Find all values between curly braces in a string and match and replace based on case statement.

string_lookup.rb

# includes Replacer
# 
# replace :text
# 
# Lookup.new("I am a string with {help_link}, replace me.").perform
# Returns => "I am a string with https://google.com, replace me."
module Replacer
  
  def replace(text)
    Lookup.new(text).perform
  end

  class Lookup
    def initialize(body)
      @body = body
    end

    def perform
      find_anchors_and_replace
    end
    
    private

    attr_accessor :body

    def find_anchors_and_replace
      body.gsub(/\{.*?\}/, mappings)
    end

    def mappings
      matches = {}
      body.scan(/\{.*?\}/) { |x| matches[x] = lookup_case(x) }

      return matches
    end

    def lookup_case(anchor)
      case anchor
      when "{help_link}"
        # Do lookup here
        return "https://google.com"
      else
        ""
      end
    end
  end
end