internal void AddSkill(Skill skill , int skillStrength)
{
if(_skills == null)
_skills = new List<ResourceSkill>();
if(!_skills.Select(a=>a.Skill).Contains(skill))
_skills.Add(new ResourceSkill(){Skill = skill , Strength = skillStrength});
}
internal void RemoveSkill(Skill skill)
{
var resSkill = _skills.FirstOrDefault(a => a.Skill.Id == skill.Id);
if (resSkill != null)
_skills.Remove(resSkill);
}