using System.Reflection;
using YamlDotNet.Serialization;
using YamlDotNet.Serialization.NamingConventions;

namespace Syntriax.Engine.Serialization;

public static class Serializer
{
    private static readonly ISerializer serializer = GetSerializer();
    private static ISerializer GetSerializer(EntityFinder? entityFinder = null)
    {
        SerializerBuilder serializerBuilder = new SerializerBuilder()
                .WithNamingConvention(PascalCaseNamingConvention.Instance)
                .DisableAliases();

        foreach (IEngineTypeYamlConverter typeConverter in GetEngineYamlTypeConverters())
            serializerBuilder = serializerBuilder.WithTypeConverter(typeConverter);

        if (entityFinder is not null)
            serializerBuilder = serializerBuilder.WithTypeConverter(new EntityConverter(entityFinder.Entities));

        return serializerBuilder.Build();
    }

    private static readonly IDeserializer deserializer = GetDeserializer();
    private static IDeserializer GetDeserializer()
    {
        DeserializerBuilder serializerBuilder = new DeserializerBuilder()
                .WithNamingConvention(PascalCaseNamingConvention.Instance);

        foreach (IEngineTypeYamlConverter typeConverter in GetEngineYamlTypeConverters())
            serializerBuilder = serializerBuilder.WithTypeConverter(typeConverter);

        return serializerBuilder.Build();
    }

    private static IEnumerable<IEngineTypeYamlConverter> GetEngineYamlTypeConverters()
    {
        foreach (Type type in Assembly.GetExecutingAssembly().GetTypes().Where(t => typeof(IEngineTypeYamlConverter).IsAssignableFrom(t) && t.IsClass && !t.IsAbstract))
            yield return (Activator.CreateInstance(type) as IEngineTypeYamlConverter)!;
    }

    public static string Serialize(object instance)
    {
        EntityFinder entityFinder = new();
        entityFinder.FindEntitiesUnder(instance);
        ISerializer serializer = GetSerializer(entityFinder);
        return serializer.Serialize(entityFinder.Entities);
    }

    public static object Deserialize(string yaml)
    {
        return deserializer.Deserialize(yaml)!;
    }

    public static T Deserialize<T>(string yaml)
    {
        return deserializer.Deserialize<T>(yaml);
    }
}