diff --git a/Gemfile b/Gemfile
index bde2f2e..d9ae7a3 100644
--- a/Gemfile
+++ b/Gemfile
@@ -43,7 +43,6 @@ group :development, :test do
   gem 'byebug'
 
   # Access an IRB console on exception pages or by using <%= console %> in views
-  gem 'web-console', '~> 2.0'
 
   # Spring speeds up development by keeping your application running in the background. Read more: https://github.com/rails/spring
   gem 'spring'
diff --git a/Gemfile.lock b/Gemfile.lock
index e1b93b6..ee6949f 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -36,59 +36,58 @@ GEM
       minitest (~> 5.1)
       thread_safe (~> 0.3, >= 0.3.4)
       tzinfo (~> 1.1)
-    arel (6.0.0)
-    bcrypt (3.1.10)
-    binding_of_caller (0.7.2)
-      debug_inspector (>= 0.0.1)
+    arel (6.0.3)
+    bcrypt (3.1.11)
     builder (3.2.2)
-    byebug (5.0.0)
-      columnize (= 0.9.0)
-    coffee-rails (4.1.0)
+    byebug (9.0.5)
+    coffee-rails (4.1.1)
       coffee-script (>= 2.2.0)
-      railties (>= 4.0.0, < 5.0)
+      railties (>= 4.0.0, < 5.1.x)
     coffee-script (2.4.1)
       coffee-script-source
       execjs
-    coffee-script-source (1.9.1.1)
-    columnize (0.9.0)
-    debug_inspector (0.0.2)
-    devise (3.5.1)
+    coffee-script-source (1.10.0)
+    concurrent-ruby (1.0.2)
+    devise (4.2.0)
       bcrypt (~> 3.0)
       orm_adapter (~> 0.1)
-      railties (>= 3.2.6, < 5)
+      railties (>= 4.1.0, < 5.1)
       responders
-      thread_safe (~> 0.1)
       warden (~> 1.2.3)
     diff-lcs (1.2.5)
     erubis (2.7.0)
-    execjs (2.5.2)
-    faker (1.4.3)
+    execjs (2.7.0)
+    faker (1.6.5)
       i18n (~> 0.5)
-    globalid (0.3.5)
+    globalid (0.3.6)
       activesupport (>= 4.1.0)
     i18n (0.7.0)
-    jbuilder (2.3.0)
-      activesupport (>= 3.0.0, < 5)
+    jbuilder (2.6.0)
+      activesupport (>= 3.0.0, < 5.1)
       multi_json (~> 1.2)
-    jquery-rails (4.0.4)
-      rails-dom-testing (~> 1.0)
+    jquery-rails (4.1.1)
+      rails-dom-testing (>= 1, < 3)
       railties (>= 4.2.0)
       thor (>= 0.14, < 2.0)
     json (1.8.3)
-    kaminari (0.16.3)
+    kaminari (0.17.0)
       actionpack (>= 3.0.0)
       activesupport (>= 3.0.0)
-    loofah (2.0.2)
+    loofah (2.0.3)
       nokogiri (>= 1.5.9)
-    mail (2.6.3)
-      mime-types (>= 1.16, < 3)
-    mime-types (2.6.1)
-    mini_portile (0.6.2)
-    minitest (5.7.0)
-    multi_json (1.11.1)
-    nokogiri (1.6.6.2)
-      mini_portile (~> 0.6.0)
+    mail (2.6.4)
+      mime-types (>= 1.16, < 4)
+    mime-types (3.1)
+      mime-types-data (~> 3.2015)
+    mime-types-data (3.2016.0521)
+    mini_portile2 (2.1.0)
+    minitest (5.9.0)
+    multi_json (1.12.1)
+    nokogiri (1.6.8)
+      mini_portile2 (~> 2.1.0)
+      pkg-config (~> 1.1.7)
     orm_adapter (0.5.0)
+    pkg-config (1.1.7)
     rack (1.6.4)
     rack-test (0.6.3)
       rack (>= 1.0)
@@ -105,73 +104,70 @@ GEM
       sprockets-rails
     rails-deprecated_sanitizer (1.0.3)
       activesupport (>= 4.2.0.alpha)
-    rails-dom-testing (1.0.6)
+    rails-dom-testing (1.0.7)
       activesupport (>= 4.2.0.beta, < 5.0)
       nokogiri (~> 1.6.0)
       rails-deprecated_sanitizer (>= 1.0.1)
-    rails-html-sanitizer (1.0.2)
+    rails-html-sanitizer (1.0.3)
       loofah (~> 2.0)
     railties (4.2.2)
       actionpack (= 4.2.2)
       activesupport (= 4.2.2)
       rake (>= 0.8.7)
       thor (>= 0.18.1, < 2.0)
-    rake (10.4.2)
-    rdoc (4.2.0)
-    responders (2.1.0)
-      railties (>= 4.2.0, < 5)
-    rspec-core (3.3.2)
-      rspec-support (~> 3.3.0)
-    rspec-expectations (3.3.1)
+    rake (11.2.2)
+    rdoc (4.2.2)
+      json (~> 1.4)
+    responders (2.2.0)
+      railties (>= 4.2.0, < 5.1)
+    rspec-core (3.5.1)
+      rspec-support (~> 3.5.0)
+    rspec-expectations (3.5.0)
       diff-lcs (>= 1.2.0, < 2.0)
-      rspec-support (~> 3.3.0)
-    rspec-mocks (3.3.2)
+      rspec-support (~> 3.5.0)
+    rspec-mocks (3.5.0)
       diff-lcs (>= 1.2.0, < 2.0)
-      rspec-support (~> 3.3.0)
-    rspec-rails (3.3.3)
-      actionpack (>= 3.0, < 4.3)
-      activesupport (>= 3.0, < 4.3)
-      railties (>= 3.0, < 4.3)
-      rspec-core (~> 3.3.0)
-      rspec-expectations (~> 3.3.0)
-      rspec-mocks (~> 3.3.0)
-      rspec-support (~> 3.3.0)
-    rspec-support (3.3.0)
-    sass (3.4.15)
-    sass-rails (5.0.3)
-      railties (>= 4.0.0, < 5.0)
+      rspec-support (~> 3.5.0)
+    rspec-rails (3.5.1)
+      actionpack (>= 3.0)
+      activesupport (>= 3.0)
+      railties (>= 3.0)
+      rspec-core (~> 3.5.0)
+      rspec-expectations (~> 3.5.0)
+      rspec-mocks (~> 3.5.0)
+      rspec-support (~> 3.5.0)
+    rspec-support (3.5.0)
+    sass (3.4.22)
+    sass-rails (5.0.5)
+      railties (>= 4.0.0, < 6)
       sass (~> 3.1)
       sprockets (>= 2.8, < 4.0)
       sprockets-rails (>= 2.0, < 4.0)
-      tilt (~> 1.1)
+      tilt (>= 1.1, < 3)
     sdoc (0.4.1)
       json (~> 1.7, >= 1.7.7)
       rdoc (~> 4.0)
-    spring (1.3.6)
-    sprockets (3.2.0)
-      rack (~> 1.0)
-    sprockets-rails (2.3.2)
-      actionpack (>= 3.0)
-      activesupport (>= 3.0)
-      sprockets (>= 2.8, < 4.0)
-    sqlite3 (1.3.10)
+    spring (1.7.2)
+    sprockets (3.7.0)
+      concurrent-ruby (~> 1.0)
+      rack (> 1, < 3)
+    sprockets-rails (3.1.1)
+      actionpack (>= 4.0)
+      activesupport (>= 4.0)
+      sprockets (>= 3.0.0)
+    sqlite3 (1.3.11)
     thor (0.19.1)
     thread_safe (0.3.5)
-    tilt (1.4.1)
-    turbolinks (2.5.3)
-      coffee-rails
+    tilt (2.0.5)
+    turbolinks (5.0.0)
+      turbolinks-source (~> 5)
+    turbolinks-source (5.0.0)
     tzinfo (1.2.2)
       thread_safe (~> 0.1)
-    uglifier (2.7.1)
-      execjs (>= 0.3.0)
-      json (>= 1.8.0)
-    warden (1.2.3)
+    uglifier (3.0.0)
+      execjs (>= 0.3.0, < 3)
+    warden (1.2.6)
       rack (>= 1.0)
-    web-console (2.1.3)
-      activemodel (>= 4.0)
-      binding_of_caller (>= 0.7.2)
-      railties (>= 4.0)
-      sprockets-rails (>= 2.0, < 4.0)
 
 PLATFORMS
   ruby
@@ -192,7 +188,6 @@ DEPENDENCIES
   sqlite3
   turbolinks
   uglifier (>= 1.3.0)
-  web-console (~> 2.0)
 
 BUNDLED WITH
-   1.10.5
+   1.12.4
diff --git a/app/controllers/api_controller.rb b/app/controllers/api_controller.rb
new file mode 100644
index 0000000..75bb517
--- /dev/null
+++ b/app/controllers/api_controller.rb
@@ -0,0 +1,2 @@
+class ApiController < ActionController::Base
+end
\ No newline at end of file
diff --git a/app/controllers/api_v1/messages_controller.rb b/app/controllers/api_v1/messages_controller.rb
new file mode 100644
index 0000000..3731df9
--- /dev/null
+++ b/app/controllers/api_v1/messages_controller.rb
@@ -0,0 +1,5 @@
+class ApiV1::MessagesController < ApiController
+  def index
+    @message = Message.all
+  end
+end
\ No newline at end of file
diff --git a/app/controllers/comments_controller.rb b/app/controllers/comments_controller.rb
index e9d6aaa..5b024bb 100644
--- a/app/controllers/comments_controller.rb
+++ b/app/controllers/comments_controller.rb
@@ -16,7 +16,10 @@ def destroy
     @comment = current_user.comments.find( params[:id] )
     @comment.destroy
 
-    redirect_to :back
+    respond_to do |format|
+      format.html { redirect_to :back }
+      format.js # destroy.js.erb
+    end
   end
 
   protected
diff --git a/app/controllers/messages_controller.rb b/app/controllers/messages_controller.rb
index 96f65e5..0275b0c 100644
--- a/app/controllers/messages_controller.rb
+++ b/app/controllers/messages_controller.rb
@@ -4,19 +4,19 @@ class MessagesController < ApplicationController
 
   def index
     # TODO: fix N+1 queries for user and comments
-    @messages = Message.order("id DESC").page( params[:page] )
+    @messages = Message.includes(:user,:comments).order("id DESC").page( params[:page] )
 
     if params[:status] == "pending"
       # TODO: @messages = @messages.pending
-      @messages = @messages.where( :status => "pending" )
+      @messages = @messages.pending
     elsif params[:status] == "completed"
       # TODO: @messages = @messages.completed
-      @messages = @messages.where( :status => "completed" )
+      @messages = @messages.completed
     end
 
     if params[:days]
       # TODO: @messages = @messages.within_days(params[:days].to_i)
-      @messages = @messages.where( ["created_at >= ?", Time.now - params[:days].to_i.days ] )
+      @messages = @messages.within_days(params[:days].to_i)
     end
   end
 
diff --git a/app/models/like.rb b/app/models/like.rb
new file mode 100644
index 0000000..3af785e
--- /dev/null
+++ b/app/models/like.rb
@@ -0,0 +1,4 @@
+class Like < ActiveRecord::Base
+  belongs_to :message
+  belongs_to :user
+end
diff --git a/app/models/message.rb b/app/models/message.rb
index e24a8b2..04c1594 100644
--- a/app/models/message.rb
+++ b/app/models/message.rb
@@ -4,6 +4,16 @@ class Message < ActiveRecord::Base
 
   has_many :comments, :dependent => :destroy
 
+  has_many :likes, :dependent => :destroy
+  has_many :likes_by, :through => :likes, :source => :user, :dependent => :destroy
+
+  has_many :subscriptions, :dependent => :destroy
+  has_many :subscriptions_by, :through => :likes, :source => :user, :dependent => :destroy
+
+  scope :pending, -> { where status: "pending" }
+  scope :completed, -> {where status: "completed" }
+  scope :within_days, -> (time){ where "created_at >= ?", Time.now - time.days }
+
   def last_comment_summary
     self.comments.last.try(:content).try(:truncate, 20)
   end
diff --git a/app/models/subscription.rb b/app/models/subscription.rb
new file mode 100644
index 0000000..b312e30
--- /dev/null
+++ b/app/models/subscription.rb
@@ -0,0 +1,4 @@
+class Subscription < ActiveRecord::Base
+  belongs_to :message
+  belongs_to :user
+end
diff --git a/app/models/user.rb b/app/models/user.rb
index 6d01aa9..782cf20 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -7,12 +7,19 @@ class User < ActiveRecord::Base
   has_many :messages
   has_many :comments
 
+  has_many :likes, :dependent => :destroy
+  has_many :like_messages, :through => :likes, :source => :message, :dependent => :destroy
+
+  has_many :subscriptions, :dependent => :destroy
+  has_many :subscriptions_by, :through => :likes, :source => :message, :dependent => :destroy
+
+
   def display_name
     self.email.split("@").first
   end
 
   def posts_count
-    # TODO: 請完成我
+    self.messages.count + self.comments.count
   end
 
   def words_count
diff --git a/app/views/api_v1/messages/index.json.jbuilder b/app/views/api_v1/messages/index.json.jbuilder
new file mode 100644
index 0000000..d13131c
--- /dev/null
+++ b/app/views/api_v1/messages/index.json.jbuilder
@@ -0,0 +1,10 @@
+json.data do
+  json.array!(@message) do |message|
+    json.id message.id
+    json.status message.status
+    json.category_name message.category_name
+    json.title message.title
+    json.content message.content
+    json.created_at message.created_at
+  end
+end
\ No newline at end of file
diff --git a/app/views/comments/destroy.js.erb b/app/views/comments/destroy.js.erb
new file mode 100644
index 0000000..e02f77e
--- /dev/null
+++ b/app/views/comments/destroy.js.erb
@@ -0,0 +1 @@
+$("#comment-<%= @comment.id %>").remove();
\ No newline at end of file
diff --git a/app/views/messages/show.html.erb b/app/views/messages/show.html.erb
index 41401f6..66cfb79 100644
--- a/app/views/messages/show.html.erb
+++ b/app/views/messages/show.html.erb
@@ -2,6 +2,15 @@
 
 <%= simple_format @message.content %>
 
+<h4>Likes</h4>
+<% @message.likes_by.each do |user| %>
+    <p><%= user.email.split("@").first%></p>
+<% end %>
+<h4>Subscribed</h4>
+<% @message.subscriptions_by.each do |user| %>
+   <p><%= user.email.split("@").first%></p>
+<% end %>
+
 <h2>Comments list</h2>
 
 <%= form_for [@message, @comment] do |f| %>
@@ -18,14 +27,15 @@
 <% end %>
 
 <% @message.comments.each do |comment| %>
-
+  <div id ="comment-<%= comment.id %>">
   <p><%= simple_format comment.content %> at <%= comment.created_at.to_s(:short) %> by <%= comment.user.display_name %>
 
     <% if comment.user == current_user %>
       <%# TODO: 修改成 AJAX 版本的刪除 %>
-      <%= link_to "Delete", message_comment_path(@message, comment), :method => :delete, :data => { :confirm => "Are u sure?"} %>
+      <%= link_to "Delete", message_comment_path(@message, comment), :method => :delete, :remote => true %>
     <% end %>
   </p>
+  </div>
 
 <% end %>
 
diff --git a/config/application.rb b/config/application.rb
index 4d3aa47..9ebd74d 100644
--- a/config/application.rb
+++ b/config/application.rb
@@ -1,7 +1,7 @@
 require File.expand_path('../boot', __FILE__)
 
 require 'rails/all'
-
+require 'yaml'
 # Require the gems listed in Gemfile, including any gems
 # you've limited to :test, :development, or :production.
 Bundler.require(*Rails.groups)
diff --git a/config/routes.rb b/config/routes.rb
index 74d4dbf..a2eac1d 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -5,6 +5,10 @@
     resources :comments
   end
 
+  scope :path => '/api/v1/', :module => "api_v1", :as => 'v1', :defaults => {:format => :json} do
+    resources :messages
+  end
+
   # The priority is based upon order of creation: first created -> highest priority.
   # See how all your routes lay out with "rake routes".
 
diff --git a/db/migrate/20160722082411_create_subscriptions.rb b/db/migrate/20160722082411_create_subscriptions.rb
new file mode 100644
index 0000000..6555f86
--- /dev/null
+++ b/db/migrate/20160722082411_create_subscriptions.rb
@@ -0,0 +1,11 @@
+class CreateSubscriptions < ActiveRecord::Migration
+  def change
+    create_table :subscriptions do |t|
+
+      t.integer :user_id, index: :true
+      t.integer :message_id, index: :true
+
+      t.timestamps null: false
+    end
+  end
+end
diff --git a/db/migrate/20160722082420_create_likes.rb b/db/migrate/20160722082420_create_likes.rb
new file mode 100644
index 0000000..3ecdab6
--- /dev/null
+++ b/db/migrate/20160722082420_create_likes.rb
@@ -0,0 +1,11 @@
+class CreateLikes < ActiveRecord::Migration
+  def change
+    create_table :likes do |t|
+
+      t.integer :user_id, index: :true
+      t.integer :message_id, index: :true
+
+      t.timestamps null: false
+    end
+  end
+end
diff --git a/db/schema.rb b/db/schema.rb
index ef7b5c0..2090cb8 100644
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -11,7 +11,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 20150728165437) do
+ActiveRecord::Schema.define(version: 20160722082420) do
 
   create_table "comments", force: :cascade do |t|
     t.text     "content"
@@ -23,6 +23,16 @@
 
   add_index "comments", ["message_id"], name: "index_comments_on_message_id"
 
+  create_table "likes", force: :cascade do |t|
+    t.integer  "user_id"
+    t.integer  "message_id"
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+  end
+
+  add_index "likes", ["message_id"], name: "index_likes_on_message_id"
+  add_index "likes", ["user_id"], name: "index_likes_on_user_id"
+
   create_table "messages", force: :cascade do |t|
     t.string   "title"
     t.text     "content"
@@ -36,6 +46,16 @@
   add_index "messages", ["status"], name: "index_messages_on_status"
   add_index "messages", ["user_id"], name: "index_messages_on_user_id"
 
+  create_table "subscriptions", force: :cascade do |t|
+    t.integer  "user_id"
+    t.integer  "message_id"
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+  end
+
+  add_index "subscriptions", ["message_id"], name: "index_subscriptions_on_message_id"
+  add_index "subscriptions", ["user_id"], name: "index_subscriptions_on_user_id"
+
   create_table "users", force: :cascade do |t|
     t.string   "email",                  default: "", null: false
     t.string   "encrypted_password",     default: "", null: false
diff --git a/lib/tasks/dev.rake b/lib/tasks/dev.rake
index 4673e72..b41b88c 100644
--- a/lib/tasks/dev.rake
+++ b/lib/tasks/dev.rake
@@ -17,6 +17,12 @@ namespace :dev do
                            :content => Faker::Lorem.paragraph,
                            :user => users.sample,
                            :created_at => Time.now - rand(30).days )
+        users.sample(2).each do |u|
+          Subscription.create!(:user => u, :message => m)
+        end
+        users.sample(2).each do |u|
+          Like.create!(:user => u, :message => m)
+        end
       5.times do
         m.comments.create!( :content => Faker::Lorem.paragraph,
                             :user => users.sample )
diff --git a/spec/models/like_spec.rb b/spec/models/like_spec.rb
new file mode 100644
index 0000000..76ea93d
--- /dev/null
+++ b/spec/models/like_spec.rb
@@ -0,0 +1,5 @@
+require 'rails_helper'
+
+RSpec.describe Like, type: :model do
+  pending "add some examples to (or delete) #{__FILE__}"
+end
diff --git a/spec/models/subscription_spec.rb b/spec/models/subscription_spec.rb
new file mode 100644
index 0000000..d40bf0b
--- /dev/null
+++ b/spec/models/subscription_spec.rb
@@ -0,0 +1,5 @@
+require 'rails_helper'
+
+RSpec.describe Subscription, type: :model do
+  pending "add some examples to (or delete) #{__FILE__}"
+end
diff --git a/spec/models/user_spec.rb b/spec/models/user_spec.rb
index 528cc38..880d358 100644
--- a/spec/models/user_spec.rb
+++ b/spec/models/user_spec.rb
@@ -25,10 +25,25 @@
   describe "#words_count" do
     before do
       # TODO: 加 Message 和 Comment 測試資料
+      @other_user = User.create!(:email => "ooxx@example.org", :password => "12345678")
+
+      m1 =Message.create!(:user => @user,
+                          :title => Faker::Lorem.words(10),
+                          :content => Faker::Lorem.words(20))
+      Comment.create!(:user => @other_user,
+                      :content => Faker::Lorem.words(20),
+                      :message_id => m1)
+      Comment.create!(:user => @user,
+                      :content => Faker::Lorem.words(15),
+                      :message_id => m1)
+      # 共45字 for @user
+      # 共20字 for @other_user
     end
 
     it "加總該使用者的所有 Mesasge 和 Comment 的總字數" do
       # TODO: 測試 words_count 方法
+      expect(@user.words_count).to eq(45)
+      expect(@other_user.words_count).to eq(20)
 
     end
   end