feat: all UI components, MVP implementation

src/App.tsx

@@ -1,10 +1,12 @@
 import { useState } from "react";
 import { useQuery } from "@tanstack/react-query";
 import { getPokemonByID } from "./api/pokemon";
-import { PokemonCard } from "./components/PokemonCard";
+import { PokemonCard } from "./components/PokemonCard/PokemonCard";
+import { Favorite } from "./components/Favorite/Favorite";
 
 export default function App() {
-  const [pokemonId, setPokemonId] = useState(Math.ceil(Math.random() * 493));
+  // Start at a default ID
+  const [pokemonId, setPokemonId] = useState(1);
 
   const query = useQuery({
     queryKey: ["pokemon", pokemonId],
@@ -19,6 +21,14 @@ export default function App() {
     setPokemonId((prev) => prev + 1);
   };
 
+  const handleInputChange = (e: React.ChangeEvent<HTMLInputElement>) => {
+    const value = parseInt(e.target.value, 10);
+    // Ensure the user cannot enter negative numbers or invalid text
+    if (!isNaN(value) && value > 0) {
+      setPokemonId(value);
+    }
+  };
+
   return (
     <div
       style={{
@@ -28,16 +38,27 @@ export default function App() {
         gap: "16px",
       }}
     >
-      <div style={{ display: "flex", gap: "10px" }}>
+      <div style={{ display: "flex", gap: "10px", alignItems: "center" }}>
         <button onClick={handlePrevious} disabled={pokemonId <= 1}>
           &larr; Prev
         </button>
+
+        <input
+          type="number"
+          value={pokemonId}
+          onChange={handleInputChange}
+          min="1"
+          style={{ width: "70px", textAlign: "center", padding: "4px" }}
+          aria-label="Pokemon ID"
+        />
+
         <button onClick={handleNext}>Next &rarr;</button>
       </div>
 
       {query.isPending && <h1>Loading...</h1>}
       {query.isError && <h1>Failed to load Pokemon</h1>}
       {query.data && <PokemonCard pokemon={query.data} />}
+      <Favorite pokemonId={pokemonId} />
     </div>
   );
 }

src/components/Favorite/Favorite.css

@@ -0,0 +1,25 @@
+.favorite-button {
+  background: transparent;
+  border: none;
+  font-size: 1.5rem;
+  cursor: pointer;
+  padding: 0.5rem;
+  border-radius: 50%;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  transition: transform 0.2s ease-in-out;
+}
+
+.favorite-button:hover {
+  transform: scale(1.2);
+}
+
+.favorite-button:focus-visible {
+  outline: 2px solid #0056b3;
+  outline-offset: 2px;
+}
+
+.favorite-button:active {
+  transform: scale(0.9);
+}

src/components/Favorite/Favorite.tsx

@@ -0,0 +1,46 @@
+import { useState } from "react";
+import "./Favorite.css";
+
+type FavoriteProps = {
+  pokemonId: number;
+};
+
+export function Favorite({ pokemonId }: FavoriteProps) {
+  // 1. Lazy initialization from localStorage
+  const [favorites, setFavorites] = useState<number[]>(() => {
+    try {
+      const storedFavorites = window.localStorage.getItem("favorites");
+      return storedFavorites ? JSON.parse(storedFavorites) : [];
+    } catch (error) {
+      console.error("Error reading localStorage", error);
+      return [];
+    }
+  });
+
+  const isFavorite = favorites.includes(pokemonId);
+
+  // 2. The click handler syncing State and Storage
+  const toggleFavorite = () => {
+    let updatedFavorites: number[];
+
+    if (isFavorite) {
+      updatedFavorites = favorites.filter((id) => id !== pokemonId);
+    } else {
+      updatedFavorites = [...favorites, pokemonId];
+    }
+
+    setFavorites(updatedFavorites);
+    window.localStorage.setItem("favorites", JSON.stringify(updatedFavorites));
+  };
+
+  // 3. Accessible UI rendering
+  return (
+    <button
+      onClick={toggleFavorite}
+      aria-label={isFavorite ? "Remove from favorites" : "Add to favorites"}
+      className="favorite-button"
+    >
+      {isFavorite ? "❤️" : "🤍"}
+    </button>
+  );
+}