/*
 * GStreamer
 * Copyright (C) 2016 Matthew Waters <matthew@centricular.com>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 */

/**
 * SECTION:element-vulkanupload
 * @title: vulkanupload
 *
 * vulkanupload uploads data into Vulkan memory objects.
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <string.h>
#include "gstvulkanelements.h"
#include "gstvkutils.h"
#include "vkupload.h"

GST_DEBUG_CATEGORY (gst_debug_vulkan_upload);
#define GST_CAT_DEFAULT gst_debug_vulkan_upload

static GstCaps *
_set_caps_features_with_passthrough (const GstCaps * caps,
    const gchar * feature_name, GstCapsFeatures * passthrough)
{
  guint i, j, m, n;
  GstCaps *tmp;

  tmp = gst_caps_copy (caps);

  n = gst_caps_get_size (caps);
  for (i = 0; i < n; i++) {
    GstCapsFeatures *features, *orig_features;

    orig_features = gst_caps_get_features (caps, i);
    features = gst_caps_features_new_static_str (feature_name, NULL);

    m = gst_caps_features_get_size (orig_features);
    for (j = 0; j < m; j++) {
      const gchar *feature = gst_caps_features_get_nth (orig_features, j);

      /* if we already have the features */
      if (gst_caps_features_contains (features, feature))
        continue;

      if (g_strcmp0 (feature, GST_CAPS_FEATURE_MEMORY_SYSTEM_MEMORY) == 0)
        continue;

      if (passthrough && gst_caps_features_contains (passthrough, feature)) {
        gst_caps_features_add (features, feature);
      }
    }

    gst_caps_set_features (tmp, i, features);
  }

  return tmp;
}

struct BufferUpload
{
  GstVulkanUpload *upload;
};

static gpointer
_buffer_new_impl (GstVulkanUpload * upload)
{
  struct BufferUpload *raw = g_new0 (struct BufferUpload, 1);

  raw->upload = upload;

  return raw;
}

static GstCaps *
_buffer_transform_caps (gpointer impl, GstPadDirection direction,
    GstCaps * caps)
{
  return gst_caps_ref (caps);
}

static gboolean
_buffer_set_caps (gpointer impl, GstCaps * in_caps, GstCaps * out_caps)
{
  return TRUE;
}

static void
_buffer_propose_allocation (gpointer impl, GstQuery * decide_query,
    GstQuery * query)
{
  struct BufferUpload *raw = impl;
  gboolean need_pool;
  GstCaps *caps;
  GstVideoInfo info;
  guint size;
  GstBufferPool *pool = NULL;

  gst_query_parse_allocation (query, &caps, &need_pool);

  if (caps == NULL)
    return;

  if (!gst_video_info_from_caps (&info, caps))
    return;

  /* the normal size of a frame */
  size = info.size;

  if (need_pool) {
    GstStructure *config;

    pool = gst_vulkan_buffer_pool_new (raw->upload->device);

    config = gst_buffer_pool_get_config (pool);
    gst_buffer_pool_config_set_params (config, caps, size, 0, 0);

    if (!gst_buffer_pool_set_config (pool, config)) {
      g_object_unref (pool);
      return;
    }
  }

  gst_query_add_allocation_pool (query, pool, size, 1, 0);
  if (pool)
    g_object_unref (pool);

  return;
}

static GstFlowReturn
_buffer_perform (gpointer impl, GstBuffer * inbuf, GstBuffer ** outbuf)
{
  if (!gst_is_vulkan_buffer_memory (gst_buffer_peek_memory (inbuf, 0)))
    return GST_FLOW_ERROR;

  *outbuf = inbuf;

  return GST_FLOW_OK;
}

static void
_buffer_free (gpointer impl)
{
  g_free (impl);
}

static GstStaticCaps _buffer_in_templ =
    GST_STATIC_CAPS ("video/x-raw(" GST_CAPS_FEATURE_MEMORY_VULKAN_BUFFER ") ;"
    "video/x-raw");
static GstStaticCaps _buffer_out_templ =
GST_STATIC_CAPS ("video/x-raw(" GST_CAPS_FEATURE_MEMORY_VULKAN_BUFFER ")");

static const struct UploadMethod buffer_upload = {
  "VulkanBuffer",
  &_buffer_in_templ,
  &_buffer_out_templ,
  _buffer_new_impl,
  _buffer_transform_caps,
  _buffer_set_caps,
  _buffer_propose_allocation,
  _buffer_perform,
  _buffer_free,
};

struct RawToBufferUpload
{
  GstVulkanUpload *upload;

  GstVideoInfo in_info;
  GstVideoInfo out_info;
};

static gpointer
_raw_to_buffer_new_impl (GstVulkanUpload * upload)
{
  struct RawToBufferUpload *raw = g_new0 (struct RawToBufferUpload, 1);

  raw->upload = upload;

  return raw;
}

static GstCaps *
_raw_to_buffer_transform_caps (gpointer impl, GstPadDirection direction,
    GstCaps * caps)
{
  GstCaps *ret;

  if (direction == GST_PAD_SINK) {
    ret =
        _set_caps_features_with_passthrough (caps,
        GST_CAPS_FEATURE_MEMORY_VULKAN_BUFFER, NULL);
  } else {
    ret =
        _set_caps_features_with_passthrough (caps,
        GST_CAPS_FEATURE_MEMORY_SYSTEM_MEMORY, NULL);
  }

  return ret;
}

static gboolean
_raw_to_buffer_set_caps (gpointer impl, GstCaps * in_caps, GstCaps * out_caps)
{
  struct RawToBufferUpload *raw = impl;

  if (!gst_video_info_from_caps (&raw->in_info, in_caps))
    return FALSE;

  if (!gst_video_info_from_caps (&raw->out_info, out_caps))
    return FALSE;

  return TRUE;
}

static void
_raw_to_buffer_propose_allocation (gpointer impl, GstQuery * decide_query,
    GstQuery * query)
{
  /* a little trickery with the impl pointer */
  _buffer_propose_allocation (impl, decide_query, query);
}

static gboolean
_copy_frames (const GstVideoInfo * vinfo, GstBuffer * inbuf, GstBuffer * outbuf)
{
  GstVideoFrame in_frame, out_frame;
  gboolean copied;

  if (!gst_video_frame_map (&in_frame, vinfo, inbuf, GST_MAP_READ))
    return FALSE;

  if (!gst_video_frame_map (&out_frame, vinfo, outbuf, GST_MAP_WRITE)) {
    gst_video_frame_unmap (&in_frame);
    return FALSE;
  }

  copied = gst_video_frame_copy (&out_frame, &in_frame);

  gst_video_frame_unmap (&in_frame);
  gst_video_frame_unmap (&out_frame);

  return copied;
}

static GstFlowReturn
_raw_to_buffer_perform (gpointer impl, GstBuffer * inbuf, GstBuffer ** outbuf)
{
  struct RawToBufferUpload *raw = impl;
  GstFlowReturn ret = GST_FLOW_ERROR;
  GstBufferPool *pool;

  pool = gst_base_transform_get_buffer_pool
      (GST_BASE_TRANSFORM_CAST (raw->upload));
  if (!pool)
    return GST_FLOW_ERROR;

  gst_buffer_pool_set_active (pool, TRUE);
  if ((ret = gst_buffer_pool_acquire_buffer (pool, outbuf, NULL))
      != GST_FLOW_OK)
    goto out;

  if (!_copy_frames (&raw->in_info, inbuf, *outbuf)) {
    GST_ELEMENT_ERROR (raw->upload, RESOURCE, NOT_FOUND,
        ("%s", "Failed to map input buffer"), NULL);
    ret = GST_FLOW_ERROR;
  }

out:
  gst_object_unref (pool);
  return ret;
}

static void
_raw_to_buffer_free (gpointer impl)
{
  g_free (impl);
}

static GstStaticCaps _raw_to_buffer_in_templ = GST_STATIC_CAPS ("video/x-raw");
static GstStaticCaps _raw_to_buffer_out_templ =
GST_STATIC_CAPS ("video/x-raw(" GST_CAPS_FEATURE_MEMORY_VULKAN_BUFFER ")");

static const struct UploadMethod raw_to_buffer_upload = {
  "RawToVulkanBuffer",
  &_raw_to_buffer_in_templ,
  &_raw_to_buffer_out_templ,
  _raw_to_buffer_new_impl,
  _raw_to_buffer_transform_caps,
  _raw_to_buffer_set_caps,
  _raw_to_buffer_propose_allocation,
  _raw_to_buffer_perform,
  _raw_to_buffer_free,
};

struct BufferToImageUpload
{
  GstVulkanUpload *upload;

  GstVideoInfo in_info;
  GstVideoInfo out_info;

  GstVulkanOperation *exec;
};

static gpointer
_buffer_to_image_new_impl (GstVulkanUpload * upload)
{
  struct BufferToImageUpload *raw = g_new0 (struct BufferToImageUpload, 1);

  raw->upload = upload;

  return raw;
}

static GstCaps *
_buffer_to_image_transform_caps (gpointer impl, GstPadDirection direction,
    GstCaps * caps)
{
  GstCaps *ret;

  if (direction == GST_PAD_SINK) {
    ret =
        _set_caps_features_with_passthrough (caps,
        GST_CAPS_FEATURE_MEMORY_VULKAN_IMAGE, NULL);
  } else {
    ret =
        _set_caps_features_with_passthrough (caps,
        GST_CAPS_FEATURE_MEMORY_VULKAN_BUFFER, NULL);
  }

  return ret;
}

static gboolean
_buffer_to_image_set_caps (gpointer impl, GstCaps * in_caps, GstCaps * out_caps)
{
  struct BufferToImageUpload *raw = impl;

  if (!gst_video_info_from_caps (&raw->in_info, in_caps))
    return FALSE;

  if (!gst_video_info_from_caps (&raw->out_info, out_caps))
    return FALSE;

  return TRUE;
}

static void
_buffer_to_image_propose_allocation (gpointer impl, GstQuery * decide_query,
    GstQuery * query)
{
  /* a little trickery with the impl pointer */
  _buffer_propose_allocation (impl, decide_query, query);
}

static GstFlowReturn
_buffer_to_image_perform (gpointer impl, GstBuffer * inbuf, GstBuffer ** outbuf)
{
  struct BufferToImageUpload *raw = impl;
  GstFlowReturn ret;
  GError *error = NULL;
  GstVulkanCommandBuffer *cmd_buf;
  guint i, n_mems, n_planes;
  GArray *barriers = NULL;
  VkImageLayout dst_layout = VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL;
  GstBufferPool *pool;

  pool = gst_base_transform_get_buffer_pool
      (GST_BASE_TRANSFORM_CAST (raw->upload));
  if (!pool)
    return GST_FLOW_ERROR;

  gst_buffer_pool_set_active (pool, TRUE);
  if ((ret = gst_buffer_pool_acquire_buffer (pool, outbuf, NULL))
      != GST_FLOW_OK)
    goto out;

  if (!raw->exec) {
    GstVulkanCommandPool *cmd_pool =
        gst_vulkan_queue_create_command_pool (raw->upload->queue, &error);
    if (!cmd_pool)
      goto error;

    raw->exec = gst_vulkan_operation_new (cmd_pool);
    gst_object_unref (cmd_pool);
  }

  if (!gst_vulkan_operation_add_dependency_frame (raw->exec, *outbuf,
          VK_PIPELINE_STAGE_ALL_COMMANDS_BIT, VK_PIPELINE_STAGE_TRANSFER_BIT))
    goto error;

  if (!gst_vulkan_operation_begin (raw->exec, &error))
    goto error;

  cmd_buf = raw->exec->cmd_buf;

  if (!gst_vulkan_operation_add_frame_barrier (raw->exec, *outbuf,
          VK_PIPELINE_STAGE_ALL_COMMANDS_BIT, VK_PIPELINE_STAGE_TRANSFER_BIT,
          VK_ACCESS_TRANSFER_WRITE_BIT, VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL,
          NULL))
    goto unlock_error;

  barriers = gst_vulkan_operation_retrieve_image_barriers (raw->exec);
  if (barriers->len == 0) {
    ret = GST_FLOW_ERROR;
    goto unlock_error;
  }

  if (gst_vulkan_operation_use_sync2 (raw->exec)) {
#if defined(VK_KHR_synchronization2)
    VkDependencyInfoKHR dependency_info = {
      .sType = VK_STRUCTURE_TYPE_DEPENDENCY_INFO_KHR,
      .pImageMemoryBarriers = (gpointer) barriers->data,
      .imageMemoryBarrierCount = barriers->len,
    };

    gst_vulkan_operation_pipeline_barrier2 (raw->exec, &dependency_info);
    dst_layout =
        g_array_index (barriers, VkImageMemoryBarrier2KHR, 0).newLayout;
#endif
  } else {
    gst_vulkan_command_buffer_lock (cmd_buf);
    vkCmdPipelineBarrier (cmd_buf->cmd, VK_PIPELINE_STAGE_ALL_COMMANDS_BIT,
        VK_PIPELINE_STAGE_TRANSFER_BIT, 0, 0, NULL, 0, NULL,
        barriers->len, (gpointer) barriers->data);
    gst_vulkan_command_buffer_unlock (cmd_buf);

    dst_layout = g_array_index (barriers, VkImageMemoryBarrier, 0).newLayout;
  }
  g_clear_pointer (&barriers, g_array_unref);

  n_mems = gst_buffer_n_memory (*outbuf);
  n_planes = GST_VIDEO_INFO_N_PLANES (&raw->out_info);

  for (i = 0; i < n_planes; i++) {
    VkBufferImageCopy region;
    GstMemory *mem;
    GstVulkanBufferMemory *buf_mem;
    GstVulkanImageMemory *img_mem;
    const VkImageAspectFlags aspects[] = { VK_IMAGE_ASPECT_PLANE_0_BIT,
      VK_IMAGE_ASPECT_PLANE_1_BIT, VK_IMAGE_ASPECT_PLANE_2_BIT,
    };
    VkImageAspectFlags plane_aspect;
    guint32 width, height, row, img_h;

    mem = gst_vulkan_buffer_peek_plane_memory (inbuf, &raw->in_info, i);
    if (!mem)
      goto unlock_error;
    if (!gst_is_vulkan_buffer_memory (mem)) {
      GST_WARNING_OBJECT (raw->upload, "Input buffer is not a Vulkan buffer");
      goto unlock_error;
    }
    buf_mem = (GstVulkanBufferMemory *) mem;

    if (n_planes == n_mems)
      plane_aspect = VK_IMAGE_ASPECT_COLOR_BIT;
    else
      plane_aspect = aspects[i];

    gst_vulkan_buffer_get_plane_dimensions (inbuf, &raw->in_info, i, &width,
        &height, &row, &img_h);

    /* *INDENT-OFF* */
    region = (VkBufferImageCopy) {
      .bufferOffset = 0,
      .bufferRowLength = row,
      .bufferImageHeight = img_h,
      .imageSubresource = {
        .aspectMask = plane_aspect,
        .mipLevel = 0,
        .baseArrayLayer = 0,
        .layerCount = 1,
      },
      .imageOffset = { .x = 0, .y = 0, .z = 0, },
      .imageExtent = {
        .width = width,
        .height = height,
        .depth = 1,
      }
    };
    /* *INDENT-ON* */

    mem = gst_vulkan_buffer_peek_plane_memory (*outbuf, &raw->out_info, i);
    if (!mem)
      goto unlock_error;
    if (!gst_is_vulkan_image_memory (mem)) {
      GST_WARNING_OBJECT (raw->upload, "Output buffer is not a Vulkan image");
      goto unlock_error;
    }
    img_mem = (GstVulkanImageMemory *) mem;

    gst_vulkan_command_buffer_lock (cmd_buf);
    vkCmdCopyBufferToImage (cmd_buf->cmd, buf_mem->buffer, img_mem->image,
        dst_layout, 1, &region);
    gst_vulkan_command_buffer_unlock (cmd_buf);
  }

  if (!gst_vulkan_operation_end (raw->exec, &error))
    goto error;

  ret = GST_FLOW_OK;

out:
  gst_object_unref (pool);
  return ret;

unlock_error:
  gst_vulkan_operation_reset (raw->exec);

error:
  if (error) {
    GST_WARNING_OBJECT (raw->upload, "Error: %s", error->message);
    g_clear_error (&error);
  }
  gst_clear_buffer (outbuf);
  ret = GST_FLOW_ERROR;
  goto out;
}

static void
_buffer_to_image_free (gpointer impl)
{
  struct BufferToImageUpload *raw = impl;

  if (raw->exec) {
    if (!gst_vulkan_operation_wait (raw->exec)) {
      GST_WARNING_OBJECT (raw->upload,
          "Failed to wait for all fences to complete before shutting down");
    }
    gst_object_unref (raw->exec);
    raw->exec = NULL;
  }

  g_free (impl);
}

static GstStaticCaps _buffer_to_image_in_templ =
GST_STATIC_CAPS ("video/x-raw(" GST_CAPS_FEATURE_MEMORY_VULKAN_BUFFER ")");
static GstStaticCaps _buffer_to_image_out_templ =
GST_STATIC_CAPS ("video/x-raw(" GST_CAPS_FEATURE_MEMORY_VULKAN_IMAGE ")");

static const struct UploadMethod buffer_to_image_upload = {
  "BufferToVulkanImage",
  &_buffer_to_image_in_templ,
  &_buffer_to_image_out_templ,
  _buffer_to_image_new_impl,
  _buffer_to_image_transform_caps,
  _buffer_to_image_set_caps,
  _buffer_to_image_propose_allocation,
  _buffer_to_image_perform,
  _buffer_to_image_free,
};

struct RawToImageUpload
{
  GstVulkanUpload *upload;

  GstVideoInfo in_info;
  GstVideoInfo out_info;

  GstBufferPool *in_pool;
  gboolean in_pool_active;

  GstVulkanOperation *exec;
};

static gpointer
_raw_to_image_new_impl (GstVulkanUpload * upload)
{
  struct RawToImageUpload *raw = g_new0 (struct RawToImageUpload, 1);

  raw->upload = upload;

  return raw;
}

static GstCaps *
_raw_to_image_transform_caps (gpointer impl, GstPadDirection direction,
    GstCaps * caps)
{
  GstCaps *ret;

  if (direction == GST_PAD_SINK) {
    ret =
        _set_caps_features_with_passthrough (caps,
        GST_CAPS_FEATURE_MEMORY_VULKAN_IMAGE, NULL);
  } else {
    ret =
        _set_caps_features_with_passthrough (caps,
        GST_CAPS_FEATURE_MEMORY_SYSTEM_MEMORY, NULL);
  }

  return ret;
}

static gboolean
_raw_to_image_set_caps (gpointer impl, GstCaps * in_caps, GstCaps * out_caps)
{
  struct RawToImageUpload *raw = impl;

  if (!gst_video_info_from_caps (&raw->in_info, in_caps))
    return FALSE;

  if (!gst_video_info_from_caps (&raw->out_info, out_caps))
    return FALSE;

  if (raw->in_pool) {
    if (raw->in_pool_active) {
      gst_buffer_pool_set_active (raw->in_pool, FALSE);
    }
    raw->in_pool_active = FALSE;
    gst_object_unref (raw->in_pool);
    raw->in_pool = NULL;
  }

  return TRUE;
}

static void
_raw_to_image_propose_allocation (gpointer impl, GstQuery * decide_query,
    GstQuery * query)
{
  /* a little trickery with the impl pointer */
  _buffer_propose_allocation (impl, decide_query, query);
}

static GstFlowReturn
_raw_to_image_perform (gpointer impl, GstBuffer * inbuf, GstBuffer ** outbuf)
{
  struct RawToImageUpload *raw = impl;
  GstFlowReturn ret;
  GstBuffer *in_vk_copy = NULL;
  GstVulkanCommandBuffer *cmd_buf;
  GError *error = NULL;
  GArray *barriers = NULL;
  guint i, n_planes, n_out_mems;
  VkImageLayout dst_layout = VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL;
  GstBufferPool *pool;

  pool = gst_base_transform_get_buffer_pool
      (GST_BASE_TRANSFORM_CAST (raw->upload));
  if (!pool)
    return GST_FLOW_ERROR;

  gst_buffer_pool_set_active (pool, TRUE);
  if ((ret = gst_buffer_pool_acquire_buffer (pool, outbuf, NULL))
      != GST_FLOW_OK)
    goto out;

  if (!raw->exec) {
    GstVulkanCommandPool *cmd_pool =
        gst_vulkan_queue_create_command_pool (raw->upload->queue, &error);

    raw->exec = gst_vulkan_operation_new (cmd_pool);
    gst_object_unref (cmd_pool);
  }

  if (!gst_vulkan_operation_begin (raw->exec, &error))
    goto error;

  if (!gst_vulkan_operation_add_dependency_frame (raw->exec, *outbuf,
          VK_PIPELINE_STAGE_ALL_COMMANDS_BIT, VK_PIPELINE_STAGE_TRANSFER_BIT))
    goto unlock_error;

  cmd_buf = raw->exec->cmd_buf;

  if (!gst_vulkan_operation_add_frame_barrier (raw->exec, *outbuf,
          VK_PIPELINE_STAGE_ALL_COMMANDS_BIT, VK_PIPELINE_STAGE_TRANSFER_BIT,
          VK_ACCESS_TRANSFER_WRITE_BIT, VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL,
          NULL))
    goto unlock_error;

  barriers = gst_vulkan_operation_retrieve_image_barriers (raw->exec);
  if (barriers->len == 0) {
    ret = GST_FLOW_ERROR;
    goto unlock_error;
  }

  if (gst_vulkan_operation_use_sync2 (raw->exec)) {
#if defined(VK_KHR_synchronization2)
    VkDependencyInfoKHR dependency_info = {
      .sType = VK_STRUCTURE_TYPE_DEPENDENCY_INFO_KHR,
      .pImageMemoryBarriers = (gpointer) barriers->data,
      .imageMemoryBarrierCount = barriers->len,
    };

    gst_vulkan_operation_pipeline_barrier2 (raw->exec, &dependency_info);
    dst_layout =
        g_array_index (barriers, VkImageMemoryBarrier2KHR, 0).newLayout;
#endif
  } else {
    gst_vulkan_command_buffer_lock (cmd_buf);
    vkCmdPipelineBarrier (cmd_buf->cmd, VK_PIPELINE_STAGE_ALL_COMMANDS_BIT,
        VK_PIPELINE_STAGE_TRANSFER_BIT, 0, 0, NULL, 0, NULL,
        barriers->len, (gpointer) barriers->data);
    gst_vulkan_command_buffer_unlock (cmd_buf);

    dst_layout = g_array_index (barriers, VkImageMemoryBarrier, 0).newLayout;
  }
  g_clear_pointer (&barriers, g_array_unref);

  n_out_mems = gst_buffer_n_memory (*outbuf);
  n_planes = GST_VIDEO_INFO_N_PLANES (&raw->in_info);

  for (i = 0; i < n_planes; i++) {
    VkBufferImageCopy region;
    GstBuffer *used_buf = inbuf;
    GstMemory *mem;
    GstVulkanBufferMemory *buf_mem;
    GstVulkanImageMemory *img_mem;
    const VkImageAspectFlags aspects[] = { VK_IMAGE_ASPECT_PLANE_0_BIT,
      VK_IMAGE_ASPECT_PLANE_1_BIT, VK_IMAGE_ASPECT_PLANE_2_BIT,
    };
    VkImageAspectFlags plane_aspect;
    guint32 width, height, row, img_h;

    mem = gst_vulkan_buffer_peek_plane_memory (inbuf, &raw->in_info, i);
    if (!mem)
      goto unlock_error;

    if (gst_is_vulkan_buffer_memory (mem)) {
      GST_TRACE_OBJECT (raw->upload, "Input is a GstVulkanBufferMemory");
    } else if (in_vk_copy) {
      GST_TRACE_OBJECT (raw->upload,
          "Have buffer copy of GstVulkanBufferMemory");
      used_buf = in_vk_copy;
      mem = gst_buffer_peek_memory (in_vk_copy, i);
      g_assert (gst_is_vulkan_buffer_memory (mem));
    } else {
      GST_TRACE_OBJECT (raw->upload,
          "Copying input to a new GstVulkanBufferMemory");
      if (!raw->in_pool) {
        GstStructure *config;
        guint min = 0, max = 0;
        gsize size = 1;

        raw->in_pool = gst_vulkan_buffer_pool_new (raw->upload->device);
        config = gst_buffer_pool_get_config (raw->in_pool);
        gst_buffer_pool_config_set_params (config, raw->upload->in_caps, size,
            min, max);
        gst_buffer_pool_set_config (raw->in_pool, config);
      }
      if (!raw->in_pool_active) {
        gst_buffer_pool_set_active (raw->in_pool, TRUE);
        raw->in_pool_active = TRUE;
      }

      if ((ret =
              gst_buffer_pool_acquire_buffer (raw->in_pool, &in_vk_copy,
                  NULL)) != GST_FLOW_OK) {
        goto unlock_error;
      }

      if (!_copy_frames (&raw->in_info, inbuf, in_vk_copy)) {
        GST_ERROR_OBJECT (raw->upload, "Failed to copy to Vulkan buffer");
        goto unlock_error;
      }

      used_buf = in_vk_copy;
      mem = gst_buffer_peek_memory (in_vk_copy, i);
    }

    buf_mem = (GstVulkanBufferMemory *) mem;

    mem = gst_vulkan_buffer_peek_plane_memory (*outbuf, &raw->out_info, i);
    if (!mem)
      goto unlock_error;
    if (!gst_is_vulkan_image_memory (mem)) {
      GST_WARNING_OBJECT (raw->upload, "Output buffer is not a Vulkan image");
      goto unlock_error;
    }
    img_mem = (GstVulkanImageMemory *) mem;

    if (n_planes == n_out_mems)
      plane_aspect = VK_IMAGE_ASPECT_COLOR_BIT;
    else
      plane_aspect = aspects[i];

    gst_vulkan_buffer_get_plane_dimensions (used_buf, &raw->in_info, i, &width,
        &height, &row, &img_h);

    /* *INDENT-OFF* */
    region = (VkBufferImageCopy) {
      .bufferOffset = 0,
      .bufferRowLength = row,
      .bufferImageHeight = img_h,
      .imageSubresource = {
        .aspectMask = plane_aspect,
        .mipLevel = 0,
        .baseArrayLayer = 0,
        .layerCount = 1,
      },
      .imageOffset = { .x = 0, .y = 0, .z = 0, },
      .imageExtent = {
        .width = width,
        .height = height,
        .depth = 1,
      }
    };
    /* *INDENT-ON* */

    gst_vulkan_command_buffer_lock (cmd_buf);
    vkCmdCopyBufferToImage (cmd_buf->cmd, buf_mem->buffer, img_mem->image,
        dst_layout, 1, &region);
    gst_vulkan_command_buffer_unlock (cmd_buf);
  }

  if (!gst_vulkan_operation_end (raw->exec, &error))
    goto error;

  ret = GST_FLOW_OK;

out:
  gst_object_unref (pool);
  if (in_vk_copy)
    gst_buffer_unref (in_vk_copy);

  return ret;

unlock_error:
  gst_vulkan_operation_reset (raw->exec);

error:
  if (error) {
    GST_WARNING_OBJECT (raw->upload, "Error: %s", error->message);
    g_clear_error (&error);
  }
  gst_clear_buffer (outbuf);
  ret = GST_FLOW_ERROR;
  goto out;
}

static void
_raw_to_image_free (gpointer impl)
{
  struct RawToImageUpload *raw = impl;

  if (raw->in_pool) {
    if (raw->in_pool_active) {
      gst_buffer_pool_set_active (raw->in_pool, FALSE);
    }
    raw->in_pool_active = FALSE;
    gst_object_unref (raw->in_pool);
    raw->in_pool = NULL;
  }

  if (raw->exec) {
    if (!gst_vulkan_operation_wait (raw->exec)) {
      GST_WARNING_OBJECT (raw->upload,
          "Failed to wait for all fences to complete before shutting down");
    }
    gst_object_unref (raw->exec);
    raw->exec = NULL;
  }

  g_free (impl);
}

static GstStaticCaps _raw_to_image_in_templ = GST_STATIC_CAPS ("video/x-raw");
static GstStaticCaps _raw_to_image_out_templ =
GST_STATIC_CAPS ("video/x-raw(" GST_CAPS_FEATURE_MEMORY_VULKAN_IMAGE ")");

static const struct UploadMethod raw_to_image_upload = {
  "RawToVulkanImage",
  &_raw_to_image_in_templ,
  &_raw_to_image_out_templ,
  _raw_to_image_new_impl,
  _raw_to_image_transform_caps,
  _raw_to_image_set_caps,
  _raw_to_image_propose_allocation,
  _raw_to_image_perform,
  _raw_to_image_free,
};

static const struct UploadMethod *upload_methods[] = {
  &buffer_upload,
  &raw_to_buffer_upload,
  &raw_to_image_upload,
  &buffer_to_image_upload,
};

static GstCaps *
_get_input_template_caps (void)
{
  GstCaps *ret = NULL;
  gint i;

  /* FIXME: cache this and invalidate on changes to upload_methods */
  for (i = 0; i < G_N_ELEMENTS (upload_methods); i++) {
    GstCaps *template = gst_static_caps_get (upload_methods[i]->in_template);
    ret = ret == NULL ? template : gst_caps_merge (ret, template);
  }

  ret = gst_caps_simplify (ret);

  return ret;
}

static GstCaps *
_get_output_template_caps (void)
{
  GstCaps *ret = NULL;
  gint i;

  /* FIXME: cache this and invalidate on changes to upload_methods */
  for (i = 0; i < G_N_ELEMENTS (upload_methods); i++) {
    GstCaps *template = gst_static_caps_get (upload_methods[i]->out_template);
    ret = ret == NULL ? template : gst_caps_merge (ret, template);
  }

  ret = gst_caps_simplify (ret);

  return ret;
}

static void gst_vulkan_upload_finalize (GObject * object);
static void gst_vulkan_upload_set_property (GObject * object, guint prop_id,
    const GValue * value, GParamSpec * param_spec);
static void gst_vulkan_upload_get_property (GObject * object, guint prop_id,
    GValue * value, GParamSpec * param_spec);

static gboolean gst_vulkan_upload_query (GstBaseTransform * bt,
    GstPadDirection direction, GstQuery * query);
static void gst_vulkan_upload_set_context (GstElement * element,
    GstContext * context);
static GstStateChangeReturn gst_vulkan_upload_change_state (GstElement *
    element, GstStateChange transition);

static gboolean gst_vulkan_upload_set_caps (GstBaseTransform * bt,
    GstCaps * in_caps, GstCaps * out_caps);
static GstCaps *gst_vulkan_upload_transform_caps (GstBaseTransform * bt,
    GstPadDirection direction, GstCaps * caps, GstCaps * filter);
static gboolean gst_vulkan_upload_propose_allocation (GstBaseTransform * bt,
    GstQuery * decide_query, GstQuery * query);
static gboolean gst_vulkan_upload_decide_allocation (GstBaseTransform * bt,
    GstQuery * query);
static GstFlowReturn gst_vulkan_upload_transform (GstBaseTransform * bt,
    GstBuffer * inbuf, GstBuffer * outbuf);
static GstFlowReturn gst_vulkan_upload_prepare_output_buffer (GstBaseTransform *
    bt, GstBuffer * inbuf, GstBuffer ** outbuf);

enum
{
  PROP_0,
};

enum
{
  SIGNAL_0,
  LAST_SIGNAL
};

/* static guint gst_vulkan_upload_signals[LAST_SIGNAL] = { 0 }; */

#define gst_vulkan_upload_parent_class parent_class
G_DEFINE_TYPE_WITH_CODE (GstVulkanUpload, gst_vulkan_upload,
    GST_TYPE_BASE_TRANSFORM, GST_DEBUG_CATEGORY_INIT (gst_debug_vulkan_upload,
        "vulkanupload", 0, "Vulkan Uploader"));
GST_ELEMENT_REGISTER_DEFINE_WITH_CODE (vulkanupload, "vulkanupload",
    GST_RANK_NONE, GST_TYPE_VULKAN_UPLOAD, vulkan_element_init (plugin));

static void
gst_vulkan_upload_class_init (GstVulkanUploadClass * klass)
{
  GObjectClass *gobject_class;
  GstElementClass *gstelement_class;
  GstBaseTransformClass *gstbasetransform_class;

  gobject_class = (GObjectClass *) klass;
  gstelement_class = (GstElementClass *) klass;
  gstbasetransform_class = (GstBaseTransformClass *) klass;

  gobject_class->set_property = gst_vulkan_upload_set_property;
  gobject_class->get_property = gst_vulkan_upload_get_property;

  gst_element_class_set_static_metadata (gstelement_class, "Vulkan Uploader",
      "Filter/Video", "A Vulkan data uploader",
      "Matthew Waters <matthew@centricular.com>");

  {
    GstCaps *caps;

    caps = _get_input_template_caps ();
    gst_element_class_add_pad_template (gstelement_class,
        gst_pad_template_new ("sink", GST_PAD_SINK, GST_PAD_ALWAYS, caps));
    gst_caps_unref (caps);

    caps = _get_output_template_caps ();
    gst_element_class_add_pad_template (gstelement_class,
        gst_pad_template_new ("src", GST_PAD_SRC, GST_PAD_ALWAYS, caps));
    gst_caps_unref (caps);
  }

  gobject_class->finalize = gst_vulkan_upload_finalize;

  gstelement_class->change_state = gst_vulkan_upload_change_state;
  gstelement_class->set_context = gst_vulkan_upload_set_context;
  gstbasetransform_class->query = GST_DEBUG_FUNCPTR (gst_vulkan_upload_query);
  gstbasetransform_class->set_caps = gst_vulkan_upload_set_caps;
  gstbasetransform_class->transform_caps = gst_vulkan_upload_transform_caps;
  gstbasetransform_class->propose_allocation =
      gst_vulkan_upload_propose_allocation;
  gstbasetransform_class->decide_allocation =
      gst_vulkan_upload_decide_allocation;
  gstbasetransform_class->transform = gst_vulkan_upload_transform;
  gstbasetransform_class->prepare_output_buffer =
      gst_vulkan_upload_prepare_output_buffer;
}

static void
gst_vulkan_upload_init (GstVulkanUpload * vk_upload)
{
  guint i, n;

  n = G_N_ELEMENTS (upload_methods);
  vk_upload->upload_impls = g_malloc (sizeof (gpointer) * n);
  for (i = 0; i < n; i++) {
    vk_upload->upload_impls[i] = upload_methods[i]->new_impl (vk_upload);
  }
}

static void
gst_vulkan_upload_finalize (GObject * object)
{
  GstVulkanUpload *vk_upload = GST_VULKAN_UPLOAD (object);
  guint i;

  gst_caps_replace (&vk_upload->in_caps, NULL);
  gst_caps_replace (&vk_upload->out_caps, NULL);

  for (i = 0; i < G_N_ELEMENTS (upload_methods); i++) {
    upload_methods[i]->free (vk_upload->upload_impls[i]);
  }
  g_free (vk_upload->upload_impls);
  vk_upload->upload_impls = NULL;

  G_OBJECT_CLASS (parent_class)->finalize (object);
}

static void
gst_vulkan_upload_set_property (GObject * object, guint prop_id,
    const GValue * value, GParamSpec * pspec)
{
//  GstVulkanUpload *vk_upload = GST_VULKAN_UPLOAD (object);

  switch (prop_id) {
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
  }
}

static void
gst_vulkan_upload_get_property (GObject * object, guint prop_id,
    GValue * value, GParamSpec * pspec)
{
//  GstVulkanUpload *vk_upload = GST_VULKAN_UPLOAD (object);

  switch (prop_id) {
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
  }
}

static gboolean
gst_vulkan_upload_query (GstBaseTransform * bt, GstPadDirection direction,
    GstQuery * query)
{
  GstVulkanUpload *vk_upload = GST_VULKAN_UPLOAD (bt);

  switch (GST_QUERY_TYPE (query)) {
    case GST_QUERY_CONTEXT:{
      if (gst_vulkan_handle_context_query (GST_ELEMENT (vk_upload), query,
              NULL, vk_upload->instance, vk_upload->device))
        return TRUE;

      if (gst_vulkan_queue_handle_context_query (GST_ELEMENT (vk_upload), query,
              vk_upload->queue))
        return TRUE;

      break;
    }
    default:
      break;
  }

  return GST_BASE_TRANSFORM_CLASS (parent_class)->query (bt, direction, query);
}

static void
gst_vulkan_upload_set_context (GstElement * element, GstContext * context)
{
  GstVulkanUpload *vk_upload = GST_VULKAN_UPLOAD (element);

  gst_vulkan_handle_set_context (element, context, NULL, &vk_upload->instance);

  GST_ELEMENT_CLASS (parent_class)->set_context (element, context);
}

static GstStateChangeReturn
gst_vulkan_upload_change_state (GstElement * element, GstStateChange transition)
{
  GstVulkanUpload *vk_upload = GST_VULKAN_UPLOAD (element);
  GstStateChangeReturn ret = GST_STATE_CHANGE_SUCCESS;

  GST_DEBUG ("changing state: %s => %s",
      gst_state_get_name (GST_STATE_TRANSITION_CURRENT (transition)),
      gst_state_get_name (GST_STATE_TRANSITION_NEXT (transition)));

  switch (transition) {
    case GST_STATE_CHANGE_NULL_TO_READY:
      break;
    case GST_STATE_CHANGE_READY_TO_PAUSED:
      if (!gst_vulkan_ensure_element_data (element, NULL, &vk_upload->instance)) {
        GST_ELEMENT_ERROR (vk_upload, RESOURCE, NOT_FOUND,
            ("Failed to retrieve vulkan instance"), (NULL));
        return GST_STATE_CHANGE_FAILURE;
      }
      if (!gst_vulkan_ensure_element_device (element, vk_upload->instance,
              &vk_upload->device, 0)) {
        return GST_STATE_CHANGE_FAILURE;
      }
      // Issue with NVIDIA driver where the output gets artifacts if I select another
      // queue seen the codec one does not support VK_QUEUE_GRAPHICS_BIT but VK_QUEUE_TRANSFER_BIT.
      if (gst_vulkan_queue_run_context_query (GST_ELEMENT (vk_upload),
              &vk_upload->queue)) {
        guint32 flags, idx;

        GST_DEBUG_OBJECT (vk_upload, "Queue retrieved from peer elements");
        idx = vk_upload->queue->family;
        flags = vk_upload->device->physical_device->queue_family_props[idx]
            .queueFlags;
        if ((flags & (VK_QUEUE_GRAPHICS_BIT | VK_QUEUE_TRANSFER_BIT)) == 0) {
          GST_DEBUG_OBJECT (vk_upload,
              "Queue does not support VK_QUEUE_GRAPHICS_BIT with VK_QUEUE_TRANSFER_BIT");
          gst_clear_object (&vk_upload->queue);
        }
      }

      if (!vk_upload->queue) {
        vk_upload->queue =
            gst_vulkan_device_select_queue (vk_upload->device,
            VK_QUEUE_GRAPHICS_BIT);
      }
      if (!vk_upload->queue) {
        GST_ELEMENT_ERROR (vk_upload, RESOURCE, NOT_FOUND,
            ("Failed to create/retrieve a valid vulkan queue"), (NULL));
        return GST_STATE_CHANGE_FAILURE;
      }
      break;
    case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
      break;
    default:
      break;
  }

  ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
  if (ret == GST_STATE_CHANGE_FAILURE)
    return ret;

  switch (transition) {
    case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
      break;
    case GST_STATE_CHANGE_PAUSED_TO_READY:
      if (vk_upload->queue)
        gst_object_unref (vk_upload->queue);
      vk_upload->queue = NULL;
      if (vk_upload->device)
        gst_object_unref (vk_upload->device);
      vk_upload->device = NULL;
      if (vk_upload->instance)
        gst_object_unref (vk_upload->instance);
      vk_upload->instance = NULL;
      break;
    case GST_STATE_CHANGE_READY_TO_NULL:
      break;
    default:
      break;
  }

  return ret;
}

static GstCaps *
gst_vulkan_upload_transform_caps (GstBaseTransform * bt,
    GstPadDirection direction, GstCaps * caps, GstCaps * filter)
{
  GstVulkanUpload *vk_upload = GST_VULKAN_UPLOAD (bt);
  GstCaps *result, *tmp;
  gint i;

  tmp = gst_caps_new_empty ();

  for (i = 0; i < G_N_ELEMENTS (upload_methods); i++) {
    GstCaps *tmp2;
    GstCaps *templ;

    if (direction == GST_PAD_SINK) {
      templ = gst_static_caps_get (upload_methods[i]->in_template);
    } else {
      templ = gst_static_caps_get (upload_methods[i]->out_template);
    }
    if (!gst_caps_can_intersect (caps, templ)) {
      gst_caps_unref (templ);
      continue;
    }
    gst_caps_unref (templ);

    tmp2 = upload_methods[i]->transform_caps (vk_upload->upload_impls[i],
        direction, caps);

    if (tmp2)
      tmp = gst_caps_merge (tmp, tmp2);
  }

  if (filter) {
    result = gst_caps_intersect_full (filter, tmp, GST_CAPS_INTERSECT_FIRST);
    gst_caps_unref (tmp);
  } else {
    result = tmp;
  }

  return result;
}

static gboolean
gst_vulkan_upload_set_caps (GstBaseTransform * bt, GstCaps * in_caps,
    GstCaps * out_caps)
{
  GstVulkanUpload *vk_upload = GST_VULKAN_UPLOAD (bt);
  gboolean found_method = FALSE;
  guint i;

  gst_caps_replace (&vk_upload->in_caps, in_caps);
  gst_caps_replace (&vk_upload->out_caps, out_caps);

  for (i = 0; i < G_N_ELEMENTS (upload_methods); i++) {
    GstCaps *templ;

    templ = gst_static_caps_get (upload_methods[i]->in_template);
    if (!gst_caps_can_intersect (in_caps, templ)) {
      gst_caps_unref (templ);
      continue;
    }
    gst_caps_unref (templ);

    templ = gst_static_caps_get (upload_methods[i]->out_template);
    if (!gst_caps_can_intersect (out_caps, templ)) {
      gst_caps_unref (templ);
      continue;
    }
    gst_caps_unref (templ);

    if (!upload_methods[i]->set_caps (vk_upload->upload_impls[i], in_caps,
            out_caps))
      continue;

    GST_LOG_OBJECT (bt, "uploader %s accepted caps in: %" GST_PTR_FORMAT
        " out: %" GST_PTR_FORMAT, upload_methods[i]->name, in_caps, out_caps);

    vk_upload->current_impl = i;
    found_method = TRUE;
    break;
  }

  GST_DEBUG_OBJECT (bt,
      "set caps in: %" GST_PTR_FORMAT " out: %" GST_PTR_FORMAT, in_caps,
      out_caps);

  return found_method;
}

static gboolean
gst_vulkan_upload_propose_allocation (GstBaseTransform * bt,
    GstQuery * decide_query, GstQuery * query)
{
  GstVulkanUpload *vk_upload = GST_VULKAN_UPLOAD (bt);
  guint i;

  for (i = 0; i < G_N_ELEMENTS (upload_methods); i++) {
    GstCaps *templ;

    templ = gst_static_caps_get (upload_methods[i]->in_template);
    if (!gst_caps_can_intersect (vk_upload->in_caps, templ)) {
      gst_caps_unref (templ);
      continue;
    }
    gst_caps_unref (templ);

    templ = gst_static_caps_get (upload_methods[i]->out_template);
    if (!gst_caps_can_intersect (vk_upload->out_caps, templ)) {
      gst_caps_unref (templ);
      continue;
    }
    gst_caps_unref (templ);

    upload_methods[i]->propose_allocation (vk_upload->upload_impls[i],
        decide_query, query);
  }

  return TRUE;
}

static GstBufferPool *
gst_vulkan_upload_create_buffer_pool (GstVulkanUpload * vk_upload)
{
  gboolean is_image;
  GstCapsFeatures *feats = gst_caps_get_features (vk_upload->out_caps, 0);

  is_image =
      gst_caps_features_contains (feats, GST_CAPS_FEATURE_MEMORY_VULKAN_IMAGE);

  if (is_image)
    return gst_vulkan_image_buffer_pool_new (vk_upload->device);
  return gst_vulkan_buffer_pool_new (vk_upload->device);
}

static gboolean
gst_vulkan_upload_decide_allocation (GstBaseTransform * bt, GstQuery * query)
{
  GstVulkanUpload *vk_upload = GST_VULKAN_UPLOAD (bt);
  GstBufferPool *pool = NULL;
  GstStructure *config;
  GstCaps *caps;
  guint min, max, size;
  gboolean update_pool, is_vulkan_pool;
  VkImageUsageFlags usage = VK_IMAGE_USAGE_TRANSFER_SRC_BIT
      | VK_IMAGE_USAGE_TRANSFER_DST_BIT | VK_IMAGE_USAGE_SAMPLED_BIT
      | VK_IMAGE_USAGE_STORAGE_BIT;
  VkImageLayout layout = VK_IMAGE_LAYOUT_UNDEFINED;
  VkMemoryPropertyFlags mem_props = VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT;
  guint64 access = 0;           /* VK_ACCESS_NONE */

  gst_query_parse_allocation (query, &caps, NULL);
  if (!caps)
    return FALSE;

  if (gst_query_get_n_allocation_pools (query) > 0) {
    gst_query_parse_nth_allocation_pool (query, 0, &pool, &size, &min, &max);

    update_pool = TRUE;
    is_vulkan_pool = GST_IS_VULKAN_IMAGE_BUFFER_POOL (pool)
        || GST_IS_VULKAN_BUFFER_POOL (pool);
  } else {
    GstVideoInfo vinfo;

    gst_video_info_init (&vinfo);
    gst_video_info_from_caps (&vinfo, caps);

    size = GST_VIDEO_INFO_SIZE (&vinfo);
    min = max = 0;
    is_vulkan_pool = update_pool = FALSE;
  }

  if (!pool || !is_vulkan_pool) {
    if (pool)
      gst_object_unref (pool);
    pool = gst_vulkan_upload_create_buffer_pool (vk_upload);
  }

  config = gst_buffer_pool_get_config (pool);

  if (GST_IS_VULKAN_IMAGE_BUFFER_POOL (pool)) {
    gst_vulkan_image_buffer_pool_config_get_allocation_params (config, &usage,
        &mem_props, &layout, &access);
    /* these usage parameters are essential for upload */
    usage |= VK_IMAGE_USAGE_TRANSFER_SRC_BIT | VK_IMAGE_USAGE_TRANSFER_DST_BIT;
  }

  gst_buffer_pool_config_set_params (config, caps, size, min, max);

  if (GST_IS_VULKAN_IMAGE_BUFFER_POOL (pool)) {
    gst_vulkan_image_buffer_pool_config_set_allocation_params (config, usage,
        mem_props, layout, access);
  }

  if (gst_buffer_pool_has_option (pool, GST_BUFFER_POOL_OPTION_VIDEO_META)) {
    gst_buffer_pool_config_add_option (config,
        GST_BUFFER_POOL_OPTION_VIDEO_META);
  }

  if (!gst_buffer_pool_set_config (pool, config)) {
    GST_ERROR_OBJECT (pool, "Vulkan Image buffer pool doesn't support requested"
        " configuration");
    gst_object_unref (pool);
    return FALSE;
  }

  if (update_pool)
    gst_query_set_nth_allocation_pool (query, 0, pool, size, min, max);
  else
    gst_query_add_allocation_pool (query, pool, size, min, max);

  gst_object_unref (pool);

  return TRUE;
}

static gboolean
_upload_find_method (GstVulkanUpload * vk_upload)
{
  vk_upload->current_impl++;

  if (vk_upload->current_impl >= G_N_ELEMENTS (upload_methods))
    return FALSE;

  GST_DEBUG_OBJECT (vk_upload, "attempting upload with uploader %s",
      upload_methods[vk_upload->current_impl]->name);

  return TRUE;
}

static GstFlowReturn
gst_vulkan_upload_prepare_output_buffer (GstBaseTransform * bt,
    GstBuffer * inbuf, GstBuffer ** outbuf)
{
  GstBaseTransformClass *bclass = GST_BASE_TRANSFORM_GET_CLASS (bt);
  GstVulkanUpload *vk_upload = GST_VULKAN_UPLOAD (bt);
  GstFlowReturn ret;

restart:
  {
    gpointer method_impl;
    const struct UploadMethod *method;

    method = upload_methods[vk_upload->current_impl];
    method_impl = vk_upload->upload_impls[vk_upload->current_impl];

    ret = method->perform (method_impl, inbuf, outbuf);
    if (ret != GST_FLOW_OK) {
    next_method:
      if (!_upload_find_method (vk_upload)) {
        GST_ELEMENT_ERROR (bt, RESOURCE, NOT_FOUND,
            ("Could not find suitable uploader"), (NULL));
        return GST_FLOW_ERROR;
      }

      method = upload_methods[vk_upload->current_impl];
      method_impl = vk_upload->upload_impls[vk_upload->current_impl];
      if (!method->set_caps (method_impl, vk_upload->in_caps,
              vk_upload->out_caps))
        /* try the next method */
        goto next_method;

      /* try the uploading with the next method */
      goto restart;
    }
  }

  if (ret == GST_FLOW_OK) {
    /* basetransform doesn't unref if they're the same */
    if (inbuf != *outbuf)
      bclass->copy_metadata (bt, inbuf, *outbuf);
  }

  return ret;
}

static GstFlowReturn
gst_vulkan_upload_transform (GstBaseTransform * bt, GstBuffer * inbuf,
    GstBuffer * outbuf)
{
  return GST_FLOW_OK;
}
