laurentzziu/hash2lrtemplate

# frozen_string_literal: true

module Hash2lrtemplate
  # Transformations:
  #
  # - Transform +"keys"+ to +keys+ (remove quotes)
  # - Transform +[]+ to +{}+
  # - Transform +:+ to +=+
  # - Remove leading and ending +{}+
  # - +,+ before closing +}+
  class JSON2lrtemplate
    include CallableClass

    attr_reader :json_string

    def initialize(json_string)
      raise Hash2lrtemplate::Error, 'Invalid class. Expected class: `String`' unless json_string.is_a?(String)

      @json_string = json_string
    end

    #
    # Convert from JSON to +.lrtemplate+ format
    #
    # @return [String] Converted string
    #
    def call
      convert
    end

    private

    def convert
      @json_string.gsub(/"(\w+)"(?=:)/) { |_| $1.camelize(false) }
                  .gsub(/(\[[.\S\s^"]*?\])/) { |_| $1.tr('[]', '{}') }
                  .gsub(':', ' = ')
                  .sub(/\A{/, '').sub(/}\Z/, '')
                  .gsub(/(?<=.)(}){1}(?=.)?/) { |_| ",#{$1}" }
    end
  end
end