solution

src/App.tsx

@@ -8,53 +8,116 @@ import { PostsList } from './components/PostsList';
 import { PostDetails } from './components/PostDetails';
 import { UserSelector } from './components/UserSelector';
 import { Loader } from './components/Loader';
+import { useEffect, useState } from 'react';
+import { User } from './types/User';
+import { userClient } from './utils/userClient';
+import { postClient } from './utils/postClient';
+import { Post } from './types/Post';
 
-export const App = () => (
-  <main className="section">
-    <div className="container">
-      <div className="tile is-ancestor">
-        <div className="tile is-parent">
-          <div className="tile is-child box is-success">
-            <div className="block">
-              <UserSelector />
-            </div>
+export const App = () => {
+  //region States
+  const [users, setUsers] = useState<User[]>([]);
+  const [userSelected, setUserSelected] = useState<User | null>(null);
+  const [userSelPosts, setUserSelPosts] = useState<Post[]>([]);
+  const [openedPost, setOpendPost] = useState<Post | null>(null);
+  const [error, setError] = useState(false);
+  const [loading, setLoading] = useState(false);
+  //endregion
 
-            <div className="block" data-cy="MainContent">
-              <p data-cy="NoSelectedUser">No user selected</p>
+  //Init users
+  useEffect(() => {
+    setLoading(true);
+    userClient
+      .getAll()
+      .then(res => {
+        setUsers(res);
+        setError(false);
+      })
+      .catch(() => setError(true))
+      .finally(() => setLoading(false));
+  }, []);
 
-              <Loader />
+  // Update User Posts
+  useEffect(() => {
+    setOpendPost(null);
 
-              <div
-                className="notification is-danger"
-                data-cy="PostsLoadingError"
-              >
-                Something went wrong!
-              </div>
+    if (userSelected) {
+      setLoading(true);
+      postClient
+        .get(userSelected.id)
+        .then(res => {
+          setUserSelPosts(() => res);
+          setError(false);
+        })
+        .catch(() => setError(true))
+        .finally(() => {
+          setLoading(false);
+        });
+    }
+  }, [userSelected]);
+
+  const handleUserSelect = (user: User) => {
+    setUserSelected(user);
+  };
 
-              <div className="notification is-warning" data-cy="NoPostsYet">
-                No posts yet
+  return (
+    <main className="section">
+      <div className="container">
+        <div className="tile is-ancestor">
+          <div className="tile is-parent">
+            <div className="tile is-child box is-success">
+              <div className="block">
+                <UserSelector users={users} onSelect={handleUserSelect} />
               </div>
 
-              <PostsList />
+              <div className="block" data-cy="MainContent">
+                {!userSelected && (
+                  <p data-cy="NoSelectedUser">No user selected</p>
+                )}
+
+                {loading && <Loader />}
+
+                {error && (
+                  <div
+                    className="notification is-danger"
+                    data-cy="PostsLoadingError"
+                  >
+                    Something went wrong!
+                  </div>
+                )}
+
+                {userSelected && !loading ? (
+                  userSelPosts.length > 0 ? (
+                    <PostsList posts={userSelPosts} onOpen={setOpendPost} />
+                  ) : (
+                    <div
+                      className="notification is-warning"
+                      data-cy="NoPostsYet"
+                    >
+                      No posts yet
+                    </div>
+                  )
+                ) : undefined}
+              </div>
             </div>
           </div>
-        </div>
 
-        <div
-          data-cy="Sidebar"
-          className={classNames(
-            'tile',
-            'is-parent',
-            'is-8-desktop',
-            'Sidebar',
-            'Sidebar--open',
-          )}
-        >
-          <div className="tile is-child box is-success ">
-            <PostDetails />
+          <div
+            data-cy="Sidebar"
+            className={classNames(
+              'tile',
+              'is-parent',
+              'is-8-desktop',
+              'Sidebar',
+              { 'Sidebar--close': !openedPost, 'Sidebar--open': openedPost },
+            )}
+          >
+            <div className="tile is-child box is-success ">
+              <PostDetails post={openedPost} />
+            </div>
           </div>
         </div>
       </div>
-    </div>
-  </main>
-);
+    </main>
+  );
+};

src/components/Comment.tsx

@@ -0,0 +1,31 @@
+import { Comment } from '../types/Comment';
+
+type Props = {
+  comment: Comment;
+  onDelete: (id: number) => void;
+};
+
+export const CommentObj: React.FC<Props> = ({ comment, onDelete }) => {
+  return (
+    <article key={comment.id} className="message is-small" data-cy="Comment">
+      <div className="message-header">
+        <a href={`mailto:${comment.email}`} data-cy="CommentAuthor">
+          {comment.name}
+        </a>
+        <button
+          data-cy="CommentDelete"
+          type="button"
+          className="delete is-small"
+          aria-label="delete"
+          onClick={() => onDelete(comment.id)}
+        >
+          delete button
+        </button>
+      </div>
+
+      <div className="message-body" data-cy="CommentBody">
+        {comment.body}
+      </div>
+    </article>
+  );
+};

src/components/CommentList.tsx

@@ -0,0 +1,29 @@
+import { Comment } from '../types/Comment';
+import { CommentObj } from './Comment';
+
+type Props = {
+  comments: Comment[];
+  onDelete: (id: number) => void;
+};
+
+export const CommentList: React.FC<Props> = ({ comments, onDelete }) => {
+  return (
+    <>
+      {comments.length > 0 ? (
+        comments.map(comment => {
+          return (
+            <CommentObj
+              key={comment.id}
+              comment={comment}
+              onDelete={onDelete}
+            />
+          );
+        })
+      ) : (
+        <p className="title is-4" data-cy="NoCommentsMessage">
+          No comments yet
+        </p>
+      )}
+    </>
+  );
+};