import { useCallback, useRef } from 'react';
/**
 * A React hook that allows you to queue up functions to be executed in order.
 * This is useful when you need to ensure long running networks requests are processed sequentially.
 * Builds up a "queue" of functions to be executed in order, only ever processing the last function in the queue.
 * This ensures that a long queue of tasks doesn't cause a backlog of tasks to be processed.
 * E.g. if you queue a task and it begins running, then you queue 9 more tasks:
 *   1. The currently task will finish
 *   2. The next task in the queue will run
 *   3. All remaining tasks will be discarded
 * @returns {queueTask} A function used to queue a function.
 * @example
 * const { queueTask } = useQueue()
 * queueTask(async () => {
 *   await fetch('https://api.example.com')
 * })
 */
export function useQueue() {
  const queue = useRef([]);
  const isProcessing = useRef(false);
  const queueTask = useCallback((fn, options) => {
    queue.current.push(fn);
    async function processQueue() {
      if (isProcessing.current) {
        return;
      }
      // Allow the consumer to prevent the queue from processing under certain conditions
      if (typeof options?.beforeProcess === 'function') {
        const shouldContinue = options.beforeProcess();
        if (shouldContinue === false) {
          return;
        }
      }
      while (queue.current.length > 0) {
        const latestTask = queue.current.pop() // Only process the last task in the queue
;
        queue.current = []; // Discard all other tasks
        isProcessing.current = true;
        try {
          await latestTask();
        } catch (err) {
          console.error('Error in queued function:', err); // eslint-disable-line no-console
        } finally {
          isProcessing.current = false;
          if (typeof options?.afterProcess === 'function') {
            options.afterProcess();
          }
        }
      }
    }
    void processQueue();
  }, []);
  return {
    queueTask
  };
}
//# sourceMappingURL=useQueue.js.map