// =============================================
//  Aster: asset_loader.h
//  Copyright (c) 2020-2024 Anish Bhobe
// =============================================

#pragma once

#include "aster/aster.h"

#include "aster/core/buffer.h"
#include "render_resource_manager.h"

#include "ecs_adapter.h"

namespace tinygltf
{
class Model;
struct Image;
} // namespace tinygltf

struct Image;
struct Texture;

constexpr auto GLTF_ASCII_FILE_EXTENSION = ".gltf";
constexpr auto GLTF_BINARY_FILE_EXTENSION = ".glb";

struct Material
{
    vec4 m_AlbedoFactor;           // 16   16
    vec3 m_EmissionFactor;         // 12   28
    f32 m_MetalFactor;             // 04   32
    f32 m_RoughFactor;             // 04   36
    TextureHandle m_AlbedoTex;     // 04   40
    TextureHandle m_NormalTex;     // 04   44
    TextureHandle m_MetalRoughTex; // 04   48
    TextureHandle m_OcclusionTex;  // 04   52
    TextureHandle m_EmissionTex;   // 04   56
    f32 m_AlphaBlend;              /* 04   60
 AlphaBlend < 0 means Opaque
 AlphaBlend > 1 means Blend
 AlphaBlend in [0,1] means cutoff */
};

// If this is changed, ensure the shaders are changed accordingly.
static_assert(sizeof(Material) == 60);

struct VertexData
{
    vec4 m_Normal;
    vec2 m_TexCoord0 = vec2{0.0f, 0.0f};
    vec2 m_TexCoord1 = vec2{0.0f, 0.0f};
    vec4 m_Color0 = vec4{1.0f, 1.0f, 1.0f, 1.0f};
};

struct Model
{
    eastl::vector<TextureHandle> m_Textures;
    eastl::vector<Entity> m_Entities;

    IndexHandle m_IndexHandle;
    GeometryHandle m_VertexPositionHandle;
    GeometryHandle m_VertexDataHandle;
    MaterialHandle m_MaterialHandle;
    Entity m_RootEntity;

    void Destroy(RenderResourceManager *resourceManager, EcsRegistry *registry);
};

struct CModel
{
};

struct AssetLoader
{
    RenderResourceManager *m_ResourceManager;
    entt::registry *m_Registry;

    vk::CommandPool m_CommandPool;
    vk::CommandBuffer m_CommandBuffer;
    vk::Queue m_TransferQueue;
    u32 m_TransferQueueIndex;
    u32 m_GraphicsQueueIndex;

    void LoadHdrImage(Texture *texture, cstr path, cstr name = nullptr) const;
    Model LoadModelToGpu(cstr path, cstr name = nullptr);

    constexpr static auto ANormal = "NORMAL";
    constexpr static auto APosition = "POSITION";
    constexpr static auto ATangent = "TANGENT";
    constexpr static auto ATexCoord0 = "TEXCOORD_0";
    constexpr static auto ATexCoord1 = "TEXCOORD_1";
    constexpr static auto AColor0 = "COLOR_0";
    constexpr static auto AJoints0 = "JOINTS_0";
    constexpr static auto AWeights0 = "WEIGHTS_0";

    AssetLoader(RenderResourceManager *resourceManager, EcsRegistry *registry, vk::Queue transferQueue,
                u32 transferQueueIndex, u32 graphicsQueueIndex);
    ~AssetLoader();

    AssetLoader(AssetLoader &&other) noexcept;
    AssetLoader &operator=(AssetLoader &&other) noexcept;

  private:
    TextureHandle LoadImageToGpu(StagingBuffer *stagingBuffer, tinygltf::Image *image, bool isSrgb) const;
    void
    ProcessNode(tinygltf::Model *model, eastl::vector<vec4> *vertexPositions, eastl::vector<VertexData> *vertexData,
                eastl::vector<u32> *indices, eastl::vector<Entity> *entities,
                const std::function<u32(i32)> &loadMaterial, int current, Entity parent);

  public:
    DISALLOW_COPY_AND_ASSIGN(AssetLoader);
};

void GenerateMipMaps(vk::CommandBuffer commandBuffer, Texture *texture, vk::ImageLayout initialLayout,
                     vk::ImageLayout finalLayout,
                     vk::PipelineStageFlags2 prevStage = vk::PipelineStageFlagBits2::eAllCommands,
                     vk::PipelineStageFlags2 finalStage = vk::PipelineStageFlagBits2::eAllCommands);