<?php
/**
*
* This file is part of the phpBB Forum Software package.
*
* @copyright (c) phpBB Limited <https://www.phpbb.com>
* @license GNU General Public License, version 2 (GPL-2.0)
*
* For full copyright and license information, please see
* the docs/CREDITS.txt file.
*
*/

/**
* @ignore
*/
define('IN_PHPBB', true);
$phpbb_root_path = (defined('PHPBB_ROOT_PATH')) ? PHPBB_ROOT_PATH : './';
$phpEx = substr(strrchr(__FILE__, '.'), 1);
include($phpbb_root_path . 'common.' . $phpEx);
include($phpbb_root_path . 'includes/functions_display.' . $phpEx);
include($phpbb_root_path . 'includes/bbcode.' . $phpEx);
include($phpbb_root_path . 'includes/functions_user.' . $phpEx);

// Start session management
$user->session_begin();
$auth->acl($user->data);

// Initial var setup
$forum_id	= request_var('f', 0);
$topic_id	= request_var('t', 0);
$post_id	= request_var('p', 0);
$voted_id	= request_var('vote_id', array('' => 0));

$voted_id = (sizeof($voted_id) > 1) ? array_unique($voted_id) : $voted_id;


$start		= request_var('start', 0);
$view		= request_var('view', '');

$default_sort_days	= (!empty($user->data['user_post_show_days'])) ? $user->data['user_post_show_days'] : 0;
$default_sort_key	= (!empty($user->data['user_post_sortby_type'])) ? $user->data['user_post_sortby_type'] : 't';
$default_sort_dir	= (!empty($user->data['user_post_sortby_dir'])) ? $user->data['user_post_sortby_dir'] : 'a';

$sort_days	= request_var('st', $default_sort_days);
$sort_key	= request_var('sk', $default_sort_key);
$sort_dir	= request_var('sd', $default_sort_dir);

$update		= request_var('update', false);

$pagination = $phpbb_container->get('pagination');

$s_can_vote = false;
/**
* @todo normalize?
*/
$hilit_words	= request_var('hilit', '', true);

// Do we have a topic or post id?
if (!$topic_id && !$post_id)
{
	trigger_error('NO_TOPIC');
}

$phpbb_content_visibility = $phpbb_container->get('content.visibility');

// Find topic id if user requested a newer or older topic
if ($view && !$post_id)
{
	if (!$forum_id)
	{
		$sql = 'SELECT forum_id
			FROM ' . TOPICS_TABLE . "
			WHERE topic_id = $topic_id";
		$result = $db->sql_query($sql);
		$forum_id = (int) $db->sql_fetchfield('forum_id');
		$db->sql_freeresult($result);

		if (!$forum_id)
		{
			trigger_error('NO_TOPIC');
		}
	}

	if ($view == 'unread')
	{
		// Get topic tracking info
		$topic_tracking_info = get_complete_topic_tracking($forum_id, $topic_id);
		$topic_last_read = (isset($topic_tracking_info[$topic_id])) ? $topic_tracking_info[$topic_id] : 0;

		$sql = 'SELECT post_id, topic_id, forum_id
			FROM ' . POSTS_TABLE . "
			WHERE topic_id = $topic_id
				AND " . $phpbb_content_visibility->get_visibility_sql('post', $forum_id) . "
				AND post_time > $topic_last_read
				AND forum_id = $forum_id
			ORDER BY post_time ASC, post_id ASC";
		$result = $db->sql_query_limit($sql, 1);
		$row = $db->sql_fetchrow($result);
		$db->sql_freeresult($result);

		if (!$row)
		{
			$sql = 'SELECT topic_last_post_id as post_id, topic_id, forum_id
				FROM ' . TOPICS_TABLE . '
				WHERE topic_id = ' . $topic_id;
			$result = $db->sql_query($sql);
			$row = $db->sql_fetchrow($result);
			$db->sql_freeresult($result);
		}

		if (!$row)
		{
			// Setup user environment so we can process lang string
			$user->setup('viewtopic');

			trigger_error('NO_TOPIC');
		}

		$post_id = $row['post_id'];
		$topic_id = $row['topic_id'];
	}
	else if ($view == 'next' || $view == 'previous')
	{
		$sql_condition = ($view == 'next') ? '>' : '<';
		$sql_ordering = ($view == 'next') ? 'ASC' : 'DESC';

		$sql = 'SELECT forum_id, topic_last_post_time
			FROM ' . TOPICS_TABLE . '
			WHERE topic_id = ' . $topic_id;
		$result = $db->sql_query($sql);
		$row = $db->sql_fetchrow($result);
		$db->sql_freeresult($result);

		if (!$row)
		{
			$user->setup('viewtopic');
			// OK, the topic doesn't exist. This error message is not helpful, but technically correct.
			trigger_error(($view == 'next') ? 'NO_NEWER_TOPICS' : 'NO_OLDER_TOPICS');
		}
		else
		{
			$sql = 'SELECT topic_id, forum_id
				FROM ' . TOPICS_TABLE . '
				WHERE forum_id = ' . $row['forum_id'] . "
					AND topic_moved_id = 0
					AND topic_last_post_time $sql_condition {$row['topic_last_post_time']}
					AND " . $phpbb_content_visibility->get_visibility_sql('topic', $row['forum_id']) . "
				ORDER BY topic_last_post_time $sql_ordering, topic_last_post_id $sql_ordering";
			$result = $db->sql_query_limit($sql, 1);
			$row = $db->sql_fetchrow($result);
			$db->sql_freeresult($result);

			if (!$row)
			{
				$sql = 'SELECT forum_style
					FROM ' . FORUMS_TABLE . "
					WHERE forum_id = $forum_id";
				$result = $db->sql_query($sql);
				$forum_style = (int) $db->sql_fetchfield('forum_style');
				$db->sql_freeresult($result);

				$user->setup('viewtopic', $forum_style);
				trigger_error(($view == 'next') ? 'NO_NEWER_TOPICS' : 'NO_OLDER_TOPICS');
			}
			else
			{
				$topic_id = $row['topic_id'];
				$forum_id = $row['forum_id'];
			}
		}
	}

	if (isset($row) && $row['forum_id'])
	{
		$forum_id = $row['forum_id'];
	}
}

// This rather complex gaggle of code handles querying for topics but
// also allows for direct linking to a post (and the calculation of which
// page the post is on and the correct display of viewtopic)
$sql_array = array(
	'SELECT'	=> 't.*, f.*',

	'FROM'		=> array(FORUMS_TABLE => 'f'),
);

// The FROM-Order is quite important here, else t.* columns can not be correctly bound.
if ($post_id)
{
	$sql_array['SELECT'] .= ', p.post_visibility, p.post_time, p.post_id';
	$sql_array['FROM'][POSTS_TABLE] = 'p';
}

// Topics table need to be the last in the chain
$sql_array['FROM'][TOPICS_TABLE] = 't';

if ($user->data['is_registered'])
{
	$sql_array['SELECT'] .= ', tw.notify_status';
	$sql_array['LEFT_JOIN'] = array();

	$sql_array['LEFT_JOIN'][] = array(
		'FROM'	=> array(TOPICS_WATCH_TABLE => 'tw'),
		'ON'	=> 'tw.user_id = ' . $user->data['user_id'] . ' AND t.topic_id = tw.topic_id'
	);

	if ($config['allow_bookmarks'])
	{
		$sql_array['SELECT'] .= ', bm.topic_id as bookmarked';
		$sql_array['LEFT_JOIN'][] = array(
			'FROM'	=> array(BOOKMARKS_TABLE => 'bm'),
			'ON'	=> 'bm.user_id = ' . $user->data['user_id'] . ' AND t.topic_id = bm.topic_id'
		);
	}

	if ($config['load_db_lastread'])
	{
		$sql_array['SELECT'] .= ', tt.mark_time, ft.mark_time as forum_mark_time';

		$sql_array['LEFT_JOIN'][] = array(
			'FROM'	=> array(TOPICS_TRACK_TABLE => 'tt'),
			'ON'	=> 'tt.user_id = ' . $user->data['user_id'] . ' AND t.topic_id = tt.topic_id'
		);

		$sql_array['LEFT_JOIN'][] = array(
			'FROM'	=> array(FORUMS_TRACK_TABLE => 'ft'),
			'ON'	=> 'ft.user_id = ' . $user->data['user_id'] . ' AND t.forum_id = ft.forum_id'
		);
	}
}

if (!$post_id)
{
	$sql_array['WHERE'] = "t.topic_id = $topic_id";
}
else
{
	$sql_array['WHERE'] = "p.post_id = $post_id AND t.topic_id = p.topic_id";
}

$sql_array['WHERE'] .= ' AND f.forum_id = t.forum_id';

$sql = $db->sql_build_query('SELECT', $sql_array);
$result = $db->sql_query($sql);
$topic_data = $db->sql_fetchrow($result);
$db->sql_freeresult($result);

// link to unapproved post or incorrect link
if (!$topic_data)
{
	// If post_id was submitted, we try at least to display the topic as a last resort...
	if ($post_id && $topic_id)
	{
		redirect(append_sid("{$phpbb_root_path}viewtopic.$phpEx", "t=$topic_id" . (($forum_id) ? "&amp;f=$forum_id" : '')));
	}

	trigger_error('NO_TOPIC');
}

$forum_id = (int) $topic_data['forum_id'];

// Now we know the forum_id and can check the permissions
if ($topic_data['topic_visibility'] != ITEM_APPROVED && !$auth->acl_get('m_approve', $forum_id))
{
	trigger_error('NO_TOPIC');
}

// This is for determining where we are (page)
if ($post_id)
{
	// are we where we are supposed to be?
	if (($topic_data['post_visibility'] == ITEM_UNAPPROVED || $topic_data['post_visibility'] == ITEM_REAPPROVE) && !$auth->acl_get('m_approve', $topic_data['forum_id']))
	{
		// If post_id was submitted, we try at least to display the topic as a last resort...
		if ($topic_id)
		{
			redirect(append_sid("{$phpbb_root_path}viewtopic.$phpEx", "t=$topic_id" . (($forum_id) ? "&amp;f=$forum_id" : '')));
		}

		trigger_error('NO_TOPIC');
	}
	if ($post_id == $topic_data['topic_first_post_id'] || $post_id == $topic_data['topic_last_post_id'])
	{
		$check_sort = ($post_id == $topic_data['topic_first_post_id']) ? 'd' : 'a';

		if ($sort_dir == $check_sort)
		{
			$topic_data['prev_posts'] = $phpbb_content_visibility->get_count('topic_posts', $topic_data, $forum_id) - 1;
		}
		else
		{
			$topic_data['prev_posts'] = 0;
		}
	}
	else
	{
		$sql = 'SELECT COUNT(p.post_id) AS prev_posts
			FROM ' . POSTS_TABLE . " p
			WHERE p.topic_id = {$topic_data['topic_id']}
				AND " . $phpbb_content_visibility->get_visibility_sql('post', $forum_id, 'p.');

		if ($sort_dir == 'd')
		{
			$sql .= " AND (p.post_time > {$topic_data['post_time']} OR (p.post_time = {$topic_data['post_time']} AND p.post_id >= {$topic_data['post_id']}))";
		}
		else
		{
			$sql .= " AND (p.post_time < {$topic_data['post_time']} OR (p.post_time = {$topic_data['post_time']} AND p.post_id <= {$topic_data['post_id']}))";
		}

		$result = $db->sql_query($sql);
		$row = $db->sql_fetchrow($result);
		$db->sql_freeresult($result);

		$topic_data['prev_posts'] = $row['prev_posts'] - 1;
	}
}

$topic_id = (int) $topic_data['topic_id'];
$topic_replies = $phpbb_content_visibility->get_count('topic_posts', $topic_data, $forum_id) - 1;

// Check sticky/announcement time limit
if (($topic_data['topic_type'] == POST_STICKY || $topic_data['topic_type'] == POST_ANNOUNCE) && $topic_data['topic_time_limit'] && ($topic_data['topic_time'] + $topic_data['topic_time_limit']) < time())
{
	$sql = 'UPDATE ' . TOPICS_TABLE . '
		SET topic_type = ' . POST_NORMAL . ', topic_time_limit = 0
		WHERE topic_id = ' . $topic_id;
	$db->sql_query($sql);

	$topic_data['topic_type'] = POST_NORMAL;
	$topic_data['topic_time_limit'] = 0;
}

// Setup look and feel
$user->setup('viewtopic', $topic_data['forum_style']);

$overrides_f_read_check = false;
$overrides_forum_password_check = false;
$topic_tracking_info = isset($topic_tracking_info) ? $topic_tracking_info : null;

/**
* Event to apply extra permissions and to override original phpBB's f_read permission and forum password check
* on viewtopic access
*
* @event core.viewtopic_before_f_read_check
* @var	int		forum_id						The forum id from where the topic belongs
* @var	int		topic_id						The id of the topic the user tries to access