module HexaPDF

def self.data_dir
  unless defined?(@data_dir)
    require 'rbconfig'
    @data_dir = File.expand_path(File.join(__dir__, '..', '..', 'data', 'hexapdf'))
    unless File.directory?(@data_dir)
      @data_dir = File.expand_path(File.join(RbConfig::CONFIG["datadir"], "hexapdf"))
    end
    unless File.directory?(@data_dir)
      raise "HexaPDF data directory not found! This is a bug, please report it!"
    end
  end
  @data_dir
end

def self.font_on_invalid_glyph(codepoint, invalid_glyph)
  font_wrapper = invalid_glyph.font_wrapper
  document = font_wrapper.pdf_object.document
  variant = case
            when font_wrapper.italic? && font_wrapper.bold? then :bold_italic
            when font_wrapper.bold? then :bold
            when font_wrapper.italic? then :italic
            else :none
            end
  document.config['font.fallback'].each do |font_name|
    font = document.fonts.add(font_name, variant: variant) rescue document.fonts.add(font_name)
    glyph = font.decode_codepoint(codepoint)
    unless glyph.kind_of?(HexaPDF::Font::InvalidGlyph)
      return [glyph]
    end
  end
  [invalid_glyph]
end