<?php

namespace App\Service;

use App\Entity\Hub;
use App\Entity\Rider;

use Doctrine\ORM\EntityManagerInterface;

class HubCounter
{
    const RIDER_COUNT_KEY           = 'hub.rider';
    const JOB_ORDER_KEY             = 'hub.jo';

    protected $em;
    protected $redis;

    public function __construct(EntityManagerInterface $em)
    {
        $this->em = $em;

        // TODO: make it read redis settings from config
        //       build a service maybe?
        $this->redis = new Predis\Client();
    }

    // get rider key based on id
    protected function getRiderKey($hub_id)
    {
        return self::RIDER_COUNT_KEY . '.' . $hub_id;
    }

    // get job order key based on id
    protected function getJobOrderKey($hub_id)
    {
        return self::JOB_ORDER_KEY . '.' . $hub_id;
    }

    // get riders available
    public function getAvailableRiderCount($hub_id)
    {
        $key = $this->getRiderKey($hub_id);
        $value = $this->redis->get($key);
        if ($value != null)
            return $value;

        // not in cache
        $hub = $em->getRepository(Hub::class)->find($hub_id);
        $riders = $hub->getActiveRiders();
        $rider_count = count($riders);

        // store in cache
        $this->redis->setnx($key, $rider_count);
        return $rider_count;
    }

    // get job order queue
    public function getUnfinishedJobOrderCount($hub_id)
    {
        $key = $this->getRiderKey($hub_id);
        $value = $this->redis->get($key);
        if ($value != null)
            return $value;

        // not in cache
        $hub = $em->getRepository(Hub::class)->find($hub_id);
        $riders = $hub->getActiveRiders();
        $rider_count = count($riders);

        // store in cache
        $this->redis->setnx($key, $rider_count);
        return $rider_count;
    }

    // add rider available
    public function addAvailableRider($hub_id, $count = 1)
    {
        // cache
        $this->getAvailableRiderCount($hub_id);

        $key = $this->getRiderKey($hub_id);
        $this->redis->incrby($key, $count);
    }

    // decrease rider available
    public function decAvailableRider($hub_id, $count = 1)
    {
        // cache
        $this->getAvailableRiderCount($hub_id);

        $key = $this->getRiderKey($hub_id);
        $this->redis->decrby($key, $count);
    }

    // add job order queue
    public function addUnfinishedJobOrder($hub_id, $count = 1)
    {
        // cache
        $this->getUnfinishedJobOrderCount($hub_id);

        $key = $this->getJobOrderKey($hub_id);
        $this->redis->incrby($key, $count);
    }

    // decrease job order queue
    public function decUnfinishedJobOrder($hub_id, $count = 1)
    {
        // cache
        $this->getUnfinishedJobOrderCount($hub_id);

        $key = $this->getJobOrderKey($hub_id);
        $this->redis->decrby($key, $count);
    }
}