Zbig Labacz

controller.php

<?php

require_once 'Db.php';

class apiController
{
    protected $db;

    /**
     * Db
     * @return mixed
     */
    protected function getDb()
    {
        if (isset($db)) {
            $this->db = new Db();
        }

        return $db;
    }

    /**
     * Saves url
     * @param $userToken
     * @param $url
     * @return bool
     * @throws Exception
     *
     */
    public function saveUrl($userToken, $url)
    {
        $result = false;

        if ($this->getDb()->userExists($userToken)) {
            $result = $this->getDb()->addUrl($userToken, $url);
        } else {
            $result = $this->getDb()
                ->createUser($userToken)
                ->addUrl($userToken, $url);
        }

        return $result;
    }

    /**
     * Gets user's urls
     * @param $userToken
     * @return mixed
     * @throws Exception
     */
    public function getUrls($userToken)
    {
        if ($this->getDb()->userExists($userToken)) {
            return $this->getDb()->getUserUrls($userToken);
        } else {
            throw new Exception("Sorry, the user does not exist");
        }
    }

    /**
     * Removes url
     * @param $userToken
     * @param $url
     * @return mixed
     * @throws Exception
     */
    public function removeUrls($userToken, $url)
    {
        if ($this->getDb()->userExists($userToken)) {
            return $this->getDb()->removeUrl($userToken, $url);
        } else {
            throw new Exception("Sorry, the user does not exist");
        }
    }

    /**
     * Users per domain
     * @param $domain
     * @return mixed
     */
    public function getUsersByDomain($domain)
    {
        return $this->getDb()->getUsersByDomain($domain);
    }
}

db.php

<?php

class Db
{
    /**
     * Users
     * @var array
     */
    protected $users;

    /**
     * Domain registry
     * @var array
     */
    protected $domains;

    /**
     * Db constructor.
     */
    public function __construct()
    {
        $this->users = [];
    }

    /**
     * Creates a user
     * @param $token
     */
    public function createUser($token)
    {
        $this->users[$token] = [
            'urls' => []
        ];
    }

    /**
     * Check if user exists
     * @param $token
     * @return bool
     */
    public function userExists($token)
    {
        return isset($this->users[$token]);
    }

    /**
     * Add Url
     * @param $token
     * @param $url
     * @return bool
     * @throws Exception
     */
    public function addUrl($token, $url)
    {
        if (isset($this->users[$token])) {
            $user = & $this->users[$token];
            if (!in_array($url, $user['urls'])) {
                $user['urls'][sha1($url)] = $url;
                $this->buildDomainRegistry($token, $url);

                return true;
            }
            else {
                return false;
            }
        } else {
            throw new Exception("User does not exists");
        }
    }

    /**
     * User Urls
     * @param $userToken
     * @return array
     */
    public function getUserUrls($userToken)
    {
        return array_values($this->users[$userToken]['urls']);
    }

    /**
     * Removes url
     * @param $userToken
     * @param $url
     * @return bool
     */
    public function removeUrl($userToken, $url)
    {
        $user = & $this->users[$userToken];
        $urlSum = sha1($url);

        if (isset($user['urls'][$urlSum])) {
            unset($user['urls'][$urlSum]);

            return true;
        } else {
            return false;
        }
    }

    /**
     * Domain
     * @param $domain
     * @return array
     */
    public function getUsersByDomain($domain)
    {
        if (isset($this->domains[$domain])) {
            return array_values($this->domains[$domain]);
        } else {
            return [];
        }
    }

    /**
     * Get Domain by Url
     * @param $url
     * @return string
     */
    protected function getDomain($url)
    {
        return preg_replace("/^(www\.)?(\w+)\.(\w+)/", "$2.$3", $url);
    }

    /**
     * Build domain registry
     * @param $userToken
     * @param $url
     *
     * @return $this
     */
    protected function buildDomainRegistry($userToken, $url)
    {
        $domain = $this->getDomain($url);

        if (!isset($this->domains[$domain])) {
            $this->domains[$domain] = [];
        }

        if (!isset($this->domains[$domain][$userToken])) {
            $this->domains[$domain][$userToken] = 1;
        } else {
            $this->domains[$domain][$userToken]++;
        }

        return $this;
    }
}