trabajo-afectivo/app/models/store.rb

require 'digest/md5'

class Store < ActiveRecord::Base
  store       :preferences
  belongs_to  :store_object,          :class_name => 'Store::Object'
  belongs_to  :store_file,            :class_name => 'Store::File'
  validates   :filename,              :presence => true

  def self.add(data)
    data = data.stringify_keys

    # lookup store_object.id
    store_object = Store::Object.where( :name => data['object'] ).first
    if !store_object || !store_object.id
      store_object = Store::Object.create(
        :name   => data['object']
      )
    end
    data['store_object_id'] = store_object.id

    # check if record already exists
#    store = Store.where( :store_object_id => store_object.id, :o_id => data['o_id'],  ).first
#    if store != nil
#      return store
#    end

    # check real store
    md5 = Digest::MD5.hexdigest( data['data'] )
    data['size'] = data['data'].to_s.to_blob.bytesize

    file = Store::File.where( :md5 => md5 ).first

    # store attachment
    if file == nil
      file = Store::File.create(
        :data => data['data'],
        :md5  => md5
      )
    end

    data['store_file_id'] = file.id
    data['created_by_id'] = 1

    # not needed attributes
    data.delete('data')
    data.delete('object')

    # store meta data
    store = Store.create(data)

    return store
  end

  def self.list(data)
    # search
    stores = Store.where( :store_object_id => Store::Object.where( :name => data[:object] ), :o_id => data[:o_id].to_i ).
      order('created_at ASC, id ASC')
    return stores
  end

  def self.remove(data)
    # search
    stores = Store.where( :store_object_id => Store::Object.where( :name => data[:object] ) ).
      where( :o_id => data[:o_id] ).
      order('created_at ASC, id ASC')
    stores.each do |store|
      store.destroy
    end
    return true
  end

  class Object < ActiveRecord::Base
    validates :name, :presence => true
  end

  class File < ActiveRecord::Base
    before_validation :add_md5

    private
      def add_md5
        self.md5 = Digest::MD5.hexdigest( self.data )
      end
  end

end