#include "HydraShadowBufferManager.h"
#include "../scheduler/HydraTaskScheduler.h"
#include "../task/buffer/HydraCreateGPUBufferTask.hpp"
#include "../task/buffer/HydraUpdateWholeGPUBufferTask.hpp"
#include "../task/buffer/HydraUpdatePartialGPUBufferTask.hpp"
#include "../task/buffer/HydraCreateUnBoundTextureTask.hpp"
#include "../task/renderer/HydraCreateCascadeShadowFrameBuffer.hpp"
#include "../task/renderer/HydraCreateShadowFrameBuffer.hpp"

void HydraShadowBufferManager::Initialise()
{
    HydraTaskScheduler *task_scheduler = GetEngine()->TaskScheduler();
    for(uint32_t i = 0; i < MAX_DIRECTIONAL_SHADOWS; i++)
    {
        m_available_dir.push(i);
    }
    for(uint32_t i = 0; i < MAX_SPOT_SHADOWS; i++)
    {
        m_available_spot.push(i);
    }
    m_directional_shadow_buffer.resize(MAX_DIRECTIONAL_SHADOWS);
    m_spot_shadow_buffer.resize(MAX_SPOT_SHADOWS);


    uint32_t buffer_size = (MAX_DIRECTIONAL_SHADOWS * sizeof(HydraDirectionalShadowSourceComponent));
                          
    HydraID create_gpu_buffer_task_id = task_scheduler->CreateTask<HydraCreateGPUBufferTask>(HydraThreadAffinity::Render);
    HydraCreateGPUBufferTask *task = static_cast<HydraCreateGPUBufferTask *>(task_scheduler->GetTask(create_gpu_buffer_task_id));
    task->Intialise("DirectionalShadowBuffer", 1, buffer_size, &m_directional_shadow_buffer_id, HYDRA_BUFFER_TYPE::HYDRA_SSBO_BUFFER);
    task_scheduler->WaitForTask(create_gpu_buffer_task_id);

    buffer_size = (MAX_SPOT_SHADOWS * sizeof(HydraSpotShadowSourceComponent));

    create_gpu_buffer_task_id = task_scheduler->CreateTask<HydraCreateGPUBufferTask>(HydraThreadAffinity::Render);
    HydraCreateGPUBufferTask *spot_task = static_cast<HydraCreateGPUBufferTask *>(task_scheduler->GetTask(create_gpu_buffer_task_id));
    spot_task->Intialise("SpotShadowBuffer", 1, buffer_size, &m_spot_shadow_buffer_id, HYDRA_BUFFER_TYPE::HYDRA_SSBO_BUFFER);
    task_scheduler->WaitForTask(create_gpu_buffer_task_id);
}
void HydraShadowBufferManager::Shutdown()
{

}
HydraID HydraShadowBufferManager::AddDirectionalShadow(HydraDirectionalShadowSourceComponent shadow)
{
    std::lock_guard<std::mutex> lock(m_mutex);
    if(m_available_dir.size() == 0)
    {
        return INVALID_HYDRA_ID;
    }

    HydraID shadow_id = m_available_dir.front();
    shadow.shadow_id = shadow_id;
    m_directional_shadow_buffer[shadow_id] = shadow;
    return shadow_id;
}
HydraID HydraShadowBufferManager::AddSpotShadow(HydraSpotShadowSourceComponent shadow)
{
    std::lock_guard<std::mutex> lock(m_mutex);
    if(m_available_spot.size() == 0)
    {
        return INVALID_HYDRA_ID;
    }

    HydraID shadow_id = m_available_spot.front();
    m_spot_shadow_buffer[shadow_id] = shadow;
    return shadow_id;
}

void HydraShadowBufferManager::UpdateDirectionalShadow(HydraID shadow_id, HydraDirectionalShadowSourceComponent shadow)
{
    std::lock_guard<std::mutex> lock(m_mutex);
    if(shadow_id < MAX_DIRECTIONAL_SHADOWS)
    {
        m_directional_shadow_buffer[shadow_id] = shadow;
    }
}

void HydraShadowBufferManager::UpdateSpotShadow(HydraID shadow_id, HydraSpotShadowSourceComponent shadow)
{
        std::lock_guard<std::mutex> lock(m_mutex);
    if(shadow_id < MAX_SPOT_SHADOWS)
    {
        m_spot_shadow_buffer[shadow_id] = shadow;
    }
}

void HydraShadowBufferManager::RemoveDirectionalShadow(HydraID shadow_id)
{

}
void HydraShadowBufferManager::RemoveSpotShadow(HydraID shadow_id)
{

}

void HydraShadowBufferManager::UpdateShadowBuffer()
{
    HydraEngine *engine = GetEngine();
    HydraECS *ecs = engine->ECS();

    HydraTaskScheduler *task_scheduler = GetEngine()->TaskScheduler();
    void *buffer = static_cast<void *>(m_directional_shadow_buffer.data());

    HydraID update_buffer_task_id = task_scheduler->CreateTask<HydraUpdateWholeGPUBufferTask>(HydraThreadAffinity::Render);
    HydraUpdateWholeGPUBufferTask *task = static_cast<HydraUpdateWholeGPUBufferTask *>(task_scheduler->GetTask(update_buffer_task_id));
    task->Intialise(m_directional_shadow_buffer_id,  buffer);
    task_scheduler->WaitForTask(update_buffer_task_id);

    void *spot_buffer = static_cast<void *>(m_spot_shadow_buffer.data());

    update_buffer_task_id = task_scheduler->CreateTask<HydraUpdateWholeGPUBufferTask>(HydraThreadAffinity::Render);
    HydraUpdateWholeGPUBufferTask *spot_task = static_cast<HydraUpdateWholeGPUBufferTask *>(task_scheduler->GetTask(update_buffer_task_id));
    spot_task->Intialise(m_spot_shadow_buffer_id,  spot_buffer);
    task_scheduler->WaitForTask(update_buffer_task_id);
}