#pragma once

#include "Rendering/Host/HostFwd.h"
#include "Rendering/Viewport/ViewportContentRenderer.h"
#include "ViewportRenderTargets.h"

#include <XCEngine/Rendering/RenderContext.h>
#include <XCEngine/UI/Types.h>

#include <cstdint>
#include <string>
#include <string_view>
#include <unordered_map>
#include <vector>

namespace XCEngine::UI::Editor::App {

class ViewportHostService {
public:
    ViewportHostService();
    ~ViewportHostService();

    void AttachWindowRenderer(Rendering::Host::ViewportRenderHost& windowRenderer);
    void DetachWindowRenderer();
    void SetSurfacePresentationEnabled(bool enabled);
    void SetContentRenderer(
        std::string_view viewportId,
        IViewportContentRenderer* renderer,
        const ViewportResourceRequirements& requirements = {});

    void Shutdown();
    void BeginFrame();

    ViewportFrame RequestViewport(
        std::string_view viewportId,
        const ::XCEngine::UI::UISize& requestedSize);

    void RenderRequestedViewports(
        const ::XCEngine::Rendering::RenderContext& renderContext);

private:
    struct ViewportEntry {
        IViewportContentRenderer* renderer = nullptr;
        ViewportResourceRequirements requirements = {};
        std::uint32_t requestedWidth = 0;
        std::uint32_t requestedHeight = 0;
        bool requestedThisFrame = false;
        bool renderedThisFrame = false;
        ViewportRenderTargets renderTargets = {};
        std::string statusText = {};
    };

    void ReleaseWindowResources();
    ViewportEntry& GetOrCreateEntry(std::string_view viewportId);
    void DestroyViewportEntry(ViewportEntry& entry);
    void DestroyRetiredTargets();
    void ReclaimRetiredTargetsForCurrentSlot();
    void RetireViewportTargets(ViewportRenderTargets& targets);
    bool EnsureViewportResources(ViewportEntry& entry);
    void ApplyViewportFallback(
        ViewportEntry& entry,
        const ::XCEngine::Rendering::RenderContext& renderContext,
        const ViewportRenderResult& renderResult);
    void ClearViewport(
        ViewportEntry& entry,
        const ::XCEngine::Rendering::RenderContext& renderContext,
        float r,
        float g,
        float b,
        float a);
    ViewportFrame BuildFrame(
        const ViewportEntry& entry,
        const ::XCEngine::UI::UISize& requestedSize) const;

    Rendering::Host::ViewportRenderHost* m_windowRenderer = nullptr;
    ::XCEngine::RHI::RHIDevice* m_device = nullptr;
    ViewportRenderTargetManager m_renderTargetManager = {};
    bool m_surfacePresentationEnabled = false;
    std::unordered_map<std::string, ViewportEntry> m_entries = {};
    std::vector<std::vector<ViewportRenderTargets>> m_retiredTargetsBySlot = {};
};

} // namespace XCEngine::UI::Editor::App