require 'set'
class Grammardef
    def initialize
        @rules = Hash.new()
    end

    def setexiom(axiom)
        @axiom = axiom
        #print "axiom:\n", @axiom, "\n", "setted\n"
    end
    def setnterm(nterms)
        @nterms = nterms.split(/ +/).delete_if {|x| x == ""}
        #print "nterms:\n", @nterms, "\n", "setted\n"
    end

    def setterm(terms)
        @terms = terms.split(/ +|\"/).delete_if {|x| x == ""}
        #print "terms:\n", @terms, "\n", "setted\n"
    end

    def setrules(rules)
        #print "rules:\n", rules.split(/( *|\\n)\$RULE /).delete_if {|x| (x == "") || (x == "\\n")}, "\n", "setted\n"
        rulesregexp = Regexp.new(/\$RULE (([A-Z]\'{0,1}) =(([( [A-Z]\'{0,1})( \"[a-z]\"| \"\*\"| \"\+\"| \"\(\"| \"\)\")]+\\n| \$EPS\\n)+))/)
        a = rulesregexp.match(rules)[0]
        #print "rules:\n", a, "\n"
        self.setrule(a)

        while rulesregexp.match(rules) != nil
            rules = rules[rulesregexp.match(rules)[0].length, rules.length]
            if (rulesregexp.match(rules) != nil) 
                a = rulesregexp.match(rules)[0]
                #print a, "\n"
                self.setrule(a)
            end
        end
        #print "rules hash:\n", @rules, "\n"
    end

    def setrule(rule)
        ruleregexp = Regexp.new(/\$RULE (([A-Z]\'{0,1}) =(([( [A-Z]\'{0,1})( \"[a-z]\"| \"\*\"| \"\+\"| \"\(\"| \"\)\")]+\\n| \$EPS\\n)+))/)
        leftpart = ruleregexp.match(rule)[2]
        rightparts = ruleregexp.match(rule)[3]
        #print "rule left:\n", leftpart, "\nrule rights:\n", rightparts, "\n"
        rightpartsarr = rightparts.split(/\\n/).delete_if {|x| x == ""}
        #print "right parts array\n", rightpartsarr, "\n******************************************************\n"
        rightpartsset = Set.new()
        (rightpartsarr).each do |x|
            onealt = x.split(/ +|\"/).delete_if {|x| x == ""}
            rightpartsset.add(onealt)
            #print onealt, "\n******************************************************\n"
            @rules[leftpart] = rightpartsset
        end
    end

    def axiom
        @axiom
    end

    def nterms
        @nterms
    end

    def terms
        @terms
    end

    def rules
        @rules
    end

    def rulebynterm(nterm)
        @rules[nterm]
    end

end

class Progreader
    def initialize(exampleprog)
        #exampleprog = "$AXIOM E\\n$NTERM E' T T' F\\n$TERM \"+\" \"*\" \"(\" \")\" \"n\"\\n$RULE E =  T\\n$RULE E' = \"+\" T E'\\n $EPS\\n"

        progregexp = Regexp.new(/\$AXIOM ([A-Z]\'{0,1})\\n\$NTERM(( [A-Z]\'{0,1})+)\\n\$TERM(( "[a-z\*\+\(\)]")+)\\n((\$RULE (([A-Z]\'{0,1}) =(([( [A-Z]\'{0,1})( \"[a-z]\"| \"\*\"| \"\+\"| \"\(\"| \"\)\")]+\\n| \$EPS\\n)+)))+)/)
        prog = progregexp.match(exampleprog)

        @arifmGrammar = Grammardef.new

        #print "allprogram:\n", prog[0], "\n"
        #print "axiom:\n", prog[1], "\n"
        @arifmGrammar.setexiom(prog[1])

        #print "nterm:\n", prog[2], "\n"
        @arifmGrammar.setnterm(prog[2])

        #print "term:\n", prog[4], "\n"
        @arifmGrammar.setterm(prog[4])

        #print "rules:\n", prog[6], "\n"
        @arifmGrammar.setrules(prog[6])
    end

    def arifmGrammar
        @arifmGrammar
    end
end

class Filecustomreader
    def initialize(filename)
        #read from file
        file = File.new(filename, "r")
        @mygram = "";
        while line = file.gets
            @mygram += line.chomp + "\n"
        end
        #print mygram
        #print "\nqqqqq\n"
    end

    def mygram
        @mygram
    end

end

exampleprog = "$AXIOM E\\n$NTERM E' T T' F\\n$TERM \"+\" \"*\" \"(\" \")\" \"n\"\\n$RULE E =  T\\n$RULE E' = \"+\" T E'\\n $EPS\\n$RULE T = F T'\\n$RULE T' = \"*\" F T'\\n $EPS\\n$RULE F = \"n\"\\n \"(\" E \")\"\\n"
progreader = Progreader.new(exampleprog)
arifmGrammar = progreader.arifmGrammar
#print arifmGrammar, "\n"