using System;
using System.ComponentModel.DataAnnotations;
using System.Reflection;
using System.Web.Mvc;

namespace WX.CRM.Common.MvcValidation
{
    /// <summary>
    /// 两个时间比较，结束时间不能小于开始时间
    /// </summary>
    [AttributeUsage(AttributeTargets.Property, AllowMultiple = false, Inherited = true)]
    public class DateTimeNotLessAttribute : ValidationAttribute, IClientValidatable
    {
        private const string DefaultErrorMessage = "{0}不得小于{1}";
        public string OtherDTProperty { get; private set; }
        private string OtherDTPropertyName { get; set; }

        public DateTimeNotLessAttribute(string otherDTProperty, string otherDTPropertyNamet)
            : base(DefaultErrorMessage)
        {
            if (string.IsNullOrEmpty(otherDTProperty))
            {
                throw new ArgumentNullException("otherDTProperty");
            }

            OtherDTProperty = otherDTProperty;
            OtherDTPropertyName = otherDTPropertyNamet;

        }
        public override string FormatErrorMessage(string name)
        {
            return string.Format(ErrorMessageString, name, OtherDTPropertyName);
        }
        protected override ValidationResult IsValid(object value, ValidationContext validationContext)
        {
            if (value != null)
            {
                PropertyInfo otherDTProperty = validationContext.ObjectInstance.GetType().GetProperty(OtherDTProperty);
                object otherDTPropertyValue = otherDTProperty.GetValue(validationContext.ObjectInstance, null);

                DateTime dtThis = Convert.ToDateTime(value);
                DateTime dtOther = Convert.ToDateTime(otherDTPropertyValue);

                if (dtThis < dtOther)
                {
                    return new ValidationResult(FormatErrorMessage(validationContext.DisplayName));
                }
            }
            return ValidationResult.Success;
        }
        public System.Collections.Generic.IEnumerable<ModelClientValidationRule> GetClientValidationRules(ModelMetadata metadata, ControllerContext context)
        {
            ModelClientValidationRule rule = new ModelClientValidationRule
            {
                ValidationType = "notlessthan",
                ErrorMessage = FormatErrorMessage(metadata.GetDisplayName())
            };
            rule.ValidationParameters.Add("otherproperty", OtherDTProperty);
            yield return rule;
        }

    }
}