#include "metal_presentation_queue.h"
#include "surface/metal_surface.h"
#include "devices/metal_output_devices.h"
#include "texture/metal_texture.h"
#include "sync/semaphore/metal_semaphore.h"

gnReturnCode createMetalPresentationQueue(gnPresentationQueueHandle presentationQueue, const gnDevice device, gnPresentationQueueInfo presentationInfo) {
    presentationQueue->presentationQueue = malloc(sizeof(struct gnPlatformPresentationQueue_t));
    presentationQueue->presentationQueue->createdSize.x = presentationInfo.surface->windowSurface->layer.visibleRect.size.width;
    presentationQueue->presentationQueue->createdSize.y = presentationInfo.surface->windowSurface->layer.visibleRect.size.height;

    MTLPixelFormat convertedFormat = mtlGryphnFormatToMetalFormat(presentationInfo.format.format);

    MTLTextureDescriptor* textureDescriptor = [[MTLTextureDescriptor alloc] init];
    textureDescriptor.pixelFormat = convertedFormat;
    textureDescriptor.width = presentationInfo.imageSize.x;
    textureDescriptor.height = presentationInfo.imageSize.y;
    textureDescriptor.usage = MTLTextureUsageRenderTarget | MTLTextureUsageShaderRead;
    textureDescriptor.sampleCount = 1;
    textureDescriptor.textureType  = MTLTextureType2D;

    presentationQueue->imageCount = presentationInfo.minImageCount;
    presentationQueue->images = malloc(sizeof(gnTexture) * presentationInfo.minImageCount);
    presentationQueue->presentationQueue->textures = metalTextureArrayListCreate();
    presentationQueue->presentationQueue->avaliableTextures = uint32_tArrayListCreate();
    for (int i = 0; i < presentationInfo.minImageCount; i++) {
        presentationQueue->images[i] = malloc(sizeof(struct gnTexture_t));
        presentationQueue->images[i]->texture = malloc(sizeof(gnPlatformTexture));
        presentationQueue->images[i]->texture->texture = [device->outputDevice->device newTextureWithDescriptor:textureDescriptor];
        metalTextureArrayListAdd(&presentationQueue->presentationQueue->textures, presentationQueue->images[i]->texture->texture);
        uint32_tArrayListAdd(&presentationQueue->presentationQueue->avaliableTextures, i);
    }
    [textureDescriptor release];

    return GN_SUCCESS;
}

void mtlTakeImageFromQueue(uint32_t* whereToPut, gnPresentationQueue queue, gnSemaphore semaphore) {
    *whereToPut = queue->presentationQueue->avaliableTextures.data[0];
    uint32_tArrayListPopHead(&queue->presentationQueue->avaliableTextures);

    if (!semaphore) return;

    id<MTLCommandBuffer> buffer = [queue->outputDevice->outputDevice->transferQueue commandBuffer];
    mtlSignalSemaphore(semaphore, buffer);
    [buffer commit];
}

void mtlAddImageBackToQueue(gnPresentationQueue queue, uint32_t index) {
    if (queue->presentationQueue->neededImages.count > 0) {
        mtlTakeImageFromQueue(queue->presentationQueue->neededImages.data[queue->presentationQueue->neededImages.count - 1].whereToPut, queue, queue->presentationQueue->neededImages.data[queue->presentationQueue->neededImages.count - 1].semaphoreToSignal);
        mtlImageNeededArrayListRemove(&queue->presentationQueue->neededImages);
    }
    else
        uint32_tArrayListAdd(&queue->presentationQueue->avaliableTextures, index);
}

gnReturnCode getMetalPresentQueueImageAsync(gnPresentationQueueHandle presentationQueue, uint64_t timeout, gnSemaphore semaphore, uint32_t* imageIndex) {
    while(presentationQueue->presentationQueue->avaliableTextures.count == 0);
    mtlTakeImageFromQueue(imageIndex, presentationQueue, semaphore);

    CGSize currentSize = presentationQueue->info.surface->windowSurface->layer.visibleRect.size;
    if (currentSize.width  != presentationQueue->presentationQueue->createdSize.x ||
        currentSize.height != presentationQueue->presentationQueue->createdSize.y) return GN_SUBOPTIMAL_PRESENTATION_QUEUE;

    return GN_SUCCESS;
}

gnReturnCode getMetalPresentQueueImage(gnPresentationQueueHandle presentationQueue, uint32_t* imageIndex) {
    while (presentationQueue->presentationQueue->avaliableTextures.count == 0) {}
    mtlTakeImageFromQueue(imageIndex, presentationQueue, NULL);

    CGSize currentSize = presentationQueue->info.surface->windowSurface->layer.visibleRect.size;
    if (currentSize.width  != presentationQueue->presentationQueue->createdSize.x ||
        currentSize.height != presentationQueue->presentationQueue->createdSize.y) return GN_SUBOPTIMAL_PRESENTATION_QUEUE;

    return GN_SUCCESS;
}

void destroyMetalPresentationQueue(gnPresentationQueueHandle presentationQueue) {
    free(presentationQueue->presentationQueue->avaliableTextures.data);
    presentationQueue->presentationQueue->avaliableTextures.count = 0;
    for (int i = 0; i < presentationQueue->imageCount; i++) {
        [presentationQueue->images[i]->texture->texture release];
        free(presentationQueue->images[i]->texture);
        free(presentationQueue->images[i]);
    }
    free(presentationQueue->presentationQueue);
}