<?php namespace HashOver;

// Copyright (C) 2010-2021 Jacob Barkdull
// This file is part of HashOver.
//
// HashOver is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as
// published by the Free Software Foundation, either version 3 of the
// License, or (at your option) any later version.
//
// HashOver is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with HashOver. If not, see <http://www.gnu.org/licenses/>.


// Tell browser this is XML/RSS
header ('Content-Type: application/xml; charset=utf-8');

// Change to the HashOver directory
chdir (realpath ('../'));

// Do some standard HashOver setup work
require ('backend/nocache-headers.php');
require (
'backend/standard-setup.php');

// Setup class autoloader
setup_autoloader (function ($error) {
echo '<?xml version="1.0" encoding="UTF-8"?>', PHP_EOL;
echo '<error>', $error, '</error>';
});

// Parses comment into RSS item
function parse_comments (&$metadata, &$comment, &$rss, &$xml, &$hashover)
{
// Skip deleted/unmoderated comments
if (isset ($comment['notice'])) {
return;
}

// Encode HTML entities
$comment['body'] = htmlentities ($comment['body'], ENT_COMPAT, 'UTF-8', true);

// Decode HTML entities
$comment['body'] = html_entity_decode ($comment['body'], ENT_COMPAT, 'UTF-8');

// Remove [img] tags
$comment['body'] = preg_replace ('/\[(img|\/img)\]/iS', '', $comment['body']);

// Parse comment as markdown
$comment['body'] = $hashover->markdown->parseMarkdown ($comment['body']);

// Convert <code> tags to <pre> tags
$comment['body'] = preg_replace ('/(<|<\/)code>/iS', '\\1pre>', $comment['body']);

// Get name from comment or use configured default
$name = Misc::getArrayItem ($comment, 'name') ?: $hashover->setup->defaultName;

// Create item element
$item = $xml->createElement ('item');

// Start item summary title with user's name
$title = $name . ' : ';

// Strip HTML tags from comment and remove all newlines
$single_comment = str_replace (PHP_EOL, ' ', strip_tags ($comment['body']));

// Check if comment is more than 40 characters long
if (mb_strlen ($single_comment) > 40) {
// If so, add 40 characters of comment to summary title
$title .= mb_substr ($single_comment, 0, 40) . '...';
} else {
// If not, add comment to summary title as-is
$title .= $single_comment;
}

// Create item title element
$item_title = $xml->createElement ('title');
$item_title_value = $xml->createTextNode (html_entity_decode ($title, ENT_COMPAT, 'UTF-8'));
$item_title->appendChild ($item_title_value);

// Add item title element to item element
$item->appendChild ($item_title);

// Create item name element
$item_name = $xml->createElement ('name');
$item_name_value = $xml->createTextNode (html_entity_decode ($name, ENT_COMPAT, 'UTF-8'));
$item_name->appendChild ($item_name_value);

// Add item name element to item element
$item->appendChild ($item_name);

// URL regular expression
$url_regex = '/((http|https|ftp):\/\/[a-z0-9-@:%_\+.~#?&\/=]+) {0,}/iS';

// Add HTML anchor tag to URLs (hyperlinks)
$comment['body'] = preg_replace ($url_regex, '<a href="\\1" target="_blank">\\1</a>', $comment['body']);

// Replace newlines with break tags
$comment['body'] = str_replace (PHP_EOL, '<br>', $comment['body']);

// Create item description element
$item_description = $xml->createElement ('description');
$item_description_value = $xml->createTextNode ($comment['body']);
$item_description->appendChild ($item_description_value);

// Add item description element to item element
$item->appendChild ($item_description);

// Create item avatar element
$item_avatar = $xml->createElement ('avatar');
$item_avatar_value = $xml->createTextNode ($comment['avatar']);
$item_avatar->appendChild ($item_avatar_value);

// Add item avatar element to item element
$item->appendChild ($item_avatar);

// Check if likes are enabled
if (!empty ($comment['likes'])) {
// If so, create item likes element
$item_likes = $xml->createElement ('likes');
$item_likes_value = $xml->createTextNode ($comment['likes']);
$item_likes->appendChild ($item_likes_value);

// Add item likes element to item element
$item->appendChild ($item_likes);
}

// Check if dislikes are enabled
if ($hashover->setup->allowsDislikes === true) {
// If so, check if comment has any dislikes
if (!empty ($comment['dislikes'])) {
// If so, create dislikes item element
$item_dislikes = $xml->createElement ('dislikes');
$item_dislikes_value = $xml->createTextNode ($comment['dislikes']);
$item_dislikes->appendChild ($item_dislikes_value);

// Add dislikes item element to item element
$item->appendChild ($item_dislikes);
}
}

// Create item publication date element
$item_pubDate = $xml->createElement ('pubDate');
$item_pubDate_value = date (DATE_RSS, $comment['timestamp']);
$item_pubDate_node = $xml->createTextNode ($item_pubDate_value);
$item_pubDate->appendChild ($item_pubDate_node);

// Add item pubDate element to item element
$item->appendChild ($item_pubDate);

// URL to comment for item guide and link elements
$item_permalink_url = $metadata['url'] . '#' . $comment['permalink'];

// Create item guide element
$item_guid = $xml->createElement ('guid');
$item_guid_value = $xml->createTextNode ($item_permalink_url);
$item_guid->appendChild ($item_guid_value);

// Add item guide element to item element
$item->appendChild ($item_guid);

// Create item link element
$item_link = $xml->createElement ('link');
$item_link_value = $xml->createTextNode ($item_permalink_url);
$item_link->appendChild ($item_link_value);

// Add item link element to item element
$item->appendChild ($item_link);

// Add item element to main RSS element
$rss->appendChild ($item);

// Recursively parse replies
if (!empty ($comment['replies'])) {
foreach ($comment['replies'] as $reply) {
parse_comments ($metadata, $reply, $rss, $xml, $hashover);
}
}
}

// Creates RSS feed
function create_rss (&$hashover)
{
// Shorter variable name
$thread = $hashover->setup->threadName;

// Attempt to read page information metadata
$metadata = $hashover->thread->data->readMeta ('page-info', $thread);

// Check if metadata read successfully
if ($metadata !== false) {
// If so, set page URL blank if it's missing from the metadata
if (!isset ($metadata['url'])) {
$metadata['url'] = '';
}

// And set page title to "Untitled" if it's missing from the metadata
if (!isset ($metadata['title'])) {
$metadata['title'] = $hashover->locale->text['untitled'];
}
} else {
// If not, set default metadata information
$metadata = array (
'url' => '',
'title' => $hashover->locale->text['untitled']
);
}

// Create new DOM document.
$xml = new \DOMDocument ('1.0', 'UTF-8');
$xml->preserveWhiteSpace = false;
$xml->formatOutput = true;

// Create main RSS element
$rss = $xml->createElement ('rss');
$rss->setAttribute ('version', '2.0');
$rss->setAttribute ('xmlns:dc', 'http://purl.org/dc/elements/1.1/');
$rss->setAttribute ('xmlns:content', 'http://purl.org/rss/1.0/modules/content/');
$rss->setAttribute ('xmlns:atom', 'http://www.w3.org/2005/Atom');

// Create channel element
$channel = $xml->createElement ('channel');

// Create channel title element
$title = $xml->createElement ('title');
$title_value = $xml->createTextNode (html_entity_decode ($metadata['title'], ENT_COMPAT, 'UTF-8'));
$title->appendChild ($title_value);

// Add channel title to channel element
$channel->appendChild ($title);

// Create channel link element
$link = $xml->createElement ('link');
$link_value = $xml->createTextNode (html_entity_decode ($metadata['url'], ENT_COMPAT, 'UTF-8'));
$link->appendChild ($link_value);

// Add channel link to channel element
$channel->appendChild ($link);

// Check if there is more than one comment
if ($hashover->thread->totalCount !== 1) {
// If so, use "X Comments" locale string
$showing_comments_locale = $hashover->locale->text['showing-comments'];
} else {
// If not, use "X Comment" locale string
$showing_comments_locale = $hashover->locale->text['showing-comment'];
}

// Create channel description element
$description = $xml->createElement ('description');
$count_locale = sprintf ($showing_comments_locale, $hashover->thread->totalCount - 1);
$description_value = $xml->createTextNode ($count_locale);
$description->appendChild ($description_value);

// Add channel description to channel element
$channel->appendChild ($description);

// Create channel atom link element
$atom_link = $xml->createElement ('atom:link');
$atom_url = $hashover->setup->domain . $_SERVER['PHP_SELF'] . '?url=' . urlencode ($metadata['url']);
$atom_link->setAttribute ('href', 'http://' . $atom_url);
$atom_link->setAttribute ('rel', 'self');

// Add channel atom link to channel element
$channel->appendChild ($atom_link);

// Create channel language element
$language = $xml->createElement ('language');
$language_value = $xml->createTextNode ('en-us');
$language->appendChild ($language_value);

// Add channel language to channel element
$channel->appendChild ($language);

// Create channel ttl element
$ttl = $xml->createElement ('ttl');
$ttl_value = $xml->createTextNode ('40');
$ttl->appendChild ($ttl_value);

// Add channel ttl to channel element
$channel->appendChild ($ttl);

// Add channel element to main RSS element
$rss->appendChild ($channel);

// Add item element to main RSS element
foreach ($hashover->comments['primary'] as $comment) {
parse_comments ($metadata, $comment, $rss, $xml, $hashover);
}

// Add main RSS element to XML
$xml->appendChild ($rss);

// Return RSS XML
echo preg_replace_callback ('/^(\s+)/m', function ($spaces) {
return str_repeat ("\t", mb_strlen ($spaces[1]) / 2);
}, $xml->saveXML ());

// Return statistics
echo $hashover->statistics->executionEnd ('php');
}

try {
// Instantiate HashOver class
$hashover = new \HashOver ('rss');

// Throw exception if API is disabled
$hashover->setup->apiCheck ('rss');

// Enable remote access
$hashover->setup->enablesRemoteAccess (true);

// Set page URL from GET data
$hashover->setup->setPageURL ('request');

// Initiate comment processing
$hashover->initiate ();

// Parse primary comments into usable data
$hashover->parsePrimary ();

// Attempt to get sorting method
$method = $hashover->setup->getRequest ('sorting', 'by-date');

// Sort comments by sorting method
$hashover->sortPrimary ($method);

// Create RSS feed
create_rss ($hashover);

} catch (
\Exception $error) {
echo Misc::displayException ($error, 'rss');
}