#!/usr/bin/env ruby
args = ARGV.reverse
paranoia = true
f_tags = "./lst"

def usage()
    puts "
usage:
    #{__FILE__} [-x] [filename]
        -x: don't use cdparanoia
        filename: the file where to find the tags
        
        the tag file must be formated in order to contain a soundfile group of tags per line as this:
            <tag>: <data>
        the accepted tags are: artist, album, year, comment and genre,
        plus the title number for the title infos.
            e.g.:
                artist: roger
                album: the musette big back
                1: acordeon hardcore
                2: psychimamie

                etc."
    exit
end

class F_tags

    attr_reader :infos

    def initialize(filename)
        begin
            f_tags = File.open(filename)
        rescue
            puts "error while opening the tag file:"
            puts $!
            exit
        end

        titles = []
        artist = album = year = comment = genre = "unknown"
        title_count = 0
        while (line = f_tags.gets)
            puts line.inspect # debug
            if not line[/^ *$/]
                case line[/^\w+: /]
                    when "artist: ", "artiste: " then artist = $'.chomp
                    when "album: " then album = $'.chomp
                    when "year: ", "année: " then year = $'.chomp
                    when "comment: ", "commentaire: " then comment = $'.chomp
                    when "genre: " then genre = $'.chomp
                else
                    tag, data = $&, $'
                    if tag[/^\d+/]
                        titles << data
                        title_count += 1
                    else
                        puts "invalid tag: #{tag}"
                        exit
                    end
                end
            end
        end
        f_tags.close
        @infos = {  "artist"    => artist,
                    "album"     => album,
                    "year"      => year,
                    "comment"   => comment,
                    "genre"     => genre,
                    "count"     => title_count,
                    "titles"    => titles
        }
    end
end

while args != []
    argument = args[args.length - 1]
    case argument
        when "-x" then paranoia = false
        else File.exist?(argument) ? f_tags = argument : usage
    end
    args.pop
end

tags = F_tags.new(f_tags)

%x(cdparanoia -B) if paranoia
fichiers = Dir.new('.').entries.delete_if { |f| ! f[/\.wav/] }

if fichiers.length != tags.infos['count'] and tags.infos['count'] != 0
    puts "error: the number of extracted titles and the one get from the tagsfile do not match"
    exit
end


fichiers.each { |fichier|
    numero = fichier[/\d{2}/]

    opt_title = ""
    opt_title << "-t #{tags.infos['titles'][numero.to_i-1] }" if tags.infos['count'] != 0 
    puts %Q*%x(oggenc -q8 -N #{numero} -a "#{tags.infos['artist']}" -G "#{tags.infos['genre']}" -d "#{tags.infos['year']}" -l "#{tags.infos['album']}" -c "#{tags.infos['comment']}" "#{opt_title}" -o #{numero}.ogg #{fichier})* # debug

    %x(oggenc -q8 -N #{numero} -a "#{tags.infos['artist']}" -G "#{tags.infos['genre']}" -d "#{tags.infos['year']}" -l "#{tags.infos['album']}" -c "#{tags.infos['comment']}" "#{opt_title}" -o #{numero}.ogg #{fichier})
}