Solution

src/App.tsx

@@ -1,26 +1,305 @@
-/* eslint-disable max-len */
-/* eslint-disable jsx-a11y/control-has-associated-label */
-import React from 'react';
+import React, { useEffect, useMemo, useRef, useState } from 'react';
+import { ErrorNotification } from './components/ErrorNotification';
+import { Footer } from './components/Footer';
+import { Header } from './components/Header';
+import { TodoList } from './components/TodoList';
 import { UserWarning } from './UserWarning';
+import {
+  USER_ID,
+  createTodo,
+  deleteTodo,
+  getTodos,
+  updateTodo,
+} from './api/todos';
+import { Filter } from './types/Filter';
+import { TempTodo } from './types/TempTodo';
+import { Todo } from './types/Todo';
 
-const USER_ID = 0;
+const TEMP_TODO_ID = 0;
+
+const getFilterFromHash = (): Filter => {
+  switch (window.location.hash) {
+    case '#/active':
+      return 'active';
+
+    case '#/completed':
+      return 'completed';
+
+    default:
+      return 'all';
+  }
+};
 
 export const App: React.FC = () => {
+  const [todos, setTodos] = useState<Todo[]>([]);
+  const [filter, setFilter] = useState<Filter>(getFilterFromHash);
+  const [newTodoTitle, setNewTodoTitle] = useState('');
+  const [tempTodo, setTempTodo] = useState<TempTodo | null>(null);
+  const [loadingTodoIds, setLoadingTodoIds] = useState<number[]>([]);
+  const [errorMessage, setErrorMessage] = useState('');
+  const [editingTodoId, setEditingTodoId] = useState<number | null>(null);
+  const [editingTitle, setEditingTitle] = useState('');
+
+  const newTodoField = useRef<HTMLInputElement>(null);
+  const errorTimerId = useRef<number | null>(null);
+  const editingCanceled = useRef(false);
+
+  const hideError = React.useCallback(() => {
+    setErrorMessage('');
+
+    if (errorTimerId.current) {
+      window.clearTimeout(errorTimerId.current);
+      errorTimerId.current = null;
+    }
+  }, []);
+
+  const showError = React.useCallback(
+    (message: string) => {
+      hideError();
+      setErrorMessage(message);
+
+      errorTimerId.current = window.setTimeout(() => {
+        setErrorMessage('');
+        errorTimerId.current = null;
+      }, 3000);
+    },
+    [hideError],
+  );
+
+  const markTodoAsLoading = (todoId: number) => {
+    setLoadingTodoIds(currentIds => [...currentIds, todoId]);
+  };
+
+  const unmarkTodoAsLoading = (todoId: number) => {
+    setLoadingTodoIds(currentIds => currentIds.filter(id => id !== todoId));
+  };
+
+  useEffect(() => {
+    const handleHashChange = () => setFilter(getFilterFromHash());
+
+    window.addEventListener('hashchange', handleHashChange);
+
+    return () => {
+      window.removeEventListener('hashchange', handleHashChange);
+    };
+  }, []);
+
+  useEffect(() => {
+    hideError();
+
+    getTodos()
+      .then(setTodos)
+      .catch(() => showError('Unable to load todos'));
+
+    return () => {
+      if (errorTimerId.current) {
+        window.clearTimeout(errorTimerId.current);
+      }
+    };
+  }, [hideError, showError]);
+
+  useEffect(() => {
+    newTodoField.current?.focus();
+  }, [todos.length, tempTodo, errorMessage]);
+
+  const visibleTodos = useMemo(() => {
+    return todos.filter(todo => {
+      switch (filter) {
+        case 'active':
+          return !todo.completed;
+
+        case 'completed':
+          return todo.completed;
+
+        default:
+          return true;
+      }
+    });
+  }, [todos, filter]);
+
+  const activeTodosCount = todos.filter(todo => !todo.completed).length;
+  const completedTodosCount = todos.length - activeTodosCount;
+  const allTodosCompleted = todos.length > 0 && activeTodosCount === 0;
+  const isAdding = Boolean(tempTodo);
+
+  const handleAddTodo = (event: React.FormEvent) => {
+    event.preventDefault();
+
+    const trimmedTitle = newTodoTitle.trim();
+
+    if (!trimmedTitle) {
+      showError('Title should not be empty');
+
+      return;
+    }
+
+    hideError();
+    setTempTodo({
+      id: TEMP_TODO_ID,
+      userId: USER_ID,
+      title: trimmedTitle,
+      completed: false,
+    });
+
+    createTodo(trimmedTitle)
+      .then(todo => {
+        setTodos(currentTodos => [...currentTodos, todo]);
+        setNewTodoTitle('');
+      })
+      .catch(() => showError('Unable to add a todo'))
+      .finally(() => setTempTodo(null));
+  };
+
+  const handleDeleteTodo = (todoId: number) => {
+    hideError();
+    markTodoAsLoading(todoId);
+
+    return deleteTodo(todoId)
+      .then(() => {
+        setTodos(currentTodos =>
+          currentTodos.filter(todo => todo.id !== todoId),
+        );
+      })
+      .catch(error => {
+        showError('Unable to delete a todo');
+        throw error;
+      })
+      .finally(() => unmarkTodoAsLoading(todoId));
+  };
+
+  const handleUpdateTodo = (todoId: number, data: Partial<Todo>) => {
+    hideError();
+    markTodoAsLoading(todoId);
+
+    return updateTodo(todoId, data)
+      .then(updatedTodo => {
+        setTodos(currentTodos =>
+          currentTodos.map(todo => (todo.id === todoId ? updatedTodo : todo)),
+        );
+      })
+      .catch(error => {
+        showError('Unable to update a todo');
+        throw error;
+      })
+      .finally(() => unmarkTodoAsLoading(todoId));
+  };
+
+  const handleToggleTodo = (todo: Todo) => {
+    handleUpdateTodo(todo.id, { completed: !todo.completed }).catch(() => {});
+  };
+
+  const handleToggleAll = () => {
+    const newCompletedStatus = !allTodosCompleted;
+
+    todos
+      .filter(todo => todo.completed !== newCompletedStatus)
+      .forEach(todo => {
+        handleUpdateTodo(todo.id, { completed: newCompletedStatus }).catch(
+          () => {},
+        );
+      });
+  };
+
+  const startEditing = (todo: Todo | TempTodo) => {
+    if (todo.id === TEMP_TODO_ID) {
+      return;
+    }
+
+    editingCanceled.current = false;
+    setEditingTodoId(todo.id);
+    setEditingTitle(todo.title);
+  };
+
+  const cancelEditing = () => {
+    editingCanceled.current = true;
+    setEditingTodoId(null);
+    setEditingTitle('');
+  };
+
+  const submitTodoTitle = (todo: Todo) => {
+    if (editingCanceled.current) {
+      editingCanceled.current = false;
+
+      return;
+    }
+
+    const trimmedTitle = editingTitle.trim();
+
+    if (trimmedTitle === todo.title) {
+      cancelEditing();
+
+      return;
+    }
+
+    if (!trimmedTitle) {
+      handleDeleteTodo(todo.id)
+        .then(cancelEditing)
+        .catch(() => {});
+
+      return;
+    }
+
+    handleUpdateTodo(todo.id, { title: trimmedTitle })
+      .then(cancelEditing)
+      .catch(() => {});
+  };
+
+  const handleClearCompleted = () => {
+    todos
+      .filter(todo => todo.completed)
+      .forEach(todo => {
+        handleDeleteTodo(todo.id).catch(() => {});
+      });
+  };
+
   if (!USER_ID) {
     return <UserWarning />;
   }
 
   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
+          todosCount={todos.length}
+          allTodosCompleted={allTodosCompleted}
+          newTodoTitle={newTodoTitle}
+          isAdding={isAdding}
+          newTodoField={newTodoField}
+          onAddTodo={handleAddTodo}
+          onNewTodoTitleChange={setNewTodoTitle}
+          onToggleAll={handleToggleAll}
+        />
+
+        {(todos.length > 0 || tempTodo) && (
+          <TodoList
+            todos={visibleTodos}
+            tempTodo={tempTodo}
+            tempTodoId={TEMP_TODO_ID}
+            loadingTodoIds={loadingTodoIds}
+            editingTodoId={editingTodoId}
+            editingTitle={editingTitle}
+            onToggleTodo={handleToggleTodo}
+            onDeleteTodo={todoId => handleDeleteTodo(todoId).catch(() => {})}
+            onStartEditing={startEditing}
+            onEditingTitleChange={setEditingTitle}
+            onCancelEditing={cancelEditing}
+            onSubmitTodoTitle={submitTodoTitle}
+          />
+        )}
+
+        {todos.length > 0 && (
+          <Footer
+            activeTodosCount={activeTodosCount}
+            completedTodosCount={completedTodosCount}
+            filter={filter}
+            onClearCompleted={handleClearCompleted}
+          />
+        )}
+      </div>
+
+      <ErrorNotification errorMessage={errorMessage} onHideError={hideError} />
+    </div>
   );
 };

src/api/todos.ts

@@ -0,0 +1,24 @@
+import { Todo } from '../types/Todo';
+import { client } from '../utils/fetchClient';
+
+export const USER_ID = 4351;
+
+export const getTodos = () => {
+  return client.get<Todo[]>(`/todos?userId=${USER_ID}`);
+};
+
+export const createTodo = (title: string) => {
+  return client.post<Todo>('/todos', {
+    userId: USER_ID,
+    title,
+    completed: false,
+  });
+};
+
+export const deleteTodo = (todoId: number) => {
+  return client.delete(`/todos/${todoId}`);
+};
+
+export const updateTodo = (todoId: number, data: Partial<Todo>) => {
+  return client.patch<Todo>(`/todos/${todoId}`, data);
+};

src/components/ErrorNotification.tsx

@@ -0,0 +1,27 @@
+/* eslint-disable jsx-a11y/control-has-associated-label */
+import React from 'react';
+
+type Props = {
+  errorMessage: string;
+  onHideError: () => void;
+};
+
+export const ErrorNotification: React.FC<Props> = ({
+  errorMessage,
+  onHideError,
+}) => (
+  <div
+    data-cy="ErrorNotification"
+    className={`notification is-danger is-light has-text-weight-normal ${
+      errorMessage ? '' : 'hidden'
+    }`}
+  >
+    <button
+      data-cy="HideErrorButton"
+      type="button"
+      className="delete"
+      onClick={onHideError}
+    />
+    {errorMessage}
+  </div>
+);