using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Linq;

using YamlDotNet.Serialization;

using YamlDotNet.Serialization.TypeInspectors;

using YamlDotNet.Core;

using YamlDotNet.Core.Events;

using  YamlDotNet.Serialization.ObjectGraphVisitors;

public class Program

{

    public static void Main()

    {

        var serializer = new SerializerBuilder()

            .WithTypeInspector(inner => new CommentGatheringTypeInspector(inner))

            .WithEmissionPhaseObjectGraphVisitor(args => new CommentsObjectGraphVisitor(args.InnerVisitor))

            .Build();

​

        var address = new Address

        {

            street = "123 Tornado Alley\nSuite 16",

            city = "East Westville",

            state = "KS"

        };

        var receipt = new Receipt

        {

            receipt = "Oz-Ware Purchase Invoice",

            date = new DateTime(2007, 8, 6),

            customer = new Customer

            {

                given = "Dorothy",

                family = "Gale"

            },

                items = new Item[]

            {

                new Item

                {

                    part_no = "A4786",

                    descrip = "Water Bucket (Filled)",

                    price = 1.47M,

                    quantity = 4

                },

                    new Item

                {

                    part_no = "E1628",

                    descrip = "High Heeled \"Ruby\" Slippers",

                    price = 100.27M,

                    quantity = 1

                }

            },

                bill_to = address,

            ship_to = address,

            specialDelivery = "Follow the Yellow Brick\n" +

                "Road to the Emerald City.\n" +

                "Pay no attention to the\n" +

                "man behind the curtain."

        };      

        var yaml = serializer.Serialize(receipt);

        Console.WriteLine(yaml);

        var deserializer = new DeserializerBuilder().Build();

        deserializer.Deserialize<Receipt>(yaml);

    }

}

​

public class CommentGatheringTypeInspector : TypeInspectorSkeleton

{

    private readonly ITypeInspector innerTypeDescriptor;

    public CommentGatheringTypeInspector(ITypeInspector innerTypeDescriptor)

    {

        if (innerTypeDescriptor == null)

        {

            throw new ArgumentNullException("innerTypeDescriptor");

        }

        this.innerTypeDescriptor = innerTypeDescriptor;

    }

    public override IEnumerable<IPropertyDescriptor> GetProperties(Type type, object container)

    {

        return innerTypeDescriptor

            .GetProperties(type, container)

            .Select(d => new CommentsPropertyDescriptor(d));

    }

    private sealed class CommentsPropertyDescriptor : IPropertyDescriptor

    {

        private readonly IPropertyDescriptor baseDescriptor;

        public CommentsPropertyDescriptor(IPropertyDescriptor baseDescriptor)

        {

            this.baseDescriptor = baseDescriptor;

            Name = baseDescriptor.Name;

        }

        public string Name { get; set; }

        public Type Type { get { return baseDescriptor.Type; } }

        public Type TypeOverride

        {

            get { return baseDescriptor.TypeOverride; }

            set { baseDescriptor.TypeOverride = value; }

        }

        public int Order { get; set; }

        public ScalarStyle ScalarStyle

        {

            get { return baseDescriptor.ScalarStyle; }

            set { baseDescriptor.ScalarStyle = value; }

        }

        public bool CanWrite { get { return baseDescriptor.CanWrite; } }

        public void Write(object target, object value)

        {

            baseDescriptor.Write(target, value);

        }

        public T GetCustomAttribute<T>() where T : Attribute

        {

            return baseDescriptor.GetCustomAttribute<T>();

        }

        public IObjectDescriptor Read(object target)

        {

            var description = baseDescriptor.GetCustomAttribute<DescriptionAttribute>();

            return description != null

                ? new CommentsObjectDescriptor(baseDescriptor.Read(target), description.Description)

                : baseDescriptor.Read(target);

        }

    }

}

​

public sealed class CommentsObjectDescriptor : IObjectDescriptor

{

    private readonly IObjectDescriptor innerDescriptor;

    public CommentsObjectDescriptor(IObjectDescriptor innerDescriptor, string comment)

    {

        this.innerDescriptor = innerDescriptor;

        this.Comment = comment;

    }

    public string Comment { get; private set; }

    public object Value { get { return innerDescriptor.Value; } }

    public Type Type { get { return innerDescriptor.Type; } }

    public Type StaticType { get { return innerDescriptor.StaticType; } }

    public ScalarStyle ScalarStyle { get { return innerDescriptor.ScalarStyle; } }

}

​

public class CommentsObjectGraphVisitor : ChainedObjectGraphVisitor

{

    public CommentsObjectGraphVisitor(IObjectGraphVisitor<IEmitter> nextVisitor)

        : base(nextVisitor)

    {

    }   

    public override bool EnterMapping(IPropertyDescriptor key, IObjectDescriptor value, IEmitter context)

    {

        var commentsDescriptor = value as CommentsObjectDescriptor;

        if (commentsDescriptor != null && commentsDescriptor.Comment != null)

        {

            context.Emit(new Comment(commentsDescriptor.Comment, false));

        }

        return base.EnterMapping(key, value, context);

    }

}

​

public class Address {

    public string street { get; set; }

    public string city   { get; set; }

    public string state  { get; set; }

}

​

public class Receipt {

    public string   receipt         { get; set; }

    public DateTime date            { get; set; }

    public Customer customer        { get; set; }

    public Item[]   items           { get; set; }

    [Description("The address for the invoice")]

    public Address  bill_to         { get; set; }

​

    [Description("The address where the goods are to be delivered")]

    public Address  ship_to         { get; set; }

    [Description("Please follow these instructions carefully!")]

    public string   specialDelivery { get; set; }

}

​

public class Customer {

    public string given  { get; set; }

    public string family { get; set; }

}

​

public class Item {

    public string  part_no  { get; set; }

    public string  descrip  { get; set; }

    [Description("Unit price in USD")]

    public decimal price    { get; set; }

    public int     quantity { get; set; }

}

​