text: /*
   * Copyright (c) 2021 Anton Bagdatyev (Tonix)
   *
   * Permission is hereby granted, free of charge, to any person
   * obtaining a copy of this software and associated documentation
   * files (the "Software"), to deal in the Software without
   * restriction, including without limitation the rights to use,
   * copy, modify, merge, publish, distribute, sublicense, and/or sell
   * copies of the Software, and to permit persons to whom the
   * Software is furnished to do so, subject to the following
   * conditions:
   *
   * The above copyright notice and this permission notice shall be
   * included in all copies or substantial portions of the Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
   * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
   * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
   * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
   * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
   * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
   * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
   * OTHER DEALINGS IN THE SOFTWARE.
   */
  
  import { useState, useMemo } from "react";
  import { partialShallowEqual } from "js-utl";
  
  /**
   * Hook to use a POJO state which merges values of the previous state with the next one
   * if the partial state update of the next state is not the same as the previous state
   * for the same keys.
   *
   * @param {Object|Function} initialState The initial state, either a POJO (Plain Old JavaScript Object)
   *                                       or a function returning a POJO (lazy initial state).
   * @return {Array} A tuple of two values, current state POJO and callback to set state,
   *                 like the one returned by the "useState" hook.
   *
   *                 The callback to set state may receive an updater function which will receive
   *                 the previous POJO state as argument and must return the next partial POJO state
   *                 update or "null" (to bail out of the state update, read below).
   *
   *                 If the updater function returns "null" or a partial POJO state update which
   *                 has the same values for the same keys as the current POJO state, the update will be
   *                 bailed out as for the "useState" hook.
   */
  export default function usePOJOState(initialState) {
    const [state, setState] = useState(initialState);
    const setPOJOState = useMemo(
      () => nextState =>
        setState(prevState => {
          const newState =
            typeof nextState === "function" ? nextState(prevState) : nextState;
          if (newState === null) {
            return prevState;
          } else {
            return partialShallowEqual(prevState, newState)
              ? prevState
              : { ...prevState, ...newState };
          }
        }),
      []
    );
    return [state, setPOJOState];
  }
  