<?php

class db{
	public $mysqli;
	private $total_queries = 0;
	protected $result = false;


	public function __construct($type){



		if ($this->mysqli->connect_error){
			exit('Unable to establish a connection to your database. Please verify your settings are correct.');
		}

	}

	public function query($sql, $binds = false){

		if ($binds){
			$sql = $this->_binds($sql, $binds);
		}

		if (($this->result = $this->mysqli->query($sql)) === false){
			exit("Invalid query : ".$this->mysqli->error);
			return false;
		}
		return true;
	}

	public function select($select, $table, $where = '', $binds = '', $orderby = '', $order = 'ASC', $limit = 0){

		$sql = 'SELECT ';

		if (!is_array($select)){
			$select = array($select);
		}

		$i = 0;
		foreach ($select as $v){
			$sql .= ($i == 0) ? '' : ',';
			$sql .= $v;
			++$i;
		}

		$sql .= ' FROM ';
		$sql .= $table;

		if (!empty($where)){
			$sql .= ' WHERE '.$where;
		}

		if (!empty($orderby)){
			$sql .= ' ORDER BY '.$orderby.' '.$order;
		}

		if ($limit > 0 || !empty($limit)){
			$sql .= ' LIMIT '.$limit;
        }

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

	public function join($type = '', $select, $tables, $on, $where = '', $binds = '', $orderby = '', $order = 'ASC', $limit = 0){

		$tableSet = '';
		$key = 'a';
		foreach ($tables as $table){
			$tableSet .= DB_PREFIX.$table.' AS '.$key;
			if ($key == 'a'){
				$key = 'b';
				$tableSet .= ' '.$type.' JOIN ';
			}else{
				$tableSet .= ' ON '.$on;
			}
		}
		return $this->select($select, $tableSet, $where, $binds, $orderby, $order, $limit);
	}

	public function result($type = 'object'){
		return ($type == 'array') ? $this->fetch_array() : $this->fetch_object();
	}


	public function insert($table, $args){

		$keys = '';
		$values = '';
		$i = count($args);
		$x = 0;
		foreach ($args as $k => $v){
			++$x;
			$comma = ($x < $i) ? ',' : '';
			$keys .= $k . $comma;
			$values .= $this->cleanse($v) . $comma;
		}
		$sql = 'INSERT INTO '.DB_PREFIX.$table.'('.$keys.') VALUES('.$values.')';
		return $this->query($sql);
	}


	public function update($table, $args = array(), $where = array()){

		$update = '';
		$i = count($args);
		$x = 0;
		foreach ($args as $k => $v){
			++$x;
			$comma = ($x < $i) ? ',' : '';
			$update .= $k.'=\''.$this->_cleanse($v).'\''.$comma;
		}

		$sql = 'UPDATE '.DB_PREFIX.$table.' SET '.$update.' WHERE';
		$and = false;
		foreach ($where as $k => $v){
			if ($and) $sql .= ' AND';
			$sql .= ' '.$k.'=\''.$this->_cleanse($v).'\'';
			$and = true;
		}
		return $this->query($sql);
	}

	public function delete($table, $where, $binds = array()){

		$sql = 'DELETE FROM '.DB_PREFIX.$table.' WHERE '.$where;
		return $this->query($sql, $binds);
	}

	private function fetch_object(){
		return $this->result->fetch_object();
	}


	private function fetch_array(){

		while (($result = $this->result->fetch_assoc())){
			$array[] = $result;
		}
		return $array;
	}

	public function num_rows(){
		return $this->result->num_rows;
	}

	public function insert_id(){
		return $this->mysqli->insert_id;
	}

	private function _binds($sql, $binds){

		if (!is_array($binds)){
			$binds = array($binds);
		}

		$segments = explode('?', $sql);

		if (count($binds) >= count($segments)){
			$binds = array_slice($binds, 0, count($segments) - 1);
		}

		$sql = $segments[0];
		$i = 0;
		foreach ($binds as $bind){
			$sql .= $this->cleanse($bind);
			$sql .= $segments[++$i];
		}

		return $sql;
	}

	private function cleanse($str){

		if (is_string($str)){
			$str = "'".$this->_cleanse($str)."'";
		}

		elseif (is_bool($str)){
			$str = ($str === false) ? 0 : 1;
		}else{
			$str = ($str === NULL) ? 'NULL' : $str;
		}
		return $str;
	}


	private function _cleanse($str){

		if (function_exists('mysqli_real_escape_string')){
			$str = $this->mysqli->real_escape_string($str);
		}else{
			$str = addslashes($str);
		}
		return $str;
	}

	public function close(){
		$this->mysqli->close();
	}

}