text: import axios from 'axios'
  import React, { useState, useEffect } from 'react'
  import { Link } from 'react-router-dom'
  import { Form, Button } from 'react-bootstrap'
  import { useDispatch, useSelector } from 'react-redux'
  import Message from '../components/Message'
  import Loader from '../components/Loader'
  import FormContainer from '../components/FormContainer'
  import { listProductDetails, updateProduct } from '../actions/productActions'
  import { PRODUCT_UPDATE_RESET } from '../constants/productConstants'
  
  const ProductEditScreen = ({ match, history }) => {
      const productId = match.params.id
  
      const [name, setName] = useState('')
      const [price, setPrice] = useState(0)
      const [image, setImage] = useState('')
      const [brand, setBrand] = useState('')
      const [category, setCategory] = useState('')
      const [countInStock, setCountInStock] = useState(0)
      const [description, setDescription] = useState('')
      const [uploading, setUploading] = useState(false)
  
      const dispatch = useDispatch()
  
      const productDetails = useSelector(state => state.productDetails)
      const { loading, error, product } = productDetails
  
      const productUpdate = useSelector(state => state.productUpdate)
      const { loading: loadingUpdate, error:errorUpdate, success:successUpdate } = productUpdate
  
      useEffect(() => {
          if(successUpdate){
              dispatch({ type: PRODUCT_UPDATE_RESET })
              history.push('/admin/productlist')
          } else {
              if (!product.name || product._id !== productId) {
                  dispatch(listProductDetails(productId))
              } else {
                  setName(product.name)
                  setPrice(product.price)
                  setImage(product.image)
                  setBrand(product.brand)
                  setCategory(product.category)
                  setCountInStock(product.countInStock)
                  setDescription(product.description)
              }
          }
          
  
  
      }, [dispatch, history, productId, product, successUpdate])
  
      const uploadFileHandler = async (e) => {
          const file = e.target.files[0]
          const formData = new FormData()
          formData.append('image', file)
          setUploading(true)
  
          try {
              const config = {
                  headers: {
                      'Content-Type': 'multipart/form-data'
                  }
              }
  
              const { data } = await axios.post('/api/upload', formData, config)
              setImage(data)
              setUploading(false)
          } catch (error){
              console.error(error)
              setUploading(false)
          }
      }
  
      const submitHandler = (e) => {
          e.preventDefault()
          dispatch(updateProduct({
              _id: productId,
              name,
              price, 
              image, 
              brand, 
              category,
              description,
              countInStock
          }))
      }
  
      return (
          <>
              <Link to='/admin/productList' className='btn btn-light my-3'>
                  Go Back
              </Link>
              <FormContainer>
                  <h1>Edit Product</h1>
                  {loadingUpdate && <Loader />}
                  {errorUpdate && <Message variant='danger'>{errorUpdate}</Message>}
                  {loading ? <Loader /> : error ? <Message variant='danger'>{error}</Message> : (
                      <Form onSubmit={submitHandler}>
                          <Form.Group controlId='name'>
                              <Form.Label>Name</Form.Label>
                              <Form.Control
                                  type='name'
                                  placeholder='Enter name'
                                  value={name}
                                  onChange={(e) => setName(e.target.value)}>
                              </Form.Control>
                          </Form.Group>
                          <Form.Group controlId='price'>
                              <Form.Label>Price</Form.Label>
                              <Form.Control
                                  type='number'
                                  placeholder='Enter price'
                                  value={price}
                                  onChange={(e) => setPrice(e.target.value)}>
                              </Form.Control>
                          </Form.Group>
  
                          <Form.Group controlId='image'>
                              <Form.Label>Image</Form.Label>
                              <Form.Control
                                  type='text'
                                  placeholder='Enter image url'
                                  value={image}
                                  onChange={(e) => setImage(e.target.value)}>
                              </Form.Control>
                              <Form.File 
                                  id='image-file' 
                                  label='Choose File' 
                                  custom onChange={uploadFileHandler}>
                              </Form.File>
                              {uploading && <Loader />}
                          </Form.Group>
  
                          <Form.Group controlId='brand'>
                              <Form.Label>Brand</Form.Label>
                              <Form.Control
                                  type='text'
                                  placeholder='Enter brand'
                                  value={brand}
                                  onChange={(e) => setBrand(e.target.value)}>
                              </Form.Control>
                          </Form.Group>
  
                          <Form.Group controlId='countInStock'>
                              <Form.Label>Count In Stock</Form.Label>
                              <Form.Control
                                  type='number'
                                  placeholder='Enter count in stock'
                                  value={countInStock}
                                  onChange={(e) => setCountInStock(e.target.value)}>
                              </Form.Control>
                          </Form.Group>
  
                          <Form.Group controlId='category'>
                              <Form.Label>Category</Form.Label>
                              <Form.Control
                                  type='text'
                                  placeholder='Enter category'
                                  value={category}
                                  onChange={(e) => setCategory(e.target.value)}>
                              </Form.Control>
                          </Form.Group>
  
                          <Form.Group controlId='description'>
                              <Form.Label>Description</Form.Label>
                              <Form.Control
                                  type='text'
                                  placeholder='Enter description'
                                  value={description}
                                  onChange={(e) => setDescription(e.target.value)}>
                              </Form.Control>
                          </Form.Group>
  
  
                          <Button type='submit' vairant='primary'>
                              Update
                          </Button>
                      </Form>
                  )}
              </FormContainer>
          </>
  
      )
  }
  
  export default ProductEditScreen
  