Creating badge and achievements functionality in Ruby on Rails

badge_creator.rb

#Step 1 - Create achievement, badge, and user models  

#Create an Achivement model
#This will contain all of the achievements 

#model
class Achievement < ActiveRecord::Base
  has_many :badges
  has_many :users, through: :badges
end

#table
class CreateAchievements < ActiveRecord::Migration
  def change
    create_table :achievements do |t|
      t.text :identity, unique: true, index: true  #this is so you dont have to  memorize index values
      t.text :name
      t.timestamps null: false
    end
  end
end


#Create Badge model 
#As achievements can belong to many users, and users can have many achievements, 
#the badge model will serve as the join table 
#(a user gets a badge when an achievement is met, so I chose the word badge to represent this)

class Badge < ActiveRecord::Base
  belongs_to :user
  belongs_to :achievement	
end

#table
class CreateBadges < ActiveRecord::Migration
  def change
    create_table :badges do |t|
      t.references :user
      t.references :achievement
      t.timestamps null: false
    end
  end
end

#Create a User model:
class User < ActiveRecord::Base
  has_many :badges, dependent: :destroy
  has_many :achievements, through: :badges
end


#Step 2 - Create a module in Controller concerns directory

#Achievements are typically created inside controller actions, 
#For example, if a user completes x amount of goals, or tasks. 
#This module checks the conditions needed to create a new badge, if they are met, 
#the badge is created and a message is added to flash.  Include the module in 
#the controllers and call it with check_achievement(type) - the 'type' argument is the name of the controller.

module BadgeCreator
  
  def check_achievements(type)
    send((type + '_achievements').to_sym)
  end

  def create_badge(type, name)
    return if achievement_already_reached?(type)
    id = Achievement.find_by_identity(type).id
    current_user.badges.create(achievement_id: id)
    flash[:achievement] = name 
  end

  def achievement_already_reached?(type)
    current_user.achievements.exists?(identity: type) 
  end

  #This is where you create the custom achievement logic - each method corresponds to a controller
  #to do: relocate this section - to their own files/module?
  
  def task_achievements()
    #condition(s)
    task_count = current_user.tasks.count_completed(current_user)  
    #achievements
    create_badge('10 tasks', 'Complete 10 tasks')      if task_count >= 10
    create_badge('100 tasks', 'Complete 100 tasks')    if task_count >= 100
    create_badge('1000 tasks', 'Complete 1000 tasks')  if task_count >= 1000
  end
end


class TasksController < ApplicationController
  include BadgeCreator
  
  ...
  def update
    ...
    if @task.save
      #Achievement   
      check_achievements("task") #call the method wherever it is needed inside your controller. 
                                 #the argument is needed to identify the controller. In this example 
                                 #the #task_achievements() method would be called
      ...
    end
    ...
  end
  ...
end