From f49564db23e6b60aad396752be0e4d9de109b61e Mon Sep 17 00:00:00 2001
From: joyqi <magike.net@gmail.com>
Date: Wed, 6 Apr 2022 18:26:15 +0800
Subject: [PATCH] Add feed widget

---
 var/Widget/Archive.php |   3 +-
 var/Widget/Feed.php    | 129 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 131 insertions(+), 1 deletion(-)
 create mode 100644 var/Widget/Feed.php

diff --git a/var/Widget/Archive.php b/var/Widget/Archive.php
index 6f70b23e..540f6701 100644
--- a/var/Widget/Archive.php
+++ b/var/Widget/Archive.php
@@ -1012,7 +1012,8 @@ class Archive extends Contents
 
             $linkText = empty($title) ? $content['title'] : $title;
             $linkClass = empty($tagClass) ? '' : 'class="' . $tagClass . '" ';
-            $link = '<a ' . $linkClass . 'href="' . $content['permalink'] . '" title="' . $content['title'] . '">' . $linkText . '</a>';
+            $link = '<a ' . $linkClass . 'href="' . $content['permalink']
+                . '" title="' . $content['title'] . '">' . $linkText . '</a>';
 
             printf($format, $link);
         } else {
diff --git a/var/Widget/Feed.php b/var/Widget/Feed.php
new file mode 100644
index 00000000..a6d22884
--- /dev/null
+++ b/var/Widget/Feed.php
@@ -0,0 +1,129 @@
+<?php
+
+namespace Widget;
+
+use Exception;
+use Typecho\Common;
+use Typecho\Config;
+use Typecho\Router;
+use Typecho\Widget\Exception as WidgetException;
+use Widget\Base\Contents;
+use Typecho\Feed as FeedGenerator;
+
+if (!defined('__TYPECHO_ROOT_DIR__')) {
+    exit;
+}
+
+/**
+ * Feed handler
+ */
+class Feed extends Contents
+{
+    /**
+     * @param Config $parameter
+     * @throws Exception
+     */
+    protected function initParameter(Config $parameter)
+    {
+        $parameter->setDefault([
+            'pageSize'       => 10,
+        ]);
+    }
+
+    /**
+     * @throws Exception
+     */
+    public function execute()
+    {
+        $feedPath = $this->request->feed;
+        $feedType = FeedGenerator::RSS2;
+        $feedContentType = 'application/rss+xml';
+        $currentFeedUrl = $this->options->feedUrl;
+        $isComments = false;
+
+        /** 判断聚合类型 */
+        switch (true) {
+            case preg_match("/^\/rss(\/|$)/", $feedPath):
+                /** 如果是RSS1标准 */
+                $feedPath = substr($feedPath, 4);
+                $feedType = FeedGenerator::RSS1;
+                $currentFeedUrl = $this->options->feedRssUrl;
+                $feedContentType = 'application/rdf+xml';
+                break;
+            case preg_match("/^\/atom(\/|$)/", $feedPath):
+                /** 如果是ATOM标准 */
+                $feedPath = substr($feedPath, 5);
+                $feedType = FeedGenerator::ATOM1;
+                $currentFeedUrl = $this->options->feedAtomUrl;
+                $feedContentType = 'application/atom+xml';
+                break;
+            default:
+                break;
+        }
+
+        $feed = new FeedGenerator(
+            Common::VERSION,
+            $feedType,
+            $this->options->charset,
+            _t('zh-CN')
+        );
+
+        if (preg_match("/^\/comments\/?$/", $feedPath)) {
+            $isComments = true;
+            $currentFeedUrl = Common::url('/comments/', $currentFeedUrl);
+            $feed->setBaseUrl($this->options->siteUrl);
+            $feed->setSubTitle($this->options->description);
+        } else {
+            $archive = Router::match($feedPath, [
+                'pageSize' => $this->parameter->pageSize,
+                'isFeed'   => true
+            ]);
+
+            if (!($archive instanceof Archive)) {
+                throw new WidgetException(_t('聚合页不存在'), 404);
+            }
+
+            $path = parse_url($archive->getArchiveUrl(), PHP_URL_PATH);
+            $currentFeedUrl = Common::url($path, $currentFeedUrl);
+            $feed->setBaseUrl($archive->getArchiveUrl());
+            $feed->setSubTitle($archive->getDescription());
+        }
+
+        $this->checkPermalink($currentFeedUrl);
+        $feed->setFeedUrl($currentFeedUrl);
+        $this->render($feed, $feedContentType, $isComments, $archive ?? null);
+    }
+
+    /**
+     * @param FeedGenerator $feed
+     * @param string $contentType
+     * @param bool $isComments
+     * @param Archive|null $archive
+     */
+    public function render(
+        FeedGenerator $feed,
+        string $contentType,
+        bool $isComments,
+        ?Archive $archive
+    ) {
+        if ($isComments || $archive->is('single')) {
+            $feed->setTitle(_t(
+                '%s 的评论',
+                $this->options->title . ($isComments ? '' : ' - ' . $archive->getArchiveTitle())
+            ));
+        } else {
+            $feed->setTitle($this->options->title
+                . ($archive->getArchiveTitle() ? ' - ' . $archive->getArchiveTitle() : ''));
+        }
+    }
+
+    /**
+     * @param string $feedUrl
+     */
+    private function checkPermalink(string $feedUrl)
+    {
+        if ($feedUrl != $this->request->getRequestUri()) {
+            $this->response->redirect($feedUrl, true);
+        }
+    }
+}