<?php
/** DomFramework
    @package domframework
    @author Dominique Fournier <dominique@fournier38.fr> */

/** The logger class permit to log the information from the soft
    It allow to debug too */
class logger
{
  /* The logger class can be used with :
     $d=new logger;
     $d->timezone = "Europe/Paris";
     $d->logtype="display|file";
     $d->logfile="/tmp/toto.log";
     $d->logwrite ("Super log default");
     $d->logwrite ("Super log DEBUG", $d::DEBUG);
     $d->logwrite ("Super log NOTICE", $d::NOTICE); */
  // TODO : Add SQL support
  /** The method to log.
      Can be display, file, syslog, stderr, session
      Can be merged with a pipe : "display|syslog|file" or put in array */
  public $logtype = "stderr";
  /** For logtype=file, the filename to use */
  public $logfile = FALSE;
  /** Timezone use to save the logs */
  public $timezone = "UTC";
  /** Minimum log level in the logs */
  public $loglevelmin = LOG_NOTICE;
  /** In Syslog mode, the facility to use
    See http://fr2.php.net/manual/en/function.openlog.php for $syslogFacility */
  public $syslogFacility = LOG_USER;
  /** In Syslog, prefix the log by the text */
  public $syslogPrefix = FALSE;
  /** Remove X entries of backtrace to see the right file generating the error
    */
  public $backTraceSkip = 1;
  /** Display the backtrace in all the messages */
  public $backtraceDisplay = false;

  /** The priorities which can be used in the priorities
  LOG_EMERG   system is unusable
  LOG_ALERT   action must be taken immediately
  LOG_CRIT    critical conditions
  LOG_ERR     error conditions
  LOG_WARNING warning conditions
  LOG_NOTICE  normal, but significant, condition
  LOG_INFO    informational message
  LOG_DEBUG   debug-level message */
  private $priorities = array (LOG_EMERG   => "EMERG",
                               LOG_ALERT   => "ALERT",
                               LOG_CRIT    => "CRITICAL",
                               LOG_ERR     => "ERROR",
                               LOG_WARNING => "WARNING",
                               LOG_NOTICE  => "NOTICE",
                               LOG_INFO    => "INFO",
                               LOG_DEBUG   => "DEBUG");

  /** Catch all the messages raised by the PHP, in trigger_error
      Use the properties of the logger to save the logs */
  public function catchAll ()
  {
    set_error_handler (array (&$this, "errorHandler"));
  }

  /** The error handler to log
    * @param integer $errno The error number to use
    * @param string $errstr The error message to save
    * @param string $errfile The file which generate the error
    * @param integer $errline The line where the error is generated
    */
  public function errorHandler ($errno, $errstr, $errfile, $errline)
  {
    if (!(error_reporting() & $errno))
    {
        // This error code is not included in error_reporting
        return;
    }
    switch($errno)
    {
      case E_ERROR:             $priority = LOG_ERR; break;
      case E_WARNING:           $priority = LOG_WARNING; break;
      case E_PARSE:             $priority = LOG_PARSE; break;
      case E_NOTICE:            $priority = LOG_NOTICE; break;
      case E_CORE_ERROR:        $priority = LOG_ERR; break;
      case E_CORE_WARNING:      $priority = LOG_WARNING; break;
      case E_COMPILE_ERROR:     $priority = LOG_ERR; break;
      case E_COMPILE_WARNING:   $priority = LOG_WARNING; break;
      case E_USER_ERROR:        $priority = LOG_ERR; break;
      case E_USER_WARNING:      $priority = LOG_WARNING; break;
      case E_USER_NOTICE:       $priority = LOG_NOTICE; break;
      case E_STRICT:            $priority = LOG_WARNING; break;
      case E_RECOVERABLE_ERROR: $priority = LOG_ERR; break;
      case E_DEPRECATED:        $priority = LOG_WARNING; break;
      case E_USER_DEPRECATED:   $priority = LOG_WARNING; break;
    }
    $this->log ($priority, $errstr);
  }

  /** Store a new message log in the log manager defined by $logtype
      The message can be multiple types. An array will be stored in textual form
      but it will accept only one depth.
      The $message is not fixed, you can pass the number of parameters you want
      @param integer|null $priority Priority to use
      @param mixed ...$message Message to log */
  public function log ($priority=LOG_NOTICE, $message)
  {
    if (! is_int ($priority))
    {
      switch ($priority)
      {
      case "LOG_EMERG":   $priority = LOG_EMERG;   break;
      case "LOG_ALERT":   $priority = LOG_ALERT;   break;
      case "LOG_CRIT":    $priority = LOG_CRIT;    break;
      case "LOG_ERR":     $priority = LOG_ERR;     break;
      case "LOG_WARNING": $priority = LOG_WARNING; break;
      case "LOG_NOTICE":  $priority = LOG_NOTICE;  break;
      case "LOG_INFO":    $priority = LOG_INFO;    break;
      case "LOG_DEBUG":   $priority = LOG_DEBUG;   break;
      }
    }
    if (! is_int ($this->loglevelmin))
    {
      switch ($this->loglevelmin)
      {
      case "LOG_EMERG":   $this->loglevelmin = LOG_EMERG;   break;
      case "LOG_ALERT":   $this->loglevelmin = LOG_ALERT;   break;
      case "LOG_CRIT":    $this->loglevelmin = LOG_CRIT;    break;
      case "LOG_ERR":     $this->loglevelmin = LOG_ERR;     break;
      case "LOG_WARNING": $this->loglevelmin = LOG_WARNING; break;
      case "LOG_NOTICE":  $this->loglevelmin = LOG_NOTICE;  break;
      case "LOG_INFO":    $this->loglevelmin = LOG_INFO;    break;
      case "LOG_DEBUG":   $this->loglevelmin = LOG_DEBUG;   break;
      }
    }
    if ($this->loglevelmin < $priority)
      return;
    $backtrace = debug_backtrace();
    for ($i = 0 ; $i <= $this->backTraceSkip ; $i++)
      $back = array_shift ($backtrace);
    while (! array_key_exists ("file", $back) && count ($backtrace) > 0)
      $back = array_shift ($backtrace);
    $msg = "";
    if (isset ($_SERVER["HTTP_X_FORWARDED_FOR"]))
      $msg .= "[".$_SERVER["HTTP_X_FORWARDED_FOR"]."] ";
    elseif (isset ($_SERVER["REMOTE_ADDR"]))
      $msg .= "[".$_SERVER["REMOTE_ADDR"]."] ";

    // The messages are all the parameters of the function except the first,
    // which is the priority
    $messages = func_get_args ();
    array_shift ($messages);
    // Convert each part of message to text
    foreach ($messages as $m)
    {
      if (is_array ($m))
      {
        $msg .= "[";
        foreach ($m as $key=>$val)
        {
          if (is_array ($val))
          {
            foreach ($val as $key2=>$val2)
            {
              $msg .= "$key2=>$val2,";
            }
          }
          else
          {
            $msg .= "$key=>$val,";
          }
        }
        $msg .= "]";
      }
      else
      {
        $msg .= $m;
      }
    }

    // Add the filename which generate the error
    $msg .= " [".basename ($back["file"]).":".$back["line"]."]";

    // Display the backtrace if it is needed
    if ($this->backtraceDisplay)
    {
      $e = new Exception();
      $msg .= "\n".($e->getTraceAsString());
    }

    if (is_string ($this->logtype))
      $logsType = explode ("|", $this->logtype);
    elseif (is_array ($this->logtype))
      $logsType = $this->logtype;
    if (in_array ("display", $logsType))
      $this->logdisplay ($msg, $priority);
    if (in_array ("stderr", $logsType))
      $this->logstderr ($msg, $priority);
    if (in_array ("file", $logsType))
      $this->logfile ($msg, $priority);
    if (in_array ("syslog", $logsType))
      $this->logsyslog ($msg, $priority);
    if (in_array ("session", $logsType))
      $this->logsession ($msg, $priority);
  }

  /** Log $message on file
      @param string $message Message to log
      @param integer|null $priority Priority to use */
  private function logfile ($message, $priority)
  {
    if ($this->logfile === FALSE)
      throw new Exception ("Undefined file where logging");
    if (!file_exists ($this->logfile))
    {
      if (! is_dir (dirname ($this->logfile)))
        throw new Exception ("You must create the ".dirname ($this->logfile).
                             "directory");
      if (! is_writable (dirname ($this->logfile)))
        throw new Exception ("The directory ".dirname ($this->logfile)." must"
                            ." be writable to create log file");
    }
    elseif (!is_writable ($this->logfile))
    {
      if (function_exists ("posix_geteuid"))
        $user = posix_geteuid ();
      elseif (getenv('USERNAME') !== FALSE)
        $user = getenv('USERNAME');
      else
        $user = "";
      throw new Exception ("Logfile $this->logfile is not writable for user ".
                           $user);
    }

    ini_set ("date.timezone", $this->timezone);
    $message = date ("Y/m/d H:i:s")." [".$this->priorities[$priority]."] ".
               $message."\n";
    file_put_contents ($this->logfile, $message, FILE_APPEND|LOCK_EX);
  }

  /** Log $message on screen with adding date. Add the HTML flags if not in CLI.
      @param string $message Message to log
      @param integer|null $priority Priority to use */
  private function logdisplay ($message, $priority)
  {
    if (php_sapi_name () !== "cli")
      echo "<tt>";
    ini_set ("date.timezone", $this->timezone);
    $message = date ("Y/m/d H:i:s")." [".$this->priorities[$priority]."] ".
               $message;
    if (php_sapi_name () !== "cli")
      $message = nl2br ($message);
    echo "$message";
    if (php_sapi_name () !== "cli")
      echo "</tt><br/>";
    echo "\n";
  }

  /** Log $message on stderr with adding date. Add the HTML flags if not in CLI.
      @param string $message Message to log
      @param integer|null $priority Priority to use */
  private function logstderr ($message, $priority)
  {
    ini_set ("date.timezone", $this->timezone);
    $message = date ("Y/m/d H:i:s")." [".$this->priorities[$priority]."] ".
               $message;
    file_put_contents("php://stderr", "$message");
    file_put_contents("php://stderr", "\n");
  }

  /** Log $message on syslog
      @param string $message Message to log
      @param integer|null $priority Priority to use */
  private function logsyslog ($message, $priority)
  {
    if (is_string ($this->syslogFacility))
    {
      switch ($this->syslogFacility)
      {
      case "LOG_AUTH":     $this->syslogFacility=LOG_AUTH;     break;
      case "LOG_AUTHPRIV": $this->syslogFacility=LOG_AUTHPRIV; break;
      case "LOG_DAEMON":   $this->syslogFacility=LOG_DAEMON;   break;
      case "LOG_KERN":     $this->syslogFacility=LOG_KERN;     break;
      case "LOG_LOCAL0":   $this->syslogFacility=LOG_LOCAL0;   break;
      case "LOG_LOCAL1":   $this->syslogFacility=LOG_LOCAL1;   break;
      case "LOG_LOCAL2":   $this->syslogFacility=LOG_LOCAL2;   break;
      case "LOG_LOCAL3":   $this->syslogFacility=LOG_LOCAL3;   break;
      case "LOG_LOCAL4":   $this->syslogFacility=LOG_LOCAL4;   break;
      case "LOG_LOCAL5":   $this->syslogFacility=LOG_LOCAL5;   break;
      case "LOG_LOCAL6":   $this->syslogFacility=LOG_LOCAL6;   break;
      case "LOG_LOCAL7":   $this->syslogFacility=LOG_LOCAL7;   break;
      case "LOG_LPR":      $this->syslogFacility=LOG_LPR;      break;
      case "LOG_MAIL":     $this->syslogFacility=LOG_MAIL;     break;
      case "LOG_NEWS":     $this->syslogFacility=LOG_NEWS;     break;
      case "LOG_SYSLOG":   $this->syslogFacility=LOG_SYSLOG;   break;
      case "LOG_USER":     $this->syslogFacility=LOG_USER;     break;
      case "LOG_UUCP":     $this->syslogFacility=LOG_UUCP;     break;
      }
    }
    openlog ($this->syslogPrefix, NULL, $this->syslogFacility);
    syslog ($priority, $message);
  }

  /** Log $message on session (for debug)
      @param string $message Message to log
      @param integer|null $priority Priority to use */
  private function logsession ($message, $priority)
  {
    if (! isset ($_SESSION))
      throw new Exception ("No session available to store the log", 500);
    ini_set ("date.timezone", $this->timezone);
    $message = date ("Y/m/d H:i:s")." [".$this->priorities[$priority]."] ".
               $message;
    $_SESSION["domframework"]["logger"][] = $message;
  }
}