package commands

import (
	"errors"
	"redisClone/pkg/core"
)

func Lpush(args []string, getShard func(k string) *core.Shard) interface{}{
	key := args[1]
	newItems := args[2:]
	s := getShard(key)
	var list []string
	existingItem, exists := s.Data[key]
	if exists {
		var ok bool
		list, ok = existingItem.Value.([]string)
		if !ok {
			return errors.New("WRONGTYPE Operation against a key holding the wrong kind of value")
		}
	} else {
		list = []string{}
	}
	list = append(newItems, list...)
	s.Data[key] = core.Item{Value: list}
	return len(list)
}