using System;

using Engine.Core;

using YamlDotNet.Core;
using YamlDotNet.Core.Events;
using YamlDotNet.Serialization;

namespace Engine.Serializers.Yaml;

public class Ray2DConverter : EngineTypeYamlSerializerBase<Ray2D>
{
    public override Ray2D Read(IParser parser, Type type, ObjectDeserializer rootDeserializer)
    {
        parser.Consume<MappingStart>();

        if (parser.Consume<Scalar>().Value.CompareTo(nameof(Ray2D.Origin)) != 0)
            throw new ArgumentException($"{nameof(Ray2D)} mapping must start with {nameof(Ray2D.Origin)}");
        Vector2D origin = (Vector2D)rootDeserializer(typeof(Vector2D))!;

        if (parser.Consume<Scalar>().Value.CompareTo(nameof(Ray2D.Direction)) != 0)
            throw new ArgumentException($"{nameof(Ray2D)} mapping must end with {nameof(Ray2D.Direction)}");
        Vector2D direction = (Vector2D)rootDeserializer(typeof(Vector2D))!;

        parser.Consume<MappingEnd>();

        return new Ray2D(origin, direction);
    }

    public override void WriteYaml(IEmitter emitter, object? value, Type type, ObjectSerializer serializer)
    {
        Ray2D ray2D = (Ray2D)value!;

        emitter.Emit(new MappingStart());
        emitter.Emit(new Scalar(nameof(ray2D.Origin)));
        serializer(ray2D.Origin, typeof(Vector2D));
        emitter.Emit(new Scalar(nameof(ray2D.Direction)));
        serializer(ray2D.Direction, typeof(Vector2D));
        emitter.Emit(new MappingEnd());
    }
}