          self.cmd_edit(form, label="Create")
  
      def iswikiword(self, word):
          return re.match("[A-Z][a-z]+([A-Z][a-z]*)+", word)
  
      def splitwikiword(self, word):
          chars = []
          for c in word:
              if chars and c.isupper():
                  chars.append(' ')
              chars.append(c)
          return "".join(chars)
  
      def mkfile(self, name=None):
          if name is None:
              name = self.name
          return os.path.join(self.homedir, name + ".txt")
  
      def mklink(self, cmd, page, text):
          link = self.scripturl + "?cmd=" + cmd + "&page=" + page
          return '<a href="%s">%s</a>' % (link, text)
  
      def load(self):
          try:
              f = open(self.mkfile())
              data = f.read().strip()
              f.close()
          except IOError:
              data = ""
          self.data = data
  
      def store(self):
          data = self.data
          try:
              f = open(self.mkfile(), "w")
              f.write(data)
              if data and not data.endswith('\n'):
                  f.write('\n')
              f.close()
              return ""
          except IOError, err:
              return "IOError: %s" % str(err)
  