# RSS to HTML converter
# Copyright (C) 2015  Harald Eilertsen
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
#   (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

require 'rss'
require 'open-uri'
require 'erb'

module Rss2Html
  class Feed
    attr_reader :title, :url

    def initialize(args)
      @title = args.delete('title')
      @url = args.delete('url')

      @feed_header = load_template('feed_header.html.erb')
      @feed_footer = load_template('feed_footer.html.erb')
      @item_template = load_template('item.html.erb')
    end

    def fetch
      open(url) do |rss|
        feed = RSS::Parser.parse(rss)

        feed.entries.each do |item|
          yield item
        end
      end
    end

    def render
      feed = self
      output = @feed_header.result(binding)

      fetch do |entry|
        item = FeedItem.new(entry)
        output += @item_template.result(binding)
      end

      output += @feed_footer.result(binding)
    end

    private

    def load_template(t)
      view_path = File.join(File.dirname(__FILE__), 'views')
      ERB.new(IO.read(File.join(view_path, t)))
    end
  end
end