import React, { useState, useEffect } from "react";
import axios from "axios";

import AddNewItemForm from "./Form/AddNewItemForm";
import ItemsDisplay from "./Display/ItemsDisplay";
import SummaryDisplay from "./Display/SummaryDisplay";

const BillingPage = () => {
  const [savedItems, getSavedItems] = useState([])

  // get data from server on startup
  useEffect(() => {
    axios.get(`/api/items`)
      .then((res) => {
        getSavedItems(res.data);
      })
      .catch((res) => {
        alert("The promise returned an error idk what to do");
        console.log(res);
      })
  }, []);
  // to be handled by backend
  const defGSTValue = 18;

  // update the items from AddNewItemForm
  const [items, setItems] = useState([]);
  const getItems = (item) => {
    setItems(
      [...items, item]
    );
  };

  return (
    <div>
      <AddNewItemForm savedItems={savedItems} addItem={getItems} defGSTValue={defGSTValue}/>
      <ItemsDisplay items={items} defGSTValue={defGSTValue}/>
      <SummaryDisplay items={items}/>
    </div>
  );
}

export default BillingPage;