using System;

using Syntriax.Engine.Core;
using Syntriax.Engine.Core.Serialization;

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

namespace Syntriax.Engine.Serializers.Yaml;

public class BehaviourConverter : EngineTypeYamlSerializerBase<IBehaviour>
{
    public override IBehaviour? Read(IParser parser, Type type, ObjectDeserializer rootDeserializer)
    {
        bool isTrackingController = ProgressionTracker.Progression.ApproximatelyEquals(0f);
        ProgressionTracker.Set(isTrackingController ? .25f : ProgressionTracker.Progression, $"Reading behaviour information");

        string id;
        int priority;

        IBehaviour behaviour;
        IStateEnable stateEnable;

        parser.Consume<MappingStart>();

        if (parser.Consume<Scalar>().Value.CompareTo(nameof(IBehaviour.Id)) != 0)
            throw new();
        id = parser.Consume<Scalar>().Value;

        if (parser.Consume<Scalar>().Value.CompareTo(nameof(IBehaviour.Priority)) != 0)
            throw new();
        priority = int.Parse(parser.Consume<Scalar>().Value);

        if (parser.Consume<Scalar>().Value.CompareTo(SERIALIZED_SCALAR_NAME) != 0)
            throw new();
        SerializedClass instanceSerializedClass = (SerializedClass)rootDeserializer(typeof(SerializedClass))!;
        ProgressionTracker.Set(isTrackingController ? .5f : ProgressionTracker.Progression, $"Creating {instanceSerializedClass.Type}");
        behaviour = (IBehaviour)instanceSerializedClass.CreateInstance(EntityRegistry);

        if (parser.Consume<Scalar>().Value.CompareTo(nameof(IBehaviour.StateEnable)) != 0)
            throw new();
        stateEnable = (IStateEnable)rootDeserializer(typeof(IStateEnable))!;

        parser.Consume<MappingEnd>();

        behaviour.Id = id;
        behaviour.Priority = priority;

        stateEnable.Assign(behaviour);
        behaviour.Assign(stateEnable);

        ProgressionTracker.Set(isTrackingController ? 1f : ProgressionTracker.Progression, $"Created {instanceSerializedClass.Type}");
        return behaviour;
    }

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

        bool isTrackingController = ProgressionTracker.Progression.ApproximatelyEquals(0f);
        ProgressionTracker.Set(isTrackingController ? .25f : ProgressionTracker.Progression, $"Serializing behaviour");

        emitter.Emit(new MappingStart());

        emitter.Emit(new Scalar(nameof(IBehaviour.Id)));
        emitter.Emit(new Scalar(behaviour.Id));

        emitter.Emit(new Scalar(nameof(IBehaviour.Priority)));
        emitter.Emit(new Scalar(behaviour.Priority.ToString()));

        emitter.Emit(new Scalar(SERIALIZED_SCALAR_NAME));
        serializer(new SerializedClass(behaviour));

        emitter.Emit(new Scalar(nameof(IBehaviour.StateEnable)));
        serializer(behaviour.StateEnable);

        ProgressionTracker.Set(isTrackingController ? 1f : ProgressionTracker.Progression, $"Serialized behaviour");
        emitter.Emit(new MappingEnd());
    }
}