module Locomotive
  class ThemeAsset

    include Locomotive::Mongoid::Document

    ## extensions ##
    include Concerns::Shared::SiteScope
    include Concerns::Asset::Types
    include Concerns::Asset::Checksum

    ## fields ##
    field :local_path
    field :content_type,  type: Symbol
    field :width,         type: Integer
    field :height,        type: Integer
    field :size,          type: Integer
    field :folder,        default: nil

    mount_uploader :source, ThemeAssetUploader, mount_on: :source_filename, validate_integrity: true

    # indexes
    index site_id: 1, local_path: 1

    ## callbacks ##
    before_validation :check_for_folder_changes
    before_validation :sanitize_folder
    before_validation :build_local_path

    ## validations ##
    validates_presence_of   :source, on: :create
    validates_uniqueness_of :local_path, scope: :site_id

    ## named scopes ##

    ## methods ##

    def touch_site_attribute
      :template_version
    end

    def stylesheet_or_javascript?
      self.stylesheet? || self.javascript?
    end

    def local_path(short = false)
      if short && self.read_attribute(:local_path)
        self.read_attribute(:local_path).split('/')[1..-1].join('/')
      else
        self.read_attribute(:local_path)
      end
    end

    def self.all_grouped_by_folder(site)
      assets = site.theme_assets.order_by(:slug.asc)
      assets.group_by { |a| a.folder.split('/').first.to_sym }
    end

    def self.checksums
      {}.tap do |hash|
        self.only(:local_path, :checksum).each do |asset|
          hash[asset.local_path] = asset.checksum
        end
      end
    end

    protected

    def safe_source_filename
      self.source_filename || self.source.send(:original_filename) rescue nil
    end

    def sanitize_folder
      self.folder = self.content_type.to_s.pluralize if self.folder.blank?

      # no accents, no spaces, no leading and ending trails
      self.folder = ActiveSupport::Inflector.transliterate(self.folder).gsub(/(\s)+/, '_').gsub(/^\//, '').gsub(/\/$/, '')

      # folder should begin by a root folder
      if (self.folder =~ /^(stylesheets|javascripts|images|media|fonts|pdfs|others|misc)($|\/)+/).nil?
        self.folder = File.join(self.content_type.to_s.pluralize, self.folder)
      end
    end

    def build_local_path
      if filename = self.safe_source_filename
        self.local_path = File.join(self.folder, filename)
      else
        nil
      end
    end

    def check_for_folder_changes
      # https://github.com/jnicklas/carrierwave/issues/330
      # https://github.com/jnicklas/carrierwave-mongoid/issues/23
      if self.persisted? && self.folder_changed? && !self.changed_attributes.key?('source_filename')
        # a simple way to rename a file
        old_asset         = self.class.where(_id: self._id).first # bypass memoization by mongoid
        file              = old_asset.source.file
        file.content_type = File.mime_type?(file.path) if file.content_type.nil?
        self.source       = file
        self.changed_attributes['source_filename'] = nil # delete the old file
      end
    end

  end
end