Ggthjy

I've the following scenario: the user clicks the "Sales" button which redirects to the creation view of the Shopping Cart. Then, the user enters the EAN code and the Quantity, presses "Add" and the view sends an AJAX request to the add_item method of the SalesController. Then, the controller searches the data for the EAN given and a row is added to the table via JS. Also, an Item object is added to an Items array in the Session object. I decided to persist this data in the Session because I want to save all the objects (Sale and SaleItems) at the same time when the user presses "Save".

SalesController

class SalesController < ApplicationController

  def new

    @sale = Sale.new

    @sale.saleItems.build

    cart_item

  end



  def create

    @sale = Sale.new()

    if(@sale.grabar(session[:items]))

      session[:items] = []

      redirect_to new_sale_url

    end

  end







  def add_item



      @item = SaleItem.new

      @item_atributos = Material.price(params[:item][:gtin]).first

      @item.quantity = params[:item][:cantidad]

      @item.material_id = @item_atributos.id

      @item.unit_price = @item_atributos.unit_price

      @item.total = @item.quantity*@item_atributos.unit_price

      cart_item

      session[:items] << @item







      respond_to do |format|

        format.js #{render :json => @precio}

      end



  end



  private

    def sales_params

      params.require(:sale).permit(:total,saleItems_attributes:[:sale_id,:material_id,:unit_price,

        :quantity,:total])

    end





end

Sale model

    class Sale < ApplicationRecord

      has_many :saleItems

      accepts_nested_attributes_for :saleItems



      def total(array)

        @total = 0

        array.map { |item| item["total"]}.sum

      end



      def grabar (array)

        ActiveRecord::Base.transaction do

          @sale = Sale.create!(total: total(array))

          array.each do |item|

            item[:sale_id] = @sale.id

            SaleItem.create!(item)

          end

        end

      end

    end

new.html.erb

<h3><%= yield(:title_text) %></h3>



<table id="tabla" class="table table-bordered">

  <thead>

    <tr>

      <th scope="col">Producto</th>

      <th scope="col">Cantidad</th>

      <th scope="col">Precio unitario</th>

      <th scope="col">Subtotal</th>

      <th scope="col">Acciones</th>

    </tr>

  </thead>

  <tbody>

  </tbody>

</table>



<div style="position: fixed;left: 0;bottom: 0;width: 100%;text-align:center">

<%= form_tag(add_item_path(:gtin,:cantidad), method: 'get', remote: true) do %>

<div style="display-block:inline">

  <%= label_tag(:gtin, 'Código') %>

  <%= text_field_tag "item[gtin]" %>

  <%= text_field_tag "item[cantidad]" %>

  <%= submit_tag("Agregar", :class => "btn btn-primary") %>

  <%= link_to "Vender", sales_path, class:"btn btn-success", :method => :post %>

<% end %>

</div>

</div>

add_item.js.erb

$("#tabla tbody").append("<%= j render partial: 'saleItem', locals: {item: @item, atributos: @item_atributos} %>");



$("#tabla").on('click', '#borrar', function () {

  $(this).closest('tr').remove();

  });

_saleItem.html.erb

<tr>

  <th scope="row">

    <%= @item_atributos.description %>

  </th>

  <td><%= @item.quantity %></td>

  <td><%= @item_atributos.unit_price %></td>

    <td><%= @item.quantity * @item_atributos.unit_price%></td>

  <td>

    <button type="button" id="borrar" class="btn btn-danger">Borrar</button>

  </td>

</tr>

The code works well but my questions aims at code quality and design. I want a solution based on the OOP. Have I used the ROR tools well? Where should I improve my design? For example, I'm not using the strong parameters. The DB transaction was developed manually looping through Item objects. I feel that this solution doesn't use all the ROR features that makes coding easier!