using XCEngine;
using XCEngine.Rendering;

namespace XCEngine.Rendering.Universal
{
    public sealed class UniversalRenderer : ScriptableRenderer
    {
        private readonly UniversalRendererData m_rendererData;
        private readonly UniversalShadowCasterBlock m_shadowCasterBlock =
            new UniversalShadowCasterBlock();
        private readonly UniversalDepthPrepassBlock m_depthPrepassBlock =
            new UniversalDepthPrepassBlock();
        private readonly UniversalMainSceneBlock m_mainSceneBlock =
            new UniversalMainSceneBlock();
        private readonly UniversalPostProcessBlock m_postProcessBlock =
            new UniversalPostProcessBlock();
        private readonly UniversalFinalOutputBlock m_finalOutputBlock =
            new UniversalFinalOutputBlock();

        public UniversalRenderer(
            UniversalRendererData rendererData)
        {
            m_rendererData =
                rendererData ??
                ScriptableObject
                    .CreateInstance<UniversalRendererData>() ??
                new UniversalRendererData();
        }

        protected override void ConfigureCameraFramePlan(
            ScriptableRenderPipelinePlanningContext context)
        {
            if (context == null)
            {
                return;
            }

            m_shadowCasterBlock.ConfigureCameraFramePlan(
                context,
                m_rendererData.GetShadowCasterBlockInstance());
            m_depthPrepassBlock.ConfigureCameraFramePlan(
                context,
                m_rendererData.GetDepthPrepassBlockInstance());
        }

        protected override void FinalizeCameraFramePlan(
            ScriptableRenderPipelinePlanningContext context)
        {
            if (context == null)
            {
                return;
            }

            base.FinalizeCameraFramePlan(context);
            m_finalOutputBlock.FinalizeCameraFramePlan(
                context,
                m_postProcessBlock);
        }

        protected override void ConfigureRenderSceneSetup(
            RenderSceneSetupContext context)
        {
            if (context == null)
            {
                return;
            }

            m_mainSceneBlock.ConfigureRenderSceneSetup(
                context);
        }

        protected override void ConfigureDirectionalShadowExecutionState(
            DirectionalShadowExecutionContext context)
        {
            if (context == null)
            {
                return;
            }

            m_shadowCasterBlock
                .ConfigureDirectionalShadowExecutionState(
                    context,
                    m_rendererData.GetShadowCasterBlockInstance());
        }

        protected override void AddRenderPasses(
            RenderingData renderingData)
        {
            if (renderingData == null)
            {
                return;
            }

            switch (renderingData.stage)
            {
                case CameraFrameStage.ShadowCaster:
                    m_shadowCasterBlock.EnqueueRenderPasses(
                        this,
                        m_rendererData.GetShadowCasterBlockInstance());
                    break;
                case CameraFrameStage.DepthOnly:
                    m_depthPrepassBlock.EnqueueRenderPasses(
                        this,
                        m_rendererData.GetDepthPrepassBlockInstance());
                    break;
                case CameraFrameStage.MainScene:
                    m_mainSceneBlock.EnqueueRenderPasses(
                        this,
                        m_rendererData.GetMainSceneInstance());
                    break;
                case CameraFrameStage.PostProcess:
                    m_postProcessBlock.EnqueueRenderPasses(
                        this,
                        renderingData);
                    break;
                case CameraFrameStage.FinalOutput:
                    m_finalOutputBlock.EnqueueRenderPasses(
                        this,
                        renderingData);
                    break;
            }
        }
    }
}