react - usearray() custom hook example

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import React, { useState, useMemo } from 'react';

// ----------------------

// Read more here:  https://dirask.com/snippets/jmJNN1
//
const useProxy = (action) => {
    const state = useMemo(
        () => ({
            wrapper: (...args) => {
                if (state.action) {
                    return state.action(...args);
                }
                return undefined;
            }
        }),
        []
    );
    state.action = action;
    return state.wrapper;
};

// ----------------------

// Read more here:  https://dirask.com/snippets/D7XEop

const prependItem = (updater, item) => {
    updater(array => [].concat(item, array));
};

const appendItem = (updater, item) => {
    updater(array => [].concat(array, item));
};
  
const replaceItem = (updater, index, item) => {
    updater(array => array.map((value, i) => i === index ? item : value));
};

const removeItem = (updater, index) => {
    updater(array => array.filter((value, i) => i !== index));
};

// ----------------------

const useArray = (initialArray = []) => {
    const [items, setItems] = useState(initialArray);
    return {
        getItems:    useProxy(()            => items),
        setItems:    useProxy((items)       => setItems(items)),
        prependItem: useProxy((item)        => prependItem(setItems, item)),
        appendItem:  useProxy((item)        => appendItem(setItems, item)),
        replaceItem: useProxy((index, item) => replaceItem(setItems, index, item)),
        removeItem:  useProxy((index, item) => removeItem(setItems, index)),
        isEmpty:     useProxy(()            => items.length === 0),
    };
};

// ----------------------


// Usage example:

let counter = 0;

const App = () => {
    const array = useArray([]);
    const handlePrependClick = () => array.prependItem((++counter) + '-prepended');
    const handleAppendedClick = () => array.appendItem((++counter) + '-appended ');
    const items = array.getItems();
    return (
        <div>
          <div>
            <button onClick={handlePrependClick}>Prepend</button>
          </div>
          <br />
          <pre style={{border: '1px solid silver'}}>
            {items.map((item, index) => {
                const handleReplaceClick = () => array.replaceItem(index, (++counter) + '-replaced ');
                const handleRemoveClick = () => array.removeItem(index);
                return (
                    <div key={item}>
                      <span>{item}</span>
                      {' '}
                      <button onClick={handleReplaceClick}>Replace</button>
                      <button onClick={handleRemoveClick}>Remove</button>
                    </div>
                );
            })}  
          </pre>
          <br />
          <div>
            <button onClick={handleAppendedClick}>Append</button>
          </div>
        </div >
    );
};

export default App;