Class: EasyTag::Attributes::MP3Attribute

Inherits:
BaseAttribute show all
Defined in:
lib/easytag/attributes/mp3.rb

Constant Summary

Constants inherited from BaseAttribute

BaseAttribute::Utilities

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods inherited from BaseAttribute

#call, can_clone?, deep_copy, #default, name_to_ivar, obj_or_nil, #post_process, #type_cast

Constructor Details

#initialize(args) ⇒ MP3Attribute

Returns a new instance of MP3Attribute.



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# File 'lib/easytag/attributes/mp3.rb', line 11

def initialize(args)
  super(args)
  @id3v2_frames = args[:id3v2_frames] || []
  @id3v1_tag    = args[:id3v1_tag] || nil

  # fill default options

  # ID3 stores boolean values as numeric strings
  #   set to true to enable type casting  (post process)
  @options[:is_flag]    ||= false
  # return entire field list instead of first item in field list
  @options[:field_list] ||= false
end

Instance Attribute Details

#ivar ⇒ Object (readonly)

Returns the value of attribute ivar.



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# File 'lib/easytag/attributes/mp3.rb', line 9

def ivar
  @ivar
end

#name ⇒ Object (readonly)

Returns the value of attribute name.



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# File 'lib/easytag/attributes/mp3.rb', line 9

def name
  @name
end

Instance Method Details

#data_from_frame(frame) ⇒ Object 



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# File 'lib/easytag/attributes/mp3.rb', line 34

def data_from_frame(frame)
  data = nil
  if frame.is_a?(TagLib::ID3v2::TextIdentificationFrame)
    field_list = frame.field_list
    data = @options[:field_list] ? field_list : field_list.first
  elsif frame.is_a?(TagLib::ID3v2::UnsynchronizedLyricsFrame)
    data = frame.text
  elsif frame.is_a?(TagLib::ID3v2::CommentsFrame)
    data = frame.text
  elsif frame.is_a?(TagLib::ID3v2::AttachedPictureFrame)
    data = EasyTag::Image.new(frame.picture)
    data.desc = frame.description
    data.type = frame.type
    data.mime_type = frame.mime_type
  else
    warn 'no defined frames match the given frame'
  end

  data
end

#first_frame_for_id(id, iface) ⇒ Object 



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# File 'lib/easytag/attributes/mp3.rb', line 30

def first_frame_for_id(id, iface)
  frames_for_id(id, iface).first
end

#frames_for_id(id, iface) ⇒ Object 



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# File 'lib/easytag/attributes/mp3.rb', line 26

def frames_for_id(id, iface)
  iface.info.id3v2_tag.frame_list(id)
end

#read_all_id3(iface) ⇒ Object

read_all_id3

gets data from each frame id given only falls back to the id3v1 tag if none found



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# File 'lib/easytag/attributes/mp3.rb', line 63

def read_all_id3(iface)
  frames = []
  @id3v2_frames.each do |f| 
    frames += frames_for_id(f, iface)
  end

  data = []
  # only check id3v1 if no id3v2 frames found
  if frames.empty?
    data << iface.info.id3v1_tag.send(@id3v1_tag) unless @id3v1_tag.nil?
  else
    frames.each { |frame| data << data_from_frame(frame) }
  end

  data
end

#read_date(iface) ⇒ Object 



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# File 'lib/easytag/attributes/mp3.rb', line 117

def read_date(iface)
  id3v1 = iface.info.id3v1_tag

  v10_year = id3v1.year.to_s if id3v1.year > 0
  v23_year = data_from_frame(first_frame_for_id('TYER', iface))
  v23_date = data_from_frame(first_frame_for_id('TDAT', iface))
  v24_date = data_from_frame(first_frame_for_id('TDRC', iface))

  # check variables in order of importance
  date_str = v24_date || v23_year || v10_year
  # only append v23_date if date_str is currently a year
  date_str << v23_date unless v23_date.nil? or date_str.length > 4
  puts "MP3#date: date_str = \"#{date_str}\"" if $DEBUG

  date_str
end

#read_field_list_as_key_value(iface) ⇒ Object 



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# File 'lib/easytag/attributes/mp3.rb', line 103

def read_field_list_as_key_value(iface)
  kv_hash = {}
  frame_data = read_all_id3(iface)

  frame_data.each do |data|
    key, value = data
    key = Utilities.normalize_string(key) if @options[:normalize]
    key = key.to_sym if @options[:to_sym]
    kv_hash[key] = value
  end

  kv_hash
end

#read_first_id3(iface) ⇒ Object

read_first_id3

Similar to read_all_id3, but optimized for reading only one frame at max



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# File 'lib/easytag/attributes/mp3.rb', line 83

def read_first_id3(iface)
  frame = nil
  @id3v2_frames.each do |f|
    frame = first_frame_for_id(f, iface) if frame.nil?
  end

  if frame.nil?
    data = iface.info.id3v1_tag.send(@id3v1_tag) unless @id3v1_tag.nil?
  else
    data = data_from_frame(frame)
  end

  data
end

#read_int_pair(iface) ⇒ Object 



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# File 'lib/easytag/attributes/mp3.rb', line 98

def read_int_pair(iface)
  int_pair_str = read_first_id3(iface).to_s
  EasyTag::Utilities.get_int_pair(int_pair_str)
end