/*
 * GStreamer
 * Copyright (C) 2007 David Schleef <ds@schleef.org>
 * Copyright (C) 2008 Julien Isorce <julien.isorce@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., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */

/**
 * SECTION:element-glupload
 *
 * upload video frames video frames into opengl textures.
 *
 * <refsect2>
 * <title>Color space conversion</title>
 * <para>
 * Depends on the driver and when needed, the color space conversion is made
 * in a fragment shader using one frame buffer object instance, or using
 * mesa ycbcr .
 * </para>
 * </refsect2>
 * <refsect2>
 * <title>Examples</title>
 * |[
 * gst-launch -v videotestsrc ! "video/x-raw-rgb" ! glupload ! glimagesink
 * ]| A pipeline to test hardware scaling.
 * No special opengl extension is used in this pipeline, that's why it should work
 * with OpenGL >= 1.1. That's the case if you are using the MESA3D driver v1.3.
 * |[
 * gst-launch -v videotestsrc ! "video/x-raw-yuv, format=(fourcc)I420" ! glupload ! glimagesink
 * ]| A pipeline to test hardware scaling and hardware colorspace conversion.
 * When your driver supports GLSL (OpenGL Shading Language needs OpenGL >= 2.1),
 * the 4 following format YUY2, UYVY, I420, YV12 and AYUV are converted to RGB32
 * through some fragment shaders and using one framebuffer (FBO extension OpenGL >= 1.4).
 * If your driver does not support GLSL but supports MESA_YCbCr extension then
 * the you can use YUY2 and UYVY. In this case the colorspace conversion is automatically
 * made when loading the texture and therefore no framebuffer is used.
 * |[
 * gst-launch -v videotestsrc ! "video/x-raw-rgb, width=320, height=240" ! glupload ! \
 *    "video/x-raw-gl, width=640, height=480" ! glimagesink
 * ]| A pipeline to test hardware scaling.
 * Frame buffer extension is required. Inded one FBO is used bettween glupload and glimagesink,
 * because the texture needs to be resized.
 * |[
 * gst-launch -v videotestsrc ! "video/x-raw-yuv, width=320, height=240" ! glupload ! \
 *    "video/x-raw-gl, width=640, height=480" ! glimagesink
 * ]| A pipeline to test hardware scaling.
 * Frame buffer extension is required. Inded one FBO is used bettween glupload and glimagesink,
 * because the texture needs to be resized. Depends on your driver the color space conversion
 * is made in a fragment shader using one frame buffer object instance, or using mesa ycbcr .
 * </refsect2>
 */

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

#include "gstglupload.h"


#define GST_CAT_DEFAULT gst_gl_upload_debug
GST_DEBUG_CATEGORY_STATIC (GST_CAT_DEFAULT);

/* Source pad definition */
static GstStaticPadTemplate gst_gl_upload_src_pad_template =
GST_STATIC_PAD_TEMPLATE ("src",
    GST_PAD_SRC,
    GST_PAD_ALWAYS,
    GST_STATIC_CAPS (GST_GL_VIDEO_CAPS)
    );

/* Sink pad definition */
static GstStaticPadTemplate gst_gl_upload_sink_pad_template =
GST_STATIC_PAD_TEMPLATE ("sink",
    GST_PAD_SINK,
    GST_PAD_ALWAYS,
    GST_STATIC_CAPS (GST_GL_UPLOAD_VIDEO_CAPS)
    );

#define DEFAULT_WIDTH 320
#define DEFAULT_HEIGHT 240
#define DEFAULT_FORMAT "RGBA"

/* Properties */
enum
{
  PROP_0,
  PROP_EXTERNAL_OPENGL_CONTEXT
};

#define DEBUG_INIT \
  GST_DEBUG_CATEGORY_INIT (gst_gl_upload_debug, "glupload", 0, "glupload element");

G_DEFINE_TYPE_WITH_CODE (GstGLUpload, gst_gl_upload, GST_TYPE_BASE_TRANSFORM,
    DEBUG_INIT);

static void gst_gl_upload_set_property (GObject * object, guint prop_id,
    const GValue * value, GParamSpec * pspec);
static void gst_gl_upload_get_property (GObject * object, guint prop_id,
    GValue * value, GParamSpec * pspec);

static gboolean gst_gl_upload_src_query (GstPad * pad, GstObject * object,
    GstQuery * query);

static void gst_gl_upload_reset (GstGLUpload * upload);
static gboolean gst_gl_upload_set_caps (GstBaseTransform * bt,
    GstCaps * incaps, GstCaps * outcaps);
static GstCaps *gst_gl_upload_transform_caps (GstBaseTransform * bt,
    GstPadDirection direction, GstCaps * caps, GstCaps * filter);
static GstCaps *gst_gl_upload_fixate_caps (GstBaseTransform * base,
    GstPadDirection direction, GstCaps * caps, GstCaps * othercaps);
static gboolean gst_gl_upload_start (GstBaseTransform * bt);
static gboolean gst_gl_upload_stop (GstBaseTransform * bt);
static GstFlowReturn gst_gl_upload_transform (GstBaseTransform * trans,
    GstBuffer * inbuf, GstBuffer * outbuf);
static gboolean gst_gl_upload_get_unit_size (GstBaseTransform * trans,
    GstCaps * caps, gsize * size);
static gboolean gst_gl_upload_decide_allocation (GstBaseTransform * trans,
    GstQuery * query);
static gboolean gst_gl_upload_propose_allocation (GstBaseTransform * trans,
    GstQuery * decide_allocation, GstQuery * query);

static void
gst_gl_upload_class_init (GstGLUploadClass * klass)
{
  GObjectClass *gobject_class;
  GstElementClass *element_class;

  gobject_class = (GObjectClass *) klass;
  element_class = GST_ELEMENT_CLASS (klass);

  gobject_class->set_property = gst_gl_upload_set_property;
  gobject_class->get_property = gst_gl_upload_get_property;

  GST_BASE_TRANSFORM_CLASS (klass)->transform_caps =
      gst_gl_upload_transform_caps;
  GST_BASE_TRANSFORM_CLASS (klass)->fixate_caps = gst_gl_upload_fixate_caps;
  GST_BASE_TRANSFORM_CLASS (klass)->transform = gst_gl_upload_transform;
  GST_BASE_TRANSFORM_CLASS (klass)->start = gst_gl_upload_start;
  GST_BASE_TRANSFORM_CLASS (klass)->stop = gst_gl_upload_stop;
  GST_BASE_TRANSFORM_CLASS (klass)->set_caps = gst_gl_upload_set_caps;
  GST_BASE_TRANSFORM_CLASS (klass)->get_unit_size = gst_gl_upload_get_unit_size;
  GST_BASE_TRANSFORM_CLASS (klass)->decide_allocation =
      gst_gl_upload_decide_allocation;
  GST_BASE_TRANSFORM_CLASS (klass)->propose_allocation =
      gst_gl_upload_propose_allocation;

  g_object_class_install_property (gobject_class, PROP_EXTERNAL_OPENGL_CONTEXT,
      g_param_spec_ulong ("external-opengl-context",
          "External OpenGL context",
          "Give an external OpenGL context with which to share textures",
          0, G_MAXULONG, 0, G_PARAM_WRITABLE | G_PARAM_STATIC_STRINGS));

  gst_element_class_set_details_simple (element_class, "OpenGL upload",
      "Filter/Effect", "A from video to GL flow filter",
      "Julien Isorce <julien.isorce@gmail.com>");

  gst_element_class_add_pad_template (element_class,
      gst_static_pad_template_get (&gst_gl_upload_src_pad_template));
  gst_element_class_add_pad_template (element_class,
      gst_static_pad_template_get (&gst_gl_upload_sink_pad_template));
}

static void
gst_gl_upload_init (GstGLUpload * upload)
{
  GstBaseTransform *base_trans = GST_BASE_TRANSFORM (upload);

  gst_pad_set_query_function (base_trans->srcpad,
      GST_DEBUG_FUNCPTR (gst_gl_upload_src_query));

  gst_gl_upload_reset (upload);
}

static void
gst_gl_upload_set_property (GObject * object, guint prop_id,
    const GValue * value, GParamSpec * pspec)
{
  GstGLUpload *upload = GST_GL_UPLOAD (object);

  switch (prop_id) {
    case PROP_EXTERNAL_OPENGL_CONTEXT:
    {
      upload->external_gl_context = g_value_get_ulong (value);
      break;
    }
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
  }
}

static void
gst_gl_upload_get_property (GObject * object, guint prop_id,
    GValue * value, GParamSpec * pspec)
{
  //GstGLUpload *upload = GST_GL_UPLOAD (object);

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

static gboolean
gst_gl_upload_src_query (GstPad * pad, GstObject * object, GstQuery * query)
{
  gboolean res;

  switch (GST_QUERY_TYPE (query)) {
    case GST_QUERY_CUSTOM:
    {
      const GstStructure *structure = gst_query_get_structure (query);
      gchar *name = gst_element_get_name (object);
      res = g_strcmp0 (name, gst_structure_get_name (structure)) == 0;
      g_free (name);
      if (!res)
        res = gst_pad_query_default (pad, object, query);
      break;
    }
    default:
      res = gst_pad_query_default (pad, object, query);
      break;
  }

  return res;
}

static void
gst_gl_upload_reset (GstGLUpload * upload)
{
  if (upload->display) {
    g_object_unref (upload->display);
    upload->display = NULL;
  }
  upload->external_gl_context = 0;
}

static gboolean
gst_gl_upload_start (GstBaseTransform * bt)
{
  GstGLUpload *upload = GST_GL_UPLOAD (bt);
  GstStructure *structure;
  GstQuery *display_query;
  const GValue *id_value;

  structure = gst_structure_new_empty ("gstgldisplay");
  display_query = gst_query_new_custom (GST_QUERY_CUSTOM, structure);

  if (!gst_pad_peer_query (bt->srcpad, display_query)) {
    GST_WARNING ("Could not query GstGLDisplay from downstream");
    return FALSE;
  }

  id_value = gst_structure_get_value (structure, "gstgldisplay");
  if (G_VALUE_HOLDS_POINTER (id_value))
    /* at least one gl element is after in our gl chain */
    upload->display =
        g_object_ref (GST_GL_DISPLAY (g_value_get_pointer (id_value)));
  else {
    GST_WARNING ("Incorrect GstGLDisplay from downstream");
    return FALSE;
  }

  return TRUE;
}

static gboolean
gst_gl_upload_stop (GstBaseTransform * bt)
{
  GstGLUpload *upload = GST_GL_UPLOAD (bt);

  gst_gl_upload_reset (upload);

  return TRUE;
}

/* from videoconvert code */
/* copies the given caps */
static GstCaps *
gst_gl_upload_caps_remove_format_info (GstCaps * caps)
{
  GstStructure *st;
  gint i, n;
  GstCaps *res;

  res = gst_caps_new_empty ();

  n = gst_caps_get_size (caps);
  for (i = 0; i < n; i++) {
    st = gst_caps_get_structure (caps, i);

    /* If this is already expressed by the existing caps
     * skip this structure */
    if (i > 0 && gst_caps_is_subset_structure (res, st))
      continue;

    st = gst_structure_copy (st);
    gst_structure_set (st, "width", GST_TYPE_INT_RANGE, 1, G_MAXINT, NULL);
    gst_structure_set (st, "height", GST_TYPE_INT_RANGE, 1, G_MAXINT, NULL);
    gst_structure_remove_fields (st, "format", "palette_data",
        "colorimetry", "chroma-site", NULL);
    gst_caps_append_structure (res, st);
  }

  return res;
}

static GstCaps *
gst_gl_upload_transform_caps (GstBaseTransform * bt,
    GstPadDirection direction, GstCaps * caps, GstCaps * filter)
{
  GstCaps *tmp, *tmp2;
  GstCaps *result;

  /* Get all possible caps that we can transform to */
  tmp = gst_gl_upload_caps_remove_format_info (caps);

  GST_DEBUG_OBJECT (bt, "intersecting %" GST_PTR_FORMAT " with %"
      GST_PTR_FORMAT, filter, tmp);

  if (filter) {
    tmp2 = gst_caps_intersect_full (filter, tmp, GST_CAPS_INTERSECT_FIRST);
    gst_caps_unref (tmp);
    tmp = tmp2;
  }

  result = tmp;

  GST_DEBUG_OBJECT (bt, "transformed %" GST_PTR_FORMAT " into %"
      GST_PTR_FORMAT, caps, result);

  return result;
}

/* from gst-plugins-base "videoscale" code */
static GstCaps *
gst_gl_upload_fixate_caps (GstBaseTransform * base, GstPadDirection direction,
    GstCaps * caps, GstCaps * othercaps)
{
  GstStructure *outs;

  othercaps = gst_caps_truncate (othercaps);
  othercaps = gst_caps_make_writable (othercaps);

  GST_DEBUG_OBJECT (base, "trying to fixate othercaps %" GST_PTR_FORMAT
      " based on caps %" GST_PTR_FORMAT, othercaps, caps);

  outs = gst_caps_get_structure (othercaps, 0);

  gst_structure_fixate_field_nearest_int (outs, "width", DEFAULT_WIDTH);
  gst_structure_fixate_field_nearest_int (outs, "height", DEFAULT_HEIGHT);
  gst_structure_fixate_field_string (outs, "format", DEFAULT_FORMAT);

  GST_DEBUG_OBJECT (base, "fixated othercaps to %" GST_PTR_FORMAT, othercaps);

  return othercaps;
}

static gboolean
gst_gl_upload_set_caps (GstBaseTransform * bt, GstCaps * incaps,
    GstCaps * outcaps)
{
  GstGLUpload *upload;
  gboolean ret;
  GstVideoInfo in_vinfo, out_vinfo;

  GST_DEBUG ("called with %" GST_PTR_FORMAT, incaps);

  upload = GST_GL_UPLOAD (bt);

  ret = gst_video_info_from_caps (&in_vinfo, incaps);
  ret |= gst_video_info_from_caps (&out_vinfo, outcaps);

  if (!ret) {
    GST_DEBUG ("caps connot be parsed");
    return FALSE;
  }

  upload->in_info = in_vinfo;
  upload->out_info = out_vinfo;

  //init colorspace conversion if needed
  if (!gst_gl_display_init_upload (upload->display,
          GST_VIDEO_INFO_FORMAT (&upload->in_info),
          GST_VIDEO_INFO_WIDTH (&upload->out_info),
          GST_VIDEO_INFO_HEIGHT (&upload->out_info),
          GST_VIDEO_INFO_WIDTH (&upload->in_info),
          GST_VIDEO_INFO_HEIGHT (&upload->in_info)))
    goto display_error;

  return TRUE;

/* ERRORS */
display_error:
  {
    GST_ELEMENT_ERROR (upload, RESOURCE, NOT_FOUND,
        GST_GL_DISPLAY_ERR_MSG (upload->display), (NULL));
    return FALSE;
  }
}

static gboolean
gst_gl_upload_get_unit_size (GstBaseTransform * trans, GstCaps * caps,
    gsize * size)
{
  gboolean ret;
  GstVideoInfo vinfo;

  ret = gst_video_info_from_caps (&vinfo, caps);
  if (ret)
    *size = GST_VIDEO_INFO_SIZE (&vinfo);

  return TRUE;
}

static GstFlowReturn
gst_gl_upload_transform (GstBaseTransform * trans, GstBuffer * inbuf,
    GstBuffer * outbuf)
{
  GstGLUpload *upload = GST_GL_UPLOAD (trans);
  GstVideoMeta *smeta, *dmeta;
  GstGLMeta *gl_meta;
  GstVideoFrame frame;

  smeta = gst_buffer_get_video_meta (inbuf);
  dmeta = gst_buffer_get_video_meta (outbuf);
  gl_meta = gst_buffer_get_gl_meta (outbuf);

  if (!smeta) {
    GST_ERROR ("Input buffer does not have required GstVideoMeta");
    goto error;
  }
  if (!dmeta || !gl_meta) {
    GST_ERROR
        ("Output buffer does not have required GstVideoMeta or GstGLMeta");
    goto error;
  }

  if (!gst_video_frame_map (&frame, &upload->in_info, inbuf, GST_MAP_READ)) {
    GST_WARNING ("Could not map data for reading");
    goto error;
  }

  if (!gst_gl_display_do_upload (upload->display, gl_meta->memory->tex_id,
          &frame)) {
    GST_WARNING ("Failed to upload data");
  }

  gst_video_frame_unmap (&frame);

  return GST_FLOW_OK;

/* ERRORS */
error:
  {
    return GST_FLOW_ERROR;
  }
}

static gboolean
gst_gl_upload_decide_allocation (GstBaseTransform * trans, GstQuery * query)
{
  GstGLUpload *upload = GST_GL_UPLOAD (trans);
  GstBufferPool *pool = NULL;
  GstStructure *config;
  GstCaps *caps;
  guint min, max, size;
  gboolean update_pool;

  gst_query_parse_allocation (query, &caps, NULL);

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

    update_pool = TRUE;
  } else {
    GstVideoInfo vinfo;

    gst_video_info_init (&vinfo);
    gst_video_info_from_caps (&vinfo, caps);
    size = vinfo.size;
    min = max = 0;
    update_pool = FALSE;
  }

  if (!pool)
    pool = gst_gl_buffer_pool_new (upload->display);

  config = gst_buffer_pool_get_config (pool);
  gst_buffer_pool_config_set_params (config, caps, size, min, max);
  gst_buffer_pool_config_add_option (config, GST_BUFFER_POOL_OPTION_VIDEO_META);
  gst_buffer_pool_config_add_option (config, GST_BUFFER_POOL_OPTION_GL_META);
  gst_buffer_pool_set_config (pool, config);

  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
gst_gl_upload_propose_allocation (GstBaseTransform * trans,
    GstQuery * decide_query, GstQuery * query)
{
  GstGLUpload *upload = GST_GL_UPLOAD (trans);
  GstBufferPool *pool;
  GstStructure *config;
  GstCaps *caps;
  guint size;
  gboolean need_pool;

  gst_query_parse_allocation (query, &caps, &need_pool);

  if (caps == NULL)
    goto no_caps;

  if ((pool = upload->pool))
    gst_object_ref (pool);

  if (pool != NULL) {
    GstCaps *pcaps;

    /* we had a pool, check caps */
    GST_DEBUG_OBJECT (upload, "check existing pool caps");
    config = gst_buffer_pool_get_config (pool);
    gst_buffer_pool_config_get_params (config, &pcaps, &size, NULL, NULL);

    if (!gst_caps_is_equal (caps, pcaps)) {
      GST_DEBUG_OBJECT (upload, "pool has different caps");
      /* different caps, we can't use this pool */
      gst_object_unref (pool);
      pool = NULL;
    }
    gst_structure_free (config);
  }
  if (pool == NULL && need_pool) {
    GstVideoInfo info;

    if (!gst_video_info_from_caps (&info, caps))
      goto invalid_caps;

    GST_DEBUG_OBJECT (upload, "create new pool");
    pool = gst_video_buffer_pool_new ();

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

    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))
      goto config_failed;
  }
  /* we need at least 2 buffer because we hold on to the last one */
  gst_query_add_allocation_pool (query, pool, size, 2, 0);

  /* we also support various metadata */
  gst_query_add_allocation_meta (query, GST_VIDEO_META_API_TYPE, 0);
  //gst_query_add_allocation_meta (query, GST_VIDEO_CROP_META_API_TYPE);
  gst_query_add_allocation_meta (query, GST_GL_META_API_TYPE, 0);

  gst_object_unref (pool);

  return TRUE;

  /* ERRORS */
no_caps:
  {
    GST_DEBUG_OBJECT (trans, "no caps specified");
    return FALSE;
  }
invalid_caps:
  {
    GST_DEBUG_OBJECT (trans, "invalid caps specified");
    return FALSE;
  }
config_failed:
  {
    GST_DEBUG_OBJECT (trans, "failed setting config");
    return FALSE;
  }
}