task solution was added

src/App.tsx

@@ -1,61 +1,86 @@
-import React from 'react';
+import React, { useState, useContext } from 'react';
 import 'bulma/bulma.sass';
 import '@fortawesome/fontawesome-free/css/all.css';
 import './App.scss';
 
-import classNames from 'classnames';
+import cn from 'classnames';
 import { PostsList } from './components/PostsList';
 import { PostDetails } from './components/PostDetails';
 import { UserSelector } from './components/UserSelector';
 import { Loader } from './components/Loader';
+import { User } from './types/User';
+import { PostContext } from './PostContext';
 
 export const App: React.FC = () => {
+  const [selectedUser, setSelectedUser] = useState<User | null>(null);
+
+  const {
+    posts,
+    isPostLoading,
+    isPostLoadError,
+    selectedPost,
+  } = useContext(PostContext);
+
   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 />
+                <UserSelector
+                  selectedUser={selectedUser}
+                  setSelectedUser={setSelectedUser}
+                />
               </div>
 
               <div className="block" data-cy="MainContent">
-                <p data-cy="NoSelectedUser">
-                  No user selected
-                </p>
+                {!selectedUser && (
+                  <p data-cy="NoSelectedUser">
+                    No user selected
+                  </p>
+                )}
 
-                <Loader />
+                {isPostLoading && <Loader />}
 
-                <div
-                  className="notification is-danger"
-                  data-cy="PostsLoadingError"
-                >
-                  Something went wrong!
-                </div>
+                {isPostLoadError && (
+                  <div
+                    className="notification is-danger"
+                    data-cy="PostsLoadingError"
+                  >
+                    Something went wrong!
+                  </div>
+                )}
 
-                <div className="notification is-warning" data-cy="NoPostsYet">
-                  No posts yet
-                </div>
+                {!isPostLoading
+                  && !isPostLoadError
+                  && posts.length === 0
+                  && selectedUser && (
+                  <div className="notification is-warning" data-cy="NoPostsYet">
+                    No posts yet
+                  </div>
+                )}
 
-                <PostsList />
+                {selectedUser && !!posts.length && <PostsList />}
               </div>
             </div>
           </div>
 
           <div
             data-cy="Sidebar"
-            className={classNames(
+            className={cn(
               'tile',
               'is-parent',
               'is-8-desktop',
               'Sidebar',
-              'Sidebar--open',
+              { 'Sidebar--open': selectedPost },
             )}
           >
-            <div className="tile is-child box is-success ">
-              <PostDetails />
-            </div>
+            {!isPostLoadError && (
+              <div className="tile is-child box is-success">
+                <PostDetails />
+              </div>
+            )}
           </div>
         </div>
       </div>

src/CommentsContext.tsx

@@ -0,0 +1,89 @@
+import React, { useMemo, useState } from 'react';
+import { Comment } from './types/Comment';
+import { deleteComment } from './api/Comments';
+
+type CommentsState = {
+  comments: Comment[],
+  setComments: (comments: Comment[]) => void,
+  isCommentLoading: boolean,
+  setIsCommentLoading: (value: boolean) => void,
+  isCommentLoadError: boolean,
+  setIsCommentLoadError: (value: boolean) => void,
+  isCommentDeleteError: boolean,
+  setIsCommentDeleteError: (value: boolean) => void,
+  isCommentUpdateError: boolean,
+  setIsCommentUpdateError: (value: boolean) => void,
+  isFormShown: boolean,
+  setIsFormShown: (value: boolean) => void,
+  hadnleCommentDelete: (id: number) => void;
+};
+
+export const CommentsContext = React.createContext<CommentsState>({
+  comments: [],
+  setComments: () => {},
+  isCommentLoading: false,
+  setIsCommentLoading: () => {},
+  isCommentLoadError: false,
+  setIsCommentLoadError: () => {},
+  isCommentDeleteError: false,
+  setIsCommentDeleteError: () => {},
+  isCommentUpdateError: false,
+  setIsCommentUpdateError: () => {},
+  isFormShown: false,
+  setIsFormShown: () => {},
+  hadnleCommentDelete: () => {},
+});
+
+interface Props {
+  children: React.ReactNode,
+}
+
+export const CommentsProvider: React.FC<Props> = ({ children }) => {
+  const [comments, setComments] = useState<Comment[]>([]);
+  const [isCommentLoading, setIsCommentLoading] = useState(false);
+  const [isCommentLoadError, setIsCommentLoadError] = useState(false);
+  const [isCommentDeleteError, setIsCommentDeleteError] = useState(false);
+  const [isCommentUpdateError, setIsCommentUpdateError] = useState(false);
+
+  const [isFormShown, setIsFormShown] = useState(false);
+
+  const hadnleCommentDelete = (id: number) => {
+    setIsCommentDeleteError(false);
+    deleteComment(id)
+      .then(() => setComments(
+        currentComments => currentComments.filter(comment => comment.id !== id),
+      ))
+      .catch(() => {
+        setIsCommentDeleteError(true);
+      });
+  };
+
+  const value = useMemo(() => ({
+    comments,
+    setComments,
+    isCommentLoading,
+    setIsCommentLoading,
+    isCommentLoadError,
+    setIsCommentLoadError,
+    isCommentDeleteError,
+    setIsCommentDeleteError,
+    isCommentUpdateError,
+    setIsCommentUpdateError,
+    isFormShown,
+    setIsFormShown,
+    hadnleCommentDelete,
+  }), [
+    comments,
+    isCommentLoading,
+    isCommentLoadError,
+    isCommentDeleteError,
+    isCommentUpdateError,
+    isFormShown,
+  ]);
+
+  return (
+    <CommentsContext.Provider value={value}>
+      {children}
+    </CommentsContext.Provider>
+  );
+};

src/PostContext.tsx

@@ -0,0 +1,52 @@
+import React, { useMemo, useState } from 'react';
+import { Post } from './types/Post';
+
+type PostState = {
+  posts: Post[],
+  setPosts: (comments: Post[]) => void,
+  selectedPost: Post | null,
+  setSelectedPost: (post: Post | null) => void,
+  isPostLoading: boolean,
+  setIsPostLoading: (value: boolean) => void,
+  isPostLoadError: boolean,
+  setIsPostLoadError: (value: boolean) => void,
+};
+
+export const PostContext = React.createContext<PostState>({
+  posts: [],
+  setPosts: () => {},
+  selectedPost: null,
+  setSelectedPost: () => {},
+  isPostLoading: false,
+  setIsPostLoading: () => {},
+  isPostLoadError: false,
+  setIsPostLoadError: () => {},
+});
+
+interface Props {
+  children: React.ReactNode,
+}
+
+export const PostProvider: React.FC<Props> = ({ children }) => {
+  const [posts, setPosts] = useState<Post[]>([]);
+  const [selectedPost, setSelectedPost] = useState<Post | null>(null);
+  const [isPostLoading, setIsPostLoading] = useState(false);
+  const [isPostLoadError, setIsPostLoadError] = useState(false);
+
+  const value = useMemo(() => ({
+    posts,
+    setPosts,
+    selectedPost,
+    setSelectedPost,
+    isPostLoading,
+    setIsPostLoading,
+    isPostLoadError,
+    setIsPostLoadError,
+  }), [posts, isPostLoading, isPostLoadError, selectedPost]);
+
+  return (
+    <PostContext.Provider value={value}>
+      {children}
+    </PostContext.Provider>
+  );
+};

src/api/Comments.tsx

@@ -0,0 +1,22 @@
+import { Comment, CommentData } from '../types/Comment';
+import { client } from '../utils/fetchClient';
+
+export const getComments = (postId: number) => {
+  return client.get<Comment[]>(`/comments?postId=${postId}`);
+};
+
+export const addComment = (
+  postId: number,
+  { name, email, body }: CommentData,
+) => {
+  return client.post<Comment>('/comments', {
+    postId,
+    name,
+    email,
+    body,
+  });
+};
+
+export const deleteComment = (commentId: number) => {
+  return client.delete(`/comments/${commentId}`);
+};

src/api/Posts.tsx

@@ -0,0 +1,6 @@
+import { Post } from '../types/Post';
+import { client } from '../utils/fetchClient';
+
+export const getPosts = (userId: number) => {
+  return client.get<Post[]>(`/posts?userId=${userId}`);
+};

src/api/Users.tsx

@@ -0,0 +1,6 @@
+import { User } from '../types/User';
+import { client } from '../utils/fetchClient';
+
+export const getUsers = () => {
+  return client.get<User[]>('/users');
+};

src/components/Loader/Loader.tsx

@@ -1,6 +1,7 @@
+import React from 'react';
 import './Loader.scss';
 
-export const Loader = () => (
+export const Loader: React.FC = () => (
   <div className="Loader" data-cy="Loader">
     <div className="Loader__content" />
   </div>