From 70feaf07f64574a1775ece20e197dcc4bb257ed2 Mon Sep 17 00:00:00 2001
From: Rei <chloerei@gmail.com>
Date: Tue, 14 Jan 2014 22:41:19 +0800
Subject: [PATCH] posts#vote action

---
 app/controllers/posts_controller.rb       | 14 ++++++++++++++
 app/models/post.rb                        |  1 +
 app/models/post_vote.rb                   | 13 ++++++++++---
 config/routes.rb                          |  4 ++++
 test/controllers/posts_controller_test.rb | 14 ++++++++++++++
 test/factories/post_votes.rb              |  1 +
 test/models/post_vote_test.rb             |  6 ++++++
 7 files changed, 50 insertions(+), 3 deletions(-)

diff --git a/app/controllers/posts_controller.rb b/app/controllers/posts_controller.rb
index 60c88d7..14519ea 100644
--- a/app/controllers/posts_controller.rb
+++ b/app/controllers/posts_controller.rb
@@ -40,6 +40,20 @@ class PostsController < ApplicationController
     render layout: false
   end
 
+  def vote
+    @post = Post.find_by! id: params[:id]
+    if PostVote::VALUE.keys.include? params[:type]
+      post_vote = @post.post_votes.find_or_initialize_by(user_id: current_user.id)
+      post_vote.update_attribute :value, params[:type]
+    elsif params[:type] == 'cancel'
+      @post.post_votes.find_by(user_id: current_user.id).try(:destroy)
+    end
+
+    respond_to do |format|
+      format.js { render :show }
+    end
+  end
+
   private
 
   def post_params
diff --git a/app/models/post.rb b/app/models/post.rb
index 45a8b4a..55c01da 100644
--- a/app/models/post.rb
+++ b/app/models/post.rb
@@ -1,6 +1,7 @@
 class Post < ActiveRecord::Base
   belongs_to :topic
   belongs_to :user
+  has_many :post_votes
 
   after_create :get_post_number
 
diff --git a/app/models/post_vote.rb b/app/models/post_vote.rb
index ad27289..b43cceb 100644
--- a/app/models/post_vote.rb
+++ b/app/models/post_vote.rb
@@ -5,11 +5,18 @@ class PostVote < ActiveRecord::Base
 
   validates :value, presence: true
 
-  after_save :update_post_votes
+  after_create do
+    post.increment! :votes, VALUE[value]
+  end
 
-  def update_post_votes
+  after_update do
     if value_changed?
-      post.increment! :votes, VALUE[value]
+      # TODO value and value_was type is different, maybe change later.
+      post.increment! :votes, (VALUE[value] - value_was)
     end
   end
+
+  after_destroy do
+    post.decrement! :votes, VALUE[value]
+  end
 end
diff --git a/config/routes.rb b/config/routes.rb
index 2d1068f..d1b69d2 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -19,5 +19,9 @@ Rails.application.routes.draw do
     collection do
       post 'preview'
     end
+
+    member do
+      patch :vote
+    end
   end
 end
diff --git a/test/controllers/posts_controller_test.rb b/test/controllers/posts_controller_test.rb
index a2bb696..5810bc1 100644
--- a/test/controllers/posts_controller_test.rb
+++ b/test/controllers/posts_controller_test.rb
@@ -34,4 +34,18 @@ class PostsControllerTest < ActionController::TestCase
     assert_response :success, @response.body
     assert_equal 'change', topic_post.reload.content
   end
+
+  test "should vote post" do
+    topic_post = create(:post)
+    assert_require_logined do
+      xhr :patch, :vote, id: topic_post, type: 'up'
+    end
+    assert_equal 1, topic_post.reload.votes
+
+    xhr :patch, :vote, id: topic_post, type: 'down'
+    assert_equal(-1, topic_post.reload.votes)
+
+    xhr :patch, :vote, id: topic_post, type: 'cancel'
+    assert_equal(0, topic_post.reload.votes)
+  end
 end
diff --git a/test/factories/post_votes.rb b/test/factories/post_votes.rb
index 8b1a4b5..fe94654 100644
--- a/test/factories/post_votes.rb
+++ b/test/factories/post_votes.rb
@@ -2,5 +2,6 @@ FactoryGirl.define do
   factory :post_vote do
     user
     post
+    value 'up'
   end
 end
diff --git a/test/models/post_vote_test.rb b/test/models/post_vote_test.rb
index 3119ff7..e30e516 100644
--- a/test/models/post_vote_test.rb
+++ b/test/models/post_vote_test.rb
@@ -26,6 +26,12 @@ class PostVoteTest < ActiveSupport::TestCase
     assert_equal 1, post.votes
 
     vote.update_attribute :value, 'down'
+    assert_equal(-1, post.votes)
+
+    vote.update_attribute :value, 'up'
+    assert_equal 1, post.votes
+
+    vote.destroy
     assert_equal 0, post.votes
   end
 end