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Online Store Directions

1. Create a Rails OnlineStore project that implements a shopping cart with models Customer, CatalogItem, ShoppingCart, and LineItem. Use these fields for the models:
    
   
   Customer:   name:string   phone_number:string   address:string
    
   CatalogItem:   catid:string   title:string   price:float
    
   ShoppingCart:   customer_id:integer
    
   LineItem:   quantity:integer   shopping_cart_id:integer   catalog_item_id:integer
    
   
   Then make these modifications to the project:
    
   
   1. Set up these one-to-many relationships.
       
      
      Customer (one) → ShoppingCart (many)
       
      ShoppingCart (one) → LineItem (many)
       
      CatalogItem (one) → LineItem (many)
       
      Here is the code to set up the one-to-many relationships:
      

      In the Customer model:
         has_many :shopping_carts
      
      In the ShoppingCart model:
         belongs_to :customer
         has_many :line_items
         
      In the LineItem model:
         belongs_to :shopping_cart
         belongs_to :catalog_item
      
      In the Catalog model:
         has_many :line_items
      

      
      
   2. In the form for ShoppingCart, replace the textfields for the foreign keys in by dropdown menus that show the names of the possible customers:
      

      <!--
      Original code:
      <%= f.number_field :customer_id %>
      -->
      <% @c = Customer.all %>
      <% @options_cust = @c.collect do |c| %>
      <%    [c.name, c.id] %>
      <% end %>
      <%= f.select :customer_id, @options_cust %>
      

   3. On the LineItem form, show the catid, title, and price, with radio buttons to indicate the item to be ordered:
      

      <!--
      <%= f.number_field :catalog_item_id %>
      -->
      <% CatalogItem.all.each do |citem| %>
         <%= f.radio_button :catalog_item_id, citem.id %>
            <%=  citem.title + " " + citem.price.to_s %><br />
      <% end %>
      

   4. For the ShoppingCart index view, show the customer name instead of the customer id:
      

      Replace 
         @shopping_cart.customer_id 
      by
         @shopping_cart.customer.name
      

      In addition, show this information for each line item:
       
      
      catid   title   price   quantity   extended price (price * quantity)
      
      Also, show the total amount for items ordered (Sum of all the extended prices):
      

      Replace the table in the LineItem index view by this code:
      
      <table>
      <tr> 
         <th>Catalog ID</th>
         <th>Title</th>
         <th>Price</th>
         <th>Quantity</th>
         <th>Extended Price</th>
      </tr>
      <% @shopping_cart.line_items.each do |litem| %>
      <tr> 
         <td><%= litem.catalog_item.catid %></td>
         <td><%= litem.catalog_item.title %></td>
         <td><%= litem.catalog_item.price %></td>
         <td><%= litem.quantity %></td>
         <td><%= litem.catalog_item.price * litem.quantity %></td>
      </tr>
      <% end %>
      </table>
      

   5. On the Customer index view, place links to these index views at the bottom: CatalogItem, ShoppingCart, LineItem:
      

      <p><%= link_to "Shopping Cart Index", shopping_carts_path %></p>
      <p><%= link_to "Catalog Item Index", catalog_items_path %></p>
      <p><%= link_to "Line Item Index", line_items_path %></p>