#!/usr/bin/php
<?php
chdir(__DIR__);
require_once './common.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;
	$cmd = strtoupper(strtok($line, " \t"));
	switch ($cmd) {
		case 'CAPABILITIES':
			nntp_writeline(STDOUT, '101 Capability list:');
			nntp_writeline_data(STDOUT, 'VERSION 2');
			nntp_writeline_data(STDOUT, 'IMPLEMENTATION pNewss [http://wiki.ucis.nl/pNewss]');
			nntp_writeline_data(STDOUT, 'POST');
			nntp_writeline_data(STDOUT, 'READER');
			nntp_writeline_data(STDOUT, 'IHAVE');
			nntp_writeline_data(STDOUT, 'LIST ACTIVE');
			nntp_writeline(STDOUT, '.');
			//HDR, LIST, OVER, STARTTLS, STREAMING, 
			break;
		case 'DATE':
			nntp_writeline(STDOUT, '111 '.gmdate('YmdHis'));
			break;
		case 'HELP':
			nntp_writeline(STDOUT, '100 Help text follows:');
			nntp_writeline_data(STDOUT, 'Supported commands: CAPABILITIES,DATE,HELP,LIST,GROUP,LISTGROUP,STAT,HEAD,BODY,ARTICLE,LAST,NEXT,POST,IHAVE,QUIT');
			nntp_writeline(STDOUT, '.');
			break;
		case 'LIST':
			nntp_writeline(STDOUT, '215 list of groups follows');
			foreach ($db->evalAllAssoc('SELECT * FROM `groups`') as $group) {
				$groupmessages = $db->evalRow('SELECT MIN(`number`), MAX(`number`) FROM `groupmessages` WHERE `group` = ?', $group['id']);
				nntp_writeline_data(STDOUT, $group['name'].' '.intval($groupmessages[1]).' '.intval($groupmessages[0]).' n');
			}
			nntp_writeline(STDOUT, '.');
			break;
		case 'GROUP':
		case 'LISTGROUP':
			$groupname = strtok(" \t");
			if ($groupname === FALSE) {
				$group = $currentgroup;
			} else {
				$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) $currentarticle = NULL;
				}
				if ($cmd == 'LISTGROUP') {
					$range = strtok(" \t");
					if ($range !== FALSE) {
						$parts = explode('-', $range);
						if (count($parts) == 1 || !strlen($parts[1])) {
							$query = 'SELECT `number` FROM `groupmessages` WHERE `group` = ? AND `number` >= ?';
							$queryargs = array($group['id'], $parts[0]);
						} else {
							$query = 'SELECT `number` FROM `groupmessages` WHERE `group` = ? AND `number` BETWEEN ? AND ?';
							$queryargs = array($group['id'], $parts[0], $parts[1]);
						}
					} else {
						$query = 'SELECT `number` FROM `groupmessages` WHERE `group` = ?';
						$queryargs = array($group['id']);
					}
					foreach ($db->evalColumn($query, $queryargs) as $number) nntp_writeline_data(STDOUT, $number);
					nntp_writeline(STDOUT, '.');
				}
			}
			break;
		case 'STAT':
		case 'HEAD':
		case 'BODY':
		case 'ARTICLE':
			$article = nntp_get_article(strtok(" \t"));
			if ($article === NULL) break;
			switch ($cmd) {
				case 'ARTICLE': nntp_writeline(STDOUT, '220 '.$article['messagenumber'].' <'.$article['messageid'].'> article'); break;
				case 'HEAD': nntp_writeline(STDOUT, '221 '.$article['messagenumber'].' <'.$article['messageid'].'> head'); break;
				case 'BODY': nntp_writeline(STDOUT, '222 '.$article['messagenumber'].' <'.$article['messageid'].'> body'); break;
				case 'STAT': nntp_writeline(STDOUT, '223 '.$article['messagenumber'].' <'.$article['messageid'].'> stat'); break;
				default: throw new Exception('Internal error');
			}
			if ($cmd == 'HEAD' || $cmd == 'ARTICLE') foreach (explode("\r\n", $article['header']) as $line) nntp_writeline_data(STDOUT, $line);
			if ($cmd == 'ARTICLE') nntp_writeline(STDOUT, '');
			if ($cmd == 'BODY' || $cmd == 'ARTICLE') foreach (explode("\r\n", $article['body']) as $line) nntp_writeline_data(STDOUT, $line);
			if ($cmd != 'STAT') nntp_writeline(STDOUT, '.');
			break;
		case 'LAST':
		case 'NEXT':
			if ($currentarticle === NULL) {
				nntp_writeline(STDOUT, '420 no current article has been selected');
				break;
			}
			switch ($cmd) {
				case 'LAST': $query = 'SELECT * FROM `groupmessages` WHERE `group` = ? AND `number` < ? ORDER BY `number` DESC LIMIT 1'; break;
				case 'NEXT': $query = 'SELECT * FROM `groupmessages` WHERE `group` = ? AND `number` > ? ORDER BY `number` ASC LIMIT 1'; break;
				default: throw new Exception('Internal error');
			}
			$article = $db->evalRowAssoc($query, 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 'POST':
			nntp_writeline(STDOUT, '340 Ok, recommended message-ID <'.md5(time().rand()).'@pNews.Core.UCIS.nl>');
			$lines = nntp_readlines(STDIN);
			try {
				$messageid = nntp_article_store($lines);
				nntp_writeline(STDOUT, '240 Article received <'.$messageid.'>');
			} catch (Exception $ex) {
				nntp_writeline(STDOUT, '441 '.$ex->getMessage());
			}
			break;
		case 'IHAVE':
			$messageid = strtok(" \t");
			if ($messageid === FALSE || strlen($messageid) <= 2 || $messageid[0] != '<' || $messageid[strlen($messageid)-1] == '>') {
				nntp_writeline(STDOUT, '435 Argument error');
				break;
			}
			$messageid = substr($messageid, 1, -1);
			if ($db->evalRow('SELECT `id` FROM `messages` WHERE `messageid` = ?', $messageid) !== FALSE) {
				nntp_writeline(STDOUT, '435 Duplicate');
				break;
			}
			nntp_writeline(STDOUT, '335 Send article to be transferred');
			$lines = nntp_readlines(STDIN);
			try {
				$messageid = nntp_article_store($lines);
				nntp_writeline(STDOUT, '235 Article received <'.$messageid.'>');
			} catch (Exception $ex) {
				nntp_writeline(STDOUT, '437 '.$ex->getMessage());
			}
			break;
		case 'QUIT':
			nntp_writeline(STDOUT, '205 Bye.');
			return;
		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");
}