class MiniXml

# File lib/mini_xml.rb, line 7
def self.generate(&block)
  out = []
  MiniXml.new(out).instance_eval(&block)
  out.join("")
end

# File lib/mini_xml.rb, line 3
def initialize(out)
  @out = out
end

# File lib/mini_xml.rb, line 13
def self.xml_from_data(data = {}, fields = [])
  out = []
  xml_attributes = {}
  xml_attributes[:version] = (data[:xml_version] || '1.0')
  xml_attributes[:encoding] = (data[:encoding] || 'UTF-8')
  rss_version = data[:rss_version] || '2.0'
  title_str = data[:title] || 'RSS'
  description_str = data[:description] || ''
  link_str = data[:link] || ''
  generate do
    xml(xml_attributes)
    rss(version: rss_version) do
      channel do
        title {title_str}
        description {description_str}
        link {link_str}
        data[:data].each do |da|
          item do
            if da.is_a?(Hash)
              da.each do |k, v|
                next if fields.size > 0 && !fields.include?(k)
                p = proc {v}
                send(k, &p)
              end
            else
              raise 'fields argument can\'t empty!' if fields.empty?
              fields.each do |m|
                p = proc {da.send(m)}
                puts da.title
                send(m.to_s, &p)
              end
            end
            nil
          end
        end
        nil
      end
    end
  end
end

# File lib/mini_xml.rb, line 54
def comment(content)
  @out << "<!-- #{content} -->"
  nil
end

# File lib/mini_xml.rb, line 64
def generate_attributes(attributes_hash = {})
  attributes_str = ""
  attributes_hash.each {|key, val| attributes_str << " #{key}=\"#{val}\" "}
  attributes_str.rstrip
end

# File lib/mini_xml.rb, line 70
def method_missing(tagname, attributes = {})
  @out << "<#{tagname}"
  @out << generate_attributes(attributes)
  @out << ">"
  if block_given?
    content = yield
    @out << content.to_s if content
    @out << "</#{tagname}>"
  end
  nil
end

# File lib/mini_xml.rb, line 59
def xml(tagname, attributes = {version: '1.0', encoding: 'UTF-8'})
  @out << "<?xml#{generate_attributes(attributes)}?>"
  nil
end