<?php

class db
{
    public $link = null;
    public $last_query = null;

    private $host = 'localhost';
    private $user = 'root';
    private $password = '';

    public $dbName = 'krossport';

    public function __construct()
    {
        $this->link = mysqli_connect($this->host, $this->user, $this->password, $this->dbName) or die('');

        mysqli_query($this->link, "SET NAMES utf8");
    }

    public function query($q = null)
    {
        $this->last_query = mysqli_query($this->link, $q);

        return $this->last_query;
    }

    /*
     Создание записи в таблице. Пример использования:

     $db->insert('users', array('id' => NULL, 'login' => 'test'));
    */
    public function insert($tableName = null, $params = null)
    {
        foreach ($params as $key => $value) {
            $keys[] = '`' . $key . '`';
            $values[] = "'" . $this->escape($value) . "'";
        }

        return $this->query("INSERT INTO `" . $this->dbName . "`.`" . $tableName . "` (" . implode(', ', $keys) . ") VALUES (" . implode(', ', $values) . ");");
    }
    /*
     Изменение записи в таблице. Примеры использования:

     $db->update('users', array('login' => 'new_login'), array('user_id' => 1));
     $db->update('users', array('reputation:+' => 1), array('user_id' => 1)); // прибавит +1 к reputation
    */
    public function update($tableName = null, $params = null, $where = null)
    {
        foreach ($params as $key => $value) {
            if (preg_match('/\:/is', $key)) {
                preg_match('/[\+\-\*]/is', $key, $sign);

                $result[] = "`" . str_replace(':' . $sign[0], '', $key) . "` = `" . str_replace(':' . $sign[0], '', $key) . "` " . $sign[0] . " " . $value . "";
            } else {
                $result[] = "`" . $key . "` = '" . $this->escape($value) . "'";
            }
        }

        foreach ($where as $key => $value) {
            $result_where[] = "`" . $tableName . "`.`" . $key . "` = '" . $this->escape($value) . "'";
        }

        $where = ((isset($where)) ? " WHERE " . implode(' AND ', $result_where) . "" : '');

        return $this->query("UPDATE `" . $this->dbName . "`.`" . $tableName . "` SET " . implode(', ', $result) . "" . $where . ";");
    }

    public function in($tableName = null, $fields = array(), $in_field = null, $in = null, $where = null)
    {
        for ($i = 0; $i < count($fields); $i++) {
            $result_fields[] = '`' . $fields[$i] . '`';
        }

        for ($i = 0; $i < count($in); $i++) {
            $result_in[] = '\'' . $in[$i] . '\'';
        }

        if ($where) {
            foreach ($where as $key => $value) {
                $result_where[] = "`" . $tableName . "`.`" . $key . "` = '" . $this->escape($value) . "'";
            }
        }

        $where = ((isset($where)) ? implode(' AND ', $result_where) . "" : '');

        $q = $this->query("SELECT " . implode(',', $result_fields) . " FROM `" . $tableName . "` WHERE `" . $in_field . "` IN(" . implode(',', $result_in) . ") " . $where . ";");

        $result_d = array();

        while ($d = $this->assoc($q)) {
            $result_d[$d[$in_field]] = $d;
        }

        return $result_d;
    }

    public function fetch($q = null)
    {
        return mysqli_fetch_array($q);
    }

    public function assoc($q = null)
    {
        return mysqli_fetch_assoc($q);
    }

    public function escape($q = null)
    {
        return mysqli_real_escape_string($this->link, $q);
    }

    public function insertId()
    {
        return mysqli_insert_id($this->link);
    }

    public function filter($text = null)
    {
        return htmlspecialchars(stripslashes($text));
    }

    public function br($text = null)
    {
        return str_replace("\n", "<br />", $text);
    }

    public function error()
    {
        return mysqli_error($this->link);
    }

    public function __destruct()
    {
        return mysqli_close($this->link);
    }
}