require_relative "one_bus_away/version"
require 'rest-client'
require 'utilities'
require 'contracts'

class OneBusAway
  include Contracts::Core
  C = Contracts

  Contract String => String
  def initialize(api_key)
    @api_key = api_key
  end

  Contract String
  def current_time
    response = RestClient.get("http://api.pugetsound.onebusaway.org/api/where/current-time.json?key=#{@api_key}")
    json = JSON.parse(response)
    time = json["data"]["entry"]["time"]
    return time.to_s
  end

  # Contract C::Num, C::Or[C::Num, String], C::Num => C::ArrayOf[C::Any]
  def arrivals_and_departures_for_stop(stop, route, time_to_look_for)
    if valid_stop?(stop) && valid_route?(route)
      response = RestClient.get("http://api.pugetsound.onebusaway.org/api/where/arrivals-and-departures-for-stop/1_#{stop}.json?key=#{@api_key}&minutesAfter=#{time_to_look_for}")
      json = JSON.parse(response)
      arrivalsAndDepartures = json["data"]["entry"]["arrivalsAndDepartures"]

      outputs = []

      arrivalsAndDepartures.each do |bus|
        if bus["routeShortName"] == route
          outputs.sort
          outputs.push(Utilities.convert_time(bus["scheduledDepartureTime"].to_s))
        end
      end

    return outputs
    else
      fail "Either your route or stop is invalid."
    end


  end
  
  # Contract C::Num => C::Bool
  def valid_stop?(stop_number)
    response = RestClient.get("http://api.pugetsound.onebusaway.org/api/where/stop-ids-for-agency/1.json?key=#{@api_key}")
    json = JSON.parse(response)
    
    if json["code"] == 200
      json["data"]["list"].include? "1_#{stop_number}"
    else
      fail "OneBusAway API HTTP response error #{json['code']}"
    end
  end

  # Contract C::Or[C::Num, String] => C::Bool
  def valid_route?(route_name)
    response = RestClient.get("http://api.pugetsound.onebusaway.org/api/where/routes-for-agency/1.json?key=#{@api_key}")
    json = JSON.parse(response)
    
    if json["code"] == 200
      array = []
      json["data"]["list"].map { |x| array.push x["shortName"] }
      
      array.include? route_name.to_s
    else
      fail "OneBusAway API HTTP response error #{json['code']}"
    end
  end

end