import React, { useEffect, useMemo, useState } from 'react';
import {
  IonBadge,
  IonButton,
  IonButtons,
  IonChip,
  IonContent,
  IonHeader,
  IonIcon,
  IonPage,
  IonText,
  IonTitle,
  IonToolbar,
  useIonViewWillEnter,
} from '@ionic/react';
import { addOutline, cartOutline, removeOutline, star } from 'ionicons/icons';
import { RouteComponentProps, useHistory } from 'react-router-dom';
import { CartItem, products, readCart, writeCart } from './Home';
import {
  setStatusBarBackground,
  setStatusBarStyle,
  Style,
} from '../utils/statusBar';

type Props = RouteComponentProps<{ id: string }>;

const ProductDetail: React.FC<Props> = ({ match }) => {
  const history = useHistory();
  const [quantity, setQuantity] = useState(1);
  const [message, setMessage] = useState('');
  const [cartCount, setCartCount] = useState(0);

  useIonViewWillEnter(() => {
    setStatusBarStyle(Style.Dark);
    setStatusBarBackground('#ffffff');
    const count = readCart().reduce((sum, item) => sum + item.quantity, 0);
    setCartCount(count);
  });

  useEffect(() => {
    const syncCount = () => {
      const count = readCart().reduce((sum, item) => sum + item.quantity, 0);
      setCartCount(count);
    };

    syncCount();
    window.addEventListener('storage', syncCount);
    window.addEventListener('cart:updated', syncCount as EventListener);

    return () => {
      window.removeEventListener('storage', syncCount);
      window.removeEventListener('cart:updated', syncCount as EventListener);
    };
  }, []);

  const product = useMemo(
    () => products.find((item) => item.id === match.params.id),
    [match.params.id]
  );

  const showMessage = (text: string) => {
    setMessage(text);
    window.setTimeout(() => setMessage(''), 4000);
  };

  const addToCart = () => {
    if (!product) return;

    const cart: CartItem[] = readCart();
    const existing = cart.find((item) => item.id === product.id);

    const nextCart = existing
      ? cart.map((item) =>
          item.id === product.id
            ? { ...item, quantity: item.quantity + quantity }
            : item
        )
      : [
          ...cart,
          {
            id: product.id,
            name: product.name,
            price: product.price,
            quantity,
          },
        ];

    writeCart(nextCart);
    showMessage('Added to cart');
  };

  if (!product) {
    return (
      <IonPage>
        <IonHeader className="ion-no-border">
          <IonToolbar>
            <IonButtons slot="start">
              <IonButton fill="clear" onClick={() => history.replace('/home')}>
                Back
              </IonButton>
            </IonButtons>
            <IonTitle>Product</IonTitle>
          </IonToolbar>
        </IonHeader>
        <IonContent className="ion-padding">
          <div className="empty-state">
            <h3>Product not found</h3>
            <p className="muted-text">This product is no longer available.</p>
            <IonButton onClick={() => history.replace('/home')}>
              Browse products
            </IonButton>
          </div>
        </IonContent>
      </IonPage>
    );
  }

  return (
    <IonPage>
      <IonHeader className="ion-no-border">
        <IonToolbar>
          <IonButtons slot="start">
            <IonButton fill="clear" onClick={() => history.replace('/home')}>
              Back
            </IonButton>
          </IonButtons>
          <IonTitle>{product.name}</IonTitle>
          <IonButtons slot="end">
            <IonButton
              fill="clear"
              className="cart-button pill-cart-button"
              onClick={() => history.push('/cart')}
            >
              <IonIcon icon={cartOutline} />
              <span>{cartCount}</span>
            </IonButton>
          </IonButtons>
        </IonToolbar>
      </IonHeader>
      <IonContent fullscreen>
        <div className="detail-hero ion-padding">
          <div className="detail-image-wrap">
            <img
              src={product.image}
              alt={product.imageAlt}
              className="detail-image"
            />
          </div>
          <IonChip color="secondary">{product.category}</IonChip>
          <h1>{product.name}</h1>
          <div className="detail-meta">
            <IonBadge color="light">
              <IonIcon icon={star} /> {product.rating}
            </IonBadge>
            <IonBadge color="light">Ready in {product.prepTime}</IonBadge>
          </div>
          <p className="muted-text">{product.description}</p>
          <div className="detail-price">${product.price.toFixed(2)}</div>
        </div>

        <div className="detail-panel ion-padding">
          <h2>Choose quantity</h2>
          <div className="quantity-row">
            <IonButton
              fill="outline"
              onClick={() => setQuantity((value) => Math.max(1, value - 1))}
            >
              <IonIcon icon={removeOutline} />
            </IonButton>
            <span>{quantity}</span>
            <IonButton
              fill="outline"
              onClick={() => setQuantity((value) => value + 1)}
            >
              <IonIcon icon={addOutline} />
            </IonButton>
          </div>

          <div className="order-box">
            <div>
              <IonText color="medium">
                <p>Total</p>
              </IonText>
              <strong>${(product.price * quantity).toFixed(2)}</strong>
            </div>
            <IonButton expand="block" onClick={addToCart}>
              Add to cart
            </IonButton>
          </div>

          {message && (
            <IonText color="success">
              <p>{message}</p>
            </IonText>
          )}

          <IonButton
            fill="clear"
            expand="block"
            onClick={() => history.push('/cart')}
          >
            Go to cart
          </IonButton>
        </div>
      </IonContent>
    </IonPage>
  );
};

export default ProductDetail;