<?php

$testConnection = DB::openConnection('default', 'localhost', 'root', '1234', 'testdb');

$test = new TestClass();
echo $test->sayHello() . PHP_EOL;

$addRowTest = new AddRowTest();

$addRowTest->addRow('test', array(
    'login' => 'rav',
    'data'  => "some sor't of data",
));

var_dump($addRowTest->getRow());



class AddRowTest
{
    private function createTable()
    {
        DB::getConnection()->query("CREATE TABLE IF NOT EXISTS `test` (`login` VARCHAR(255), `data` TEXT) ENGINE=InnoDB");
    }

    public function addRow($tableName, $values = array())
    {
        $this->createTable();

        DB::getConnection()->addRow($tableName, $values);
    }

    public function getRow()
    {
        $stmt = DB::getConnection()->prepare("SELECT * FROM `test` WHERE `login`=?");

        $login = 'rav';
        $stmt->bind_param('s', $login);

        if ($stmt->execute()) {
            $res = $stmt->get_result();

            return $res->fetch_assoc();
        }

        return false;
    }
}

class TestClass
{
    public function sayHello()
    {
        $res = DB::getConnection()->query("SELECT 'hello'");

        return array_shift($res->fetch_row());
    }
}

class DB extends mysqli
{
    private static $_connections = array();

    private function __construct($host, $user, $password, $dbname, $port, $socket) {
        parent::__construct($host, $user, $password, $dbname, $port, $socket);
    }

    public static function openConnection($connectionName, $host, $user, $password = '', $dbname = '', $port = 3306, $socket = null)
    {
        if (empty($connectionName)) {
            $connectionName = 'default';
        }
        if (self::connectionExist($connectionName)) {
            return self::$_connections[$connectionName];
        }
        $connection = new DB($host, $user, $password, $dbname, $port, $socket);

        if (mysqli_connect_error()) {
            throw new DBException(sprintf("Failed to open mysqli connection [%s:%s]", mysqli_connect_errno(), mysqli_connect_error()));
        }

        self::$_connections[$connectionName] = $connection;

        return $connection;
    }

    public static function getConnection($connectionName = 'default')
    {
        if (self::connectionExist($connectionName)) {
            return self::$_connections[$connectionName];
        }

        throw new DBException(sprintf("Cant find opened connection named %s", $connectionName));

    }

    private static function connectionExist($connectionName)
    {
        if (isset(self::$_connections[$connectionName]) && self::$_connections[$connectionName] instanceof mysqli) {
            return true;
        } else {
            return false;
        }
    }

    public function addRow($tableName, $values, $replace = false)
    {
        $fields      = array();
        $validValues = array();

        array_walk($values, function($value, $key) use (&$fields, &$validValues) {
            $fields[] = sprintf("`%s`", $key);
            $validValues[] = sprintf("'%s'", $this->real_escape_string($value));
        });

        $sql = sprintf("%s INTO `%s` (%s) VALUES (%s)", $replace ? "REPLACE" : "INSERT", $tableName, join(",", $fields), join(",", $validValues));

        return $this->query($sql);
    }
}

class DBException extends Exception {}