gnux_merge_directories_as_pdf.rb

#!/usr/bin/env ruby
# vim: set ts=2 sw=2 et:

require 'find'
require 'colorize'
require 'fileutils'

class Merger
    def initialize
        @ind = 0
    end
    
    def merge_pdfs where
        pdf_basename = File.basename(File.expand_path(where))
        pdf_path = File.join(File.dirname(where), pdf_basename + '.pdf')
        outpdf_path = output_of pdf_path
        outpdf_dir = File.dirname(outpdf_path)
        FileUtils.mkdir_p outpdf_dir
        FileUtils.mkdir_p (output_of where)
        
        sub_pdfs = []
        Dir.chdir(where) do 
            sub_pdfs.concat Dir['*.pdf']
        end
        Dir.chdir(output_of where) do 
            sub_pdfs.concat Dir['*.pdf']
        end
        sub_pdfs.sort!
        
        puts "#{indent} #{where.yellow} merge PDF"
        sub_pdfs.each do |file|
            puts "#{indent} #{where.yellow}   src = %s" % file 
        end
        if sub_pdfs.size == 0 then
            puts "#{indent} #{where.yellow}" + " no PDF found in subtree !".red + " skipping merge."
        else
            pdfs = sub_pdfs.map do |file|
                if File.exist? File.join(where, file) then File.join(where, file)
                else File.join(output_of(where), file)
                end
            end
            puts "#{indent} #{pdf_path.green} merged"
            system "pdftk", *pdfs, "cat", "output", outpdf_path
        end
        sub_pdfs = Dir["#{output_of File.dirname(where)}/*.pdf"].sort
    end
    
    def recurse where
        puts "#{indent} #{where.yellow} begin recursing_dir"
        indent_more
        Find.find(where) do |path|
            next unless FileTest.directory?(path)
            next if File.basename(path) == "_build"
            next if path == where
            next if path == "."
            recurse path
            Find.prune
        end
        indent_less
        puts "#{indent} #{where.yellow} end recursing_dir"
        puts "#{indent} #{where.yellow} begin merging_pdfs"
        merge_pdfs where
        puts "#{indent} #{where.yellow} end merging_pdfs"
    end
    
    def run where
        FileUtils.rm_rf "_build"
        recurse where
    end
    
    private
    
    def output_of where
        File.join('_build', where)
    end
    
    def indent
        ("  " * @ind)
    end
    def indent_more
        @ind += 1
    end
    
    def indent_less
        @ind -= 1
    end
    
end

app = Merger.new
if ARGV.size > 0 and File.directory? ARGV[0] then
    app.run ARGV[0]
else
    puts "Usage: #{$0} directory"
end