#!/usr/bin/env python

import web
from pprint import pformat

template = """
<form name="main" method="post"> %s
<input type="submit"/>
</form>'
"""
urls = ('/', 'index')
app = web.application(urls, globals())


class CheckboxList(web.form.Input):
    """CheckboxList input."""

    def __init__(self, name, args, *validators, **attrs):
        self.args = args
        super(CheckboxList, self).__init__(name, *validators, **attrs)

    def render(self):
        attrs = self.attrs.copy()
        x = '<fieldset %s>\n' % attrs
        for arg in self.args:
            chk_attrs = web.form.AttributeList()
            if isinstance(arg, (tuple, list)):
                value, desc= arg
            else:
                value, desc = arg, arg
            chk_attrs["name"] = self.name
            chk_attrs["type"] = "checkbox"
            chk_attrs["value"] = value
            if isinstance(self.value, (tuple, list)) and value in self.value:
                chk_attrs["checked"] = "checked"

            x += ' <label><input %s/>  %s</label>\n' % (chk_attrs, web.net.websafe(desc))
        x += '</fieldset>\n'
        return x

myform = web.form.Form(CheckboxList(name='chk', args=[('a', 'aa'), ('b', 'bb'), ('c', 'cc')]))

class index:
      def GET(self):
          form = myform(dict(chk=['a','c']))
          return template % form.render()

      def POST(self):
          form = myform(web.input(chk=[]))
          return pformat(form.d)

if __name__=="__main__":
      web.internalerror = web.debugerror
      app.run()