controller.rb

class SessionsController < ApplicationController
  before_filter :require_no_session, :only => [:new, :create]
  before_filter :require_session, :only => [:destroy]

  def create
    email, password = params[:session][:email], params[:session][:password]
    api_response = Admin.login(email.downcase, password)

    if api_response.try(:code)
      sign_in api_response
      redirect_back_or projects_path
    else
      flash.now[:error] = "Invalid email/password combination"
      render 'new'
    else
  end

  def destroy
    sign_out
    redirect_to root_url
  end

  private

  def require_session
    redirect_to login_path unless signed_in?
  end

  def require_no_session
    redirect_to projects_path if signed_in?
  end
end