module Axlsx
  # Conditional Format Rule icon sets
  # Describes an icon set conditional formatting rule.

  # @note The recommended way to manage these rules is via Worksheet#add_conditional_formatting
  # @see Worksheet#add_conditional_formatting
  # @see ConditionalFormattingRule#initialize
  class IconSet

    # instance values that must be serialized as their own elements - e.g. not attributes.
    CHILD_ELEMENTS = [:value_objects]

    # The icon set to display.
    # Allowed values are: 3Arrows, 3ArrowsGray, 3Flags, 3TrafficLights1, 3TrafficLights2, 3Signs, 3Symbols, 3Symbols2, 4Arrows, 4ArrowsGray, 4RedToBlack, 4Rating, 4TrafficLights, 5Arrows, 5ArrowsGray, 5Rating, 5Quarters
    # The default value is 3TrafficLights1
    # @return [String]
    attr_reader :iconSet

    # Indicates whether the thresholds indicate percentile values, instead of number values.
    # The default falue is true
    # @return [Boolean]
    attr_reader :percent

    # If true, reverses the default order of the icons in this icon set.maxLength attribute
    # The default value is false
    # @return [Boolean]
    attr_reader :reverse

    # Indicates whether to show the values of the cells on which this data bar is applied.
    # The default value is true
    # @return [Boolean]
    attr_reader :showValue

    # Creates a new icon set object
    # @option options [String] iconSet
    # @option options [Boolean] reverse
    # @option options [Boolean] percent
    # @option options [Boolean] showValue
    def initialize(options = {})
      @percent = @showValue = true
      @reverse = false
      @iconSet = "3TrafficLights1"
      initialize_value_objects
      options.each do |o|
        self.send("#{o[0]}=", o[1]) if self.respond_to? "#{o[0]}="
      end
      yield self if block_given?
    end

    # @see iconSet
    def iconSet=(v); Axlsx::validate_icon_set(v); @iconSet = v end

    # @see showValue
    def showValue=(v); Axlsx.validate_boolean(v); @showValue = v end

    # @see percent
    def percent=(v); Axlsx.validate_boolean(v); @percent = v end

    # @see reverse
    def reverse=(v); Axlsx.validate_boolean(v); @reverse = v end

    # Serialize this object to an xml string
    # @param [String] str
    # @return [String]
    def to_xml_string(str="")
      str << '<iconSet '
      str << instance_values.map { |key, value| '' << key << '="' << value.to_s << '"' unless CHILD_ELEMENTS.include?(key.to_sym) }.join(' ')
      str << '>'
      @value_objects.each { |cfvo| cfvo.to_xml_string(str) }
      str << '</iconSet>'
    end

    private

    # Initalize the simple typed list of value objects
    # I am keeping this private for now as I am not sure what impact changes to the required two cfvo objects will do.
    def initialize_value_objects
      @value_objects = SimpleTypedList.new Cfvo
      @value_objects.concat [Cfvo.new(:type => :percent, :val => 0), Cfvo.new(:type => :percent, :val => 33), Cfvo.new(:type => :percent, :val => 67)]
      @value_objects.lock
    end
  end
end