diff --git a/src/App.tsx b/src/App.tsx
index 81e011f432..1b1d222259 100644
--- a/src/App.tsx
+++ b/src/App.tsx
@@ -1,26 +1,311 @@
-/* eslint-disable max-len */
+/* eslint-disable jsx-a11y/label-has-associated-control */
 /* eslint-disable jsx-a11y/control-has-associated-label */
-import React from 'react';
-import { UserWarning } from './UserWarning';
-
-const USER_ID = 0;
+import React, { FormEvent, useEffect, useRef, useState } from 'react';
+// import { UserWarning } from './UserWarning';
+import {
+  deleteTodos,
+  editTodos,
+  getTodos,
+  postTodos,
+  USER_ID,
+} from './api/todos';
+import { Todo } from './types/Todo';
+import { Footer } from './Footer';
+import { TodoList } from './TodoList';
+import classNames from 'classnames';
+import { Filters } from './types/Filters';
+import { TodoItem } from './TodoItem';
 
 export const App: React.FC = () => {
-  if (!USER_ID) {
-    return <UserWarning />;
-  }
+  const [todos, setTodos] = useState<Todo[]>([]);
+  const [deletingTodoId, setDeletingTodoId] = useState<number | null>(null);
+  const [error, setError] = useState<string | null>(null);
+  const [addTodoTitle, setAddTodoTitle] = useState('');
+  const [isSubmitting, setIsSubmitting] = useState(false);
+  const [filterSelected, setFilterSelected] = useState<Filters>(Filters.All);
+  const [tempTodo, setTempTodo] = useState<Todo | null>(null);
+  const [updatingStatusIds, setUpdatingStatusIds] = useState<Set<number>>(
+    new Set(),
+  );
+  const [clearingCompletedIds, setClearingCompletedIds] = useState<Set<number>>(
+    new Set(),
+  );
+
+  const [allCompleted, setAllCompleted] = useState(false);
+
+  const ref = useRef<HTMLInputElement | null>(null);
+
+  const updateTodos = (todoId, title) => {
+    // prettier-ignore
+    setTodos(prevState =>
+      title === null
+        ? prevState.filter(todo => todo.id !== todoId)
+        : prevState.map(todo => todoId === todo.id
+          ? { ...todo, title: title } : todo,),
+    );
+  };
+
+  const handleDelete = async (todoId: number) => {
+    setDeletingTodoId(todoId);
+    try {
+      await deleteTodos(todoId);
+      updateTodos(todoId, null);
+      ref.current.focus();
+    } catch (Error) {
+      setError('Unable to delete a todo');
+    }
+  };
+
+  const updateStatus = (todoId, completed) => {
+    // prettier-ignore
+    setTodos(prevState =>
+      prevState.map(todo => todoId === todo.id
+        ? { ...todo, completed: completed } : todo,),
+    );
+  };
+
+  const handleSubmit = async (event: FormEvent<HTMLFormElement>) => {
+    event.preventDefault();
+    const trimmedTitle = addTodoTitle.trim();
+
+    if (!trimmedTitle) {
+      setError('Title should not be empty');
+
+      return;
+    }
+
+    setTempTodo({
+      id: 0,
+      title: trimmedTitle,
+      completed: false,
+      userId: USER_ID,
+    });
+
+    setIsSubmitting(true);
+    try {
+      const newTodo = {
+        title: trimmedTitle,
+        completed: false,
+        userId: USER_ID,
+      };
+      const createdTodo = await postTodos(newTodo);
+
+      setTodos(prevState => [...prevState, createdTodo]);
+      setTempTodo(null);
+      setAddTodoTitle('');
+    } catch {
+      setError('Unable to add a todo');
+
+      setTempTodo(null);
+    } finally {
+      setIsSubmitting(false);
+    }
+  };
+
+  const handleStatus = async (todoId, completed) => {
+    setUpdatingStatusIds(prev => new Set(prev.add(todoId)));
+    const todoToUpdate = todos.find(todo => todo.id === todoId);
+
+    const updatedTodo = {
+      title: todoToUpdate.title,
+      completed: !completed,
+      todoId,
+    };
+
+    try {
+      await editTodos(updatedTodo);
+      updateStatus(todoId, !completed);
+    } catch (Error) {
+      setError('Unable to update a todo');
+    } finally {
+      setUpdatingStatusIds(prev => {
+        const updated = new Set(prev);
+
+        updated.delete(todoId);
+
+        return updated;
+      });
+    }
+  };
+
+  const handleToggleAll = async () => {
+    const IsAllCompleted = todos.every(todo => todo.completed);
+    const todosToUpdate = todos.filter(
+      todo => todo.completed !== !allCompleted,
+    );
+
+    setIsSubmitting(true);
+
+    try {
+      const updatePromises = todosToUpdate.map(async todo => {
+        setUpdatingStatusIds(prev => new Set(prev.add(todo.id)));
+        await editTodos({
+          title: todo.title,
+          completed: !IsAllCompleted,
+          todoId: todo.id,
+        });
+        updateStatus(todo.id, !IsAllCompleted);
+        setUpdatingStatusIds(prev => {
+          const updated = new Set(prev);
+
+          updated.delete(todo.id);
+
+          return updated;
+        });
+      });
+
+      await Promise.all(updatePromises);
+    } catch (Error) {
+      setError('Unable to update a todo');
+    } finally {
+      setIsSubmitting(false);
+    }
+  };
+
+  const handleClearCompleted = async () => {
+    const completedTodos = todos.filter(todo => todo.completed);
+
+    setClearingCompletedIds(new Set(completedTodos.map(todo => todo.id)));
+    try {
+      await Promise.all(
+        completedTodos.map(async todo => {
+          await handleDelete(todo.id);
+        }),
+      );
+    } catch {
+      setError('Unable to delete a todo');
+    } finally {
+      setClearingCompletedIds(new Set());
+    }
+  };
+
+  const filteredTodos = () => {
+    if (filterSelected === Filters.Active) {
+      return todos.filter(todo => !todo.completed);
+    }
+
+    if (filterSelected === Filters.Completed) {
+      return todos.filter(todo => todo.completed);
+    }
+
+    return todos;
+  };
+
+  useEffect(() => {
+    getTodos()
+      .then(setTodos)
+      .catch(() => {
+        setError('Unable to load todos');
+      });
+  }, []);
+
+  useEffect(() => {
+    const IsAllCompleted = todos.every(todo => todo.completed);
+
+    setAllCompleted(IsAllCompleted);
+  }, [todos]);
+
+  useEffect(() => {
+    if (error) {
+      const timer = setTimeout(() => {
+        setError(null);
+      }, 3000);
+
+      return () => clearTimeout(timer);
+    }
+  }, [error]);
+
+  useEffect(() => {
+    if (!isSubmitting && ref.current) {
+      ref.current.focus();
+    }
+  }, [isSubmitting]);
 
   return (
-    <section className="section container">
-      <p className="title is-4">
-        Copy all you need from the prev task:
-        <br />
-        <a href="https://github.com/mate-academy/react_todo-app-add-and-delete#react-todo-app-add-and-delete">
-          React Todo App - Add and Delete
-        </a>
-      </p>
-
-      <p className="subtitle">Styles are already copied</p>
-    </section>
+    <div className="todoapp">
+      <h1 className="todoapp__title">todos</h1>
+
+      <div className="todoapp__content">
+        <header className="todoapp__header">
+          {todos.length !== 0 && (
+            <button
+              disabled={isSubmitting}
+              type="button"
+              className={classNames('todoapp__toggle-all', {
+                active: allCompleted,
+              })}
+              data-cy="ToggleAllButton"
+              onClick={() => handleToggleAll()}
+            />
+          )}
+          <form
+            onSubmit={event => {
+              handleSubmit(event);
+            }}
+          >
+            <input
+              ref={ref}
+              disabled={isSubmitting}
+              data-cy="NewTodoField"
+              type="text"
+              className="todoapp__new-todo"
+              placeholder="What needs to be done?"
+              value={addTodoTitle}
+              onChange={event => {
+                setAddTodoTitle(event.target.value);
+              }}
+            />
+          </form>
+        </header>
+
+        <TodoList
+          todos={filteredTodos()}
+          deletingTodoId={deletingTodoId}
+          updateTodos={updateTodos}
+          updateStatus={updateStatus}
+          setTodos={setTodos}
+          setError={setError}
+          handleDelete={handleDelete}
+          handleStatus={handleStatus}
+          updatingStatusIds={updatingStatusIds}
+          clearingCompletedIds={clearingCompletedIds}
+        />
+
+        {tempTodo && (
+          <TodoItem
+            todo={tempTodo}
+            todos={[]}
+            updateTodos={() => {}}
+            setTodos={() => {}}
+            setError={setError}
+            handleDelete={() => {}}
+            tempTodo={tempTodo}
+          />
+        )}
+        {!!todos.length && (
+          <Footer
+            todos={todos}
+            filterSelected={filterSelected}
+            setFilterSelected={setFilterSelected}
+            handleDelete={handleDelete}
+            clearingCompletedIds={clearingCompletedIds}
+            handleClearCompleted={handleClearCompleted}
+          />
+        )}
+      </div>
+
+      <div
+        data-cy="ErrorNotification"
+        className={`notification is-danger is-light has-text-weight-normal ${error ? '' : 'hidden'}`}
+      >
+        <button
+          data-cy="HideErrorButton"
+          type="button"
+          className="delete"
+          onClick={() => setError(null)}
+        />
+        {error}
+      </div>
+    </div>
   );
 };
diff --git a/src/Footer.tsx b/src/Footer.tsx
new file mode 100644
index 0000000000..47231ec99c
--- /dev/null
+++ b/src/Footer.tsx
@@ -0,0 +1,52 @@
+import { Todo } from './types/Todo';
+import classNames from 'classnames';
+import { Filters } from './types/Filters';
+
+type Props = {
+  todos: Todo[];
+};
+
+export const Footer: React.FC<Props> = ({
+  todos,
+  filterSelected,
+  setFilterSelected,
+  handleClearCompleted,
+}) => {
+  const remainingTodosCount = todos.filter(todo => !todo.completed).length;
+
+  const filterOptions: Filters[] = Object.values(Filters) as Filters[];
+
+  return (
+    <footer className="todoapp__footer" data-cy="Footer">
+      <span className="todo-count" data-cy="TodosCounter">
+        {remainingTodosCount} items left
+      </span>
+
+      <nav className="filter" data-cy="Filter">
+        {filterOptions.map((filter: Filters) => (
+          <a
+            key={filter}
+            href={`#/${filter.toLowerCase()}`}
+            className={classNames('filter__link', {
+              selected: filterSelected === filter,
+            })}
+            data-cy={`FilterLink${filter}`}
+            onClick={() => setFilterSelected(filter)}
+          >
+            {filter}
+          </a>
+        ))}
+      </nav>
+
+      <button
+        type="button"
+        className="todoapp__clear-completed"
+        data-cy="ClearCompletedButton"
+        onClick={handleClearCompleted}
+        disabled={todos.every(todo => !todo.completed)}
+      >
+        Clear completed
+      </button>
+    </footer>
+  );
+};
diff --git a/src/TodoItem.tsx b/src/TodoItem.tsx
new file mode 100644
index 0000000000..beeac32ec6
--- /dev/null
+++ b/src/TodoItem.tsx
@@ -0,0 +1,208 @@
+import React, { useEffect, useRef, useState } from 'react';
+import classNames from 'classnames';
+import { editTodos } from './api/todos';
+import { Todo } from './types/Todo';
+
+type Props = {
+  todo: Todo;
+  todos: Todo[];
+};
+
+export const TodoItem: React.FC<Props> = ({
+  todo: { id, title, completed },
+  todos,
+  updateTodos,
+  setError,
+  handleDelete,
+  tempTodo,
+  isDeleting,
+  handleStatus,
+  updatingStatusIds,
+  clearingCompletedIds,
+}) => {
+  const [editingId, setEditingId] = useState<null | number>(null);
+  const [editingVal, setEditingVal] = useState('');
+  const [isUpdatingTitle, setIsUpdatingTitle] = useState(false);
+
+  const ref = useRef<HTMLInputElement | null>(null);
+
+  const handleDouble = (todoId: number, todoTitle: string) => {
+    setEditingId(todoId);
+    setEditingVal(todoTitle);
+  };
+
+  const handleSubmit = async (todoId: number) => {
+    if (isUpdatingTitle) {
+      return;
+    }
+
+    if (editingVal.trim() === '') {
+      handleDelete(todoId);
+
+      return;
+    }
+
+    if (editingVal.trim() === title) {
+      setEditingId(null);
+
+      return;
+    }
+
+    const todoToUpdate = todos.find(todo => todo.id === todoId);
+    const updatedTodo = {
+      title: editingVal,
+      todoId: todoToUpdate.id,
+      completed: completed,
+    };
+
+    setIsUpdatingTitle(true);
+
+    try {
+      await editTodos(updatedTodo);
+      updateTodos(todoId, editingVal.trim());
+      setEditingId(null);
+      setIsUpdatingTitle(true);
+    } catch (error) {
+      setError('Unable to update a todo');
+    } finally {
+      setIsUpdatingTitle(false);
+    }
+  };
+
+  const handleBlur = (todoId: number) => {
+    if (!isUpdatingTitle) {
+      handleSubmit(todoId);
+    }
+  };
+
+  const handleKeyDown = (
+    event: React.KeyboardEvent<HTMLInputElement>,
+    todoId: number,
+  ) => {
+    if (event.key === 'Enter') {
+      event.preventDefault();
+      handleSubmit(todoId);
+    } else if (event.key === 'Escape') {
+      setEditingId(null);
+      setEditingVal(title);
+    }
+  };
+
+  useEffect(() => {
+    if (editingId !== null && ref.current) {
+      (ref.current as HTMLInputElement).focus();
+    }
+  }, [editingId]);
+
+  if (tempTodo && tempTodo.id === id) {
+    return (
+      <div data-cy="Todo" className="todo">
+        <label htmlFor={`todo-0`} className="todo__status-label">
+          {}
+          <input
+            checked={tempTodo.completed}
+            data-cy="TodoStatus"
+            type="checkbox"
+            className="todo__status"
+            id={`todo-0`}
+            disabled
+          />
+        </label>
+        <span data-cy="TodoTitle" className="todo__title">
+          {tempTodo.title}
+        </span>
+        <button
+          type="button"
+          className="todo__remove"
+          data-cy="TodoDelete"
+          disabled
+        >
+          ×
+        </button>
+        <div data-cy="TodoLoader" className="modal overlay is-active">
+          <div className="modal-background has-background-white-ter" />
+          <div className="loader" />
+        </div>
+      </div>
+    );
+  }
+
+  return (
+    <div
+      key={id}
+      data-cy="Todo"
+      className={classNames('todo', { completed: completed })}
+    >
+      <label htmlFor={`todo-${id}`} className="todo__status-label">
+        {}
+        <input
+          id={`todo-${id}`}
+          checked={completed}
+          data-cy="TodoStatus"
+          type="checkbox"
+          className="todo__status"
+          onChange={() => {
+            handleStatus(id, completed);
+          }}
+        />
+      </label>
+
+      {editingId === id ? (
+        <form
+          onSubmit={e => {
+            e.preventDefault();
+            handleSubmit(id);
+          }}
+        >
+          <input
+            ref={ref}
+            data-cy="TodoTitleField"
+            type="text"
+            className="todo__title-field"
+            value={editingVal}
+            onChange={event => {
+              setEditingVal(event.target.value);
+            }}
+            onBlur={() => {
+              handleBlur(id);
+            }}
+            onKeyDown={event => handleKeyDown(event, id)}
+          />
+        </form>
+      ) : (
+        <span
+          data-cy="TodoTitle"
+          className="todo__title"
+          onDoubleClick={() => handleDouble(id, title)}
+        >
+          {title}
+        </span>
+      )}
+      {editingId !== id && (
+        <button
+          type="button"
+          className="todo__remove"
+          data-cy="TodoDelete"
+          onClick={() => handleDelete(id)}
+          disabled={isDeleting}
+        >
+          ×
+        </button>
+      )}
+
+      <div
+        data-cy="TodoLoader"
+        className={classNames('modal overlay', {
+          'is-active':
+            clearingCompletedIds.has(id) ||
+            isDeleting ||
+            isUpdatingTitle ||
+            updatingStatusIds.has(id),
+        })}
+      >
+        <div className="modal-background has-background-white-ter" />
+        <div className="loader" />
+      </div>
+    </div>
+  );
+};
diff --git a/src/TodoList.tsx b/src/TodoList.tsx
new file mode 100644
index 0000000000..73b563e573
--- /dev/null
+++ b/src/TodoList.tsx
@@ -0,0 +1,40 @@
+import { Todo } from './types/Todo';
+import { TodoItem } from './TodoItem';
+
+type Props = {
+  todos: Todo[];
+};
+
+export const TodoList: React.FC<Props> = ({
+  deletingTodoId,
+  todos,
+  updateTodos,
+  setTodos,
+  setError,
+  updateStatus,
+  handleDelete,
+  handleStatus,
+  updatingStatusIds,
+  clearingCompletedIds,
+}) => {
+  return (
+    <section className="todoapp__main" data-cy="TodoList">
+      {todos.map(todo => (
+        <TodoItem
+          isDeleting={deletingTodoId === todo.id}
+          todo={todo}
+          todos={todos}
+          updateTodos={updateTodos}
+          setTodos={setTodos}
+          setError={setError}
+          key={todo.id}
+          updateStatus={updateStatus}
+          handleDelete={handleDelete}
+          handleStatus={handleStatus}
+          updatingStatusIds={updatingStatusIds}
+          clearingCompletedIds={clearingCompletedIds}
+        />
+      ))}
+    </section>
+  );
+};
diff --git a/src/api/todos.ts b/src/api/todos.ts
new file mode 100644
index 0000000000..d42336d97e
--- /dev/null
+++ b/src/api/todos.ts
@@ -0,0 +1,24 @@
+import { Todo } from '../types/Todo';
+import { client } from '../utils/fetchClient';
+
+export const USER_ID = 1879;
+
+export const getTodos = () => {
+  return client.get<Todo[]>(`/todos?userId=${USER_ID}`);
+};
+
+export const postTodos = (data: Omit<Todo, 'id'>) => {
+  return client.post<Todo>(`/todos`, data);
+};
+
+export const editTodos = (data: {
+  title: string;
+  completed: boolean;
+  todoId: number;
+}) => {
+  return client.patch<Todo>(`/todos/${data.todoId}`, data);
+};
+
+export const deleteTodos = (id: number) => {
+  return client.delete<Todo>(`/todos/${id}`);
+};
diff --git a/src/types/Filters.ts b/src/types/Filters.ts
new file mode 100644
index 0000000000..6c26945612
--- /dev/null
+++ b/src/types/Filters.ts
@@ -0,0 +1,5 @@
+export enum Filters {
+  All = 'All',
+  Active = 'Active',
+  Completed = 'Completed',
+}
diff --git a/src/types/Todo.ts b/src/types/Todo.ts
new file mode 100644
index 0000000000..3f52a5fdde
--- /dev/null
+++ b/src/types/Todo.ts
@@ -0,0 +1,6 @@
+export interface Todo {
+  id: number;
+  userId: number;
+  title: string;
+  completed: boolean;
+}
diff --git a/src/utils/fetchClient.ts b/src/utils/fetchClient.ts
new file mode 100644
index 0000000000..708ac4c17b
--- /dev/null
+++ b/src/utils/fetchClient.ts
@@ -0,0 +1,46 @@
+/* eslint-disable @typescript-eslint/no-explicit-any */
+const BASE_URL = 'https://mate.academy/students-api';
+
+// returns a promise resolved after a given delay
+function wait(delay: number) {
+  return new Promise(resolve => {
+    setTimeout(resolve, delay);
+  });
+}
+
+// To have autocompletion and avoid mistypes
+type RequestMethod = 'GET' | 'POST' | 'PATCH' | 'DELETE';
+
+function request<T>(
+  url: string,
+  method: RequestMethod = 'GET',
+  data: any = null, // we can send any data to the server
+): Promise<T> {
+  const options: RequestInit = { method };
+
+  if (data) {
+    // We add body and Content-Type only for the requests with data
+    options.body = JSON.stringify(data);
+    options.headers = {
+      'Content-Type': 'application/json; charset=UTF-8',
+    };
+  }
+
+  // DON'T change the delay it is required for tests
+  return wait(100)
+    .then(() => fetch(BASE_URL + url, options))
+    .then(response => {
+      if (!response.ok) {
+        throw new Error();
+      }
+
+      return response.json();
+    });
+}
+
+export const client = {
+  get: <T>(url: string) => request<T>(url),
+  post: <T>(url: string, data: any) => request<T>(url, 'POST', data),
+  patch: <T>(url: string, data: any) => request<T>(url, 'PATCH', data),
+  delete: (url: string) => request(url, 'DELETE'),
+};