<?php

class Database {
  private $db;
  private $error_log = false;
  private $error_mail = false;
  private $lastInsertTable = null;

  public function __construct($driver, $host, $dbname, $user, $passwd)
  {
    $this->db = new PDO(sprintf('%s:host=%s;dbname=%s', $driver, $host, $dbname), $user, $passwd);
    $this->db->query("SET DateStyle = 'ISO'");

    #    $this->db->query("SET NAMES 'utf8'"); 
    #    $this->db->query("SET CHARACTER SET 'utf8'");
    #    $this->db->query("SET collation_connection = 'utf8_general_ci'");
    #    $this->db->query("SET lc_time_names = 'de_DE'");
  }

  public function enableErrorLog()
  {
    $this->error_log = true;
  }

  public function disableErrorLog()
  {
    $this->error_log = false;
  }

  public function setErrorMail($address)
  {
    $this->error_mail = $address;
  }

  private function logQuery($sql)
  {
    if ($this->error_log) error_log(trim(str_replace("\n", ' ', $sql)));
  }

  private function handleError($sth, $sql, $data=false)
  {
    if (!$this->error_log) error_log(trim(str_replace("\n", ' ', $sql)));
    $arr = $this->db->errorInfo();
    foreach (explode("\n", $arr[2]) as $line)
      error_log($line);

    if ($this->error_mail && defined('MAIL_FROM') && defined('MAIL_FROM_NAME')) {
      $mail = new Mail();
      $mail->env_from(MAIL_FROM);
      $mail->set('From', mb_encode_mimeheader(utf8_decode(sprintf("%s <%s>", MAIL_FROM_NAME, MAIL_FROM)),'latin1'));
      $mail->set('To', $this->error_mail);
      $mail->set('Subject', 'SQL Error in ' . $_SERVER['REQUEST_URI']);

      $body = sprintf("http://%s%s%s\nReferer: %s\nUser: %s\n\n%s\n\nError Number %d\n%s\n\n",
		      $_SERVER['SERVER_NAME'],
		      $_SERVER['SERVER_PORT'] != 80 ? ':'.$_SERVER['SERVER_PORT'] : '',
		      $_SERVER['REQUEST_URI'],
		      $_SERVER['HTTP_REFERER'],
		      $_SESSION['sys']['login'],
		      trim($sql),
		      $arr[1],
		      $arr[2]);

      ob_start();
      debug_print_backtrace();
      $body .= ob_get_contents()."\n";
      ob_end_clean();

      if (count($_POST)) $body .= 'POST: ' . var_export($_POST,true)."\n";
      if (count($_GET)) $body .= 'GET: ' . var_export($_GET,true)."\n";
      if (count($_SESSION)) $body .= 'SESSION: ' . var_export($_SESSION,true)."\n";
      if ($data) $body .= 'data: ' . var_export($data,true)."\n";

      $mail->send($body);
    }
    return $sth;
  }

  public function errorInfo()
  {
    return $this->db->errorInfo();
  }

  public function quote($string)
  {
    if (is_null($string)) return 'NULL';
    if (strtolower($string) == 'now()' || strtolower($string) == 'current_timestamp') return 'now()';
    return $this->db->quote($string);
  }

  public function lastInsertId()
  {
    if (DBDRIVER == 'pgsql')
      return $this->db->lastInsertId($this->lastInsertTable.'_id_seq');
    else
      return $this->db->lastInsertId();
  }

  private function query($sql)
  {
    $this->logQuery($sql);
    $sth = $this->db->query($sql);

    if ($sth === false) return $this->handleError($sth,$sql);

    if (preg_match('/INSERT\s+INTO\s+(\S+)\s+/i', $sql, $matches))
      $this->lastInsertTable = $matches[1];

    return $sth;
  }

  public function execute($sql)
  {
    return $this->query($sql) !== false;
  }

  public function fetchValue($sql)
  {
    $sth = $this->query($sql);
    if ($sth === false) return false;
    $ret = $sth->fetch(PDO::FETCH_BOTH);
    if ($ret === false) return false;
    return $ret[0];
  }

  public function fetchAssoc($sql)
  {
    $sth = $this->query($sql);
    if ($sth === false) return false;
    return $sth->fetch(PDO::FETCH_ASSOC);
  }

  public function fetchObject($sql)
  {
    $sth = $this->query($sql);
    if ($sth === false) return false;
    return $sth->fetchObject();
  }

  public function fetchAssocList($sql)
  {
    $result = array();
    $sth = $this->query($sql);
    if ($sth === false) return $result;
    while ($row = $sth->fetch(PDO::FETCH_ASSOC))
      $result[] = $row;
    return $result;
  }

  public function fetchObjectList($sql)
  {
    $result = array();
    $sth = $this->query($sql);
    if ($sth === false) return $result;
    while ($row = $sth->fetchObject())
      $result[] = $row;
    return $result;
  }

  private function executeBind($sql, $data)
  {
    $sth = $this->db->prepare($sql);
    if ($sth === false) return $this->handleError($sth,$sql);

    foreach ($data as $key => $value) {
      if(is_int($value))
	$param = PDO::PARAM_INT;
      elseif(is_float($value))
	$param = PDO::PARAM_STR;
      elseif(is_bool($value))
	$param = PDO::PARAM_BOOL;
      elseif(is_null($value))
	$param = PDO::PARAM_NULL;
      elseif(is_string($value))
	$param = PDO::PARAM_STR;
      else
	$param = FALSE;

      $sth->bindValue(':'.$key, $value, $param);
    }

    $ok = $sth->execute();
    if ($ok === false) return $this->handleError($sth,$sql,$data);

    if (preg_match('/INSERT\s+INTO\s+(\S+)\s+/i', $sql, $matches))
      $this->lastInsertTable = $matches[1];

    return $ok;
  }

  public function insertInto($table, $data)
  {
    if (!is_array($data)) throw new Exception('insertInto called without data array');

    $columns = array();
    foreach ($data as $k => $v) {
      $columns[] = $k;
      if (strtolower($v) == 'now()' || strtolower($v) == 'current_timestamp') {
	$values[] = 'now()';
	unset($data[$k]);
      } else
	$values[] = ':' . $k;
    }

    $sql = sprintf("INSERT INTO %s (%s) VALUES (%s)",
		   $table,
		   implode(',', $columns),
		   implode(',', $values));
    return $this->executeBind($sql, $data);
  }

  public function update($table, $data, $condition)
  {
    if (!is_array($data)) throw new Exception('update called without data array');
    if (empty($condition)) throw new Exception('update called without condition');

    $set = array();
    foreach ($data as $k => $v) {
      if (strtolower($v) == 'now()' || strtolower($v) == 'current_timestamp') {
	$set[] = $k.'=now()';
	unset($data[$k]);
      } else
	$set[] = $k.'=:'.$k;
    }

    $sql = sprintf("UPDATE %s SET %s WHERE %s",
		   $table,
		   implode(',', $set),
		   $condition);
    return $this->executeBind($sql, $data);
  }

  public function delete($table, $idcolumn, $id)
  {
    $sql = sprintf("DELETE FROM %s WHERE %s = %d",
		   $table, $idcolumn, $id);
    return $this->execute($sql);
  }

}

?>