how to execute function after cocoon add the record? - ruby-on-rails

Question

I'm using the cocoon gem in my rails project, and I have two "link_to_add_association", but I need that depending on which link_to is pressed to do a certain function, link_to with id "link_1" adds the records to the beginning of the table and the other one adds the records at the end with other values, this is my partial form:
= form_for([#billing, #payment]) do |f|
- if #payment.errors.any?
= render partial: 'layouts/partials/errors/form_errors', locals: { errors: #payment.errors }
= f.hidden_field :billing_id, value: #billing.id
.row
.col-md-6
.form-group.row
.col-md-4
= f.label :payment, class: 'form-control-label'
.col-md-8
= f.text_field :payment, class: 'form-control text-right', 'data-currency-format--live': '', 'data-target': '#total-pay'
.col-md-6
.form-group.row
.col-md-4
= f.label :day, class: 'form-control-label'
.col-md-6
= f.text_field :day, class: 'form-control datepicker', 'data-startView': 'days', 'data-minyear': #billing.date_bill.year, 'data-minmonth': #billing.date_bill.month, 'data-minday': #billing.date_bill.day
.col-md-1
.links
= link_to_add_association 'add', f, :payment_details, partial: 'payment_detail_fields',:"data-association-insertion-node" => "tbody.details",:"data-association-insertion-method" => "prepend", class:"btn btn-success btn-xs", id: "link_1"
.col-md-1
.links
= link_to_add_association 'add', f, :payment_details, partial: 'payment_detail_discount_fields',:"data-association-insertion-node" => "tbody.details",:"data-association-insertion-method" => "append", class:"btn btn-success btn-xs", id: "link_2"
.col-md-12
#payment_details
%table.tabla_personalizada
%thead
%tr
%th value_paid
%th voucher
%th accion
%th value_paid
%th value_paid
%th voucher
%th accion
%tbody.details
= f.fields_for :payment_details do |payment_detail|
= render 'payment_detail_fields', f: payment_detail
%tr
%td
%td
%td
%td
%td
%td
%td
%tr.descuentos
%td Descuento
%td Descuento
%td
%td
%td
%td
%td
.row
.col-md-12
= f.label :comments, class: 'form-control-label'
= f.text_area :comments, class: 'form-control', rows: 6
%hr
.row
.col-md-8
.form-group.row
.col-md-8
= f.submit :class => 'btn btn-primary'
- content_for :javascript do
:javascript
$(document).ready(function() {
$("#link_1").on("cocoon:after-insert", function() {
alert("element of link_1");
} )
$("#link_2").on("cocoon:after-insert", function() {
alert("element of link_2");
} )
});
I tried this code but I can't find a way to make it work
$(document).ready(function() {
$("#link_1").on("cocoon:after-insert", function() {
alert("element of link_1");
} )
$("#link_2").on("cocoon:after-insert", function() {
alert("element of link_1");
} )
});