class Work < ActiveRecord::Base
  belongs_to :medium

  validates_presence_of :filename, :message => "is blank, indicating that no file was selected to be uploaded."
  validates_uniqueness_of :filename, :message => "already exists, try uploading another file or deleting first."
  validates_format_of :pagenumber, :with => /\d+[A-Za-z]+?/, :allow_nil => true, :message => 'must be digits followed by letters.'

  def before_validation
    if self.title.nil? || self.title.empty?
      self.title = 'Untitled'
    end
    if self.pagenumber == ''
      self.pagenumber = nil
    end
    if self.size.nil? || self.title.empty?
      self.size = nil
    end
  end

  def file=(uploaded_file)
    @uploaded_file = uploaded_file
    fn=self.filename=sanitize_filename(File.basename(@uploaded_file.path))
    fn = fn.to_s if File.exists?(self.path_to_tempfile)
    fn = fn.split('_')
    fn.pop
    self.filename = fn.join('_')
  end

  def before_create
    require 'ImageUpload'
    File.open(self.path_to_tempfile, "w") { |f| f.write(@uploaded_file.read) }

    full = ImageUpload::upload_image(self.path_to_tempfile, self.filename, 'full', 'exhibition', 720, 600)
    medium = ImageUpload::upload_image(self.path_to_tempfile, self.filename, 'med', 'exhibition', 600, 500)
    thumb = ImageUpload::upload_image(self.path_to_tempfile, self.filename, 'thumb', 'exhibition', 200, 167)

    File.delete(self.path_to_tempfile)
  end

  def before_destroy
    # delete the file from the filesystem
    File.delete self.path_to_images + self.filename + '_full.jpg'
    File.delete self.path_to_images + self.filename + '_med.jpg'
    File.delete self.path_to_images + self.filename + '_thumb.jpg'
  end

  protected
  def sanitize_filename(value)
    just_filename = value.gsub(/^.*(\\|\/)/, '')
    just_filename.gsub(/[\W]/,'_')
  end

  def path_to_tempfile
    RAILS_ROOT + '/public/images/exhibition/' + self.filename + '_temp.jpg'
  end

  def path_to_images
    RAILS_ROOT + '/public/images/exhibition/'
  end
end


class ImageUpload
  def ImageUpload.upload_image(uploaded_file, filename, imagetype, category, maxwidth = 10000, maxheight = 100000)
    require 'RMagick'
    aspectratio = maxwidth.to_f / maxheight.to_f
    #pic = Magick::Image.read(imgfile).first
    pic = Magick::Image.read(uploaded_file).first
    imgwidth = pic.columns
    imgheight = pic.rows
    if (imgwidth > maxwidth) || (imgheight > maxheight)
      imgratio = imgwidth.to_f / imgheight.to_f
      imgratio > aspectratio ? scaleratio = maxwidth.to_f / imgwidth : scaleratio = maxheight.to_f / imgheight
      pic.thumbnail!(scaleratio)
    end
    pic.write(RAILS_ROOT + "/public/images/" + category + '/' + filename + '_' + imagetype + '.jpg')
  end
end