module TTFunk::Table::Cmap::Format00

def self.encode(charmap)
  next_id = 0
  glyph_indexes = Array.new(256, 0)
  glyph_map = { 0 => 0 }
  new_map =
    charmap.keys.sort.each_with_object({}) do |code, map|
      glyph_map[charmap[code]] ||= next_id += 1
      map[code] = { old: charmap[code], new: glyph_map[charmap[code]] }
      glyph_indexes[code] = glyph_map[charmap[code]]
      map
    end
  # format, length, language, indices
  subtable = [0, 262, 0, *glyph_indexes].pack('nnnC*')
  { charmap: new_map, subtable: subtable, max_glyph_id: next_id + 1 }
end

def [](code)
  @code_map[code] || 0
end

def parse_cmap!
  @language = read(4, 'x2n')
  @code_map = read(256, 'C*')
end

def supported?
  true
end