using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.ComponentModel.DataAnnotations;
using System.Text.RegularExpressions;
using System.Text;
using Sleis.Models;
using System.Web.Mvc;

namespace Sleis.Validation.Attribute
{
    public class DateValidation : ValidationAttribute
    {   
        public DateValidation()
        {
            if(String.IsNullOrEmpty(base.ErrorMessage))
            {
                base.ErrorMessage = Constants.DateFormatErrorMessage;
            }
        }
        public override bool IsValid(object value)
        {
            //don't worry about being required.  let required attribute handle that
            if (value == null)
            {
                return true;
            }
            /*Removing reged validation since .net converts datetime to its own translation.... using datetime.parseinstead
            Regex regEx = new Regex(Pattern());
            return regEx.IsMatch(value.ToString());
             * */
            DateTime date = new DateTime();
            return DateTime.TryParse(value.ToString(), out date);
        }
         
        public static string Pattern()
        {
            return Constants.DateRegEx;            
        } 
        
    }
    public class DateValidator : DataAnnotationsModelValidator<DateValidation>
    {
        #region Fields

        private readonly string _errorMessage;

        #endregion Fields

        #region Ctors

        /// <summary>
        /// Initializes a new instance of the <see cref="DateValidator"/> class.
        /// </summary>
        /// <param name="metadata">The metadata.</param>
        /// <param name="context">The context.</param>
        /// <param name="attribute">The attribute.</param>
        public DateValidator(ModelMetadata metadata, ControllerContext context, DateValidation attribute)
            : base(metadata, context, attribute)
        {
            this._errorMessage = attribute.ErrorMessage;            
        }

        #endregion Ctors

        #region Methods

        /// <summary>
        /// Retrieves a collection of client validation rules.
        /// </summary>
        /// <returns>A collection of client validation rules.</returns>
        public override IEnumerable<ModelClientValidationRule> GetClientValidationRules()
        {
            var rule = new ModelClientValidationRegexRule(this._errorMessage, DateValidation.Pattern());            
            return new[] { rule };
        }

        #endregion Methods
    }
}