using FluentValidation.Results;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.Serialization;

namespace zero.Core.Entities
{
  [DataContract(Name = "result", Namespace = "")]
  public class EntityResult<T>
  {
    [DataMember(Name = "model")]
    public T Model { get; set; }

    [DataMember(Name = "success")]
    public bool IsSuccess { get; set; }

    [DataMember(Name = "errors")]
    public IList<EntityResultError> Errors { get; set; } = new List<EntityResultError>();

    public EntityResult() { }

    public EntityResult(ValidationResult validation)
    {
      IsSuccess = validation.IsValid;
      Errors = validation.Errors.Select(x => new EntityResultError()
      {
        Property = x.PropertyName,
        Message = x.ErrorMessage
      }).ToList();
    }

    public static EntityResult<T> From<TOrigin>(EntityResult<TOrigin> with, T model = default)
    {
      EntityResult<T> result = new EntityResult<T>();

      result.IsSuccess = with.IsSuccess;
      result.Errors = with.Errors;
      result.Model = model;

      return result;
    }

    public void AddError(string property, string message)
    {
      IsSuccess = false;
      Errors.Add(new EntityResultError()
      {
        Property = property,
        Message = message
      });
    }


    public void AddError(string message)
    {
      IsSuccess = false;
      Errors.Add(new EntityResultError()
      {
        Property = Constants.ErrorFieldNone,
        Message = message
      });
    }


    public EntityResult<T> Combine(EntityResult<T> with)
    {
      if (IsSuccess && !with.IsSuccess)
      {
        IsSuccess = false;
      }
      foreach (EntityResultError error in with.Errors)
      {
        Errors.Add(error);
      }
      return this;
    }


    public static EntityResult<T> Success() => new EntityResult<T>() { IsSuccess = true };

    public static EntityResult<T> Success(T model) => new EntityResult<T>() { IsSuccess = true, Model = model };

    public static EntityResult<T> Fail() => new EntityResult<T>() { };

    public static EntityResult<T> Fail(string property, string message)
    {
      EntityResult<T> result = new EntityResult<T>();
      result.AddError(property, message);
      return result;
    }

    public static EntityResult<T> Fail(string message)
    {
      EntityResult<T> result = new EntityResult<T>();
      result.AddError(message);
      return result;
    }

    public static EntityResult<T> Fail(ValidationResult validation) => new EntityResult<T>(validation);

    public static EntityResult<T> Fail(EntityResultError error) => Fail(error.Property, error.Message);

    public static EntityResult<T> Fail(IEnumerable<EntityResultError> errors) => new EntityResult<T>() { IsSuccess = !errors.Any(), Errors = errors.ToList() };
  }


  public class EntityResult : EntityResult<object>
  {
    public EntityResult() : base() { }

    public EntityResult(ValidationResult validation) : base(validation) { }

    public static EntityResult Maybe(bool isSuccess) => isSuccess ? Success() : Fail();

    public new static EntityResult Success() => new EntityResult() { IsSuccess = true };

    public new static EntityResult Fail() => new EntityResult() { };
  }


  [DataContract(Name = "resultError", Namespace = "")]
  public class EntityResultError
  {
    [DataMember(Name = "property")]
    public string Property { get; set; }

    [DataMember(Name = "message")]
    public string Message { get; set; }
  }
}