<?php

class db {

    protected $db;
    private $db_host = "localhost";
    private $db_user = "root";
    private $db_pass = "root";
    private $db_name = "mvc";
    private $sql;
    private $stmt;
    private $result;
    private $row = array();

    private function __construct() {

    }

    public function connect_error() {
        echo "DB ERROR. If issue persist contact system Admin";
        exit();
    }

    public function error() {
        echo "Error has with the DB";
        exit();
    }

    public function _connect() {
        $this->db = new mysqli($this->db_host, $this->db_user, $this->db_pass, $this->db_name);
        if (mysqli_connect_errno()) {
            $this->connect_error();
        }

        mysqli_set_chartset($this->db, "utf8");
    }

    /**
     * Insert into DB
     */
    public function query($sql, $params = NULL, $sanitize = TRUE) {

        $this->$sql = $this->sanitize($sql, $sanitize);

        if (!$this->stmt = $this->db->prepare($this->sql)) {
            $this->error();
            return false;
        }

        if (is_array($params)) {
            $this->bindparams($params);
        }

        if (!$this->stmt->execute()) {
            $this->error();
        }

        $this->stmt->reset();
        $this->stmt->close();
    }

    public function fetch_val($sql, $bindparams = NULL, $sanitize = TRUE) {
        $this->$sql = $this->sanitize($sql);

        if ($this->sql = $this->db->prepare($this->sql) != TRUE) {
            $this->error();
        }

        if ($this->stmt->execute() != TRUE) {
            $this->error();
            exit();
        } else {
            $this->result = $this->stmt->get_result();
            return $this->result;
        }


        $this->stmt->free_result();
        $this->stmt->close();
    }

    protected function bindparams($arrParams) {
        $params = array();
        $params[0] = "";

        foreach ($arrParams as $key => $value) {
            $params[0] .= $this->gettype($value);
            array_push($params, $arrParams[$key]);
        }

        call_user_func_array(array($this->stmt, 'bind_param'), $params);
    }

    /**
     * returns type of value
     */
    protected function gettype($var) {
        switch (gettype($var)) {
            case 'NULL':
            case 'string':
                return 's';
                break;
            case 'boolean':
            case 'interger':
                return 'i';
                break;
            case 'blob':
                return 'b';
                break;
            case 'double':
                return 'd';
                break;
        }
    }

    /**
     * sanitize the value
     */
    protected function sanitize($sql) {
        $str_sanitized = ($sanitize) ? filter_var($sql, FILTER_SANITIZE_STRING, FITLER_FLAG_NO_ENCODE_QUOTES) : $sql;
        return $str_sanitized;
    }

    /**
     * close db connection
     */
    public function _close() {
        $this->db->close();
    }

}