import { useState, useRef } from 'react'
import './App.css'

interface Todo {
    id: number,
    text: string,
    completed: boolean
}

type Filter = 'all' | 'active' | 'completed';

function filterTodos(todos: Todo[], filter: Filter): Todo[] {
    switch (filter) {
        case 'all':
            return todos;
        case 'active':
            return todos.filter(todo => !todo.completed);
        case 'completed':
            return todos.filter(todo => todo.completed);
        default:
            return todos;
    }
}
function Header({ addTodo }: { addTodo: (text: string) => void }) {
    const inpRef = useRef<HTMLInputElement>(null);
    const handleKeyDown = (e: React.KeyboardEvent<HTMLInputElement>) => {
        if (e.keyCode === 13) {
            addTodo(inpRef.current!.value);
            inpRef.current!.value = ""
        }
    }
    return (
        <div>
            <header className="header">
                <h1>todos</h1>
                <input
                    ref={inpRef}
                    autoFocus
                    autoComplete="off"
                    placeholder="输入您要完成的任务?"
                    className="new-todo"
                    onKeyDown={handleKeyDown}
                />
            </header>
        </div>
    )
}

function Main({ onToggleAll, allCompleted }: { onToggleAll: (val: boolean) => void, allCompleted: boolean }) {
    const handleToggle = () => {
        allCompleted = !allCompleted;
        onToggleAll(allCompleted)
    }
    return (
        <div>
            <input id="toggle-all" type="checkbox" className="toggle-all" onChange={handleToggle} checked={allCompleted} />
            <label htmlFor="toggle-all"></label>
        </div>
    )
}

function TodoItem({ todo, onDelete, onActive }: { todo: Todo, onDelete: (id: number) => void, onActive: (id: number) => void }) {

    const deleteTodo = (val: number) => {
        onDelete(val)
    }
    const activeTodo = (val: number) => {
        onActive(val)
    }
    return (
        <li className={todo.completed ? 'completed' : ''}>
            <div className="view">
                <input type="checkbox" className="toggle" checked={todo.completed} onChange={() => activeTodo(todo.id)} />
                <label>{todo.text}</label>
                <button className="destroy" onClick={() => deleteTodo(todo.id)}></button>
            </div>
            <input type="text" className="edit" />
        </li>
    )
}

function Footer({ count, clearAll, filter, tabFilter }: { count: number, clearAll: () => void, filter: Filter, tabFilter: (val: string) => void }) {
    console.log(filter, 'filter')
    return (
        <div>
            <span className="todo-count"><strong>{count}</strong> items left </span>
            <ul className="filters">
                <li><a href="#/all" onClick={() => tabFilter('all')} className={filter == 'all' ? 'selected' : ''}>All</a></li>
                <li><a href="#/active" onClick={() => tabFilter('active')} className={filter === 'active' ? 'selected' : ''}>Active</a></li>
                <li><a href="#/completed" onClick={() => tabFilter('completed')} className={filter === 'completed' ? 'selected' : ''}>Completed</a></li>
            </ul>
            <button className="clear-completed" onClick={clearAll}>Clear completed</button>
        </div>
    )
}

function App() {
    const [todos, setTodos] = useState<Todo[]>([
        {
            id: 1, text: '吃饭', completed: false
        },
        {
            id: 2, text: '睡觉', completed: false
        },
        {
            id: 3, text: '打豆豆', completed: true
        }
    ])
    const completeCount = todos.filter((item) => !item.completed).length;
    const isCompleted = todos.every((item) => item.completed);
    const [isFilter, setIsFilter] = useState<Filter>('all');
    const newArr = filterTodos(todos, isFilter);
    const handleAdd = (val: string) => {
        setTodos([...todos, {
            id: Date.now(),
            text: val,
            completed: false
        }])
    }
    const handleDelete = (val: number) => {
        setTodos((prevTodos) => { return prevTodos.filter((todo) => todo.id !== val) })
    }
    const handleAvtive = (val: number) => {
        setTodos((prevTodos) => prevTodos.map((todo) => {
            return todo.id === val ? { ...todo, completed: !todo.completed } : todo
        }))
    }
    const handleAll = (val: boolean) => {
        setTodos((prev) => prev.map((todo) => {
            return { ...todo, completed: val }
        }))
    }
    const handleClear = () => {
        setTodos([...todos.filter((todo) => !todo.completed)])
    }
    const handleSet = (val: Filter) => {
        setIsFilter(val)
    }
    return (
        <>
            <div id="app">
                <section className="todoapp">
                    <Header addTodo={handleAdd}></Header>
                    <section className="main">
                        <Main onToggleAll={handleAll} allCompleted={isCompleted}></Main>
                        <ul className="todo-list">
                            {
                                newArr.map((todo) => {
                                    return (
                                        <TodoItem key={todo.id} todo={todo} onDelete={handleDelete} onActive={handleAvtive}></TodoItem>
                                    )
                                })
                            }
                        </ul>
                    </section>
                    <footer className="footer">
                        <Footer count={completeCount} clearAll={handleClear} filter={isFilter} tabFilter={handleSet}></Footer>
                    </footer>
                </section>
            </div>

        </>
    )
}

export default App