public bool isQuestCompleted(int slot_id)
    {
        var _quest = quests[_characterStats.accepted_quests[slot_id]];

        if (_quest.type == quest_types.combat)
        {
            if (_characterStats.isInDefeatedEnemies(_quest.objective))
            {
                return(true);
            }
        }
        else if (_quest.type == quest_types.conversation)
        {
            if (_characterStats.isInCompletedConversations(_quest.objective))
            {
                return(true);
            }
        }
        else if (_quest.type == quest_types.item)
        {
            if (_characterStats.Inventory.Any(a => a == _quest.objective))
            {
                return(true);
            }
        }
        return(false);
    }