from django import newforms as forms
from django.newforms.util import flatatt, StrAndUnicode, smart_unicode
from itertools import chain

__all__ = ('VolSelect')

class RadioInput(StrAndUnicode):
    "An object used by RadioFieldRenderer that represents a single <input type='radio'>."
    def __init__(self, name, value, attrs, choice, index):
        self.name, self.value = name, value
        self.attrs = attrs
        self.choice_value = smart_unicode(choice[0])
        self.choice_label = smart_unicode(choice[1])
        self.index = index

    def __unicode__(self):
        return u'<label>%s %s</label>' % (self.tag(), self.choice_label)

    def is_checked(self):
        return self.value == self.choice_value

    def tag(self):
        if self.attrs.has_key('id'):
            self.attrs['id'] = '%s_%s' % (self.attrs['id'], self.index)
        final_attrs = dict(self.attrs, type='radio', name=self.name, value=self.choice_value)
        if self.is_checked():
            final_attrs['checked'] = 'checked'
        return u'<input%s />' % flatatt(final_attrs)

class RadioFieldRenderer(StrAndUnicode):
    "An object used by RadioSelect to enable customization of radio widgets."
    def __init__(self, name, value, attrs, choices):
        self.name, self.value, self.attrs = name, value, attrs
        self.choices = choices

    def __iter__(self):
        for i, choice in enumerate(self.choices):
            yield RadioInput(self.name, self.value, self.attrs.copy(), choice, i)

    def __getitem__(self, idx):
        choice = self.choices[idx] # Let the IndexError propogate
        return RadioInput(self.name, self.value, self.attrs.copy(), choice, idx)

    def __unicode__(self):
        "Outputs a <ul> for this set of radio fields."
        return u'<ul>\n%s\n</ul>' % u'\n'.join([u'<li>%s</li>' % w for w in self])

class VolInput(RadioInput):
    "An object used by RadioFieldRenderer that represents a single <input type='radio'>."
    def __unicode__(self):
        return u'<td class="input">%s</td>' % self.tag()

class VolFieldRenderer(RadioFieldRenderer):
	def __iter__(self):
		for i, choice in enumerate(self.choices):
			yield VolInput(self.name, self.value, self.attrs.copy(), choice, i)
	def __getitem__(self, idx):
		choice = self.choices[idx] # Let the IndexError propogate
		return VolInput(self.name, self.value, self.attrs.copy(), choice, idx)
	def __unicode__(self):
		"Outputs the set of radio fields."
		return u'\n'.join([u'%s' % w for w in self])


class VolSelect(forms.RadioSelect):
	def render(self, name, value, attrs=None, choices=()):
		"Returns a VolFieldRenderer instance rather than a Unicode string."
		if value is None: value = ''
		str_value = smart_unicode(value)
		attrs = attrs or {}
		return VolFieldRenderer(name, str_value, attrs, list(chain(self.choices, choices)))