using AutoMapper;

using Newtonsoft.Json;

using System;

public class Program

{

    public static void Main()

    {

        IMapper mapper = new MapperConfiguration(cfg => cfg.AddProfile<MappingProfile>())

            .CreateMapper();

        mapper.ConfigurationProvider.AssertConfigurationIsValid();

        Console.WriteLine("mapper.ConfigurationProvider.AssertConfigurationIsValid();");

        Console.WriteLine();

        Console.WriteLine("-- Create a domain model --");

        var emailTask = new EmailTask(

            1, 

            new DateTime(2021, 2, 18),

            new Email("test@email.com", "test subject", "test body"), 

            null, 

            false, 

            EmailTaskStatus.Unsent

        );

        Console.WriteLine(emailTask);

        Console.WriteLine();

        Console.WriteLine("-- Mapping from domain model to dbo --");

        var emailDbo = mapper.Map<EmailDbo>(emailTask);

        Console.WriteLine(emailDbo);

        Console.WriteLine();

        Console.WriteLine("-- Mapping from dbo back to domain model --");

        var emailTask2 = mapper.Map<EmailTask>(emailDbo);

        Console.WriteLine(emailTask2);

    }

    // Domain models

    public class Email

    {

        public string SendTo { get; private set; }

        public string Subject { get; private set; }

        public string Body { get; private set; }

        public DateTime? DateSent { get; private set; }

        public Email(string sendTo, string subject, string body, DateTime? dateSent = null)

        {

            // Validations

            this.SendTo = sendTo;

            this.Subject = subject;

            this.Body = body;

            this.DateSent = dateSent;

        }

    }

    public enum EmailTaskStatus

    {

        Sent = 1,

        Unsent = 2

    }

    public class EmailTask

    {

        public int Id { get; private set; }

        public DateTime DateCreated { get; private set; }

        public Email PayerEmail { get; private set; }

        public Email AdminEmail { get; private set; }

        public bool DownloadAvailableForAdmin { get; private set; }

        public EmailTaskStatus Status { get; private set; }

        public EmailTask(int emailId, DateTime dateCreated, Email payerEmail, Email adminEmail,

            bool downloadAvailable, EmailTaskStatus status)

        {

            // Validations

            this.Id = emailId;

            this.DateCreated = dateCreated;

            this.PayerEmail = payerEmail;

            this.AdminEmail = adminEmail;

            this.DownloadAvailableForAdmin = downloadAvailable;

            this.Status = status;

        }

        public override string ToString()

        {

            return JsonConvert.SerializeObject(this, Formatting.Indented);

        }

    }

    // Database objects, aka dbo

    public class EmailDbo

    {

        public int EmailId { get; set; }

        public DateTime DateCreated { get; set; }

        public DateTime? DateSent { get; set; }

        public string SendTo { get; set; }

        public string Subject { get; set; }

        public string Body { get; set; }

        public bool DownloadAvailable { get; set; }

        public DateTime? AdminDateSent { get; set; }

        public string AdminEmail { get; set; }

        public string AdminSubject { get; set; }

        public string AdminBody { get; set; }

        public int StatusId { get; set; }

        public override string ToString()

        {

            return JsonConvert.SerializeObject(this, Formatting.Indented);

        }

    }

    // Mappings

    public class MappingProfile : Profile

    {

        public MappingProfile()

        {

            CreateMap<EmailTask, EmailDbo>()

                .ForMember(dest => dest.EmailId, opts => opts.MapFrom(src => src.Id))

                .ForMember(dest => dest.SendTo, opts => opts.MapFrom(src => src.PayerEmail.SendTo))

                .ForMember(dest => dest.Subject, opts => opts.MapFrom(src => src.PayerEmail.Subject))

                .ForMember(dest => dest.Body, opts => opts.MapFrom(src => src.PayerEmail.Body))

                .ForMember(dest => dest.DateSent, opts => opts.MapFrom(src => src.PayerEmail.DateSent))

                .ForMember(dest => dest.DownloadAvailable, opts => opts.MapFrom(src => src.DownloadAvailableForAdmin))

                .ForMember(dest => dest.AdminEmail, opts => 

                {

                    opts.PreCondition(src => (src.AdminEmail != null));

                    opts.MapFrom(src => src.AdminEmail.SendTo);

                })

                .ForMember(dest => dest.AdminSubject, opts =>

                {

                    opts.PreCondition(src => (src.AdminEmail != null));

                    opts.MapFrom(src => src.AdminEmail.Subject);

                })

                .ForMember(dest => dest.AdminBody, opts =>

                {

                    opts.PreCondition(src => (src.AdminEmail != null));

                    opts.MapFrom(src => src.AdminEmail.Body);   

                })

                .ForMember(dest => dest.AdminDateSent, opts =>

                {

                    opts.PreCondition(src => (src.AdminEmail != null)); 

                    opts.MapFrom(src => src.AdminEmail.DateSent);   

                })

                .ForMember(dest => dest.StatusId, opts => opts.MapFrom(src => (int)src.Status))

                .ReverseMap()

                    .ForCtorParam("status", opts => opts.MapFrom(src => src.StatusId))

                    .ForMember(dest => dest.PayerEmail, opts => opts.MapFrom<PayerEmailValueResolver>())

                    .ForMember(dest => dest.AdminEmail, opts => opts.MapFrom<AdminEmailValueResolver>());

        }

    }

    public class PayerEmailValueResolver : IValueResolver<EmailDbo, EmailTask, Email>

    {

        public Email Resolve(EmailDbo emailDbo, EmailTask emailTask, Email email, ResolutionContext context)

        {

            return new Email(emailDbo.SendTo, emailDbo.Subject, emailDbo.Body, emailDbo.DateSent);  

        }

    }

    public class AdminEmailValueResolver : IValueResolver<EmailDbo, EmailTask, Email>

    {

        public Email Resolve(EmailDbo emailDbo, EmailTask emailTask, Email email, ResolutionContext context)

        {

            if (String.IsNullOrWhiteSpace(emailDbo.AdminEmail) &&

                String.IsNullOrWhiteSpace(emailDbo.AdminSubject) &&

                String.IsNullOrWhiteSpace(emailDbo.AdminBody) &&

                !emailDbo.AdminDateSent.HasValue)

            {

                return null;

            }

            return new Email(emailDbo.SendTo, emailDbo.Subject, emailDbo.Body, emailDbo.DateSent);  

        }

    }

}