''' Schemas (sub) package, for form rendering and validation '''

import colander
import deform

from deform.renderer import configure_zpt_renderer

from .helpers import (
    deferred_csrf_default,
    deferred_csrf_validator
    )


# Base Schema

class CSRFSchema(colander.Schema):
    ''' base class for schemas with csrf validation '''

    csrf_token = colander.SchemaNode(
        colander.String(),
        default=deferred_csrf_default,
        validator=deferred_csrf_validator,
        widget=deform.widget.HiddenWidget(),
        )

    @classmethod
    def as_form(cls, request, url=None, **kwargs):
        ''' returns the schema as a form

        :param pyramid.request.Request request: the current request
        :param str url:
            form action url,
            url is not set, the current context and view name will be used to
            constuct a url for the form
        :param kwargs:
            additional parameters for the form rendering.
        '''
        if url is None:
            url = request.resource_url(request.context, request.view_name)
        schema = cls().bind(request=request)
        form = deform.Form(schema, action=url, **kwargs)
        return form


def includeme(config):
    '''
    Initialize the form schemas

    Activate this setup using ``config.include('ordr.schemas')``.

    '''
    # Make Deform widgets aware of our widget template paths
    configure_zpt_renderer(['ordr:templates/deform'])