Add OGP metadata for artworks

routes/artworks.cpp

@@ -9,9 +9,11 @@
 static inline Element generate_user_link(const httplib::Request& req, const Config& config, const Illust& illust);
 static inline Element generate_images(const httplib::Request& req, const Config& config, const Illust& illust);
 static inline Element generate_preview_images(const httplib::Request& req, const Config& config, const Illust& illust);
-static inline std::vector<blankie::html::Node> parse_description_line(const httplib::Request& req, const Config& config, std::string str);
+static inline Nodes parse_description_line(const httplib::Request& req, const Config& config, std::string str);
 static inline Element generate_description(const httplib::Request& req, const Config& config, const std::string& description);
 static inline Element generate_illust_tags(const httplib::Request& req, const Config& config, const Illust& illust);
+static inline std::string generate_description_text(const httplib::Request& req, const Config& config, std::string description);
+static inline Nodes generate_ogp_nodes(const httplib::Request& req, const Config& config, const Illust& illust);
 
 static inline bool is_true(const std::string& str);
 static inline std::string time_to_string(time_t time);
@@ -51,7 +53,7 @@ void artworks_route(const httplib::Request& req, httplib::Response& res, const C
     }
     body.nodes.push_back(generate_illust_tags(req, config, illust));
     body.nodes.push_back(Element("p", {time_to_string(illust.upload_time)}));
-    serve(req, res, config, std::move(illust.title), std::move(body));
+    serve(req, res, config, illust.title, std::move(body), generate_ogp_nodes(req, config, illust));
 }
 
 static inline Element generate_user_link(const httplib::Request& req, const Config& config, const Illust& illust) {
@@ -120,8 +122,8 @@ static inline Element generate_preview_images(const httplib::Request& req, const
     return div;
 }
 
-static inline std::vector<blankie::html::Node> parse_description_line(const httplib::Request& req, const Config& config, std::string str) {
+static inline Nodes parse_description_line(const httplib::Request& req, const Config& config, std::string str) {
-    std::vector<blankie::html::Node> nodes;
+    Nodes nodes;
     std::smatch sm;
 
     while (std::regex_search(str, sm, blankie::murl::full_url_regex)) {
@@ -160,7 +162,7 @@ static inline Element generate_description(const httplib::Request& req, const Co
         if (!p.nodes.empty()) {
             p.nodes.push_back(Element("br"));
         }
-        std::vector<blankie::html::Node> nodes = parse_description_line(req, config, std::move(str));
+        Nodes nodes = parse_description_line(req, config, std::move(str));
         p.nodes.insert(p.nodes.end(), nodes.begin(), nodes.end());
     };
 
@@ -196,6 +198,61 @@ static inline Element generate_illust_tags(const httplib::Request& req, const Co
     return div;
 }
 
+static inline std::string generate_description_text(const httplib::Request& req, const Config& config, std::string description) {
+    std::string new_description;
+    std::smatch sm;
+
+    new_description.reserve(description.size());
+    while (std::regex_search(description, sm, blankie::murl::full_url_regex)) {
+        std::string prefix = sm.prefix();
+        std::string url_str = sm.str(0);
+        std::string suffix = sm.suffix();
+
+        if (prefix.ends_with('(') && url_str.ends_with(')')) {
+            url_str.pop_back();
+            suffix.insert(0, 1, ')');
+        }
+        new_description += std::move(prefix);
+
+        blankie::murl::Url url(std::move(url_str));
+        url_str = url.is_host_equal("pixiv.net") || url.is_host_equal("www.pixiv.net")
+            ? proxy_pixiv_url(req, config, std::move(url))
+            : url.to_string();
+        new_description += std::move(url_str);
+
+        description = std::move(suffix);
+    }
+    new_description += std::move(description);
+
+    return new_description;
+}
+
+static inline Nodes generate_ogp_nodes(const httplib::Request& req, const Config& config, const Illust& illust) {
+    Nodes nodes({
+        Element("meta", {{"property", "og:title"}, {"content", illust.title}}, {}),
+        Element("meta", {{"property", "og:type"}, {"content", "photo"}}, {}),
+        Element("meta", {{"property", "og:site_name"}, {"content", "Pixwhile"}}, {}),
+        Element("meta", {{"property", "og:url"}, {"content", get_origin(req, config) + "/artworks/" + std::to_string(illust.illust_id)}}, {})
+    });
+    if (illust.comment) {
+        nodes.push_back(Element("meta", {{"property", "og:description"}, {"content", generate_description_text(req, config, *illust.comment)}}, {}));
+    }
+
+    // i don't even know what multiple og:images do anymore
+    // https://stackoverflow.com/questions/13424780/facebook-multiple-ogimage-tags-which-is-default
+    nodes.reserve(nodes.size() + illust.images.size() * 3);
+    for (const Images& images : illust.images) {
+        const Image& image = images.thumbnail_or_original();
+        nodes.push_back(Element("meta", {{"property", "og:image"}, {"content", proxy_image_url(config, image.url)}}, {}));
+        if (image.size) {
+            nodes.push_back(Element("meta", {{"property", "og:image:width"}, {"content", std::to_string(image.size->first)}}, {}));
+            nodes.push_back(Element("meta", {{"property", "og:image:height"}, {"content", std::to_string(image.size->second)}}, {}));
+        }
+    }
+
+    return nodes;
+}
+
 static inline bool is_true(const std::string& str) {
     return !str.empty() && str != "0" && str != "false" && str != "no";
 }

routes/tags.cpp

@@ -99,7 +99,7 @@ static inline Element generate_header(const httplib::Request& req, const Config&
 
 static inline Element generate_search_suggestions(const httplib::Request& req, const Config& config,
         const std::vector<std::string>& tags, const std::vector<SearchSuggestion>& search_suggestions, bool open_by_default) {
-    std::vector<blankie::html::Node> ul_nodes;
+    Nodes ul_nodes;
     ul_nodes.reserve(search_suggestions.size());
     for (const SearchSuggestion& search_suggestion : search_suggestions) {
         std::string text = search_suggestion.tag;

servehelper.cpp

@@ -11,20 +11,23 @@ static inline Element generate_illusts_grid(const httplib::Request& req, const C
 static inline Element generate_illusts_grid_item(const httplib::Request& req, const Config& config, const Illust& illust);
 static inline Element generate_illust_badge(const Illust& illust, const std::string& illust_url);
 
-void serve(const httplib::Request& req, httplib::Response& res, const Config& config, std::string title, Element element) {
+void serve(const httplib::Request& req, httplib::Response& res, const Config& config, std::string title, Element element, Nodes extra_head) {
     using namespace std::string_literals;
 
     std::string css_url = get_origin(req, config) + "/style.css";
     res.set_header("Content-Security-Policy", "default-src 'none'; style-src "s + css_url
         + "; img-src https://s.pximg.net " + config.image_proxy_url.get_origin());
 
+    Element head("head", {
+        Element("meta", {{"charset", "utf-8"}}, {}),
+        Element("title", {std::move(title)}),
+        Element("link", {{"rel", "stylesheet"}, {"href", std::move(css_url) + "?v=" + std::to_string(css_hash)}}, {}),
+        Element("meta", {{"name", "viewport"}, {"content", "width=device-width,initial-scale=1"}}, {})
+    });
+    head.nodes.reserve(head.nodes.size() + extra_head.size());
+    head.nodes.insert(head.nodes.end(), extra_head.begin(), extra_head.end());
     std::string html = "<!DOCTYPE html>"s + Element("html", {
-        Element("head", {
+        std::move(head),
-            Element("meta", {{"charset", "utf-8"}}, {}),
-            Element("title", {std::move(title)}),
-            Element("link", {{"rel", "stylesheet"}, {"href", std::move(css_url) + "?v=" + std::to_string(css_hash)}}, {}),
-            Element("meta", {{"name", "viewport"}, {"content", "width=device-width,initial-scale=1"}}, {})
-        }),
         std::move(element)
     }).serialize();
 

servehelper.h

@@ -9,8 +9,10 @@
 struct Config; // forward declaration from config.h
 struct Illusts; // forward declaration from pixivmodels.h
 using Element = blankie::html::Element;
+using Node = blankie::html::Node;
+using Nodes = std::vector<Node>;
 
-void serve(const httplib::Request& req, httplib::Response& res, const Config& config, std::string title, Element element);
+void serve(const httplib::Request& req, httplib::Response& res, const Config& config, std::string title, Element element, Nodes extra_head = {});
 void serve_error(const httplib::Request& req, httplib::Response& res, const Config& config,
         std::string title, std::optional<std::string> subtitle = std::nullopt, std::optional<std::string> info = std::nullopt);
 void serve_redirect(const httplib::Request& req, httplib::Response& res, const Config& config, std::string url);