require 'digest/md5'

module AudioLib

  # Currently only checks for mp3 and m4a files
  def self.is_audio_file?(file_name)
    File.file?(file_name) && File.basename(file_name) =~ AudioLib.file_format[:regexp]
  end

  def self.file_format
    {
      :regexp => /^[-a-z0-9 ]+\.(mp3|m4a)$/i,
      :glob => "*.m[p4][34a]"
    }
  end

  class AudioFile
    attr_accessor :full_path, :name, :hash_name

    def self.find(options={})
      # Determine the group or path to search
      if options.include? :group
        path = options[:group].full_path
      elsif options.include? :path
        path = options[:path]
      else
        raise ArgumentError, "You must specify the :group or :path to search."
      end

      # Determine the name glob to use
      if options.include? :name
        name_glob = options[:name]
      else
        name_glob = AudioLib.file_format[:glob]
      end

      if options.include? :recursive
        path = File.join(path, "**")
      end

      file_glob = File.join(path, name_glob)
      print "file glob #{file_glob}"

      # Walk the file tree
      files = Dir[file_glob].map do |file|
        unless file.nil? || !AudioLib.is_audio_file?(file)
          AudioLib::AudioFile.new(file)
        end
      end
      files.uniq!
      files.delete nil

      if options.include? :name
        unless files.nil? || files.empty?
          files[0]
        else
          nil
        end
      else
        files
      end

    end

    # Initializes a new file based on a full_path name.
    # The file folder must be a valid file and match a specific named format
    def initialize(file_path)
      raise ArgumentError, "File name or path is invalid" unless AudioLib.is_audio_file?(file_path)

      @full_path = File.expand_path file_path
      @name = File.basename file_path
    end

    def size
      File.size @full_path
    end

  end

end