/**
 * @file graphics_context.h
 * @author Piotr Krygier (everyonecancode@gmail.com)
 * @brief Graphics context for Red Scarf Engine
 * @version 0.1
 * @date 2024-05-22
 *
 * @copyright Copyright (c) 2024
 *
*/

#ifndef GRAPHICS_CONTEXT_H
#define GRAPHICS_CONTEXT_H

#include "vulkan/vulkan_core.h"
#include "vulkan_commons.h"
#include "utilities/linked_list.h"

#include <stdint.h>
#include <stdbool.h>
#include <vulkan/vulkan.h>
#include <vk_mem_alloc.h>
#include <GLFW/glfw3.h>

#define MAX_MESH_NUMBER 256
#define MAX_INSTANCE_NUMBER 256

/**
 * @brief Maximum number of textures that can be loaded
 *
 */
#define RSE_MAX_IMAGE_COUNT 256

#define MAX_DESCRIPTOR_SETS 16
#define MAX_PIPELINE_COUNT 16
#define MAX_DESCRIPTOR_POOLS_COUNT (16)

RSE_LINKED_LIST_DEFINE(shader_module_list_t, VkShaderModule);

/**
 * @brief Represents data within vertex or instance buffer.
 *
 */
struct buffer_data_t
{
    size_t count;
    size_t buffer_offset;
};

/**
 * @brief Wrapper for Vulkan buffer. Holds allocation data;
 *
 */
struct vulkan_image_t
{
    uint8_t id_taken;
    size_t allocated_size;
    VkImage image;
    VkImageView image_view;
    VmaAllocation allocation;
    VmaAllocationInfo allocation_info;
};

/**
 * @brief Represents instance of a mesh and shows where it's located in instance buffer
 *
 */
struct internal_instance_data_t
{
    uint8_t instance_taken;
    uint8_t instance_buffer_offset;
};

/**
 * @brief Mesh data, with unique id and dynamic arrays holding vertices and indices.
 * One mesh can have multiple instances.
 *
 */
struct mesh_t
{
    uint8_t is_mesh_id_taken;
    uint32_t unique_id;
    uint8_t instance_count;
    struct buffer_data_t vertex_data;
    struct buffer_data_t index_data;
    struct internal_instance_data_t instance_data[MAX_INSTANCE_NUMBER];
};

struct pipeline_internal_t
{
    size_t pipelines_count;
    size_t descriptor_set_layouts_count;
    VkPipeline pipelines[MAX_PIPELINE_COUNT];
    VkPipelineLayout pipeline_layout;
};

struct graphics_context_t
{
    GLFWwindow* window_handle;
    VkDevice device;
    VkSurfaceKHR surface;
    VkInstance instance;
    VkQueue graphics_queue;
    VmaAllocator allocator;
    VkSampler sampler;
    VkPhysicalDevice physical_device;
    VkCommandPool command_pool;
    VkCommandBuffer command_buffers[SWAP_BUFFER_COUNT];
    VkDescriptorSet descriptor_sets[SWAP_BUFFER_COUNT];
    VkDescriptorSet descriptor_sets_bindless;
    VkImageView* swapchain_image_views;
    VkExtent2D swapchain_extent;
    VkRenderPass render_pass;
    VkFramebuffer* swapchain_framebuffers;
    VkSwapchainKHR swapchain;
    uint32_t swapchain_images_count;
    VkImage* swapchain_images;
    VkQueue present_queue;
    VkSemaphore image_available_semaphores[SWAP_BUFFER_COUNT];
    VkSemaphore render_finished_semaphores[SWAP_BUFFER_COUNT];
    VkFence in_flight_fences[SWAP_BUFFER_COUNT];
    VkDescriptorPool descriptor_pool;
    VkDescriptorPool descriptor_pool_bindless;
    struct pipeline_internal_t pipelines_data;
#ifndef NDEBUG
    VkDebugUtilsMessengerEXT debug_messenger;
#endif // !NDEBUG
    bool is_framebuffer_resized; //TODO: Consider moving this to heap
    uint32_t current_frame;
    uint32_t queue_family_indices[1];
    struct vulkan_buffer_t uniform_buffers[SWAP_BUFFER_COUNT];
    /* GPU visible buffer */
    size_t vertex_offset;
    struct vulkan_buffer_t vertex_buffer;
    struct vulkan_buffer_t index_buffer;
    struct vulkan_buffer_t instance_buffers[MAX_MESH_NUMBER];
    struct vulkan_buffer_t draw_indirect_command_buffer;
    struct vulkan_image_t texture_images[RSE_MAX_IMAGE_COUNT];
    struct vulkan_image_t depth_image;
    struct vulkan_image_t color_image;
    struct shader_module_list_t* shader_modules;
    struct mesh_t meshes[MAX_MESH_NUMBER];
};

#endif /* GRAPHICS_CONTEXT_H */