myvideogamelist.com/app/Http/Controllers/WishlistController.php

<?php

namespace App\Http\Controllers;

use App\Models\Wishlist;
use App\Models\User;
use Illuminate\Http\Request;

class WishlistController extends Controller
{
    /**
     * Display a listing of the resource.
     *
     * @return \Illuminate\Http\Response
     */
    public function index()
    {
        //
    }

    /**
     * Show the form for creating a new resource.
     *
     * @return \Illuminate\Http\Response
     */
    public function create()
    {
        //
    }

    /**
     * Store a newly created resource in storage.
     *
     * @param  \Illuminate\Http\Request  $request
     * @return \Illuminate\Http\Response
     */
    public function store(Request $request)
    {
        //
    }

    /**
     * Display the specified resource.
     *
     * @param  string  $username
     *
     * @return \Illuminate\Http\Response
     */
    public function show($username = null)
    {
        // If username is null, fetch the user_id and their wishlist items.
        if ($username === null) {
            $userId = auth()->user()->id;
            $wishlist = Wishlist::where('user_id', $userId)->whereNull('deleted_at')->get();
        } else { // Otherwise, fetch the user_id from $username and their wishlist items.
            $userId = User::whereUsername($username)->firstOrFail()->id;
            $wishlist = Wishlist::where('user_id', $userId)->get();
        }

        // Direct the user to the wishlist page.
        return view('pages.wishlist.index', compact('wishlist'));
    }

    /**
     * Show the form for editing the specified resource.
     *
     * @param  \App\Models\Wishlist  $wishlist
     * @return \Illuminate\Http\Response
     */
    public function edit(Wishlist $wishlist)
    {
        //
    }

    /**
     * Update the specified resource in storage.
     *
     * @param  \Illuminate\Http\Request  $request
     * @param  \App\Models\Wishlist  $wishlist
     * @return \Illuminate\Http\Response
     */
    public function update(Request $request, Wishlist $wishlist)
    {
        //
    }

    /**
     * Remove the specified resource from storage.
     *
     * @param  \App\Models\Wishlist  $wishlist
     * @return \Illuminate\Http\Response
     */
    public function destroy(Wishlist $wishlist)
    {
        //
    }
}