Simple sass grid generator script

scss_grid_generator.rb

#!/usr/bin/env ruby

# calculate the columns width in percentage
def calc_cols(num)
    cols = Array.new(num)

    for i in 0...num do
        # 100% (total) / total number of columns
        # * the number of columns we are current calculating
        cols[i] = (100.0 / num * (i + 1)).round 5
    end

    return cols
end

# write to the file the final grid
def create_grid(filename, cols_w, cols_fix, cols_bound)
    # open up file with write privileges
    file = File.new(filename, 'w')

    # basic scss for grid to work
    file.puts <<-SCSS
.row {
\t&::before,
\t&::after {
\t\tdisplay: table;
\t\tcontent: " ";
}

\t&::after {
\t\tclear: both;
\t}
}
SCSS

    file.puts

    file.puts <<-SCSS
[class*="col-"] {
\tdisplay: inline-block;
\twidth: 100%;
\tfloat: left;
\tmin-height: 1px;
}
SCSS

    # this only inserts a new line in the file
    file.puts

    # for all columns prefixes we have, create 1 media query
    for i in 0...cols_fix.length
        file.puts '@media screen and (min-width: %s) {' % [cols_bound[i]]
        
        # inside each media query, we have the actual columns classes, for all
        # columns width
        for j in 0...cols_w.length
            file.puts "\t.col-%s-%d {" % [cols_fix[i], j + 1]
            file.puts "\t\twidth: %s%%;" % [cols_w[j]]
            file.puts "\t}"
        end

        file.puts '}'
        file.puts
    end

    file.close
end

def main
    print 'Type the number of columns in your grid: '
    col_num = gets.to_i

    puts 'Calculating columns width...', ''
    cols = calc_cols col_num

    print 'Type the columns infix (for responsiveness): '
    cols_fix = gets.split ','

    # get rid of white space
    for i in 0...cols_fix.length do
        cols_fix[i] = cols_fix[i].strip
    end

    cols_bound = Array.new()

    cols_fix.each do |e|
        print 'Min-width for %s: ' % [e]
        cols_bound.push gets.chomp
    end
    puts

    create_grid '_grid.scss', cols, cols_fix, cols_bound
end

if __FILE__ == $0
    main
end