How to pass an ajax date to jquery? - ruby-on-rails

Question

I have a datepicker, and I want to use the picked date in a query in a Movements table, to retrieve corresponding turnover. But "currentDate" does not load with the picked date : I have a "invalid date" exception caught. How should I do it ?
$("#datepicker").change(function(){
var currentDate = $( "#datepicker" ).datepicker( "getDate" );
var wantedTO = <%=Movement.where(:movementDate =>Date.parse("currentDate")).sum("turnover")%>;
$(document).ajaxComplete(function(){ $("#result").html("<p>Result here : </p>" + wantedTO);
});
});
Note that if I replace
var wantedTO = <%=Movement.where(:movementDate =>Date.parse("currentDate")).sum("turnover")%>;
by
var wantedTO = <%=Movement.where(:movementDate =>Date.today).sum("turnover")%>;
it's giving me today's turnover. So I might not be so far !
EDIT :
To be sure of the date format, I added a line
var dateString = $.datepicker.formatDate("yy-mm-dd", currentDate);
And checked OK that if I put a manual date in that format then, it's working. It seems that it's a problem of how to pass this variable, but I can't fix it. Any idea ?

Answer 1

OK I have my answer. In case other newbies would face the same problem, I will summarize it. There was a big mistake in my code : you can't do a ruby query inside the Ajax code. So waht, you have to do :
1- Create a new method (sort) in your controller (movements_controller.rb) :
def sort
selected_date = params[:date]
new_html_to_return = Movement.where(:movementDate =>Date.parse(params[:date])).sum("turnover")
render :text => new_html_to_return
end
2- Create a POST ajax function in your view (index.html.erb) :
<script>
$(document).ready(function(){
var $datepicker = $("#datepicker"),
currentDate = new Date(),
dateString = "";
$datepicker.change(function(){
currentDate = $datepicker.datepicker( "getDate" );
dateString = $.datepicker.formatDate("yy-mm-dd", currentDate);
$.ajax({
type: "POST",
// You're sending the variable to your Ruby on Rails controller
url: "movements/sort/",
data: {"date":dateString},
}).done(function(data) {
$("#result").html("<p>Turnover: </p>" + data)
});
});
});
</script>
3- Create the associated route in your routes.rb :
post "movements/sort"
And you're done ! Enjoy !