log state when sent MsgNo 0 - do not stop, just log

peeker.php

@@ -129,7 +129,10 @@ public function get_message($start, $end=NULL)
 	public function message($start, $end=NULL)
 	{
 		// protect the command from 
-		// using empty string like NULL
+		// using empty string like NULL or 0
+		// because messages start at MsgNo 1, not 0
+		// TODO: add exception, better error handling
+		if ($start===0) $this->log_state('ERROR: MsgNo cannot be 0. Mail server MsgNo starts at 1.');
 		// force it to message 1
 		// should change this to error
 		$start = ($start==='') ? 1 : $start;
@@ -754,7 +757,7 @@ public function make_detector_set()
 	{
 		include_once('peeker_detector_set.php');
 		// make a new one if we don't have it already
-		if ($this->detector_set === NULL) $this->detector_set = new peeker_detector_set();
+		if (!isset($this->detector_set)) $this->detector_set = new peeker_detector_set();
 		$this->detectors_on = TRUE;
 		return $this->detector_set;
 	}

peeker_body.php

@@ -75,7 +75,13 @@ public function get_body()
 			// it effectively invisible (depending on gmail account's POP3 settings)
 			$this->log_state('Fetching structure for email #'.$this->Msgno);			
 			$structure = @imap_fetchstructure($this->peek_parent->resource, $this->Msgno);
-			// check for errors here to clear the 
+
+			// make sure $structure is not null - can happen if passed MsgNo 0
+			// log state
+			// TODO: build error handling, exception
+			if ($structure===NULL) $this->log_state('get_body() method $structure is NULL. MsgNo is: '.(int)$this->MsgNo);
+
+			// check for mail server errors here to clear the 
 			// error stack and prevent it from posting
 			// PHP errors about badly formatted emails
 			// should probably store the errors with the email in a db