/*

 * GStreamer

 * Copyright (C) 2012 Matthew Waters <ystree00@gmail.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.

 */

#ifdef HAVE_CONFIG_H

#include "config.h"

#endif

#include <gst/gl/gl.h>

#if GST_GL_HAVE_PLATFORM_EGL && GST_GL_HAVE_DMABUF

#include <gst/gl/egl/gsteglimage.h>

#include <gst/allocators/gstdmabuf.h>

#endif

#include "gstgldownloadelement.h"

GST_DEBUG_CATEGORY_STATIC (gst_gl_download_element_debug);

#define GST_CAT_DEFAULT gst_gl_download_element_debug

#define gst_gl_download_element_parent_class parent_class

G_DEFINE_TYPE_WITH_CODE (GstGLDownloadElement, gst_gl_download_element,

    GST_TYPE_GL_BASE_FILTER,

    GST_DEBUG_CATEGORY_INIT (gst_gl_download_element_debug, "gldownloadelement",

        0, "download element"););

static gboolean gst_gl_download_element_get_unit_size (GstBaseTransform * trans,

    GstCaps * caps, gsize * size);

static GstCaps *gst_gl_download_element_transform_caps (GstBaseTransform * bt,

    GstPadDirection direction, GstCaps * caps, GstCaps * filter);

static gboolean gst_gl_download_element_set_caps (GstBaseTransform * bt,

    GstCaps * in_caps, GstCaps * out_caps);

static GstFlowReturn

gst_gl_download_element_prepare_output_buffer (GstBaseTransform * bt,

    GstBuffer * buffer, GstBuffer ** outbuf);

static GstFlowReturn gst_gl_download_element_transform (GstBaseTransform * bt,

    GstBuffer * buffer, GstBuffer * outbuf);

static gboolean gst_gl_download_element_decide_allocation (GstBaseTransform *

    trans, GstQuery * query);

static void gst_gl_download_element_finalize (GObject * object);

#if GST_GL_HAVE_PLATFORM_EGL && GST_GL_HAVE_DMABUF

#define EXTRA_CAPS_TEMPLATE "video/x-raw(" GST_CAPS_FEATURE_MEMORY_DMABUF "); "

#else

#define EXTRA_CAPS_TEMPLATE

#endif

static GstStaticPadTemplate gst_gl_download_element_src_pad_template =

    GST_STATIC_PAD_TEMPLATE ("src",

    GST_PAD_SRC,

    GST_PAD_ALWAYS,

    GST_STATIC_CAPS (EXTRA_CAPS_TEMPLATE

        "video/x-raw; video/x-raw(memory:GLMemory)"));

static GstStaticPadTemplate gst_gl_download_element_sink_pad_template =

    GST_STATIC_PAD_TEMPLATE ("sink",

    GST_PAD_SINK,

    GST_PAD_ALWAYS,

    GST_STATIC_CAPS ("video/x-raw(memory:GLMemory); video/x-raw"));

static void

gst_gl_download_element_class_init (GstGLDownloadElementClass * klass)

{

  GstBaseTransformClass *bt_class = GST_BASE_TRANSFORM_CLASS (klass);

  GstElementClass *element_class = GST_ELEMENT_CLASS (klass);

  GObjectClass *object_class = G_OBJECT_CLASS (klass);

  bt_class->transform_caps = gst_gl_download_element_transform_caps;

  bt_class->set_caps = gst_gl_download_element_set_caps;

  bt_class->get_unit_size = gst_gl_download_element_get_unit_size;

  bt_class->prepare_output_buffer =

      gst_gl_download_element_prepare_output_buffer;

  bt_class->transform = gst_gl_download_element_transform;

  bt_class->decide_allocation = gst_gl_download_element_decide_allocation;

  bt_class->passthrough_on_same_caps = TRUE;

  gst_element_class_add_static_pad_template (element_class,

      &gst_gl_download_element_src_pad_template);

  gst_element_class_add_static_pad_template (element_class,

      &gst_gl_download_element_sink_pad_template);

  gst_element_class_set_metadata (element_class,

      "OpenGL downloader", "Filter/Video",

      "Downloads data from OpenGL", "Matthew Waters <matthew@centricular.com>");

  object_class->finalize = gst_gl_download_element_finalize;

}

static void

gst_gl_download_element_init (GstGLDownloadElement * download)

{

  gst_base_transform_set_prefer_passthrough (GST_BASE_TRANSFORM (download),

      TRUE);

}

static gboolean

gst_gl_download_element_set_caps (GstBaseTransform * bt, GstCaps * in_caps,

    GstCaps * out_caps)

{

  GstGLDownloadElement *dl = GST_GL_DOWNLOAD_ELEMENT (bt);

  GstVideoInfo out_info;

  GstCapsFeatures *features = NULL;

  if (!gst_video_info_from_caps (&out_info, out_caps))

    return FALSE;

  features = gst_caps_get_features (out_caps, 0);

  dl->do_pbo_transfers = FALSE;

  if (dl->dmabuf_allocator) {

    gst_object_unref (GST_OBJECT (dl->dmabuf_allocator));

    dl->dmabuf_allocator = NULL;

  }

  if (!features) {

    dl->do_pbo_transfers = TRUE;

    return TRUE;

  }

  if (gst_caps_features_contains (features, GST_CAPS_FEATURE_MEMORY_GL_MEMORY)) {

    /* do nothing with the buffer */

#if GST_GL_HAVE_PLATFORM_EGL && GST_GL_HAVE_DMABUF

  } else if (gst_caps_features_contains (features,

          GST_CAPS_FEATURE_MEMORY_DMABUF)) {

    dl->dmabuf_allocator = gst_dmabuf_allocator_new ();

#endif

  } else if (gst_caps_features_contains (features,

          GST_CAPS_FEATURE_MEMORY_SYSTEM_MEMORY)) {

    dl->do_pbo_transfers = TRUE;

  }

  return TRUE;

}

static GstCaps *

_set_caps_features (const GstCaps * caps, const gchar * feature_name)

{

  GstCaps *tmp = gst_caps_copy (caps);

  guint n = gst_caps_get_size (tmp);

  guint i = 0;

  for (i = 0; i < n; i++)

    gst_caps_set_features (tmp, i,

        gst_caps_features_from_string (feature_name));

  return tmp;

}

static void

_remove_field (GstCaps * caps, const gchar * field)

{

  guint n = gst_caps_get_size (caps);

  guint i = 0;

  for (i = 0; i < n; i++) {

    GstStructure *s = gst_caps_get_structure (caps, i);

    gst_structure_remove_field (s, field);

  }

}

static GstCaps *

gst_gl_download_element_transform_caps (GstBaseTransform * bt,

    GstPadDirection direction, GstCaps * caps, GstCaps * filter)

{

  GstCaps *result, *tmp;

  if (direction == GST_PAD_SRC) {

    tmp = _set_caps_features (caps, GST_CAPS_FEATURE_MEMORY_GL_MEMORY);

    tmp = gst_caps_merge (gst_caps_ref (caps), tmp);

  } else {

    GstCaps *newcaps;

    tmp = gst_caps_ref (caps);

#if GST_GL_HAVE_PLATFORM_EGL && GST_GL_HAVE_DMABUF

    newcaps = _set_caps_features (caps, GST_CAPS_FEATURE_MEMORY_DMABUF);

    _remove_field (newcaps, "texture-target");

    tmp = gst_caps_merge (tmp, newcaps);

#endif

    newcaps = _set_caps_features (caps, GST_CAPS_FEATURE_MEMORY_SYSTEM_MEMORY);

    _remove_field (newcaps, "texture-target");

    tmp = gst_caps_merge (tmp, newcaps);

  }

  if (filter) {

    result = gst_caps_intersect_full (filter, tmp, GST_CAPS_INTERSECT_FIRST);

    gst_caps_unref (tmp);

  } else {

    result = tmp;

  }

  GST_DEBUG_OBJECT (bt, "returning caps %" GST_PTR_FORMAT, result);

  return result;

}

static gboolean

gst_gl_download_element_get_unit_size (GstBaseTransform * trans, GstCaps * caps,

    gsize * size)

{

  gboolean ret = FALSE;

  GstVideoInfo info;

  ret = gst_video_info_from_caps (&info, caps);

  if (ret)

    *size = GST_VIDEO_INFO_SIZE (&info;;

  return TRUE;

}

#if GST_GL_HAVE_PLATFORM_EGL && GST_GL_HAVE_DMABUF

struct DmabufInfo

{

  GstMemory *dmabuf;

  gint stride;

  gsize offset;

};

static void

_free_dmabuf_info (struct DmabufInfo *info)

{

  gst_memory_unref (info->dmabuf);

  g_free (info);

}

static GQuark

_dmabuf_info_quark (void)

{

  static GQuark quark = 0;

  if (!quark)

    quark = g_quark_from_static_string ("GstGLDownloadDmabufInfo");

  return quark;

}

static struct DmabufInfo *

_get_cached_dmabuf_info (GstGLMemory * mem)

{

  return gst_mini_object_get_qdata (GST_MINI_OBJECT (mem),

      _dmabuf_info_quark ());

}

static void

_set_cached_dmabuf_info (GstGLMemory * mem, struct DmabufInfo *info)

{

  return gst_mini_object_set_qdata (GST_MINI_OBJECT (mem),

      _dmabuf_info_quark (), info, (GDestroyNotify) _free_dmabuf_info);

}

struct DmabufTransfer

{

  GstGLDownloadElement *download;

  GstGLMemory *glmem;

  struct DmabufInfo *info;

};

static void

_create_cached_dmabuf_info (GstGLContext * context, gpointer data)

{

  struct DmabufTransfer *transfer = (struct DmabufTransfer *) data;

  GstEGLImage *image;

  image = gst_egl_image_from_texture (context, transfer->glmem, NULL);

  if (image) {

    int fd;

    gint stride;

    gsize offset;

    if (gst_egl_image_export_dmabuf (image, &fd, &stride, &offset)) {

      GstGLDownloadElement *download = transfer->download;

      struct DmabufInfo *info;

      gsize maxsize;

      gst_memory_get_sizes (GST_MEMORY_CAST (transfer->glmem), NULL, &maxsize);

      info = g_new0 (struct DmabufInfo, 1);

      info->dmabuf =

          gst_dmabuf_allocator_alloc (download->dmabuf_allocator, fd, maxsize);

      info->stride = stride;

      info->offset = offset;

      transfer->info = info;

    }

    gst_egl_image_unref (image);

  }

}

static GstBuffer *

_try_export_dmabuf (GstGLDownloadElement * download, GstBuffer * inbuf)

{

  GstGLMemory *glmem;

  GstBuffer *buffer = NULL;

  int i;

  gsize offset[GST_VIDEO_MAX_PLANES];

  gint stride[GST_VIDEO_MAX_PLANES];

  GstCaps *src_caps;

  GstVideoInfo out_info;

  gsize total_offset;

  glmem = GST_GL_MEMORY_CAST (gst_buffer_peek_memory (inbuf, 0));

  if (glmem) {

    GstGLContext *context = GST_GL_BASE_MEMORY_CAST (glmem)->context;

    if (gst_gl_context_get_gl_platform (context) != GST_GL_PLATFORM_EGL)

      return NULL;

  }

  buffer = gst_buffer_new ();

  total_offset = 0;

  for (i = 0; i < gst_buffer_n_memory (inbuf); i++) {

    struct DmabufInfo *info;

    glmem = GST_GL_MEMORY_CAST (gst_buffer_peek_memory (inbuf, i));

    info = _get_cached_dmabuf_info (glmem);

    if (!info) {

      GstGLContext *context = GST_GL_BASE_MEMORY_CAST (glmem)->context;

      struct DmabufTransfer transfer;

      transfer.download = download;

      transfer.glmem = glmem;

      transfer.info = NULL;

      gst_gl_context_thread_add (context, _create_cached_dmabuf_info,

          &transfer);

      info = transfer.info;

      if (info)

        _set_cached_dmabuf_info (glmem, info);

    }

    if (info) {

      offset[i] = total_offset + info->offset;

      stride[i] = info->stride;

      total_offset += gst_memory_get_sizes (info->dmabuf, NULL, NULL);

      gst_buffer_insert_memory (buffer, -1, gst_memory_ref (info->dmabuf));

    } else {

      gst_buffer_unref (buffer);

      buffer = NULL;

      goto export_complete;

    }

  }

  src_caps = gst_pad_get_current_caps (GST_BASE_TRANSFORM (download)->srcpad);

  gst_video_info_from_caps (&out_info, src_caps);

  if (download->add_videometa) {

    gst_buffer_add_video_meta_full (buffer, GST_VIDEO_FRAME_FLAG_NONE,

        out_info.finfo->format, out_info.width, out_info.height,

        out_info.finfo->n_planes, offset, stride);

  } else {

    int i;

    gboolean match = TRUE;

    for (i = 0; i < gst_buffer_n_memory (inbuf); i++) {

      if (offset[i] != out_info.offset[i] || stride[i] != out_info.stride[i]) {

        match = FALSE;

        break;

      }

    }

    if (!match) {

      gst_buffer_unref (buffer);

      buffer = NULL;

    }

  }

export_complete:

  return buffer;

}

#endif /* GST_GL_HAVE_PLATFORM_EGL && GST_GL_HAVE_DMABUF */

static GstFlowReturn

gst_gl_download_element_prepare_output_buffer (GstBaseTransform * bt,

    GstBuffer * inbuf, GstBuffer ** outbuf)

{

  GstGLDownloadElement *dl = GST_GL_DOWNLOAD_ELEMENT (bt);

  gint i, n;

  *outbuf = inbuf;

  if (dl->do_pbo_transfers) {

    n = gst_buffer_n_memory (*outbuf);

    for (i = 0; i < n; i++) {

      GstMemory *mem = gst_buffer_peek_memory (*outbuf, i);

      if (gst_is_gl_memory_pbo (mem))

        gst_gl_memory_pbo_download_transfer ((GstGLMemoryPBO *) mem);

    }

  }

#if GST_GL_HAVE_PLATFORM_EGL && GST_GL_HAVE_DMABUF

  else if (dl->dmabuf_allocator) {

    GstBuffer *buffer = _try_export_dmabuf (dl, inbuf);

    if (buffer) {

      if (GST_BASE_TRANSFORM_GET_CLASS (bt)->copy_metadata)

        if (!GST_BASE_TRANSFORM_GET_CLASS (bt)->copy_metadata (bt, inbuf,

                buffer)) {

          GST_ELEMENT_WARNING (GST_ELEMENT (bt), STREAM, NOT_IMPLEMENTED,

              ("could not copy metadata"), (NULL));

        }

      *outbuf = buffer;

    } else {

      GstCaps *src_caps;

      GstCapsFeatures *features;

      gst_object_unref (dl->dmabuf_allocator);

      dl->dmabuf_allocator = NULL;

      src_caps = gst_pad_get_current_caps (bt->srcpad);

      src_caps = gst_caps_make_writable (src_caps);

      features = gst_caps_get_features (src_caps, 0);

      gst_caps_features_remove (features, GST_CAPS_FEATURE_MEMORY_DMABUF);

      if (!gst_base_transform_update_src_caps (bt, src_caps)) {

        GST_ERROR_OBJECT (bt, "DMABuf exportation didn't work and system "

            "memory is not supported.");

        return GST_FLOW_NOT_NEGOTIATED;

      }

    }

  }

#endif

  return GST_FLOW_OK;

}

static GstFlowReturn

gst_gl_download_element_transform (GstBaseTransform * bt,

    GstBuffer * inbuf, GstBuffer * outbuf)

{

  return GST_FLOW_OK;

}

static gboolean

gst_gl_download_element_decide_allocation (GstBaseTransform * trans,

    GstQuery * query)

{

  GstGLDownloadElement *download = GST_GL_DOWNLOAD_ELEMENT_CAST (trans);

  if (gst_query_find_allocation_meta (query, GST_VIDEO_META_API_TYPE, NULL)) {

    download->add_videometa = TRUE;

  } else {

    download->add_videometa = FALSE;

  }

  return GST_BASE_TRANSFORM_CLASS (parent_class)->decide_allocation (trans,

      query);

}

static void

gst_gl_download_element_finalize (GObject * object)

{

  GstGLDownloadElement *download = GST_GL_DOWNLOAD_ELEMENT_CAST (object);

  if (download->dmabuf_allocator) {

    gst_object_unref (GST_OBJECT (download->dmabuf_allocator));

    download->dmabuf_allocator = NULL;

  }

  G_OBJECT_CLASS (parent_class)->finalize (object);

}