<?
define('__HOST__',"localhost");
define('__USERNAME__',"root");
define('__PASSWORD__',"");
define('__DATABASE__',"sampledatabase");


// the sql singelton object of _mysql class
function sql($query=null,$return_result = false) {
    global $_mysql;
    if (!isset($_mysql)) {
        $_mysql = new _mysql( __HOST__, __USERNAME__, __PASSWORD__ , __DATABASE__ );
    }
    if ($query!==null) {
        return $_mysql->execute($query,$return_result);
    }
    return $_mysql;
}

// sample 1 --> insert
/*
$row = array("id"=>"1", "name" => "John" , "age" => "30");
$result_id = sql()->insert("persons",$row);
if ( $result_id != null  ) {
    echo "inserted new row!";
} else {
    echo mysql_error();
}
*/

// sample 2 --> update
/*
$row = array("name" => "John" , "age" => "31");
$affected_rows = sql()->update("persons",$row," id = 1 ");
if ($affected_rows) {
    echo "$affected_rows row(s) updated!";
} else {
    if ($err = mysql_error()) {
        echo $err;
    } else {
        echo "No rows affected!";
    }
}
*/




// THE MYSQL WRAPPER CLASS
class _mysql {
    private $link;
    private $result;

    // BASIC
    function __construct($host,$username=null,$password=null,$database=null) {
        $this->connect($host,$username=null,$password=null,$database=null);
        return $this;
    }

    function __destruct() {
        $this->close();
    }

    function connect($host,$username=null,$password=null,$database=null) {
        if (is_array($host)) extract($host);
        $this->link = mysql_connect($host,$username,$password);
        mysql_select_db($database);
        return $this->result;
    }

    function close() {
        @mysql_close($this->link);
    }

    function execute($q,$return_result=false) {
        $this->result = mysql_query($q);
        return ($return_result) ? $this->result : $this;
    }
    // DATA ADJUSTMENTS
    public function secure($data) {
        if (is_array($data)) {
            foreach ($data as $i=>$d) {
                $data[$i] = mysql_real_escape_string($d);
            }
        } else {
            $data = mysql_real_escape_string($data);
        }
        return $data;
    }

    // QUERY BUILDING
    public function generate_fields($data) { // note: All values get secured
        $fields = $values = array();
        foreach ($data as $key=>$value) {
                $fields[]="`".$key."`";
                $values[]="\"".$this->secure($value)."\"";
        }
        return array( $fields, $values );
    }


    // COMMON QUERIES
    public function insert($table,$data) { // inserts a single row into table
        list($fields,$values) = $this->generate_fields($data);
        $fields="(".implode(",",$fields).")";
        $values="(".implode(",",$values).")";
        $q = "insert into `$table` {$fields} values {$values};";
        $this->execute($q);
        return mysql_insert_id();
    }

    public function update($table,$data,$where,$limit='') {
        if ($where) $where="where $where";
        if ($limit) $limit="limit $limit";

        list( $fields, $values ) = $this->generate_fields($data);
        foreach ($fields as $key=>$field) {
            $updates[]="{$field}={$values[$key]}";
        }
        $updates=implode(",",$updates);
        $q="update `$table` set {$updates} $where $limit;";
        $this->execute($q);
        return mysql_affected_rows();
    }


    public function delete($table,$where='',$limit='') {
        if ($where) $where="where $where";
        if ($limit) $limit="limit $limit";
        $this->execute("delete from `$table` $where $limit;");
        return mysql_affected_rows();
    }

}
?>