Pagination does not work after Ajax call in Rails

I am using plugin Kaminari for pagination. I am Ajaxifing my application and I encountered a problem. I have a form with paginated data plus form for filtering data (both via Ajax). At start pagination works good, and the url's for particular pages are '/admin/rooms?page=X'. After ajax filtering those url's change for '/admin/rooms/filter?page=X'. I can specify the action to trigger when paginating by:

<%= paginate @rooms, :params => {:controller => 'rooms', :action => 'index'}, :remote => true %>

but then variable @rooms gets resetted in index and I paginate unfiltered data again.

Any ideas how could I fix it?

Here's some code

rooms_controller.rb:

class Admin::RoomsController < AdminController
def index
        @rooms = Room.all
        @rooms = Kaminari.paginate_array(@rooms).page(params[:page]).per(5)
        @filter_values = [['Room number', 'room_number'], ['Person count', 'person_count'], ['Room class', 'room_class']]
end

def filter
        case params[:filter_by]
        when 'room_number'
                @rooms = Room.find(:all, :conditions => ["CAST(room_number AS VARCHAR) LIKE ?", "#{params[:filter_value]}%"])
        when 'person_count'
                @rooms = Room.find(:all, :conditions => ["person_count LIKE ?", "#{params[:filter_value]}%"])
        else
                @rooms = Room.joins(:room_class).where("lower(class_name) LIKE '#{params[:filter_value]}%'")
        end

        @rooms = Kaminari.paginate_array(@rooms).page(params[:page]).per(5)
        respond_to do |format|
                format.html { redirect_to admin_rooms_path }
                format.js
        end
end

index.html.erb:

<%= label_tag 'Filter:  ' %>
<%= form_tag(filter_admin_rooms_path, :remote => true) do %>
        <%= select_tag :filter_by, options_for_select(@filter_values) %>
        <%= text_field_tag :filter_value %>
        <%= submit_tag 'Filter', :disable_with => 'Filtering..' %>
<% end %>

...

<div id="rooms_list">
        <%= render 'admin/rooms/shared/rooms_list' %>
</div>

_rooms_list.html.erb:

<div id="paginator">
        <%= paginate @rooms, :remote => true %>
</div>
<table class="table_listing" style="width: 60%">
        ...
</table>

Solution

Problem solved by passing parameters again to index and forcing paginate to route to 'rooms#index', not the current page (not visible cause of Ajax though).

_rooms_list.html.erb:

<%= paginate @rooms, :params => {:controller => 'rooms', :action => 'index'}, :remote => true %>

Parametrs are passed to index by GET from the present params variable.

rooms_controller.rb:

def index
        if params[:filter_value].nil?
                @rooms = Room.all
        else
                @rooms = test_filter(params[:filter_value])
        end

        @rooms = Kaminari.paginate_array(@rooms).page(params[:page]).per(5)
        @errors = flash[:errors] || []
        @filter_values = [['Room number', 'room_number'], ['Person count', 'person_count'], ['Room class', 'room_class']]
end

def filter
        case params[:filter_by]
        when 'room_number'
                @rooms = Room.find(:all, :conditions => ["CAST(room_number AS VARCHAR) LIKE ?", "#{params[:filter_value]}%"])
        when 'person_count'
                @rooms = Room.find(:all, :conditions => ["person_count LIKE ?", "#{params[:filter_value]}%"])
        else
                @rooms = Room.joins(:room_class).where("lower(class_name) LIKE '#{params[:filter_value]}%'")
        end

        @rooms = Kaminari.paginate_array(@rooms).page(params[:page]).per(5)
        params[:authenticity_token] = nil
        params[:commit] = nil

        respond_to do |format|
                format.html { redirect_to admin_rooms_path }
                format.js
        end
end

def test_filter(val)
        rooms = Room.find(:all, :conditions => ["CAST(room_number AS VARCHAR) LIKE ?", "#{val}%"])
        rooms
end

test_filter is to remove/rename of course. I nil some parameter that I think shouldn't be passed in params to the next page when paginate.