From 4e1c62ac901d9d4f1a5a103baa8df1319ef8306a Mon Sep 17 00:00:00 2001
From: Kieran <kieran@harkin.me>
Date: Thu, 7 Mar 2024 11:37:16 +0000
Subject: [PATCH] Fix opengraph

---
 .../Controllers/OpenGraphController.cs        | 61 +++++++++++--------
 1 file changed, 37 insertions(+), 24 deletions(-)

diff --git a/NostrServices/Controllers/OpenGraphController.cs b/NostrServices/Controllers/OpenGraphController.cs
index eb83d32..01352b4 100644
--- a/NostrServices/Controllers/OpenGraphController.cs
+++ b/NostrServices/Controllers/OpenGraphController.cs
@@ -14,17 +14,8 @@ namespace NostrServices.Controllers;
 /// Add OpenGraph tags to html documents
 /// </summary>
 [Route("/api/v1/opengraph")]
-public class OpenGraphController : Controller
+public class OpenGraphController(ILogger<OpenGraphController> logger, RedisStore redisStore) : Controller
 {
-    private readonly ILogger<OpenGraphController> _logger;
-    private readonly RedisStore _redisStore;
-
-    public OpenGraphController(ILogger<OpenGraphController> logger, RedisStore redisStore)
-    {
-        _logger = logger;
-        _redisStore = redisStore;
-    }
-
     /// <summary>
     /// Inject opengraph tags into provided html
     /// </summary>
@@ -63,7 +54,7 @@ public class OpenGraphController : Controller
             {
                 if (nid.Hrp is "nevent" or "note" or "naddr")
                 {
-                    var ev = await _redisStore.GetEvent(nid);
+                    var ev = await redisStore.GetEvent(nid);
                     if (ev != default)
                     {
                         var tags = MetaTagsToElements(await GetEventTags(ev));
@@ -75,7 +66,7 @@ public class OpenGraphController : Controller
                 }
                 else if (nid.Hrp is "nprofile" or "npub")
                 {
-                    var profile = await _redisStore.GetProfile(nid.Special);
+                    var profile = await redisStore.GetProfile(nid.Special);
 
                     var meta = await GetProfileMeta(profile);
                     var tags = MetaTagsToElements([
@@ -98,7 +89,7 @@ public class OpenGraphController : Controller
             }
             catch (Exception ex) when (ex is not TaskCanceledException)
             {
-                _logger.LogWarning("Failed to inject event tags: {Message}", ex.ToString());
+                logger.LogWarning("Failed to inject event tags: {Message}", ex.ToString());
             }
         }
 
@@ -109,17 +100,20 @@ public class OpenGraphController : Controller
     {
         var ret = new List<KeyValuePair<string, string>>();
 
-        var profile = await _redisStore.GetProfile(ev.PubKey.ToHex());
+        var profile = await redisStore.GetProfile(ev.PubKey.ToHex());
         var name = profile?.Name ?? "Nostrich";
         switch (ev.Kind)
         {
             case (long)NostrKind.LiveEvent:
             {
-                var host = ev.Tags.FirstOrDefault(a => a.Key == "p" && a.Values[1] == "host")?.Values[0] ?? ev.PubKey.ToHex();
-                var hostProfile = await _redisStore.GetProfile(host);
+                var host = ev.Tags.FirstOrDefault(a => a.Key == "p" && a.Values[^1] == "host")
+                               ?.Values[0] ??
+                           ev.PubKey.ToHex();
+                var hostProfile = await redisStore.GetProfile(host);
                 var hostName = hostProfile?.Name ?? profile?.Name ?? "Nostrich";
                 var stream = ev.GetFirstTagValue("streaming") ?? ev.GetFirstTagValue("recording") ?? "";
-                var image = ev.GetFirstTagValue("image") ?? hostProfile?.Picture ?? $"https://robohash.v0l.io/{ev.PubKey.ToHex()}.png";
+                var image = ev.GetFirstTagValue("image") ??
+                            hostProfile?.Picture ?? $"https://robohash.v0l.io/{ev.PubKey.ToHex()}.png";
                 ret.AddRange(new KeyValuePair<string, string>[]
                 {
                     new("og:type", "video.other"),
@@ -145,7 +139,8 @@ public class OpenGraphController : Controller
             case 1_313: // stream clip
             {
                 var stream = ev.GetFirstTagValue("r")!;
-                var image = ev.GetFirstTagValue("image") ?? profile?.Picture ?? $"https://robohash.v0l.io/{ev.PubKey.ToHex()}.png";
+                var image = ev.GetFirstTagValue("image") ??
+                            profile?.Picture ?? $"https://robohash.v0l.io/{ev.PubKey.ToHex()}.png";
                 ret.AddRange(new KeyValuePair<string, string>[]
                 {
                     new("og:type", "video.other"),
@@ -212,15 +207,24 @@ public class OpenGraphController : Controller
 
         foreach (var ex in tags)
         {
-            var tag = doc.CreateElement(ex.Element);
+            IElement tag = doc.Head?.Children.FirstOrDefault(a =>
+            {
+                if (ex.Element == "meta")
+                {
+                    var metaPropertyA = a.Attributes.FirstOrDefault(b => b.Name == "property");
+                    var metaPropertyB = ex.Attributes.FirstOrDefault(b => b is { Key: "property" });
+                    return metaPropertyA?.Value == metaPropertyB.Value;
+                }
+
+                return false;
+            }) ?? AddNewTag(ex);
+
             foreach (var attr in ex.Attributes)
             {
                 tag.SetAttribute(attr.Key, attr.Value);
             }
 
-            doc.Head?.AppendChild(tag);
-
-            var isOgTitle = ex.Attributes.Any(a => a is {Key: "property", Value: "og:title"});
+            var isOgTitle = ex.Attributes.Any(a => a is { Key: "property", Value: "og:title" });
             if (isOgTitle && doc.Head != default)
             {
                 var titleTag = doc.Head.QuerySelector("title");
@@ -238,7 +242,7 @@ public class OpenGraphController : Controller
                 }
             }
 
-            var isOgDesc = ex.Attributes.Any(a => a is {Key: "property", Value: "og:description"});
+            var isOgDesc = ex.Attributes.Any(a => a is { Key: "property", Value: "og:description" });
             if (isOgDesc && doc.Head != default)
             {
                 var ogDesc = ex.Attributes.FirstOrDefault(a => a.Key is "content");
@@ -256,6 +260,15 @@ public class OpenGraphController : Controller
                     descriptionTag.SetAttribute("content", ogDesc.Value);
                 }
             }
+
+            continue;
+
+            IElement AddNewTag(HeadElement he)
+            {
+                var tx = doc!.CreateElement(he.Element);
+                doc.Head?.AppendChild(tx);
+                return tx;
+            }
         }
 
         return doc;
@@ -295,4 +308,4 @@ class CachedMeta
 
     [ProtoMember(5)]
     public CompactEvent? Event { get; init; }
-}
+}
\ No newline at end of file