Added shelf template shared between shelf and post page.

src/posts.js

@@ -6,6 +6,13 @@ import { HttpError } from './errors';
 import { fetchShelf } from './shelves';
 import { fetchUsers } from './users';
 
+const emptyVote = {
+	tally: 0,
+	total: 0,
+	bump: false,
+	sink: false,
+};
+
 function curateDatabasePost(post, {
 	shelf, users, votes,
 }) {
@@ -18,7 +25,7 @@ function curateDatabasePost(post, {
 		createdAt: post.created_at,
 		shelf,
 		user: users.find((user) => user.id === post.user_id),
-		votes: votes[post.id],
+		vote: votes[post.id] || emptyVote,
 		commentCount: Number(post.comment_count),
 	};
 
@@ -123,19 +130,27 @@ async function createPost(post, shelfId, user) {
 }
 
 async function votePost(postId, value, user) {
-	await knex('posts_votes')
-		.insert({
-			value,
-			post_id: postId,
-			user_id: user.id,
-		})
-		.onConflict(['post_id', 'user_id'])
-		.merge()
-		.returning('value');
+	if (value === 0) {
+		await knex('posts_votes')
+			.where({
+				post_id: postId,
+				user_id: user.id,
+			})
+			.delete();
+	} else {
+		await knex('posts_votes')
+			.insert({
+				value,
+				post_id: postId,
+				user_id: user.id,
+			})
+			.onConflict(['post_id', 'user_id'])
+			.merge();
+	}
 
 	const votes = await fetchPostVotes([postId], user);
 
-	return votes[postId];
+	return votes[postId] || emptyVote;
 }
 
 export {