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

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 UniverseObjectSerializer : EngineTypeYamlSerializerBase<IUniverseObject>
{
    public override IUniverseObject? Read(IParser parser, Type type, ObjectDeserializer rootDeserializer)
    {
        bool isTrackingController = ProgressionTracker.Progression.ApproximatelyEquals(0f);

        string name;
        string id;

        IUniverseObject universeObject;
        IStateEnable stateEnable;
        IBehaviourController behaviourController;
        List<IUniverseObject> children;

        parser.Consume<MappingStart>();

        if (parser.Consume<Scalar>().Value.CompareTo(nameof(IUniverseObject.Name)) != 0)
            throw new();
        name = parser.Consume<Scalar>().Value;
        ProgressionTracker.Set(isTrackingController ? .1f : ProgressionTracker.Progression, $"Reading {name}");

        if (parser.Consume<Scalar>().Value.CompareTo(nameof(IUniverseObject.Id)) != 0)
            throw new();
        id = 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 ? .3f : ProgressionTracker.Progression, $"Creating {instanceSerializedClass.Type}");
        universeObject = (IUniverseObject)instanceSerializedClass.CreateInstance(EntityRegistry);

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

        if (parser.Consume<Scalar>().Value.CompareTo(nameof(IUniverseObject.BehaviourController)) != 0)
            throw new();
        behaviourController = (IBehaviourController)rootDeserializer(typeof(IBehaviourController))!;

        if (parser.Consume<Scalar>().Value.CompareTo(nameof(IUniverseObject.Children)) != 0)
            throw new();
        children = (List<IUniverseObject>)rootDeserializer(typeof(List<IUniverseObject>))!;

        parser.Consume<MappingEnd>();

        universeObject.Id = id;
        universeObject.Name = name;

        stateEnable.Assign(universeObject);
        universeObject.Assign(stateEnable);

        behaviourController.Assign(universeObject);
        universeObject.Assign(behaviourController);

        foreach (IUniverseObject child in children)
            universeObject.AddChild(child);

        ProgressionTracker.Set(isTrackingController ? .3f : ProgressionTracker.Progression, $"Created {name}");
        return universeObject;
    }

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

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

        emitter.Emit(new MappingStart());

        emitter.Emit(new Scalar(nameof(IUniverseObject.Name)));
        emitter.Emit(new Scalar(universeObject.Name));

        emitter.Emit(new Scalar(nameof(IUniverseObject.Id)));
        emitter.Emit(new Scalar(universeObject.Id));

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

        emitter.Emit(new Scalar(nameof(IUniverseObject.StateEnable)));
        serializer(universeObject.StateEnable);

        emitter.Emit(new Scalar(nameof(IUniverseObject.BehaviourController)));
        serializer(universeObject.BehaviourController);

        emitter.Emit(new Scalar(nameof(IUniverseObject.Children)));
        serializer(universeObject.Children.Where(c => !c.GetType().HasAttribute<IgnoreSerializationAttribute>()));

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