feat: added language selection to courses page

package-lock.json

@@ -20,6 +20,7 @@
         "next": "^14.0.3",
         "react": "18.2.0",
         "react-dom": "18.2.0",
+        "react-hook-form": "^7.49.0",
         "server-only": "^0.0.1",
         "superjson": "^2.2.1",
         "svix": "^1.15.0",
@@ -4185,6 +4186,22 @@
         "react": "^18.2.0"
       }
     },
+    "node_modules/react-hook-form": {
+      "version": "7.49.0",
+      "resolved": "https://registry.npmjs.org/react-hook-form/-/react-hook-form-7.49.0.tgz",
+      "integrity": "sha512-gf4qyY4WiqK2hP/E45UUT6wt3Khl49pleEVcIzxhLBrD6m+GMWtLRk0vMrRv45D1ZH8PnpXFwRPv0Pewske2jw==",
+      "engines": {
+        "node": ">=18",
+        "pnpm": "8"
+      },
+      "funding": {
+        "type": "opencollective",
+        "url": "https://opencollective.com/react-hook-form"
+      },
+      "peerDependencies": {
+        "react": "^16.8.0 || ^17 || ^18"
+      }
+    },
     "node_modules/react-ssr-prepass": {
       "version": "1.5.0",
       "resolved": "https://registry.npmjs.org/react-ssr-prepass/-/react-ssr-prepass-1.5.0.tgz",

package.json

@@ -25,6 +25,7 @@
     "next": "^14.0.3",
     "react": "18.2.0",
     "react-dom": "18.2.0",
+    "react-hook-form": "^7.49.0",
     "server-only": "^0.0.1",
     "superjson": "^2.2.1",
     "svix": "^1.15.0",

src/app/courses/course-selection.tsx

@@ -1,39 +1,63 @@
 "use client";
 
-import { type FormEvent, useState } from "react";
+import { type InferSelectModel } from "drizzle-orm";
+import { redirect } from "next/navigation";
+import { useForm, type SubmitHandler } from "react-hook-form";
+import { type language } from "~/server/db/schema";
+import { api } from "~/trpc/react";
 
-export default function CourseSelection() {
-  const [selectedLanguage, setSelectedLanguage] = useState("");
+interface FormInputs {
+  languageId: bigint;
+}
 
-  const handleLanguageChange = (
-    event: React.ChangeEvent<HTMLSelectElement>,
-  ) => {
-    setSelectedLanguage(event.target.value);
-  };
+interface Props {
+  courses: InferSelectModel<typeof language>[];
+  activeLanguage?: bigint;
+}
 
-  const handleSubmit = (event: FormEvent) => {
-    event.preventDefault();
-    // Handle form submission logic here, e.g., send selectedLanguage to the server
-    console.log("Selected language:", selectedLanguage);
+export default function CourseSelection({ courses, activeLanguage }: Props) {
+  const { mutate, error } = api.language.setActiveLanguage.useMutation({
+    onSuccess: () => {
+      redirect("/home");
+    },
+  });
+
+  const {
+    register,
+    handleSubmit,
+    formState: { errors },
+    setError,
+  } = useForm<FormInputs>({ defaultValues: { languageId: activeLanguage } });
+
+  const onSubmit: SubmitHandler<FormInputs> = async (data) => {
+    if (data.languageId) {
+      mutate({ languageId: BigInt(data.languageId) });
+    } else {
+      setError("languageId", { message: "You must select a valid language." });
+    }
   };
 
   return (
-    <form className="flex flex-col gap-y-2" onSubmit={handleSubmit}>
+    <form className="flex flex-col gap-y-2" onSubmit={handleSubmit(onSubmit)}>
       <label htmlFor="course-select">Select a language:</label>
-      <select
-        id="course-select"
-        name="course"
-        value={selectedLanguage}
-        onChange={handleLanguageChange}
-        className="border"
-      >
+      <select id="course-select" className="border" {...register("languageId")}>
         <option value="">Select...</option>
-        <option value="Japanese">Japanese 🇯🇵</option>
-        <option value="French">French 🇫🇷</option>
+        {courses.map(({ name, emoji, languageId }) => (
+          <option value={languageId}>
+            {name} {emoji}
+          </option>
+        ))}
       </select>
+      {errors.languageId && (
+        <p className="text-sm text-red-500">{errors.languageId.message}</p>
+      )}
       <button type="submit" className="border">
         Submit
       </button>
+      {errors.root && (
+        <p className="text-sm text-red-500">{errors.root.message}</p>
+      )}
+      {error && <p className="text-sm text-red-500">{error.message}</p>}
     </form>
   );
 }

src/app/courses/page.tsx

@@ -1,11 +1,18 @@
 import CourseSelection from "~/app/courses/course-selection";
+import { api } from "~/trpc/server";
 
 export default async function Course() {
+  const { languages } = await api.language.getAllLanguages();
+  const activeLanguage = await api.language.getActiveLanguage();
+
   return (
-    <main className="">
+    <main className="mx-auto max-w-2xl">
       <h1 className="text-2xl font-bold">Course</h1>
       <h2 className="text-lg font-medium">Available languages</h2>
-      <CourseSelection />
+      <CourseSelection
+        courses={languages}
+        activeLanguage={activeLanguage?.activeLanguageId ?? undefined}
+      />
     </main>
   );
 }

src/app/home/page.tsx

@@ -1,7 +1,15 @@
+import { redirect } from "next/navigation";
+import { api } from "~/trpc/server";
+
 export default async function Home() {
+  const activeLanguage = await api.user.activeLanguage();
+  if (!activeLanguage.language) redirect("/courses");
+
   return (
-    <main className="">
+    <main className="mx-auto max-w-2xl">
       <h1 className="text-2xl font-bold">Home</h1>
+      <p>Active language:</p>
+      <pre>{JSON.stringify(activeLanguage, undefined, 2)}</pre>
     </main>
   );
 }

src/server/api/root.ts

@@ -1,4 +1,5 @@
-import { postRouter } from "~/server/api/routers/post";
+import { languageRouter } from "~/server/api/routers/language";
+import { userRouter } from "~/server/api/routers/user";
 import { createTRPCRouter } from "~/server/api/trpc";
 
 /**
@@ -7,7 +8,8 @@ import { createTRPCRouter } from "~/server/api/trpc";
  * All routers added in /api/routers should be manually added here.
  */
 export const appRouter = createTRPCRouter({
-  post: postRouter,
+  user: userRouter,
+  language: languageRouter,
 });
 
 // export type definition of API

src/server/api/routers/language.ts

@@ -0,0 +1,31 @@
+import { eq } from "drizzle-orm";
+import { z } from "zod";
+import {
+  createTRPCRouter,
+  protectedProcedure,
+  publicProcedure,
+} from "~/server/api/trpc";
+import { user } from "~/server/db/schema";
+
+export const languageRouter = createTRPCRouter({
+  getAllLanguages: publicProcedure.query(async ({ ctx }) => {
+    const languages = await ctx.db.query.language.findMany();
+    return { languages };
+  }),
+  getActiveLanguage: protectedProcedure.query(async ({ ctx }) => {
+    const activeLanguage = await ctx.db.query.user.findFirst({
+      columns: { activeLanguageId: true },
+      where: eq(user.userId, ctx.auth.userId),
+    });
+
+    return activeLanguage;
+  }),
+  setActiveLanguage: protectedProcedure
+    .input(z.object({ languageId: z.bigint() }))
+    .mutation(async ({ ctx, input }) => {
+      await ctx.db
+        .update(user)
+        .set({ activeLanguageId: input.languageId })
+        .where(eq(user.userId, ctx.auth.userId));
+    }),
+});

src/server/api/routers/post.ts

@@ -1,17 +0,0 @@
-import { z } from "zod";
-
-import {
-  createTRPCRouter,
-  protectedProcedure,
-  publicProcedure,
-} from "~/server/api/trpc";
-
-export const postRouter = createTRPCRouter({
-  hello: publicProcedure
-    .input(z.object({ text: z.string() }))
-    .query(({ input }) => {
-      return {
-        greeting: `Hello ${input.text}`,
-      };
-    }),
-});

src/server/api/routers/user.ts

@@ -0,0 +1,17 @@
+import { eq } from "drizzle-orm";
+import { createTRPCRouter, protectedProcedure } from "~/server/api/trpc";
+import { user } from "~/server/db/schema";
+
+export const userRouter = createTRPCRouter({
+  activeLanguage: protectedProcedure.query(async ({ ctx }) => {
+    const currentUser = await ctx.db.query.user.findFirst({
+      columns: {},
+      where: eq(user.userId, ctx.auth.userId),
+      with: { language: true },
+    });
+
+    return {
+      language: currentUser?.language,
+    };
+  }),
+});

src/server/api/trpc.ts

@@ -10,6 +10,7 @@ import { ZodError } from "zod";
 import superjson from "superjson";
 import { initTRPC, TRPCError } from "@trpc/server";
 import { type Context } from "~/server/api/context";
+import { auth } from "@clerk/nextjs/server";
 
 /**
  * 1. CONTEXT
@@ -49,12 +50,16 @@ const t = initTRPC.context<Context>().create({
 
 // check if the user is signed in, otherwise throw a UNAUTHORIZED CODE
 const enforceUserIsAuthed = t.middleware(({ next, ctx }) => {
-  if (!ctx.auth?.userId) {
+  const userAuth = auth();
+
+  if (!userAuth.userId) {
     throw new TRPCError({ code: "UNAUTHORIZED" });
   }
+
   return next({
     ctx: {
-      auth: ctx.auth,
+      ...ctx,
+      auth: userAuth,
     },
   });
 });

src/server/db/schema.ts

@@ -24,6 +24,7 @@ export const language = mysqlTable("language", {
   languageId: serial("languageId").primaryKey(),
   name: varchar("name", { length: 255 }),
   abbreviation: varchar("abbreviation", { length: 2 }),
+  emoji: varchar("emoji", { length: 2 }),
 });
 
 export const course = mysqlTable("course", {
@@ -67,9 +68,15 @@ export const courseRelations = relations(course, ({ one }) => ({
   }),
 }));
 
-export const progressRelations = relations(progress, ({ many }) => ({
-  language: many(language),
-  user: many(user),
+export const progressRelations = relations(progress, ({ one }) => ({
+  language: one(language, {
+    fields: [progress.languageId],
+    references: [language.languageId],
+  }),
+  user: one(user, {
+    fields: [progress.userId],
+    references: [user.userId],
+  }),
 }));
 
 export const contentRelations = relations(content, ({ one }) => ({