<?php

if(phpversion() < 5)
    die('The class DB needs at least PHP5');

class DB{
    var $ressource;
    var $statement;
    var $hide_errors = FALSE;
    var $direct_error_output = TRUE;
    var $connected = FALSE;
    var $statement_set = FALSE;

    var $app = 'App';

    var $host = '';
    var $username = '';
    var $password = '';
    var $database = '';

    function __construct($host, $username, &$password, $database){
        $this->host = $host;
        $this->username = $username;
        $this->password = $password;
        $this->database = $database;

        $password = '';

        $this->connect();

        $this->password = '';
    }

    function connect(){
        //Ignore connection error so we can let the class handle it
        @$this->ressource = new MySQLi($this->host, $this->username, $this->password);
        if(!$this->check_for_sql_errors(TRUE)){
            $this->produce_error('Connection to database could not be established.');
        }

        $this->connected = TRUE;

        if(!empty($this->database))
            $this->select_db();
    }

    function select_db(){
        if(!empty($this->database)){
            $this->ressource->select_db($this->database);
        }
        if(!$this->check_for_sql_errors()){
            $this->produce_error('Database could not be choosen.');
        }
    }

    function set_charset($charset = NULL){
        if($this->connected === TRUE){
            if(!$this->ressource->set_charset($charset)){
                $this->produce_error('Default charset could not be set.');
            }
        }
    }

    function get_sql_version(){
        if($this->connected === TRUE){
            $sql = "SELECT VERSION() AS version";
            $statement = new StmtMySQLi($this->ressource);
            $statement->prepare($sql);
            $statement->execute();
            $version = $statement->getOne();
            $version = $version['version'];
        }
        if(empty($version)) $version = 'unknown';
        return $version;
    }

    function query(){
        $args = func_get_args();

        if($this->connected !== TRUE){
            $this->produce_error('No database connection');
        }

        $this->statement = new StmtMySQLi($this->ressource);
        $this->statement_set = FALSE;

        if(!empty($args[0])){
            $sql = array_shift($args);
            $types = '';
            foreach ($args AS &$value){
                switch ($value){
                    case (is_numeric($value) && filter_var($value, FILTER_SANITIZE_NUMBER_INT)):
                        $types .= 'i';
                        debug(is_int($value), 0);
                        var_dump($value);
                    break;

                    case (is_numeric($value) && filter_var($value, FILTER_SANITIZE_NUMBER_FLOAT, FILTER_FLAG_ALLOW_FRACTION | FILTER_FLAG_ALLOW_THOUSAND)):
                        $types .= 'd';
                    break;

                    case (filter_var($value, FILTER_SANITIZE_STRING)):
                        $types .= 's';
                    break;
                }
            }
            debug($args, 0);
            debug($types);
            if(!$this->statement->prepare($sql)){
                $this->produce_error('Query is invalid');
            }
            else{
                $this->statement_set = TRUE;
                if(isset($args[0])){
                    array_unshift($args, $types);
                    if(!empty($args) && count($args) > 0){
                        if(!call_user_func_array(array($this->statement, 'bind_param'), $args)){
                            $this->produce_error('Parameters are invalid');
                        }
                    }
                }
                $this->statement->execute();
                $this->statement->store_result();
                $this->get_query_info();
                return $this->statement;
            }
        }
        else{
            $this->produce_error('Query must not be empty');
        }
    }

    function fetch_first(){
        $args = func_get_args();

        $statement = call_user_func_array(array($this, 'query'), $args);
        if($statement instanceof StmtMySQLi){
            $result = $statement->getOne();
        }
        else{
            $result = FALSE;
        }

        return $result;
    }

    function fetch_all($statement = -1, $type = MYSQLI_BOTH){
        if($statement == -1) $statement = &$this->statement;
        if($this->check_for_sql_errors() && $statement){
            return $statement->getAll($type);
        }
        else{
            $this->produce_error('No result to fetch from');
        }
    }

    function fetch_array($statement = -1, $type = MYSQLI_BOTH){
        if($statement === -1) $statement = &$this->statement;
        if($this->check_for_sql_errors() && $statement){
            return $statement->getOne($type);
        }
        else{
            $this->produce_error('No result to fetch from');
        }
    }

    function get_query_info(){
        if(($err = $this->check_for_sql_errors()) && $this->statement_set === TRUE){
            if ($this->statement->affected_rows > 0)
                $num_rows = $this->statement->affected_rows;
            else
                $num_rows = $this->statement->num_rows;

            $result['num_rows'] = $num_rows;
            $result['insert_id'] = $this->statement->insert_id;
            $result['err_occ'] = !$err;
        }
        elseif($this->statement_set === FALSE){
            $result['err_occ'] = $err;
            $result['num_rows'] = 0;
        }

        $this->num_rows = $result['num_rows'];

        return $result;
    }

    //Error-Sektion
    function produce_error($error_msg){

        $error = $this->get_sql_error();

        $output = "<b>$this->app SQL Error</b> \n<br />";
        $output .= "<b>An error occurred:</b> $error_msg\n <br />";
        $output .= "<b>mysql error:</b> ".$error['error']."\n <br/>";
        $output .= "<b>mysql error number:</b> ".$error['errorno']."\n <br />";
        $output .= "<b>mysql version:</b> ".$this->get_sql_version()."\n <br />";
        $output .= "<b>php version:</b> ".phpversion()."\n <br />";
        $output .= "<b>Script:</b> ".htmlentities(getenv("REQUEST_URI"))."\n<br>";

        if($this->hide_errors == TRUE)
            $output = "<!-- $output -->";

        if($this->direct_error_output == TRUE){
            die('<h2>SQL DATABASE ERROR</h2> '.$output);
        }
        else{
            return $output;
        }
    }

    function get_sql_error($connect = FALSE){
        $result = array();
        if($connect === TRUE || ($connect == FALSE && mysqli_connect_error())){
            $result['error'] = mysqli_connect_error();
            $result['errorno'] = mysqli_connect_errno();
        }
        else{
            if(!$this->ressource->error){
                $result['error'] = mysqli_error($this->ressource);
                $result['errorno'] = mysqli_errno($this->ressource);
            }
            else{
                $result['error'] = $this->ressource->error;
                $result['errorno'] = $this->ressource->errno;
            }
        }
        return $result;
    }

    //no error occured = TRUE; error occured = FALSE
    function check_for_sql_errors($connect = FALSE){
        $error = $this->get_sql_error($connect);
        if($error['errorno'] === 0)
            return TRUE;
        else
            return FALSE;
    }
}


class StmtMySQLi extends mysqli_stmt
{

    /**
    * Fetch one result (array)
    *
    * @param MYSQLI_RESULTMODE_TYPE $resultmode
    * @return array $result
    */
    public function getOne($resultmode = MYSQLI_BOTH)
    {
        $result = $result_both = $row = array();
        $meta = $this->result_metadata();
        while ($field = $meta->fetch_field()) {
            if(in_array($field->name, array_keys($result), TRUE)){
                $field->name = $field->table.'.'.$field->name;
            }
            switch ($resultmode) {
                case MYSQLI_ASSOC:
                    $result[$field->name] = &$row[$field->name];
                break;

                case MYSQLI_NUM:
                    $result[] = &$row[$field->name];
                break;

                case MYSQLI_BOTH:
                    $result[$field->name] = &$row[$field->name];
                    $result_both[] = &$row[$field->name];
                break;
            }
        }

        call_user_func_array(array($this,'bind_result'), $result);
        if($this->fetch()){
            return $result+$result_both;
        }
        else{
            return FALSE;
        }
    }

    public function getAll($resultmode = MYSQLI_BOTH){
        $result = array();
        while($fetch = $this->getOne($resultmode)){
            $result[] = $fetch;
        }
        return $result;
    }
}

?>