using System;

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

namespace Syntriax.Engine.Core.Serialization;

public class TriangleSerializer : IEngineTypeYamlSerializer
{
    public bool Accepts(Type type) => type == typeof(Triangle);

    public object? ReadYaml(IParser parser, Type type, ObjectDeserializer rootDeserializer)
    {
        parser.Consume<MappingStart>();

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

        if (parser.Consume<Scalar>().Value.CompareTo(nameof(Triangle.B)) != 0)
            throw new ArgumentException($"{nameof(Triangle)} mapping must have {nameof(Triangle.B)} after {nameof(Triangle.A)}");
        Vector2D b = (Vector2D)rootDeserializer(typeof(Vector2D))!;

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

        parser.Consume<MappingEnd>();

        return new Triangle(a, b, c);
    }

    public void WriteYaml(IEmitter emitter, object? value, Type type, ObjectSerializer serializer)
    {
        Triangle aabb = (Triangle)value!;

        emitter.Emit(new MappingStart());
        emitter.Emit(new Scalar(nameof(Triangle.A)));
        serializer(aabb.A, typeof(Vector2D));
        emitter.Emit(new Scalar(nameof(Triangle.B)));
        serializer(aabb.B, typeof(Vector2D));
        emitter.Emit(new Scalar(nameof(Triangle.C)));
        serializer(aabb.C, typeof(Vector2D));
        emitter.Emit(new MappingEnd());
    }
}