using System;
using XCEngine;
using XCEngine.Rendering;

namespace XCEngine.Rendering.Universal
{
    public abstract class ScriptableRendererData : Object
    {
        private ScriptableRendererFeature[] m_rendererFeatures;
        private ScriptableRenderer m_rendererInstance;
        private bool m_rendererInvalidated;

        protected ScriptableRendererData()
        {
        }

        internal ScriptableRenderer CreateRendererInstance()
        {
            return GetRendererInstance();
        }

        internal ScriptableRenderer GetRendererInstance()
        {
            if (m_rendererInstance == null)
            {
                m_rendererInstance = CreateRenderer();
                if (m_rendererInstance != null)
                {
                    SetupRendererInstance(m_rendererInstance);
                    m_rendererInvalidated = false;
                }
            }

            return m_rendererInstance;
        }

        internal ScriptableRendererFeature[] CreateRendererFeaturesInstance()
        {
            return GetRendererFeatures();
        }

        internal void SetupRendererInstance(
            ScriptableRenderer renderer)
        {
            if (renderer == null)
            {
                return;
            }

            SetupRenderer(renderer);
        }

        internal void SetDirtyInstance()
        {
            SetDirty();
        }

        internal string GetPipelineRendererAssetKeyInstance()
        {
            return GetPipelineRendererAssetKey();
        }

        internal void ReleaseRuntimeResourcesInstance()
        {
            ReleaseRendererSetupCache();
            ReleaseRuntimeResources();
            m_rendererInvalidated = false;
        }

        internal void ConfigureCameraRenderRequestInstance(
            CameraRenderRequestContext context)
        {
            ConfigureCameraRenderRequest(context);

            ScriptableRendererFeature[] rendererFeatures =
                GetRendererFeatures();
            for (int i = 0; i < rendererFeatures.Length; ++i)
            {
                ScriptableRendererFeature rendererFeature =
                    rendererFeatures[i];
                if (rendererFeature == null ||
                    !rendererFeature.isActive)
                {
                    continue;
                }

                rendererFeature.ConfigureCameraRenderRequest(
                    context);
            }
        }

        internal void ConfigureCameraFramePlanInstance(
            ScriptableRenderPipelinePlanningContext context)
        {
            ConfigureCameraFramePlan(context);

            ScriptableRendererFeature[] rendererFeatures =
                GetRendererFeatures();
            for (int i = 0; i < rendererFeatures.Length; ++i)
            {
                ScriptableRendererFeature rendererFeature =
                    rendererFeatures[i];
                if (rendererFeature == null ||
                    !rendererFeature.isActive)
                {
                    continue;
                }

                rendererFeature.ConfigureCameraFramePlan(
                    context);
            }
        }

        protected virtual ScriptableRenderer CreateRenderer()
        {
            return null;
        }

        protected virtual void SetupRenderer(
            ScriptableRenderer renderer)
        {
            AddRendererFeatures(
                renderer,
                GetRendererFeatures());
        }

        protected virtual void ConfigureCameraRenderRequest(
            CameraRenderRequestContext context)
        {
        }

        protected virtual void ConfigureCameraFramePlan(
            ScriptableRenderPipelinePlanningContext context)
        {
        }

        protected virtual string GetPipelineRendererAssetKey()
        {
            return string.Empty;
        }

        protected virtual ScriptableRendererFeature[] CreateRendererFeatures()
        {
            return Array.Empty<ScriptableRendererFeature>();
        }

        protected virtual void ReleaseRuntimeResources()
        {
        }

        protected bool isInvalidated
        {
            get
            {
                return m_rendererInvalidated;
            }
        }

        protected bool HasDirectionalShadow(
            CameraRenderRequestContext context)
        {
            return context != null &&
                   InternalCalls
                       .Rendering_CameraRenderRequestContext_GetHasDirectionalShadow(
                           context.nativeHandle);
        }

        protected void ClearDirectionalShadow(
            CameraRenderRequestContext context)
        {
            if (context == null)
            {
                return;
            }

            InternalCalls
                .Rendering_CameraRenderRequestContext_ClearDirectionalShadow(
                    context.nativeHandle);
        }

        protected void SetDirty()
        {
            ReleaseRendererSetupCache();
            m_rendererInvalidated = true;
        }

        protected void AddRendererFeature(
            ScriptableRenderer renderer,
            ScriptableRendererFeature rendererFeature)
        {
            if (renderer == null ||
                rendererFeature == null)
            {
                return;
            }

            renderer.AddFeatureInstance(rendererFeature);
        }

        protected void AddRendererFeatures(
            ScriptableRenderer renderer,
            ScriptableRendererFeature[] rendererFeatures)
        {
            if (renderer == null ||
                rendererFeatures == null)
            {
                return;
            }

            for (int i = 0; i < rendererFeatures.Length; ++i)
            {
                AddRendererFeature(
                    renderer,
                    rendererFeatures[i]);
            }
        }

        private ScriptableRendererFeature[] GetRendererFeatures()
        {
            if (m_rendererFeatures == null)
            {
                m_rendererFeatures =
                    CreateRendererFeatures() ??
                    Array.Empty<ScriptableRendererFeature>();
            }

            return m_rendererFeatures;
        }

        private void ReleaseRendererSetupCache()
        {
            if (m_rendererInstance != null)
            {
                m_rendererInstance.ReleaseRuntimeResourcesInstance();
                m_rendererInstance = null;
                m_rendererFeatures = null;
                return;
            }

            if (m_rendererFeatures == null)
            {
                return;
            }

            for (int i = 0; i < m_rendererFeatures.Length; ++i)
            {
                ScriptableRendererFeature rendererFeature =
                    m_rendererFeatures[i];
                if (rendererFeature != null)
                {
                    rendererFeature.ReleaseRuntimeResourcesInstance();
                }
            }

            m_rendererFeatures = null;
        }
    }
}