#!/usr/bin/ruby -Ku
require 'bindata'

class Brainfuck
    def self.read_file file
        if not File.exist? file
            puts "File " + file + " doesn't exist!"
            exit 1
        end
        @new_name = file.gsub(/.bf/,'')
        @@code = File.open(file).readlines.map { |line| line.chomp }.join.split('')
    end

    def self.validate
        @a = 0
        @@code.each do |item|
            if item == '['
                @a += 1
            end
            if item == ']'
                @a -= 1
            end
        end
        if @a > 0
            puts "Unexpected [ or ]"
            exit 1
        end
    end

    def self.compile
        $cells = Array.new
        $cell  = 0
        @fun = Proc.new do |command,file|
            if $cells[$cell].nil?
                    $cells[$cell] = 0
            end

            case command
            when '+'
                BinData::Int8be.new(0x1).write(file)
                $cells[$cell] += 1
            when '-'
                BinData::Int8be.new(0x2).write(file)
                $cells[$cell] -= 1
            when '>'
                BinData::Int8be.new(0x3).write(file)
                $cell += 1
            when '<'
                BinData::Int8be.new(0x4).write(file)
                $cell -= 1
            when ','
                BinData::Int8be.new(0x5).write(file)
            when '.'
                BinData::Int8be.new(0x6).write(file)
            end
        end

        brackets = 0
        loop_code = Array.new
        File.open(@new_name,'wb') do |file|
            @@code.each_with_index do |item,index|
                if $cells[$cell].nil?
                    $cells[$cell] = 0
                end

                if item == '['
                    brackets += 1
                    next
                end

                if brackets > 0 and item != ']'
                    loop_code << item
                    next
                end


                if item == ']'
                    brackets -= 1
                    while $cells[$cell] != 0
                        loop_code.each do |c|
                            @fun.call c,file
                            break if $cells[$cell] == 0
                        end
                    end
                    next
                end
                @fun.call item,file
            end
        end
    end
end

ARGV.each do |file_name|
    if not File.exist? file_name
        puts "File #{file_name} doesn't exist!"
        exit 1
    end
    Brainfuck.read_file file_name
    Brainfuck.validate
    Brainfuck.compile
end