articles_helper.rb

module ArticlesHelper
  def tag_percentage(count)
    total_tags = 0.0

    Article.all_tag_counts.each do |tag|
      total_tags += tag.count
    end

    return tag_percent = (count / total_tags * 100).ceil
  end

  def hex_calculator(percentage, maxr, maxg, maxb, r, g, b)
    red = (r * percentage) + maxr
    green = (g * percentage) + maxg
    blue = (b * percentage) + maxb
    hex = "#%02x%02x%02x" % [red, green, blue]
    return hex
  end

  def tag_popularity_as_hex(count)
    #most saturated colour possible, used for a highly used tag
    max_colour = [255, 0, 0]
    # least saturated colour possible, used for tags that are rarely used
    min_colour = [0, 0, 0]
    # percentage of times the tag has been used
    tag_percent = tag_percentage(count)

    # i = 0 to 3 for spaces in array, correlates to R, G & B.
    for i in 0..2
      # we find the distance between each value, i.e. between 100% and 1%
      range = min_colour[i] - max_colour[i]
      # then find 1% of the range
    end

    one_red = range[0] / 100
    one_green = range[1] / 100
    one_blue = range[2] / 100

    # we then multiply the one percent of the range by the tag percentage and add the original value back in
    hex = hex_calculator(tag_percent, max_colour[0], max_colour[1], max_colour[2], one_red, one_green, one_blue)
  end
end