[RUBY] Get all available characters in a .WOFF font

get-available-chars.rb

#!/usr/bin/env ruby
require 'optparse'

# Get available characters
#
# Written by Phoenix Enero.
#
# It requires:
#	- `woff2sfnt` command-line tool. It can be installed through
#	  `apt-get install woff-tools` in Ubuntu/Debian.
#	- `ttfunk` Ruby gem. Include this in your `Gemfile`
#
# It works by:
#	- Converting the WOFF files into a temporary OTF file
#	- Accessing the `cmap` table and getting the unicode values
#
# The values get outputted to a file with the same name as the input file that
# generated it. For example, inputting "charter-regular.woff" will output
# "charter-regular.unc"
#
# You can also choose the file extension. By default it is `.unc`



## Lets start!

temp_name = "__#{Time.now.to_i.to_s}.font"


# Option handling

options = {:extension => '.unc', :file => ''}
OptionParser.new do |o|
	o.banner = "Usage: get-available-chars.rb [options]"

	o.on("-f", "--font [FONT]",
		  "The source font. Must be in WOFF format (NOT WOFF2)") do |font|
		options[:file] = font
	end

	o.on("-x", "--extension [EXTENSION]",
		  "The extension for the output file(s).") do |ext|
		options[:extension] = ext || '.unc'

		# Ensure extension begins with dot `.`
		options[:extension].sub!(/\A\.?(?=.)/, ".")
	end
end.parse!

# Error handling
at_exit do
	if $! # If the program exits due to an exception
		# delete temp font if it exists
		if File.file?( temp_name )
			File.delete( temp_name )
		end

		puts 'Exiting'
	end
end


# Check if font file exists
if ! File.file?( options[:file] )
	puts 'Font does not exist'
	exit
end


#######################################
# Convert WOFF to OTF/TTF
#######################################

`woff2sfnt "#{options[:file]}" > #{temp_name}`

if ! File.file?( temp_name )
	raise 'Failed to generate temporary font'
	exit
end





#######################################
# Get available characters
#######################################

require 'ttfunk'

file = TTFunk::File.open( temp_name )
puts "Font name: #{file.name.font_name.join(', ')}"

characters = file.cmap.unicode.first.code_map.keys

# Remove `temp` font
File.delete( temp_name )




#######################################
# Output to file
#######################################
basename = File.basename( options[:file], File.extname( options[:file] ) )

output = File.open( basename + options[:extension],"w" );

# Output characters as a hexadecimal comma-delimited list
output << characters.map{|character| character.to_s(16)}.join(",")

output.close

# And we're done!!!

glob-get-available-chars.rb

#!/usr/bin/env ruby
require 'optparse'

# A wrapper of the get-available-chars.rb script for multiple files.

# Option handling

options = {:extension => '.unc', :pattern => '*.woff'}
OptionParser.new do |o|
	o.banner = "Usage: get-available-chars.rb [options]"

	o.on("-p", "--pattern [PATTERN]", "The pattern used") do |pattern|
		options[:pattern] = pattern
	end

	o.on("-x", "--extension [EXTENSION]", "The extension for the output file(s).") do |ext|
		options[:extension] = ext || '.unc'

		# Ensure extension begins with dot `.`
		options[:extension].sub!(/\A\.?(?=.)/, ".")
	end
end.parse!

files = Dir.glob( options[:pattern] )

files.each do |file|
	system( "ruby get-available-chars.rb -f \"#{file}\" -x \"#{options[:extension]}\"" )
end