using System.Globalization;
using System.Reflection;
using System.Windows.Controls;
using System.Windows.Data;

using BS.Shared.Extensions;

namespace BeWo.Validation
{
    public class AttributeValidator : ValidationRule
    {
        public BindingExpression ExpressionToValidate { get; set; }

        public override ValidationResult Validate(object pValue, CultureInfo pCultureInfo)
        {
            bool lValid = true;

            if (this.ExpressionToValidate != null)
            {
                PropertyInfo lPropInfo = null;
                object lCurrentObject = this.ExpressionToValidate.DataItem;
                if (lCurrentObject != null)
                {
                    foreach (var iPropName in this.ExpressionToValidate.ParentBinding.Path.Path.Split("."))
                    {
                        lPropInfo = lCurrentObject.GetType().GetProperty(iPropName);
                        lCurrentObject = lPropInfo.GetValue(lCurrentObject, null);
                    }
                }

                if (lPropInfo != null)
                {
                    var lAttributes = lPropInfo.GetCustomAttributes(typeof(ValidationAttribute), true);
                    if (lAttributes.Length > 0)
                    {
                        lValid = ((ValidationAttribute) lAttributes[0]).Validate(pValue);
                    }
                }
            }
            
            if (!lValid)
            {
                
            }

// TODO: Nachricht, am besten als Property im ValidationAttribut
            return new ValidationResult(lValid, null);
        }
    }
}