feat: add likes

+ add ability for user to like a posts
+ add ability for user ot remove a like
+ add display of reply and like count

convex/_generated/api.d.ts

@@ -15,6 +15,7 @@ import type {
   FunctionReference,
 } from "convex/server";
 import type * as http from "../http";
+import type * as likes from "../likes";
 import type * as posts from "../posts";
 import type * as users from "../users";
 
@@ -28,6 +29,7 @@ import type * as users from "../users";
  */
 declare const fullApi: ApiFromModules<{
   http: typeof http;
+  likes: typeof likes;
   posts: typeof posts;
   users: typeof users;
 }>;

convex/likes.ts

@@ -0,0 +1,99 @@
+import { v } from 'convex/values';
+import { mutation, query } from './_generated/server';
+import { userQuery } from './users';
+
+export const addLike = mutation({
+  args: { postId: v.id('posts') },
+  handler: async (ctx, args) => {
+    const clerkUser = await ctx.auth.getUserIdentity();
+
+    if (clerkUser === null) {
+      return;
+    }
+
+    const user = await userQuery(ctx, clerkUser.subject);
+
+    if (user === null) {
+      return;
+    }
+
+    const existingLike = await ctx.db
+      .query('likes')
+      .withIndex('by_user_post_id', q =>
+        q.eq('userId', user._id).eq('postId', args.postId)
+      )
+      .unique();
+
+    if (existingLike !== null) {
+      return;
+    }
+
+    await ctx.db.insert('likes', { postId: args.postId, userId: user._id });
+  },
+});
+
+export const removeLike = mutation({
+  args: { postId: v.id('posts') },
+  handler: async (ctx, args) => {
+    const clerkUser = await ctx.auth.getUserIdentity();
+
+    if (clerkUser === null) {
+      return;
+    }
+
+    const user = await userQuery(ctx, clerkUser.subject);
+
+    if (user === null) {
+      return;
+    }
+
+    const existingLike = await ctx.db
+      .query('likes')
+      .withIndex('by_user_post_id', q =>
+        q.eq('userId', user._id).eq('postId', args.postId)
+      )
+      .unique();
+
+    if (existingLike === null) {
+      return;
+    }
+
+    await ctx.db.delete(existingLike._id);
+  },
+});
+
+export const getLike = query({
+  args: { postId: v.id('posts') },
+  handler: async (ctx, args) => {
+    const clerkUser = await ctx.auth.getUserIdentity();
+
+    if (clerkUser === null) {
+      return;
+    }
+
+    const user = await userQuery(ctx, clerkUser.subject);
+
+    if (user === null) {
+      return;
+    }
+
+    return await ctx.db
+      .query('likes')
+      .withIndex('by_post_user_id', q =>
+        q.eq('postId', args.postId).eq('userId', user._id)
+      )
+      .unique();
+  },
+});
+
+export const getPostLikeCount = query({
+  args: { postId: v.id('posts') },
+  handler: async (ctx, args) => {
+    const likes = await ctx.db
+      .query('likes')
+      .withIndex('by_post_user_id', q => q.eq('postId', args.postId))
+      .collect();
+
+    return likes.length;
+  },
+});

convex/posts.ts

@@ -135,3 +135,15 @@ export const getRepliesByParentId = query({
     return { ...replies, page: repliesWithUserData };
   },
 });
+
+export const getPostReplyCount = query({
+  args: { postId: v.id('posts') },
+  handler: async (ctx, args) => {
+    const replies = await ctx.db
+      .query('posts')
+      .withIndex('by_parent_id', q => q.eq('parentPostId', args.postId))
+      .collect();
+
+    return replies.length;
+  },
+});

convex/schema.ts

@@ -42,6 +42,12 @@ export default defineSchema(
     })
       .index('by_user_id', ['userId'])
       .index('by_parent_id', ['parentPostId']),
+    likes: defineTable({
+      postId: v.id('posts'),
+      userId: v.id('users'),
+    })
+      .index('by_user_post_id', ['userId', 'postId'])
+      .index('by_post_user_id', ['postId', 'userId']),
   },
   { schemaValidation: false }
 );