using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;

using YamlDotNet.Serialization;
using YamlDotNet.Serialization.NamingConventions;

namespace Syntriax.Engine.Core.Serialization;

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

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

        return serializerBuilder.Build();
    }

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

        foreach (IEngineTypeYamlSerializer typeConverter in GetEngineYamlTypeConverters())
        {
            typeConverter.EntityRegistry = entityRegistry;
            serializerBuilder = serializerBuilder.WithTypeConverter(typeConverter);
        }

        return serializerBuilder.Build();
    }

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

    public static string Serialize(object instance)
    {
        return serializer.Serialize(instance);
    }

    public static object Deserialize(string yaml)
    {
        EntityRegistry entityRegistry = new();
        object result = GetDeserializer(entityRegistry).Deserialize(yaml)!;
        entityRegistry.AssignAll();
        return result;
    }

    public static object Deserialize(string yaml, Type type)
    {
        EntityRegistry entityRegistry = new();
        object result = GetDeserializer(entityRegistry).Deserialize(yaml, type)!;
        entityRegistry.AssignAll();
        return result;
    }

    public static T Deserialize<T>(string yaml)
    {
        EntityRegistry entityRegistry = new();
        T result = GetDeserializer(entityRegistry).Deserialize<T>(yaml);
        entityRegistry.AssignAll();
        return result;
    }
}