<?php
  
  namespace FootyRoom\Queries\Poll;
  
  use MongoDB\BSON\ObjectId;
  use FootyRoom\Support\MongoClient;
  use FootyRoom\Support\AutoMapper;
  use FootyRoom\Queries\VoteQuery;
  
  class PollQueryHandler
  {
      /**
       * @var \FootyRoom\Support\MongoClient
       */
      protected $mongo;
  
      /**
       * Constructor.
       *
       * @param \FootyRoom\Support\MongoClient $mongo
       */
      public function __construct(MongoClient $mongo, VoteQuery $voteQuery)
      {
          $this->mongo = $mongo->footyroom;
          $this->voteQuery = $voteQuery;
      }
  
      /**
       * Query handler.
       *
       * @param \FootyRoom\Queries\Poll\PollQuery $query
       *
       * @return \FootyRoom\Queries\Poll\Poll|null
       */
      public function handle(PollQuery $query)
      {
          $queryParams = [
              '_id' => new ObjectId($query->getPollId()),
          ];
  
          $pollDto = $this->mongo->polls->findOne($queryParams, []);
  
          $poll = AutoMapper::map($pollDto, Poll::class);
  
          $poll->id = (string) $pollDto->_id;
  
          /**
           * Get poll results.
           */
          $aggregate = $this->voteQuery->aggregate('poll-'.$query->getPollId());
  
          $poll->totalVotes = $aggregate->totalVotes ?? 0;
          $poll->maxVotes = $aggregate->maxVotes ?? 0;
  
          $votesByChoiceId = [];
  
          if (isset($aggregate->votes)) {
              foreach ($aggregate->votes as $vote) {
                  if (isset($vote->value)) {
                      $votesByChoiceId[$vote->value] = $vote->votes;
                  }
              }
          }
  
          foreach ($poll->choices as $choice) {
              $choice->votes = isset($votesByChoiceId[$choice->id]) ? $votesByChoiceId[$choice->id] : 0;
          }
  
          return $poll;
      }
  }