from django.views import generic


class SearchableListView(generic.ListView):
    model = None
    template_name = None
    search_form_class = None
    override_fields = {}
    queryset_distinct = None
    order_by = None

    def get_search_form(self):
        return self.search_form_class() if self.search_form_class else None

    def initialize_form(self):
        form = self.get_search_form()
        fields = self.get_search_fields()
        search_query = self.request.GET

        if search_query:
            for field in fields:
                if field in search_query and len(search_query[field]) > 0:
                    form.fields[field].initial = search_query[field]
        return form

    def get_search_fields(self):
        try:
            form = self.get_search_form()
            searchable_fields = [name for name, fields in form.fields.items()]
        except:
            searchable_fields = []
        return searchable_fields

    def filter_queryset(self):
        fields = self.get_search_fields()
        filters = {}
        form = self.get_search_form()

        for field in fields:
            if field in self.request.GET and len(self.request.GET[field]) > 0:
                if field in self.override_fields:
                    if type(self.override_fields[field]) == list:
                        for item in self.override_fields[field]:
                            filters[item] = form.fields[field].clean(
                                self.request.GET.get(field))
                    else:
                        overrided_field = self.override_fields[field]
                        try:
                            data = form.fields[field].clean(
                                self.request.GET.get(field))
                        except:
                            data = self.request.GET.get(field)
                        filters[overrided_field] = data
                else:
                    filters[field] = form.fields[field].clean(
                        self.request.GET.get(field))

        return filters

    def get_queryset(self):
        filters = self.filter_queryset()
        queryset = super(SearchableListView, self).get_queryset()
        if filters:
            queryset = queryset.filter(**filters)
        if self.order_by:
            queryset = queryset.order_by(*self.order_by)
        if self.queryset_distinct:
            queryset = queryset.distinct()
        return queryset

    def get_context_data(self, **kwargs):
        context = super(SearchableListView, self).get_context_data(**kwargs)
        context['search_form'] = self.initialize_form()
        return context