From ae60311e856700b9cce538f4324c298ac3f3e7e1 Mon Sep 17 00:00:00 2001
From: Wyatt Johnson <wyattjoh@gmail.com>
Date: Sat, 22 Sep 2018 00:45:48 -0600
Subject: [PATCH] feat: added root parent edge

---
 .../server/graph/tenant/resolvers/comment.ts  | 25 +++++++++++++++++++
 .../server/graph/tenant/schema/schema.graphql |  5 ++++
 2 files changed, 30 insertions(+)

diff --git a/src/core/server/graph/tenant/resolvers/comment.ts b/src/core/server/graph/tenant/resolvers/comment.ts
index 8690c5cb4..9272a294c 100644
--- a/src/core/server/graph/tenant/resolvers/comment.ts
+++ b/src/core/server/graph/tenant/resolvers/comment.ts
@@ -24,6 +24,31 @@ const Comment: GQLCommentTypeResolver<Comment> = {
   parentCount: comment =>
     comment.parent_id ? comment.grandparent_ids.length + 1 : 0,
   replyCount: comment => comment.child_ids.length,
+  rootParent: (comment, input, ctx, info) => {
+    // If there isn't a parent, then return nothing!
+    if (!comment.parent_id) {
+      return null;
+    }
+
+    // rootParentID is the root parent id for a given comment.
+    const rootParentID =
+      comment.grandparent_ids.length > 0
+        ? comment.grandparent_ids[0]
+        : comment.parent_id;
+
+    // Get the field names of the fields being requested, if it's only the ID,
+    // we have that, so no need to make a database request.
+    const fields = getRequestedFields<GQLComment>(info);
+    if (fields.length === 1 && fields[0] === "id") {
+      return {
+        id: rootParentID,
+      };
+    }
+
+    // We want more than the ID! Get the comment!
+    // TODO: (wyattjoh) if the parent and the parents (containing the parent) are requested, the parent comment is retrieved from the database twice. Investigate ways of reducing i/o.
+    return ctx.loaders.Comments.comment.load(rootParentID);
+  },
   parent: (comment, input, ctx, info) => {
     // If there isn't a parent, then return nothing!
     if (!comment.parent_id) {
diff --git a/src/core/server/graph/tenant/schema/schema.graphql b/src/core/server/graph/tenant/schema/schema.graphql
index 8a3a5e007..4b2d9ca23 100644
--- a/src/core/server/graph/tenant/schema/schema.graphql
+++ b/src/core/server/graph/tenant/schema/schema.graphql
@@ -665,6 +665,11 @@ type Comment {
   """
   parent: Comment
 
+  """
+  rootParent is the comment that is not a reply to another Comment.
+  """
+  rootParent: Comment
+
   """
   parents returns a CommentsConnection that allows accessing direct parents of
   the given Comment.