rosa-build/app/helpers/users_helper.rb

# -*- encoding : utf-8 -*-
module UsersHelper

  def avatar_url_by_email(email, size = :small)
    avatar_url(User.where(:email => email).first || User.new(:email => email), size)
  end

  def avatar_url(subject, size = :small)
    if subject.try('avatar?')
      subject.avatar.url(size)
    elsif subject.kind_of? Group
      image_path('ava-big.png')
    else
      gravatar_url(subject.email, subject.avatar.styles[size].geometry.split('x').first)
    end
  end

  def gravatar_url(email, size = 30)
    "https://secure.gravatar.com/avatar/#{Digest::MD5.hexdigest(email.downcase)}?s=#{size}&r=pg"
  end
end