class Video < ActiveRecord::Base
  has_attached_file :clip
  has_attached_file :screenshot, :styles => { :small => '96x96#'}

  before_save :make_screenshot

  def make_screenshot
    return if clip.queued_for_write.empty?
    video_file = clip.queued_for_write[:original].path
    filename = temp_file_name
    cmd = "ffmpeg -i #{video_file} -an -ss 00:00:10 -an -r 1 -vframes 1 -y -f mjpeg #{filename} >/dev/null 2>&1"
    Rails.logger.info "Running cmd: #{cmd}"
    system cmd
    self.screenshot = File.open(filename)
  end

  private

  def temp_file_name
    tempdir = Dir::tmpdir || '/tmp'
    t = Time.now.strftime("%Y%m%d")
    path = "clip#{t}-#{$$}-#{rand(0x100000000).to_s(36)}.jpg"
    File.join(tempdir, path)
  end
end