Chore: Enable Users to create multiple accounts (#440)

Addresses: #402
- migrations to split roles and other attributes from users table
- make changes in code to accommodate this change

Co-authored-by: Sojan Jose <sojan@pepalo.com>
Co-authored-by: Pranav Raj Sreepuram <pranavrajs@gmail.com>

app/controllers/api/v1/agents_controller.rb

@@ -1,25 +1,27 @@
 class Api::V1::AgentsController < Api::BaseController
   before_action :fetch_agent, except: [:create, :index]
   before_action :check_authorization
-  before_action :build_agent, only: [:create]
+  before_action :find_user, only: [:create]
+  before_action :create_user, only: [:create]
+  before_action :save_account_user, only: [:create]
 
   def index
     @agents = agents
   end
 
   def destroy
-    @agent.destroy
+    @agent.account_user.destroy
     head :ok
   end
 
   def update
-    @agent.update!(agent_params)
-    render json: @agent
+    @agent.update!(agent_params.except(:role))
+    @agent.account_user.update!(role: agent_params[:role]) if agent_params[:role]
+    render 'api/v1/models/user.json', locals: { resource: @agent }
   end
 
   def create
-    @agent.save!
-    render json: @agent
+    render 'api/v1/models/user.json', locals: { resource: @user }
   end
 
   private
@@ -32,8 +34,23 @@ class Api::V1::AgentsController < Api::BaseController
     @agent = agents.find(params[:id])
   end
 
-  def build_agent
-    @agent = agents.new(new_agent_params)
+  def find_user
+    @user =  User.find_by(email: new_agent_params[:email])
+  end
+
+  def create_user
+    return if @user
+
+    @user = User.create!(new_agent_params.slice(:email, :name, :password, :password_confirmation))
+  end
+
+  def save_account_user
+    AccountUser.create!(
+      account_id: current_account.id,
+      user_id: @user.id,
+      role: new_agent_params[:role],
+      inviter_id: current_user.id
+    )
   end
 
   def agent_params