require 'trollop'
require 'rest-client'

# This class parses commandline arguments
module GrepPage
  class Parser
    def initialize(args)
      parser = Trollop::Parser.new do
        opt :search,
          "text to search",
          :type => :string,
          :required => false,
          :short => "-s"
        banner <<-EOS

Usage:
  grepg user_name topic_name [-s search_term]

Examples:
  grepg kdavis css
  greppg kdavis css -s color
        EOS
      end

      @opts = Trollop::with_standard_exception_handling parser do
        raise Trollop::HelpNeeded if args.size < 2 # show help screen
        parser.parse args
      end

      leftovers = parser.leftovers
      @user = leftovers.shift
      @topic = leftovers.shift
      @search_term = @opts[:search]
    end

    def get_all_topics(user)
      GrepPage::API.sheets(user)
    end

    def filter_topics(topics, topic_name = '')
      sheet = topics.find{|topic| topic[:name].downcase == topic_name.downcase}
      sheet = topics.find{|topic| topic[:name].downcase[topic_name.downcase]} unless sheet
      sheet
    end

    def get_cheats(user, sheet_id)
      GrepPage::API.cheats(user, sheet_id)
    end

    def filter_cheats(cheats, search_term)
      cheats.select do |cheat|
        (cheat[:description].downcase[search_term.downcase] ||
         cheat[:command].downcase[search_term.downcase]) != nil
      end
    end

    def run!
      headers = ["User: #{@user}", "Topic: #{@topic}"]
      headers << "Search-Term: #{@search_term}" if @search_term
      puts headers.join(", ")

      begin
        topics = get_all_topics(@user)
      rescue RestClient::ResourceNotFound
        puts "That username does not exist"
        exit 1
      end

      topic = filter_topics(topics, @topic)
      if topic.nil? || topic.empty?
        puts "Can't find that topic. Choose one of the following"
        puts topics.map{|t| t[:name]}
        exit 1
      end

      cheats = get_cheats(@user, topic[:id])
      cheats = filter_cheats(cheats, @search_term) if @search_term

      GrepPage::Formatter.cheat_rows(cheats, @search_term)
    end
  end
end