// replayItems - Reads the items from the store and replays.
func replayItems[I any](store Store[I], doneCh <-chan struct{}, log logger, id string) <-chan Key {
	keyCh := make(chan Key)

	go func() {
		defer xioutil.SafeClose(keyCh)

		retryTicker := time.NewTicker(retryInterval)
		defer retryTicker.Stop()

		for {
			for _, key := range store.List() {
				select {
				case keyCh <- key:
				// Get next key.

	if p.offset+p.shardSize > p.shardFileSize {
		p.shardSize = p.shardFileSize - p.offset
	}
	if p.shardSize == 0 {
		return newBuf, nil
	}

	readTriggerCh := make(chan bool, len(p.readers))
	defer xioutil.SafeClose(readTriggerCh) // close the channel upon return

	for i := 0; i < p.dataBlocks; i++ {
		// Setup read triggers for p.dataBlocks number of reads so that it reads in parallel.
		readTriggerCh <- true
	}