Source code for plata.shop.templatetags.plata_tags

from __future__ import absolute_import, unicode_literals

from django import forms, template
from django.db.models import ObjectDoesNotExist
from django.template.loader import render_to_string

# import plata
import plata.context_processors


register = template.Library()


@register.simple_tag(takes_context=True)
def load_plata_context(context):
    """
    Conditionally run plata's context processor using {% load_plata_context %}

    Rather than having the overheads involved in globally adding it to
    TEMPLATE_CONTEXT_PROCESSORS.
    """
    if "plata" not in context:
        context.update(plata.context_processors.plata_context(context["request"]))
    return ""


@register.filter
def quantity_ordered(product, order):
    """
    e.g. {% if product|quantity_ordered:plata.order > 0 %} ... {% endif %}
    """
    try:
        return order.items.values("quantity").get(product=product)["quantity"]
    except ObjectDoesNotExist:
        return 0


def _type_class(item):
    if isinstance(item.field.widget, forms.CheckboxInput):
        return "checkbox"
    elif isinstance(item.field.widget, forms.DateInput):
        return "date"
    elif isinstance(
        item.field.widget, (forms.RadioSelect, forms.CheckboxSelectMultiple)
    ):
        return "list"
    return ""


@register.simple_tag
def form_items(form):
    """
    Render all form items::

        {% form_items form %}
    """
    return "".join(
        render_to_string(
            "_form_item.html",
            {
                "item": field,
                "is_checkbox": isinstance(field.field.widget, forms.CheckboxInput),
                "type_class": _type_class(field),
            },
        )
        for field in form
    )


@register.inclusion_tag("_form_item.html")
def form_item(item, additional_classes=None):
    """
    Helper for easy displaying of form items::

        {% for field in form %}{% form_item field %}{% endfor %}
    """

    return {
        "item": item,
        "additional_classes": additional_classes,
        "is_checkbox": isinstance(item.field.widget, forms.CheckboxInput),
        "type_class": _type_class(item),
    }


@register.inclusion_tag("_form_item_plain.html")
def form_item_plain(item, additional_classes=None):
    """
    Helper for easy displaying of form items without any additional
    tags (table cells or paragraphs) or labels::

        {% form_item_plain field %}
    """

    return {
        "item": item,
        "additional_classes": additional_classes,
        "is_checkbox": isinstance(item.field.widget, forms.CheckboxInput),
        "type_class": _type_class(item),
    }


@register.tag
def form_errors(parser, token):
    """
    Show all form and formset errors::

        {% form_errors form formset1 formset2 %}

    Silently ignores non-existant variables.
    """

    tokens = token.split_contents()

    return FormErrorsNode(*tokens[1:])


class FormErrorsNode(template.Node):
    def __init__(self, *items):
        self.items = [template.Variable(item) for item in items]

    def render(self, context):
        items = []
        for item in self.items:
            try:
                var = item.resolve(context)
                if isinstance(var, dict):
                    items.extend(var.values())
                elif isinstance(var, (list, tuple)):
                    items.extend(var)
                else:
                    items.append(var)
            except template.VariableDoesNotExist:
                # We do not care too much
                pass

        errors = False

        form_list = []
        formset_list = []

        for i in items:
            if isinstance(i, forms.BaseForm):
                form_list.append(i)
            else:
                formset_list.append(i)

            if (
                getattr(i, "errors", None)
                or getattr(i, "non_field_errors", lambda: None)()
            ):
                errors = True

        if not errors:
            return ""

        return render_to_string(
            "_form_errors.html",
            {"forms": form_list, "formsets": formset_list, "errors": True},
        )