require 'nokogiri'
require 'term/ansicolor'

class SmartXmlLogger

  include Term::ANSIColor

  def initialize(forward_to, method = nil)
    @logger = forward_to
    @method = method
  end

  def configure(key, options)
    @configuration ||= {}
    @configuration[key] = options
  end

  def log(text)
    return unless @logger
    @logger.send(@method, text)
  end

  def log_xml(key, xml)
    return unless @logger

    options = @configuration[key]

    dom = Nokogiri::XML::Document.parse(xml)

    node_set = options[:xpath] ? dom.xpath(options[:xpath]) : dom

    self.log(if node_set.respond_to?(:each)
      node_set.map{|node| self.print_node(node, options[:start_indent] || 0)}.join
    else
      self.print_node(node_set, options[:start_indent] || 0)
    end)
  end

  #private

  def print_node(node, indent = 0)
    return '' if node.text?

    empty = node.children.empty?
    has_text = node.children.detect{|child| child.text?}

    out = ' ' * indent

    attrs = node.attributes.values.map{|attr| %|#{attr.name}="#{red(attr.value)}"|}.join(' ')
    attrs = " #{attrs}" if attrs.present?

    out << "<#{green(node.name)}#{attrs}#{'/' if empty}>"

    if has_text
      out << "#{red(node.text)}"
    else
      out << "\n"
    end

    node.children.each do |child|
      out << self.print_node(child, indent + 2)
    end

    out << ' ' * indent unless has_text || empty
    out << "</#{green(node.name)}>\n" unless empty
    out
  end

end