#!/usr/bin/php
<?php
chdir('/home/ivo/projects/pnewss');
require_once './pdo.php';
require_once './config.php';

$logfile = fopen('./server.log', 'w');
$currentgroup = NULL;
$currentarticle = NULL;

function exception_handler($exception) {
	nntp_writeline(STDOUT, '');
	nntp_writeline(STDOUT, '590 Exception: '.$exception->getMessage());
	die();
}
function error_handler($errno, $errstr, $errfile, $errline) {
	nntp_writeline(STDOUT, '');
	nntp_writeline(STDOUT, '590 Error in file '.$errfile.' line '.$errline.' error '.$errno.' '.$errstr);
	die();
}
set_exception_handler('exception_handler');
set_error_handler("error_handler");

nntp_writeline(STDOUT, '200 pNewss ready');
while (TRUE) {
	$line = nntp_readline(STDIN);
	if ($line === FALSE || $line === NULL) break;	
	$cmd = strtok($line, " \t");
	switch (strtoupper($cmd)) {
		case 'LIST':
			nntp_writeline(STDOUT, '215 List of groups follows');
			foreach ($db->evalAllAssoc('SELECT * FROM `groups`') as $group) {
				$groupmessages = $db->evalRow('SELECT MIN(`number`), MAX(`number`) FROM `groupmessages` WHERE `group` = ?', $group['id']);
				nntp_writeline(STDOUT, $group['name'].' '.intval($groupmessages[1]).' '.intval($groupmessages[0]).' n');
			}
			nntp_writeline(STDOUT, '.');
			break;
		case 'GROUP':
			$groupname = strtok(" \t");
			$group = $db->evalRowAssoc('SELECT * FROM `groups` WHERE `name` = ?', $groupname);
			if ($group === FALSE) {
				nntp_writeline(STDOUT, '411 No such group '.$groupname);
			} else {
				$currentgroup = $group;
				$groupmessages = $db->evalRow('SELECT MIN(`number`), MAX(`number`), COUNT(`number`) FROM `groupmessages` WHERE `group` = ?', $group['id']);
				nntp_writeline(STDOUT, '211 '.intval($groupmessages[2]).' '.intval($groupmessages[0]).' '.intval($groupmessages[1]).' '.$group['name']);
				if ($groupmessages[0] === NULL) {
					$currentarticle = NULL;
				} else {
					$currentarticle = $db->evalRowAssoc('SELECT * FROM `groupmessages` WHERE `group` = ? AND `number` = ?', array($group['id'], $groupmessages[0]));
					if ($currentarticle === FALSE) $currentarticle = NULL;
				}
			}
			break;
		case 'STAT':
			$article = nntp_get_article(strtok(" \t"));
			if ($article === NULL) break;
			nntp_writeline(STDOUT, '223 '.$article['messagenumber'].' <'.$article['messageid'].'> stat');
			break;
		case 'HEAD':
			$article = nntp_get_article(strtok(" \t"));
			if ($article === NULL) break;
			nntp_writeline(STDOUT, '221 '.$article['messagenumber'].' <'.$article['messageid'].'> head');
			foreach (explode("\r\n", $article['header']) as $line) nntp_writeline(STDOUT, $line);
			nntp_writeline(STDOUT, '.');
			break;
		case 'BODY':
			$article = nntp_get_article(strtok(" \t"));
			if ($article === NULL) break;
			nntp_writeline(STDOUT, '222 '.$article['messagenumber'].' <'.$article['messageid'].'> body');
			foreach (explode("\r\n", $article['body']) as $line) nntp_writeline(STDOUT, $line);
			nntp_writeline(STDOUT, '.');
			break;
		case 'ARTICLE':
			$article = nntp_get_article(strtok(" \t"));
			if ($article === NULL) break;
			nntp_writeline(STDOUT, '220 '.$article['messagenumber'].' <'.$article['messageid'].'> article');
			foreach (explode("\r\n", $article['header']) as $line) nntp_writeline(STDOUT, $line);
			nntp_writeline(STDOUT, '');
			foreach (explode("\r\n", $article['body']) as $line) nntp_writeline(STDOUT, $line);
			nntp_writeline(STDOUT, '.');
			break;
		case 'LAST':
			if ($currentarticle === NULL) {
				nntp_writeline(STDOUT, '420 no current article has been selected');
				break;
			}
			$article = $db->evalRowAssoc('SELECT * FROM `groupmessages` WHERE `group` = ? AND `number` < ? ORDER BY `number` DESC LIMIT 1', array($currentarticle['group'], $currentarticle['number']));
			if ($article === FALSE) {
				nntp_writeline(STDOUT, '422 no previous article in this group');
			} else {
				$articlea = $db->evalRowAssoc('SELECT * FROM `messages` WHERE `id` = ?', $article['message']);
				if ($articlea === FALSE) {
					nntp_writeline(STDOUT, '430 no such article found');
					return NULL;
				}
				$currentarticle = $article;
				nntp_writeline(STDOUT, '223 '.$article['number'].' <'.$articlea['messageid'].'> ok');
			}
			break;
		case 'NEXT':
			if ($currentarticle === NULL) {
				nntp_writeline(STDOUT, '420 no current article has been selected');
				break;
			}
			$article = $db->evalRowAssoc('SELECT * FROM `groupmessages` WHERE `group` = ? AND `number` > ? ORDER BY `number` ASC LIMIT 1', array($currentarticle['group'], $currentarticle['number']));
			if ($article === FALSE) {
				nntp_writeline(STDOUT, '422 no previous article in this group');
			} else {
				$articlea = $db->evalRowAssoc('SELECT * FROM `messages` WHERE `id` = ?', $article['message']);
				if ($articlea === FALSE) {
					nntp_writeline(STDOUT, '430 no such article found');
					return NULL;
				}
				$currentarticle = $article;
				nntp_writeline(STDOUT, '223 '.$article['number'].' <'.$articlea['messageid'].'> ok');
			}
			break;
		case 'QUIT':
			nntp_writeline(STDOUT, '205 .');
			return;
		case 'XOVER':
		case 'MODE':
		case 'CAPABILITIES':
			nntp_writeline(STDOUT, '500 Command not implemented');
			break;
		default:
			nntp_writeline(STDOUT, '500 Command not understood');
			break;
	}
}

function nntp_get_article($article) {
	global $currentgroup, $currentarticle, $db;
	if ($article === FALSE) {
		if ($currentarticle === NULL) {
			nntp_writeline(STDOUT, '420 no current article has been selected');
			return NULL;
		}
		$messagenumber = $currentarticle['number'];
		$article = $db->evalRowAssoc('SELECT * FROM `messages` WHERE `id` = ?', $currentarticle['message']);
		if ($article === FALSE) {
			nntp_writeline(STDOUT, '430 no such article found');
			return NULL;
		}
	} elseif (strlen($article) > 2 && $article[0] == '<' && $article[strlen($article)-1] == '>') {
		$messagenumber = 0;
		$article = substr($article, 1, -1);
		$article = $db->evalRowAssoc('SELECT * FROM `messages` WHERE `messageid` = ?', $article);
		if ($article === FALSE) {
			nntp_writeline(STDOUT, '430 no such article found');
			return NULL;
		}
	} elseif (is_numeric($article)) {
		if ($currentgroup === NULL) {
			nntp_writeline(STDOUT, '412 no newsgroup has been selected');
			return NULL;
		}
		$article = $db->evalRowAssoc('SELECT * FROM `groupmessages` WHERE `group` = ? AND `number` = ?', array($currentgroup['id'], $article));
		if ($article === FALSE) {
			nntp_writeline(STDOUT, '423 no such article number in this group');
			return NULL;
		}
		$currentarticle = $article;
		$messagenumber = $article['number'];
		$article = $db->evalRowAssoc('SELECT * FROM `messages` WHERE `id` = ?', $article['message']);
		if ($article === FALSE) {
			nntp_writeline(STDOUT, '430 no such article found');
			return NULL;
		}
	} else {
		nntp_writeline(STDOUT, '500 Error in arguments');
	}
	$article['messagenumber'] = $messagenumber;
	return $article;
}

function writelog($line) {
	global $logfile;
	fwrite($logfile, $line."\n");
}
function nntp_readline($socket) {
	global $logfile;
	$line = fgets($socket, 512);
	if ($line === FALSE || $line === NULL) return $line;
	$line = rtrim($line, "\r\n");
	fwrite($logfile, 'R: '.$line."\n");
	return $line;
}
function nntp_writeline($socket, $line) {
	global $logfile;
	fwrite($logfile, 'W: '.$line."\n");
	fwrite($socket, $line."\r\n");
}
function nntp_readlines($socket) {
	$line = nntp_readline($socket);
	$lines = array();
	while ($line != '.' && $line !== FALSE && $line !== FALSE) {
		$lines[] = $line;
		$line = nntp_readline($socket);
	}
	if ($line != '.') die("Unexpected end of message header\n");
	return $lines;
}