Add cart of product

app/assets/javascripts/carts.js.coffee

+# Place all the behaviors and hooks related to the matching controller here.
+# All this logic will automatically be available in application.js.
+# You can use CoffeeScript in this file: http://coffeescript.org/

app/assets/javascripts/line_items.js.coffee

+# Place all the behaviors and hooks related to the matching controller here.
+# All this logic will automatically be available in application.js.
+# You can use CoffeeScript in this file: http://coffeescript.org/

app/assets/stylesheets/carts.css.scss

+// Place all the styles related to the carts controller here.
+// They will automatically be included in application.css.
+// You can use Sass (SCSS) here: http://sass-lang.com/

app/assets/stylesheets/custom.css.scss

@@ -84,4 +84,8 @@ h2 {
 
 
 .col-sm-3 {
 .col-sm-3 {
   width: 20%;
   width: 20%;
+}
+
+.button_to .btn-default {
+  background-color: #FFC741;
 }
 }
\ No newline at end of file

app/assets/stylesheets/line_items.css.scss

+// Place all the styles related to the line_items controller here.
+// They will automatically be included in application.css.
+// You can use Sass (SCSS) here: http://sass-lang.com/

app/controllers/application_controller.rb

@@ -5,9 +5,25 @@ class ApplicationController < ActionController::Base
 
 
   rescue_from ActiveRecord::RecordNotFound, :with => :record_not_found
   rescue_from ActiveRecord::RecordNotFound, :with => :record_not_found
 
 
+  def current_cart
+    Cart.find(session[:cart_id])
+  rescue ActiveRecord::RecordNotFound
+    cart = Cart.create
+    session[:cart_id] = cart.id
+    cart
+  end
+
   private
   private
 
 
-  def record_not_found
-    redirect_to root_path
+    def record_not_found
+      redirect_to root_path
+    end
+
+    def current_cart
+      Cart.find(session[:cart_id])
+    rescue ActiveRecord::RecordNotFound
+      cart = Cart.create
+      session[:cart_id] = cart.id
+      cart
   end
   end
 end
 end

app/controllers/carts_controller.rb

+class CartsController < ApplicationController
+  before_action :set_cart, only: [:show, :edit, :update, :destroy]
+
+  def index
+    @carts = Cart.all
+  end
+
+  def show
+  end
+
+  def new
+    @cart = Cart.new
+  end
+
+  def edit
+  end
+
+  def create
+    @cart = Cart.new(cart_params)
+
+    respond_to do |format|
+      if @cart.save
+        format.html { redirect_to @cart, notice: 'Cart was successfully created.' }
+        format.json { render :show, status: :created, location: @cart }
+      else
+        format.html { render :new }
+        format.json { render json: @cart.errors, status: :unprocessable_entity }
+      end
+    end
+  end
+
+  def update
+    respond_to do |format|
+      if @cart.update(cart_params)
+        format.html { redirect_to @cart, notice: 'Cart was successfully updated.' }
+        format.json { render :show, status: :ok, location: @cart }
+      else
+        format.html { render :edit }
+        format.json { render json: @cart.errors, status: :unprocessable_entity }
+      end
+    end
+  end
+
+  def destroy
+    @cart.destroy
+    respond_to do |format|
+      format.html { redirect_to carts_url, notice: 'Cart was successfully destroyed.' }
+      format.json { head :no_content }
+    end
+  end
+
+  private
+
+    def set_cart
+      @cart = Cart.find(params[:id])
+    end
+
+    def cart_params
+      params[:cart]
+    end
+end

app/controllers/line_items_controller.rb

+class LineItemsController < ApplicationController
+  before_action :set_line_item, only: [:show, :edit, :update, :destroy]
+
+  def index
+    @line_items = LineItem.all
+  end
+
+  def show
+  end
+
+  def new
+    @line_item = LineItem.new
+  end
+
+  def edit
+  end
+
+  def create
+    @cart = current_cart
+    product = Product.find(params[:product_id])
+    @line_item = @cart.add_product(product.id)
+
+    redirect_to @line_item.cart if @line_item.save
+  end
+
+  def update
+    respond_to do |format|
+      if @line_item.update(line_item_params)
+        format.html { redirect_to @line_item, notice: 'Line item was successfully updated.' }
+        format.json { render :show, status: :ok, location: @line_item }
+      else
+        format.html { render :edit }
+        format.json { render json: @line_item.errors, status: :unprocessable_entity }
+      end
+    end
+  end
+
+  def destroy
+    @line_item.destroy
+    respond_to do |format|
+      format.html { redirect_to line_items_url, notice: 'Line item was successfully destroyed.' }
+      format.json { head :no_content }
+    end
+  end
+
+  private
+    def set_line_item
+      @line_item = LineItem.find(params[:id])
+    end
+
+    def line_item_params
+      params.require(:line_item).permit(:product_id, :cart_id)
+    end
+end

app/helpers/carts_helper.rb

+module CartsHelper
+end

app/helpers/line_items_helper.rb

+module LineItemsHelper
+end

app/models/cart.rb

+class Cart < ActiveRecord::Base
+  has_many :line_items, :dependent => :destroy
+
+  def add_product(product_id)
+    current_item = line_items.where(product_id: product_id).first
+    if current_item
+      current_item.quantity += 1
+    else
+      current_item = LineItem.new(product_id: product_id)
+      line_items << current_item
+    end
+    current_item
+  end
+end

app/models/line_item.rb

+class LineItem < ActiveRecord::Base
+  belongs_to :product
+  belongs_to :cart
+end

app/models/product.rb

 class Product < ActiveRecord::Base
 class Product < ActiveRecord::Base
 
 
+  scope :newest, -> { order(created_at: :desc).limit(5) }
+
   belongs_to :category
   belongs_to :category
+  has_many :line_items
 
 
   validates :name, presence: true, length: { maximum: 200 }
   validates :name, presence: true, length: { maximum: 200 }
   validates :price, presence: true, numericality: true,
   validates :price, presence: true, numericality: true,
@@ -8,12 +11,21 @@ class Product < ActiveRecord::Base
   validates :description, presence: true
   validates :description, presence: true
   validate  :photo_size
   validate  :photo_size
 
 
-  scope :newest, -> { order(created_at: :desc).limit(5) }
+  before_destroy :ensure_not_referenced_by_any_line_item
 
 
   mount_uploader :photo, ImageUploader
   mount_uploader :photo, ImageUploader
 
 
   paginates_per 10
   paginates_per 10
 
 
+  def ensure_not_referenced_by_any_line_item
+    if line_items.count.zero?
+      return true
+    else
+      errors[:base] << 'Line Items present'
+      return false
+    end
+  end
+  
   private
   private
 
 
     def photo_size
     def photo_size

app/views/carts/_form.html.erb

+<%= form_for(@cart) do |f| %>
+  <% if @cart.errors.any? %>
+    <div id="error_explanation">
+      <h2><%= pluralize(@cart.errors.count, "error") %> prohibited this cart from being saved:</h2>
+
+      <ul>
+      <% @cart.errors.full_messages.each do |message| %>
+        <li><%= message %></li>
+      <% end %>
+      </ul>
+    </div>
+  <% end %>
+
+  <div class="actions">
+    <%= f.submit %>
+  </div>
+<% end %>

app/views/carts/edit.html.erb

+<h1>Editing Cart</h1>
+
+<%= render 'form' %>
+
+<%= link_to 'Show', @cart %> |
+<%= link_to 'Back', carts_path %>

app/views/carts/index.html.erb

+<p id="notice"><%= notice %></p>
+
+<h1>Listing Carts</h1>
+
+<table>
+  <thead>
+    <tr>
+      <th colspan="3"></th>
+    </tr>
+  </thead>
+
+  <tbody>
+    <% @carts.each do |cart| %>
+      <tr>
+        <td><%= link_to 'Show', cart %></td>
+        <td><%= link_to 'Edit', edit_cart_path(cart) %></td>
+        <td><%= link_to 'Destroy', cart, method: :delete, data: { confirm: 'Are you sure?' } %></td>
+      </tr>
+    <% end %>
+  </tbody>
+</table>
+
+<br>
+
+<%= link_to 'New Cart', new_cart_path %>

app/views/carts/index.json.jbuilder

+json.array!(@carts) do |cart|
+  json.extract! cart, :id
+  json.url cart_url(cart, format: :json)
+end

app/views/carts/new.html.erb

+<h1>New Cart</h1>
+
+<%= render 'form' %>
+
+<%= link_to 'Back', carts_path %>

app/views/carts/show.html.erb

+<%= provide(:title, 'Current Cart') %>
+<h1 class='page-header'>Venshop Cart Infomation</h1>
+<ul>
+  <% @cart.line_items.each do |item| %>
+    <li><%= item.quantity %> &times; <%= item.product.name %></li>
+  <% end %>
+</ul>

app/views/carts/show.json.jbuilder

+json.extract! @cart, :id, :created_at, :updated_at

app/views/line_items/_form.html.erb

+<%= form_for(@line_item) do |f| %>
+  <% if @line_item.errors.any? %>
+    <div id="error_explanation">
+      <h2><%= pluralize(@line_item.errors.count, "error") %> prohibited this line_item from being saved:</h2>
+
+      <ul>
+      <% @line_item.errors.full_messages.each do |message| %>
+        <li><%= message %></li>
+      <% end %>
+      </ul>
+    </div>
+  <% end %>
+
+  <div class="field">
+    <%= f.label :product_id %><br>
+    <%= f.number_field :product_id %>
+  </div>
+  <div class="field">
+    <%= f.label :cart_id %><br>
+    <%= f.number_field :cart_id %>
+  </div>
+  <div class="actions">
+    <%= f.submit %>
+  </div>
+<% end %>

app/views/line_items/edit.html.erb

+<h1>Editing Line Item</h1>
+
+<%= render 'form' %>
+
+<%= link_to 'Show', @line_item %> |
+<%= link_to 'Back', line_items_path %>

app/views/line_items/index.html.erb

+<p id="notice"><%= notice %></p>
+
+<h1>Listing Line Items</h1>
+
+<table>
+  <thead>
+    <tr>
+      <th>Product</th>
+      <th>Cart</th>
+      <th colspan="3"></th>
+    </tr>
+  </thead>
+
+  <tbody>
+    <% @line_items.each do |line_item| %>
+      <tr>
+        <td><%= line_item.product_id %></td>
+        <td><%= line_item.cart_id %></td>
+        <td><%= link_to 'Show', line_item %></td>
+        <td><%= link_to 'Edit', edit_line_item_path(line_item) %></td>
+        <td><%= link_to 'Destroy', line_item, method: :delete, data: { confirm: 'Are you sure?' } %></td>
+      </tr>
+    <% end %>
+  </tbody>
+</table>
+
+<br>
+
+<%= link_to 'New Line item', new_line_item_path %>

app/views/line_items/index.json.jbuilder

+json.array!(@line_items) do |line_item|
+  json.extract! line_item, :id, :product_id, :cart_id
+  json.url line_item_url(line_item, format: :json)
+end

app/views/line_items/new.html.erb

+<h1>New Line Item</h1>
+
+<%= render 'form' %>
+
+<%= link_to 'Back', line_items_path %>

app/views/line_items/show.html.erb

+<p id="notice"><%= notice %></p>
+
+<p>
+  <strong>Product:</strong>
+  <%= @line_item.product_id %>
+</p>
+
+<p>
+  <strong>Cart:</strong>
+  <%= @line_item.cart_id %>
+</p>
+
+<%= link_to 'Edit', edit_line_item_path(@line_item) %> |
+<%= link_to 'Back', line_items_path %>

app/views/line_items/show.json.jbuilder

+json.extract! @line_item, :id, :product_id, :cart_id, :created_at, :updated_at

app/views/products/_product.html.erb

@@ -4,4 +4,5 @@
   </div>
   </div>
   <h4><%= link_to product.name, product_path(product) %></h4>
   <h4><%= link_to product.name, product_path(product) %></h4>
   <span class='price-col'>$<%= product.price %></span>
   <span class='price-col'>$<%= product.price %></span>
+  <%= button_to 'Add to Cart', line_items_path(product_id: product), { class: 'btn btn-default' } %>
 </div>
 </div>
\ No newline at end of file

app/views/products/show.html.erb

@@ -17,6 +17,6 @@
     <p><%= @product.description %></p>
     <p><%= @product.description %></p>
   </div>
   </div>
   <div class='row'>
   <div class='row'>
-    <%= link_to 'Buy', '#', class: 'btn btn-primary' %>
+    <%= button_to 'Buy', line_items_path(product_id: @product), { class: 'btn btn-default' } %>
   </div>
   </div>
 <% end %>
 <% end %>
\ No newline at end of file

config/routes.rb

 Rails.application.routes.draw do
 Rails.application.routes.draw do
+  resources :line_items
+
+  resources :carts
+
   namespace :admin do
   namespace :admin do
     resources :products
     resources :products
   end
   end

db/migrate/20141112063407_create_carts.rb

+class CreateCarts < ActiveRecord::Migration
+  def change
+    create_table :carts do |t|
+
+      t.timestamps null: false
+    end
+  end
+end

db/migrate/20141112064743_create_line_items.rb

+class CreateLineItems < ActiveRecord::Migration
+  def change
+    create_table :line_items do |t|
+      t.integer :product_id
+      t.integer :cart_id
+
+      t.timestamps null: false
+    end
+  end
+end

db/migrate/20141112100303_add_quantity_to_line_item.rb

+class AddQuantityToLineItem < ActiveRecord::Migration
+  def change
+    add_column :line_items, :quantity, :integer, :default => 1
+  end
+end

db/migrate/20141112101735_combine_items_in_cart.rb

+class CombineItemsInCart < ActiveRecord::Migration
+  def change
+    Cart.all.each do |cart|
+      sums = cart.line_items.group(:product_id).sum(:quantity)
+
+      sums.each do |product_id, quantity|
+        if quantity > 1
+          cart.line_items.where(product_id: product_id).delete_all
+          cart.line_items.create(product_id: product_id, quantity: quantity)
+        end
+      end
+    end
+  end
+end

db/schema.rb

@@ -11,7 +11,12 @@
 #
 #
 # It's strongly recommended that you check this file into your version control system.
 # It's strongly recommended that you check this file into your version control system.
 
 
-ActiveRecord::Schema.define(version: 20141111033549) do
+ActiveRecord::Schema.define(version: 20141112101735) do
+
+  create_table "carts", force: true do |t|
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+  end
 
 
   create_table "categories", force: true do |t|
   create_table "categories", force: true do |t|
     t.string   "name",       limit: 255
     t.string   "name",       limit: 255
@@ -19,6 +24,14 @@ ActiveRecord::Schema.define(version: 20141111033549) do
     t.datetime "updated_at"
     t.datetime "updated_at"
   end
   end
 
 
+  create_table "line_items", force: true do |t|
+    t.integer  "product_id", limit: 4
+    t.integer  "cart_id",    limit: 4
+    t.datetime "created_at",                       null: false
+    t.datetime "updated_at",                       null: false
+    t.integer  "quantity",   limit: 4, default: 1
+  end
+
   create_table "products", force: true do |t|
   create_table "products", force: true do |t|
     t.string   "name",        limit: 255
     t.string   "name",        limit: 255
     t.decimal  "price",                     precision: 10, scale: 2
     t.decimal  "price",                     precision: 10, scale: 2

test/controllers/carts_controller_test.rb

+require 'test_helper'
+
+class CartsControllerTest < ActionController::TestCase
+  setup do
+    @cart = carts(:one)
+  end
+
+  test "should get index" do
+    get :index
+    assert_response :success
+    assert_not_nil assigns(:carts)
+  end
+
+  test "should get new" do
+    get :new
+    assert_response :success
+  end
+
+  test "should create cart" do
+    assert_difference('Cart.count') do
+      post :create, cart: {  }
+    end
+
+    assert_redirected_to cart_path(assigns(:cart))
+  end
+
+  test "should show cart" do
+    get :show, id: @cart
+    assert_response :success
+  end
+
+  test "should get edit" do
+    get :edit, id: @cart
+    assert_response :success
+  end
+
+  test "should update cart" do
+    patch :update, id: @cart, cart: {  }
+    assert_redirected_to cart_path(assigns(:cart))
+  end
+
+  test "should destroy cart" do
+    assert_difference('Cart.count', -1) do
+      delete :destroy, id: @cart
+    end
+
+    assert_redirected_to carts_path
+  end
+end

test/controllers/line_items_controller_test.rb

+require 'test_helper'
+
+class LineItemsControllerTest < ActionController::TestCase
+  setup do
+    @line_item = line_items(:one)
+  end
+
+  test "should get index" do
+    get :index
+    assert_response :success
+    assert_not_nil assigns(:line_items)
+  end
+
+  test "should get new" do
+    get :new
+    assert_response :success
+  end
+
+  test "should create line_item" do
+    assert_difference('LineItem.count') do
+      post :create, line_item: { cart_id: @line_item.cart_id, product_id: @line_item.product_id }
+    end
+
+    assert_redirected_to line_item_path(assigns(:line_item))
+  end
+
+  test "should show line_item" do
+    get :show, id: @line_item
+    assert_response :success
+  end
+
+  test "should get edit" do
+    get :edit, id: @line_item
+    assert_response :success
+  end
+
+  test "should update line_item" do
+    patch :update, id: @line_item, line_item: { cart_id: @line_item.cart_id, product_id: @line_item.product_id }
+    assert_redirected_to line_item_path(assigns(:line_item))
+  end
+
+  test "should destroy line_item" do
+    assert_difference('LineItem.count', -1) do
+      delete :destroy, id: @line_item
+    end
+
+    assert_redirected_to line_items_path
+  end
+end

test/fixtures/carts.yml

+# Read about fixtures at http://api.rubyonrails.org/classes/ActiveRecord/FixtureSet.html
+
+# This model initially had no columns defined.  If you add columns to the
+# model remove the '{}' from the fixture names and add the columns immediately
+# below each fixture, per the syntax in the comments below
+#
+one: {}
+# column: value
+#
+two: {}
+#  column: value

test/fixtures/line_items.yml

+# Read about fixtures at http://api.rubyonrails.org/classes/ActiveRecord/FixtureSet.html
+
+one:
+  product_id: 1
+  cart_id: 1
+
+two:
+  product_id: 1
+  cart_id: 1

test/models/cart_test.rb

+require 'test_helper'
+
+class CartTest < ActiveSupport::TestCase
+  # test "the truth" do
+  #   assert true
+  # end
+end

test/models/line_item_test.rb

+require 'test_helper'
+
+class LineItemTest < ActiveSupport::TestCase
+  # test "the truth" do
+  #   assert true
+  # end
+end