Site customization: images uploads

app/models/site_customization/image.rb

@@ -0,0 +1,48 @@
+class SiteCustomization::Image < ActiveRecord::Base
+  VALID_IMAGES = {
+    "icon_home" => [330, 240],
+    "logo_header" => [80, 80],
+    "social-media-icon" => [200, 200],
+    "apple-touch-icon-200" => [200, 200]
+  }
+
+  has_attached_file :image
+
+  validates :name, presence: true, uniqueness: true, inclusion: { in: VALID_IMAGES.keys }
+  validates_attachment_content_type :image, :content_type => ["image/png"]
+  validate :check_image
+
+  def self.all_images
+    VALID_IMAGES.keys.map do |image_name|
+      find_by(name: image_name) || create!(name: image_name.to_s)
+    end
+  end
+
+  def self.image_path_for(filename)
+    image_name = filename.split(".").first
+
+    if i = find_by(name: image_name)
+      i.image.exists? ? i.image.url : nil
+    end
+  end
+
+  def required_width
+    VALID_IMAGES[name].try(:first)
+  end
+
+  def required_height
+    VALID_IMAGES[name].try(:second)
+  end
+
+  private
+
+    def check_image
+      return unless image?
+
+      dimensions = Paperclip::Geometry.from_file(image.queued_for_write[:original].path)
+
+      errors.add(:image, :image_width, required_width: required_width) unless dimensions.width == required_width
+      errors.add(:image, :image_height, required_height: required_height) unless dimensions.height == required_height
+    end
+
+end