Class: Cabriolet::Models::KWAJHeader

Inherits:
Object
  • Object
show all
Defined in:
lib/cabriolet/models/kwaj_header.rb

Overview

Represents a KWAJ file header

KWAJ files support multiple compression methods and optional headers determined by flag bits. The header structure is more flexible than SZDD.

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize ⇒ KWAJHeader

Initialize a new KWAJ header



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# File 'lib/cabriolet/models/kwaj_header.rb', line 39

def initialize
  @comp_type = Constants::KWAJ_COMP_NONE
  @data_offset = 0
  @headers = 0
  @length = nil
  @filename = nil
  @extra = nil
  @extra_length = 0
end

Instance Attribute Details

#comp_type ⇒ Integer

Compression type

Returns:

  • (Integer) —

    One of KWAJ_COMP_* constants



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# File 'lib/cabriolet/models/kwaj_header.rb', line 12

def comp_type
  @comp_type
end

#data_offset ⇒ Integer

Offset to compressed data

Returns:

  • (Integer) —

    Byte offset where compressed data starts



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# File 'lib/cabriolet/models/kwaj_header.rb', line 16

def data_offset
  @data_offset
end

#extra ⇒ String?

Extra text data

Returns:

  • (String, nil) —

    Extra text data if present



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# File 'lib/cabriolet/models/kwaj_header.rb', line 32

def extra
  @extra
end

#extra_length ⇒ Integer

Length of extra data

Returns:

  • (Integer) —

    Number of bytes in extra data



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# File 'lib/cabriolet/models/kwaj_header.rb', line 36

def extra_length
  @extra_length
end

#filename ⇒ String?

Original filename

Returns:

  • (String, nil) —

    Original filename if present



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# File 'lib/cabriolet/models/kwaj_header.rb', line 28

def filename
  @filename
end

#headers ⇒ Integer

Header flags

Returns:

  • (Integer) —

    Bitfield indicating which optional headers are present



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# File 'lib/cabriolet/models/kwaj_header.rb', line 20

def headers
  @headers
end

#length ⇒ Integer?

Uncompressed length

Returns:

  • (Integer, nil) —

    Length of uncompressed data if present



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# File 'lib/cabriolet/models/kwaj_header.rb', line 24

def length
  @length
end

Instance Method Details

#compression_name ⇒ String

Get human-readable compression type name

Returns:

  • (String) —

    Compression type name



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# File 'lib/cabriolet/models/kwaj_header.rb', line 52

def compression_name
  case @comp_type
  when Constants::KWAJ_COMP_NONE
    "None"
  when Constants::KWAJ_COMP_XOR
    "XOR"
  when Constants::KWAJ_COMP_SZDD
    "SZDD"
  when Constants::KWAJ_COMP_LZH
    "LZH"
  when Constants::KWAJ_COMP_MSZIP
    "MSZIP"
  else
    "Unknown (#{@comp_type})"
  end
end

#has_extra_text? ⇒ Boolean

Check if header has extra text

Returns:

  • (Boolean) —

    true if extra text is present



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# File 'lib/cabriolet/models/kwaj_header.rb', line 93

def has_extra_text?
  @headers.anybits?(Constants::KWAJ_HDR_HASEXTRATEXT)
end

#has_file_extension? ⇒ Boolean

Check if header has file extension

Returns:

  • (Boolean) —

    true if file extension is present



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# File 'lib/cabriolet/models/kwaj_header.rb', line 86

def has_file_extension?
  @headers.anybits?(Constants::KWAJ_HDR_HASFILEEXT)
end

#has_filename? ⇒ Boolean

Check if header has filename

Returns:

  • (Boolean) —

    true if filename is present



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# File 'lib/cabriolet/models/kwaj_header.rb', line 79

def has_filename?
  @headers.anybits?(Constants::KWAJ_HDR_HASFILENAME)
end

#has_length? ⇒ Boolean

Check if header has length field

Returns:

  • (Boolean) —

    true if length is present



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# File 'lib/cabriolet/models/kwaj_header.rb', line 72

def has_length?
  @headers.anybits?(Constants::KWAJ_HDR_HASLENGTH)
end