From b302ce23bd61b28f3a456596f82cd035c158ad51 Mon Sep 17 00:00:00 2001
From: Ben Klein <robobenklein@gmail.com>
Date: Sat, 10 Jul 2021 17:17:08 -0400
Subject: [PATCH] client/lua: stricter matches and home tags

---
 client/metatags.lua | 41 +++++++++++++++++++++++++++++++++++------
 1 file changed, 35 insertions(+), 6 deletions(-)

diff --git a/client/metatags.lua b/client/metatags.lua
index 92dcae19..9274bf27 100644
--- a/client/metatags.lua
+++ b/client/metatags.lua
@@ -41,7 +41,29 @@ end
 add_meta_tag("og:site_name", server_info.config.name)
 add_meta_tag("og:url", ngx.var.external_host_url .. ngx.var.request_uri_path)
 
-if ngx.var.request_uri_path:match('^/post') then -- Post metadata
+if ngx.var.request_uri_path:match('^/$') then -- Site root
+  add_meta_tag("og:title", server_info.config.name)
+  add_meta_tag("twitter:title", server_info.config.name)
+  -- if there's a featured post, let's use that as the image
+  if server_info.featuredPost then
+    local post_info = server_info.featuredPost
+    -- NOTE this is different from the normal Post tags,
+    -- notably we avoid setting the article type, author, time, etc
+    local og_media_prefix
+    if post_info.type == "image" then
+      og_media_prefix = "og:image"
+      add_meta_tag("twitter:card", "summary_large_image")
+      add_meta_tag("twitter:image", ngx.var.external_host_url .. '/' .. post_info.contentUrl)
+    elseif post_info.type == "video" then
+      og_media_prefix = "og:video"
+      -- some sites don't preview video, so at least provide a thumbnail
+      add_meta_tag("og:image", ngx.var.external_host_url .. '/' .. post_info.thumbnailUrl)
+    end
+    add_meta_tag(og_media_prefix..":url", ngx.var.external_host_url .. '/' .. post_info.contentUrl)
+    add_meta_tag(og_media_prefix..":width", post_info.canvasWidth)
+    add_meta_tag(og_media_prefix..":height", post_info.canvasHeight)
+  end
+elseif ngx.var.request_uri_path:match('^/post/([0-9]+)/?$') then -- Post metadata
   -- check if posts are accessible to anonymous users:
   if server_info.config.privileges["posts:view"] == "anonymous" then
     add_meta_tag("og:type", "article")
@@ -70,15 +92,22 @@ if ngx.var.request_uri_path:match('^/post') then -- Post metadata
     -- no permission to retrieve post data
     add_meta_tag("og:title", server_info.config.name .. " - Login required")
   end
-elseif ngx.var.request_uri_path:match('^/user/(.*)$') then -- User metadata
-  local username = ngx.var.request_uri_path:match('^/user/(.*)/?$')
-  add_meta_tag("og:title", server_info.config.name .. " - User " .. username)
+elseif ngx.var.request_uri_path:match('^/user/([^/]+)/?$') then -- User metadata
+  local username = ngx.var.request_uri_path:match('^/user/([^/]+)/?$')
+  add_meta_tag("og:title", server_info.config.name .. " - " .. username)
+  add_meta_tag("og:type", "profile")
   -- check for permission to access user profiles
   if server_info.config.privileges["users:view"] == "anonymous" then
     local user_info = cjson.decode((ngx.location.capture("/_internal_api/"..username)).body)
-    -- TODO
+    add_meta_tag("profile:username", user_info.name)
+    local avatar_url = user_info.avatarUrl
+    if avatar_url:match("^https?://") then
+      add_meta_tag("og:image", avatar_url)
+    else
+      add_meta_tag("og:image", ngx.var.external_host_url .. '/' .. avatar_url)
+    end
   else
-    -- TODO
+    -- no permission to view user data
   end
 end