package commands

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

func Lpop(args []string, getShard func(k string) *core.Shard) interface{}{
		key := args[1]
		s := getShard(key)
		item, exists := s.Data[key]
		if !exists {
			return nil
		}
		typedList, ok := item.Value.([]string)
		if !ok {
			return errors.New("WRONGTYPE Operation against a key holding the wrong kind of value")
		}
		if len(typedList) == 0 {
			return nil
		}
		newItem := typedList[0]
		newList := typedList[1:]
		if len(newList) <= 0 {
			delete(s.Data, key)
		} else {
			s.Data[key] = core.Item{Value: newList}
		}
		return newItem
}