using System;
using System.Collections.Generic;
using Engine.Serialization.DTOs;

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

namespace Engine.Serialization;

public class GameObjectDTOListConverter : IYamlTypeConverter
{
    public bool Accepts(Type type)
    {
        return type == typeof(List<GameObjectDTO>);
    }

    public object ReadYaml(IParser parser, Type type)
    {
        var gameObjects = new List<GameObjectDTO>();
        if (parser.Current is SequenceStart)
        {
            parser.MoveNext();
            while (parser.Current != null && !(parser.Current is SequenceEnd))
            {
                gameObjects.Add((GameObjectDTO)new GameObjectYamlConverter().ReadYaml(parser, typeof(GameObjectDTO)));
                parser.MoveNext();
            }
        }
        return gameObjects;
    }

    public void WriteYaml(IEmitter emitter, object? value, Type type)
    {
        var gameObjects = (List<GameObjectDTO>)(value ?? throw new Exception());
        emitter.Emit(new SequenceStart(null, null, false, SequenceStyle.Block));
        foreach (var gameObject in gameObjects)
            new GameObjectYamlConverter().WriteYaml(emitter, gameObject, typeof(BehaviourDTO));
        emitter.Emit(new SequenceEnd());
    }
}