diff --git a/src/App.tsx b/src/App.tsx
index a399287bd..56e919b39 100644
--- a/src/App.tsx
+++ b/src/App.tsx
@@ -1,5 +1,8 @@
 /* eslint-disable jsx-a11y/control-has-associated-label */
 import React from 'react';
+import { Header } from './components/Header';
+import { TodoList } from './components/TodoList';
+import { Footer } from './components/Footer';
 
 export const App: React.FC = () => {
   return (
@@ -7,150 +10,9 @@ export const App: React.FC = () => {
       <h1 className="todoapp__title">todos</h1>
 
       <div className="todoapp__content">
-        <header className="todoapp__header">
-          {/* this button should have `active` class only if all todos are completed */}
-          <button
-            type="button"
-            className="todoapp__toggle-all active"
-            data-cy="ToggleAllButton"
-          />
-
-          {/* Add a todo on form submit */}
-          <form>
-            <input
-              data-cy="NewTodoField"
-              type="text"
-              className="todoapp__new-todo"
-              placeholder="What needs to be done?"
-            />
-          </form>
-        </header>
-
-        <section className="todoapp__main" data-cy="TodoList">
-          {/* This is a completed todo */}
-          <div data-cy="Todo" className="todo completed">
-            <label className="todo__status-label">
-              <input
-                data-cy="TodoStatus"
-                type="checkbox"
-                className="todo__status"
-                checked
-              />
-            </label>
-
-            <span data-cy="TodoTitle" className="todo__title">
-              Completed Todo
-            </span>
-
-            {/* Remove button appears only on hover */}
-            <button type="button" className="todo__remove" data-cy="TodoDelete">
-              ×
-            </button>
-          </div>
-
-          {/* This todo is an active todo */}
-          <div data-cy="Todo" className="todo">
-            <label className="todo__status-label">
-              <input
-                data-cy="TodoStatus"
-                type="checkbox"
-                className="todo__status"
-              />
-            </label>
-
-            <span data-cy="TodoTitle" className="todo__title">
-              Not Completed Todo
-            </span>
-
-            <button type="button" className="todo__remove" data-cy="TodoDelete">
-              ×
-            </button>
-          </div>
-
-          {/* This todo is being edited */}
-          <div data-cy="Todo" className="todo">
-            <label className="todo__status-label">
-              <input
-                data-cy="TodoStatus"
-                type="checkbox"
-                className="todo__status"
-              />
-            </label>
-
-            {/* This form is shown instead of the title and remove button */}
-            <form>
-              <input
-                data-cy="TodoTitleField"
-                type="text"
-                className="todo__title-field"
-                placeholder="Empty todo will be deleted"
-                value="Todo is being edited now"
-              />
-            </form>
-          </div>
-
-          {/* This todo is in loadind state */}
-          <div data-cy="Todo" className="todo">
-            <label className="todo__status-label">
-              <input
-                data-cy="TodoStatus"
-                type="checkbox"
-                className="todo__status"
-              />
-            </label>
-
-            <span data-cy="TodoTitle" className="todo__title">
-              Todo is being saved now
-            </span>
-
-            <button type="button" className="todo__remove" data-cy="TodoDelete">
-              ×
-            </button>
-          </div>
-        </section>
-
-        {/* Hide the footer if there are no todos */}
-        <footer className="todoapp__footer" data-cy="Footer">
-          <span className="todo-count" data-cy="TodosCounter">
-            3 items left
-          </span>
-
-          {/* Active link should have the 'selected' class */}
-          <nav className="filter" data-cy="Filter">
-            <a
-              href="#/"
-              className="filter__link selected"
-              data-cy="FilterLinkAll"
-            >
-              All
-            </a>
-
-            <a
-              href="#/active"
-              className="filter__link"
-              data-cy="FilterLinkActive"
-            >
-              Active
-            </a>
-
-            <a
-              href="#/completed"
-              className="filter__link"
-              data-cy="FilterLinkCompleted"
-            >
-              Completed
-            </a>
-          </nav>
-
-          {/* this button should be disabled if there are no completed todos */}
-          <button
-            type="button"
-            className="todoapp__clear-completed"
-            data-cy="ClearCompletedButton"
-          >
-            Clear completed
-          </button>
-        </footer>
+        <Header />
+        <TodoList />
+        <Footer />
       </div>
     </div>
   );
diff --git a/src/GlobalProvider.tsx b/src/GlobalProvider.tsx
new file mode 100644
index 000000000..0d7e1e655
--- /dev/null
+++ b/src/GlobalProvider.tsx
@@ -0,0 +1,67 @@
+import { Action } from './types/Action';
+import { Filter } from './types/Filter';
+import { State } from './types/State';
+import { useEffect, useReducer } from 'react';
+import React from 'react';
+
+const reducer = (state: State, action: Action): State => {
+  switch (action.type) {
+    case 'addTodo':
+      return {
+        ...state,
+        todos: [...state.todos, action.payload],
+      };
+
+    case 'deleteTodo':
+      return {
+        ...state,
+        todos: state.todos.filter(todo => todo.id !== action.payload),
+      };
+
+    case 'updateTodo':
+      return {
+        ...state,
+        todos: state.todos.map(todo =>
+          todo.id === action.payload.id ? action.payload : todo,
+        ),
+      };
+
+    case 'setFilter':
+      return {
+        ...state,
+        filter: action.payload,
+      };
+
+    default:
+      return state;
+  }
+};
+
+const loadedTodos = localStorage.getItem('todos');
+const initialState: State = {
+  todos: loadedTodos ? JSON.parse(loadedTodos) : [],
+  filter: Filter.All,
+};
+
+export const StateContext = React.createContext<State>(initialState);
+export const DispatchContext = React.createContext<React.Dispatch<Action>>(
+  () => {},
+);
+
+type Props = {
+  children: React.ReactNode;
+};
+
+export const GlobalProvider: React.FC<Props> = ({ children }) => {
+  const [state, dispatch] = useReducer(reducer, initialState);
+
+  useEffect(() => {
+    localStorage.setItem('todos', JSON.stringify(state.todos));
+  }, [state.todos]);
+
+  return (
+    <DispatchContext.Provider value={dispatch}>
+      <StateContext.Provider value={state}>{children}</StateContext.Provider>
+    </DispatchContext.Provider>
+  );
+};
diff --git a/src/components/Footer.tsx b/src/components/Footer.tsx
new file mode 100644
index 000000000..17c4c1cad
--- /dev/null
+++ b/src/components/Footer.tsx
@@ -0,0 +1,64 @@
+import { useContext, useMemo } from 'react';
+import { DispatchContext, StateContext } from '../GlobalProvider';
+import { Filter } from '../types/Filter';
+import classNames from 'classnames';
+
+export const Footer = () => {
+  const { todos, filter } = useContext(StateContext);
+  const dispatch = useContext(DispatchContext);
+
+  const activeTodosCount = useMemo(
+    () => todos.filter(todo => !todo.completed).length,
+    [todos],
+  );
+
+  const deleteCompleted = () => {
+    todos.forEach(todo => {
+      if (todo.completed) {
+        dispatch({ type: 'deleteTodo', payload: todo.id });
+      }
+    });
+  };
+
+  if (!todos.length) {
+    return;
+  }
+
+  return (
+    <>
+      <footer className="todoapp__footer" data-cy="Footer">
+        <span className="todo-count" data-cy="TodosCounter">
+          {`${activeTodosCount} items left`}
+        </span>
+
+        <nav className="filter" data-cy="Filter">
+          {Object.values(Filter).map(currFilter => (
+            <a
+              href={`#/${currFilter === Filter.All ? '' : currFilter.toLowerCase()}`}
+              className={classNames('filter__link', {
+                selected: currFilter === filter,
+              })}
+              data-cy={`FilterLink${currFilter}`}
+              key={currFilter}
+              onClick={() => {
+                dispatch({ type: 'setFilter', payload: currFilter });
+              }}
+            >
+              {currFilter}
+            </a>
+          ))}
+        </nav>
+
+        <button
+          type="button"
+          className="todoapp__clear-completed"
+          data-cy="ClearCompletedButton"
+          disabled={activeTodosCount === todos.length}
+          onClick={deleteCompleted}
+        >
+          Clear completed
+        </button>
+      </footer>
+    </>
+  );
+};
diff --git a/src/components/Header.tsx b/src/components/Header.tsx
new file mode 100644
index 000000000..454226db5
--- /dev/null
+++ b/src/components/Header.tsx
@@ -0,0 +1,92 @@
+import { useContext, useEffect, useMemo, useRef, useState } from 'react';
+import { Todo } from '../types/Todo';
+import classNames from 'classnames';
+import { DispatchContext, StateContext } from '../GlobalProvider';
+
+
+export const Header = () => {
+  const [title, setTitle] = useState('');
+
+  const titleField = useRef<HTMLInputElement>(null);
+
+  const { todos } = useContext(StateContext);
+  const dispatch = useContext(DispatchContext);
+
+  useEffect(() => {
+    if (titleField.current) {
+      titleField.current.focus();
+    }
+  }, [todos.length]);
+
+  const handleSubmit = (e: React.FormEvent) => {
+    e.preventDefault();
+
+    if (!title.trim()) {
+      return;
+    }
+
+    const newTodo: Todo = {
+      id: +Date.now(),
+      title: title.trim(),
+      completed: false,
+    };
+
+    dispatch({ type: 'addTodo', payload: newTodo });
+    setTitle('');
+  };
+
+  const handleTitleChange = (e: React.ChangeEvent<HTMLInputElement>) => {
+    setTitle(e.target.value);
+  };
+
+  const allTodosCompleted = useMemo(() => {
+    return todos.filter(todo => todo.completed).length === todos.length;
+  }, [todos]);
+
+  const handleToggleAllButtonClick = () => {
+    let todosToChange = [];
+
+    if (allTodosCompleted) {
+      todosToChange = [...todos];
+    } else {
+      todosToChange = todos.filter(todo => !todo.completed);
+    }
+
+    todosToChange.forEach(todo => {
+      const { id, title: todoTitle, completed } = todo;
+
+      dispatch({
+        type: 'updateTodo',
+        payload: { id, title: todoTitle, completed: !completed },
+      });
+    });
+  };
+
+  return (
+    <header className="todoapp__header">
+      {!!todos.length && (
+        <button
+          type="button"
+          className={classNames('todoapp__toggle-all', {
+            active: allTodosCompleted,
+          })}
+          data-cy="ToggleAllButton"
+          onClick={handleToggleAllButtonClick}
+        />
+      )}
+
+      <form onSubmit={handleSubmit}>
+        <input
+          ref={titleField}
+          data-cy="NewTodoField"
+          type="text"
+          className="todoapp__new-todo"
+          placeholder="What needs to be done?"
+          value={title}
+          onChange={handleTitleChange}
+          autoFocus
+        />
+      </form>
+    </header>
+  );
+};
diff --git a/src/components/TodoItem.tsx b/src/components/TodoItem.tsx
new file mode 100644
index 000000000..021685c1e
--- /dev/null
+++ b/src/components/TodoItem.tsx
@@ -0,0 +1,111 @@
+import classNames from 'classnames';
+import { Todo } from '../types/Todo';
+import { useContext, useState } from 'react';
+import { DispatchContext } from '../GlobalProvider';
+
+type Props = {
+  todo: Todo;
+};
+
+/* eslint-disable jsx-a11y/label-has-associated-control */
+export const TodoItem: React.FC<Props> = ({ todo }) => {
+  const { id, title, completed } = todo;
+
+  const [isEditing, setIsEditing] = useState(false);
+  const [editedTitle, setEditedTitle] = useState(title);
+
+  const dispatch = useContext(DispatchContext);
+
+  const handleEditedTitleChange = (e: React.ChangeEvent<HTMLInputElement>) => {
+    setEditedTitle(e.target.value);
+  };
+
+  const saveChanges = () => {
+    const trimmedEditedTitle = editedTitle.trim();
+
+    if (!trimmedEditedTitle) {
+      dispatch({ type: 'deleteTodo', payload: id });
+      setIsEditing(false);
+
+      return;
+    }
+
+    dispatch({
+      type: 'updateTodo',
+      payload: { id, title: trimmedEditedTitle, completed },
+    });
+    setIsEditing(false);
+  };
+
+  const handleEditSubmit = (e: React.FormEvent) => {
+    e.preventDefault();
+    saveChanges();
+  };
+
+  const handleEscapeKeyUp = (e: React.KeyboardEvent) => {
+    if (e.key === 'Escape') {
+      setIsEditing(false);
+    }
+  };
+
+  return (
+    <>
+      {/* This is a completed todo */}
+      <div
+        data-cy="Todo"
+        className={classNames('todo', { completed: completed })}
+        key={id}
+      >
+        <label className="todo__status-label">
+          <input
+            data-cy="TodoStatus"
+            type="checkbox"
+            className="todo__status"
+            checked={completed}
+            onChange={() =>
+              dispatch({
+                type: 'updateTodo',
+                payload: { id, title, completed: !completed },
+              })
+            }
+          />
+        </label>
+
+        {isEditing ? (
+          <form onSubmit={handleEditSubmit}>
+            <input
+              data-cy="TodoTitleField"
+              type="text"
+              className="todo__title-field"
+              placeholder="Empty todo will be deleted"
+              value={editedTitle}
+              onChange={handleEditedTitleChange}
+              onBlur={saveChanges}
+              onKeyUp={handleEscapeKeyUp}
+              autoFocus
+            />
+          </form>
+        ) : (
+          <>
+            <span
+              data-cy="TodoTitle"
+              className="todo__title"
+              onDoubleClick={() => setIsEditing(true)}
+            >
+              {title}
+            </span>
+
+            <button
+              type="button"
+              className="todo__remove"
+              data-cy="TodoDelete"
+              onClick={() => dispatch({ type: 'deleteTodo', payload: id })}
+            >
+              ×
+            </button>
+          </>
+        )}
+      </div>
+    </>
+  );
+};
diff --git a/src/components/TodoList.tsx b/src/components/TodoList.tsx
new file mode 100644
index 000000000..05462a368
--- /dev/null
+++ b/src/components/TodoList.tsx
@@ -0,0 +1,26 @@
+import { useContext, useMemo } from 'react';
+import { StateContext } from '../GlobalProvider';
+import { TodoItem } from './TodoItem';
+import { filterTodos } from '../utils/filterTodos';
+
+/* eslint-disable jsx-a11y/label-has-associated-control */
+export const TodoList = () => {
+  const { todos, filter } = useContext(StateContext);
+
+  const visibleTodos = useMemo(
+    () => filterTodos(todos, filter),
+    [filter, todos],
+  );
+
+  if (!todos.length) {
+    return null;
+  }
+
+  return (
+    <section className="todoapp__main" data-cy="TodoList">
+      {visibleTodos.map(todo => (
+        <TodoItem todo={todo} key={todo.id} />
+      ))}
+    </section>
+  );
+};
diff --git a/src/index.tsx b/src/index.tsx
index a9689cb38..22acad026 100644
--- a/src/index.tsx
+++ b/src/index.tsx
@@ -1,11 +1,12 @@
 import { createRoot } from 'react-dom/client';
-
-import './styles/index.css';
-import './styles/todo-list.css';
-import './styles/filters.css';
-
+import './styles/index.scss';
 import { App } from './App';
+import { GlobalProvider } from './GlobalProvider';
 
 const container = document.getElementById('root') as HTMLDivElement;
 
-createRoot(container).render(<App />);
+createRoot(container).render(
+  <GlobalProvider>
+    <App />
+  </GlobalProvider>,
+);
diff --git a/src/styles/todo.scss b/src/styles/todo.scss
index 4576af434..cfb34ec2f 100644
--- a/src/styles/todo.scss
+++ b/src/styles/todo.scss
@@ -71,6 +71,7 @@
   }
 
   &__title-field {
+    box-sizing: border-box;
     width: 100%;
     padding: 11px 14px;
 
diff --git a/src/styles/todoapp.scss b/src/styles/todoapp.scss
index e289a9458..29383a1e2 100644
--- a/src/styles/todoapp.scss
+++ b/src/styles/todoapp.scss
@@ -56,6 +56,7 @@
   }
 
   &__new-todo {
+    box-sizing: border-box;
     width: 100%;
     padding: 16px 16px 16px 60px;
 
diff --git a/src/types/Action.ts b/src/types/Action.ts
new file mode 100644
index 000000000..d56bc7e12
--- /dev/null
+++ b/src/types/Action.ts
@@ -0,0 +1,8 @@
+import { Filter } from './Filter';
+import { Todo } from './Todo';
+
+export type Action =
+  | { type: 'addTodo'; payload: Todo }
+  | { type: 'deleteTodo'; payload: number }
+  | { type: 'updateTodo'; payload: Todo }
+  | { type: 'setFilter'; payload: Filter };
diff --git a/src/types/Filter.ts b/src/types/Filter.ts
new file mode 100644
index 000000000..66887875b
--- /dev/null
+++ b/src/types/Filter.ts
@@ -0,0 +1,5 @@
+export enum Filter {
+  All = 'All',
+  Active = 'Active',
+  Completed = 'Completed',
+}
diff --git a/src/types/State.ts b/src/types/State.ts
new file mode 100644
index 000000000..d8f8851e2
--- /dev/null
+++ b/src/types/State.ts
@@ -0,0 +1,7 @@
+import { Filter } from './Filter';
+import { Todo } from './Todo';
+
+export interface State {
+  todos: Todo[];
+  filter: Filter;
+}
diff --git a/src/types/Todo.ts b/src/types/Todo.ts
new file mode 100644
index 000000000..f9e06b381
--- /dev/null
+++ b/src/types/Todo.ts
@@ -0,0 +1,5 @@
+export interface Todo {
+  id: number;
+  title: string;
+  completed: boolean;
+}
diff --git a/src/utils/filterTodos.ts b/src/utils/filterTodos.ts
new file mode 100644
index 000000000..7658b1668
--- /dev/null
+++ b/src/utils/filterTodos.ts
@@ -0,0 +1,15 @@
+import { Filter } from '../types/Filter';
+import { Todo } from '../types/Todo';
+
+export const filterTodos = (todos: Todo[], filterBy: Filter): Todo[] => {
+  switch (filterBy) {
+    case Filter.Completed:
+      return todos.filter(todo => todo.completed);
+
+    case Filter.Active:
+      return todos.filter(todo => !todo.completed);
+
+    default:
+      return todos;
+  }
+};