/*
 * GStreamer
 * 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-glcolorscale
 *
 * video frame scaling and colorspace conversion.
 *
 * <refsect2>
 * <title>Scaling and Color space conversion</title>
 * <para>
 * Equivalent to glupload ! gldownload.
 * </para>
 * </refsect2>
 * <refsect2>
 * <title>Examples</title>
 * |[
 * gst-launch -v videotestsrc ! "video/x-raw-yuv" ! glcolorscale ! ximagesink
 * ]| A pipeline to test colorspace conversion.
 * FBO is required.
  |[
 * gst-launch -v videotestsrc ! "video/x-raw-yuv, width=640, height=480, format=(fourcc)AYUV" ! glcolorscale ! \
 *   "video/x-raw-yuv, width=320, height=240, format=(fourcc)YV12" ! autovideosink
 * ]| A pipeline to test hardware scaling and colorspace conversion.
 * FBO and GLSL are required.
 * </refsect2>
 */

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

#include "gstglcolorscale.h"


#define GST_CAT_DEFAULT gst_gl_colorscale_debug
GST_DEBUG_CATEGORY_STATIC (GST_CAT_DEFAULT);

/* Source pad definition */
static GstStaticPadTemplate gst_gl_colorscale_src_pad_template =
    GST_STATIC_PAD_TEMPLATE ("src",
    GST_PAD_SRC,
    GST_PAD_ALWAYS,
    GST_STATIC_CAPS (GST_VIDEO_CAPS_RGBx ";"
        GST_VIDEO_CAPS_BGRx ";"
        GST_VIDEO_CAPS_xRGB ";"
        GST_VIDEO_CAPS_xBGR ";"
        GST_VIDEO_CAPS_YUV ("{ I420, YV12, YUY2, UYVY, AYUV }"))
    );

/* Source pad definition */
static GstStaticPadTemplate gst_gl_colorscale_sink_pad_template =
    GST_STATIC_PAD_TEMPLATE ("sink",
    GST_PAD_SINK,
    GST_PAD_ALWAYS,
    GST_STATIC_CAPS (GST_VIDEO_CAPS_RGBx ";"
        GST_VIDEO_CAPS_BGRx ";"
        GST_VIDEO_CAPS_xRGB ";"
        GST_VIDEO_CAPS_xBGR ";"
        GST_VIDEO_CAPS_YUV ("{ I420, YV12, YUY2, UYVY, AYUV }"))
    );

/* Properties */
enum
{
  PROP_0
};

#define DEBUG_INIT(bla) \
  GST_DEBUG_CATEGORY_INIT (gst_gl_colorscale_debug, "glcolorscale", 0, "glcolorscale element");

GST_BOILERPLATE_FULL (GstGLColorscale, gst_gl_colorscale, GstBaseTransform,
    GST_TYPE_BASE_TRANSFORM, DEBUG_INIT);

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

static void gst_gl_colorscale_reset (GstGLColorscale * colorscale);
static gboolean gst_gl_colorscale_set_caps (GstBaseTransform * bt,
    GstCaps * incaps, GstCaps * outcaps);
static GstCaps *gst_gl_colorscale_transform_caps (GstBaseTransform * bt,
    GstPadDirection direction, GstCaps * caps);
static void gst_gl_colorscale_fixate_caps (GstBaseTransform * base,
    GstPadDirection direction, GstCaps * caps, GstCaps * othercaps);
static gboolean gst_gl_colorscale_start (GstBaseTransform * bt);
static gboolean gst_gl_colorscale_stop (GstBaseTransform * bt);
static GstFlowReturn gst_gl_colorscale_transform (GstBaseTransform * trans,
    GstBuffer * inbuf, GstBuffer * outbuf);
static gboolean gst_gl_colorscale_get_unit_size (GstBaseTransform * trans,
    GstCaps * caps, guint * size);


static void
gst_gl_colorscale_base_init (gpointer klass)
{
  GstElementClass *element_class = GST_ELEMENT_CLASS (klass);

  gst_element_class_set_details_simple (element_class, "OpenGL color scale",
      "Filter/Effect", "Colorspace converter and video scaler",
      "Julien Isorce <julien.isorce@gmail.com>");

  gst_element_class_add_pad_template (element_class,
      gst_static_pad_template_get (&gst_gl_colorscale_src_pad_template));
  gst_element_class_add_pad_template (element_class,
      gst_static_pad_template_get (&gst_gl_colorscale_sink_pad_template));
}

static void
gst_gl_colorscale_class_init (GstGLColorscaleClass * klass)
{
  GObjectClass *gobject_class;

  gobject_class = (GObjectClass *) klass;
  gobject_class->set_property = gst_gl_colorscale_set_property;
  gobject_class->get_property = gst_gl_colorscale_get_property;

  GST_BASE_TRANSFORM_CLASS (klass)->transform_caps =
      gst_gl_colorscale_transform_caps;
  GST_BASE_TRANSFORM_CLASS (klass)->fixate_caps = gst_gl_colorscale_fixate_caps;
  GST_BASE_TRANSFORM_CLASS (klass)->transform = gst_gl_colorscale_transform;
  GST_BASE_TRANSFORM_CLASS (klass)->start = gst_gl_colorscale_start;
  GST_BASE_TRANSFORM_CLASS (klass)->stop = gst_gl_colorscale_stop;
  GST_BASE_TRANSFORM_CLASS (klass)->set_caps = gst_gl_colorscale_set_caps;
  GST_BASE_TRANSFORM_CLASS (klass)->get_unit_size =
      gst_gl_colorscale_get_unit_size;
}

static void
gst_gl_colorscale_init (GstGLColorscale * colorscale,
    GstGLColorscaleClass * klass)
{
  gst_gl_colorscale_reset (colorscale);
}

static void
gst_gl_colorscale_set_property (GObject * object, guint prop_id,
    const GValue * value, GParamSpec * pspec)
{
  //GstGLColorscale* colorscale = GST_GL_COLORSCALE (object);

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

static void
gst_gl_colorscale_get_property (GObject * object, guint prop_id,
    GValue * value, GParamSpec * pspec)
{
  //GstGLColorscale *colorscale = GST_GL_COLORSCALE (object);

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

static void
gst_gl_colorscale_reset (GstGLColorscale * colorscale)
{
  if (colorscale->display) {
    g_object_unref (colorscale->display);
    colorscale->display = NULL;
  }
}

static gboolean
gst_gl_colorscale_start (GstBaseTransform * bt)
{
  //GstGLColorscale* colorscale = GST_GL_COLORSCALE (bt);

  return TRUE;
}

static gboolean
gst_gl_colorscale_stop (GstBaseTransform * bt)
{
  GstGLColorscale *colorscale = GST_GL_COLORSCALE (bt);

  gst_gl_colorscale_reset (colorscale);

  return TRUE;
}

static GstCaps *
gst_gl_colorscale_transform_caps (GstBaseTransform * bt,
    GstPadDirection direction, GstCaps * caps)
{
  //GstGLColorscale* colorscale = GST_GL_COLORSCALE (bt);
  GstStructure *structure = gst_caps_get_structure (caps, 0);
  GstCaps *newcaps = gst_caps_new_simple ("video/x-raw-yuv", NULL);
  GstCaps *newothercaps = gst_caps_new_simple ("video/x-raw-rgb", NULL);
  const GValue *framerate_value = NULL;
  const GValue *par_value = NULL;

  GST_DEBUG ("transform caps %" GST_PTR_FORMAT, caps);

  framerate_value = gst_structure_get_value (structure, "framerate");
  par_value = gst_structure_get_value (structure, "pixel-aspect-ratio");

  gst_caps_append (newcaps, newothercaps);


  structure = gst_structure_copy (gst_caps_get_structure (newcaps, 0));

  gst_structure_set (structure,
      "width", GST_TYPE_INT_RANGE, 1, G_MAXINT,
      "height", GST_TYPE_INT_RANGE, 1, G_MAXINT, NULL);

  gst_structure_set_value (structure, "framerate", framerate_value);
  if (par_value)
    gst_structure_set_value (structure, "pixel-aspect-ratio", par_value);
  else
    gst_structure_set (structure, "pixel-aspect-ratio", GST_TYPE_FRACTION,
        1, 1, NULL);

  gst_caps_merge_structure (newcaps, gst_structure_copy (structure));

  GST_DEBUG ("new caps %" GST_PTR_FORMAT, newcaps);

  return newcaps;
}

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

  const GValue *from_par, *to_par;

  g_return_if_fail (gst_caps_is_fixed (caps));

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

  ins = gst_caps_get_structure (caps, 0);
  outs = gst_caps_get_structure (othercaps, 0);

  from_par = gst_structure_get_value (ins, "pixel-aspect-ratio");
  to_par = gst_structure_get_value (outs, "pixel-aspect-ratio");

  //we have both PAR but they might not be fixated
  if (from_par && to_par) {
    gint from_w, from_h, from_par_n, from_par_d, to_par_n, to_par_d;

    gint count = 0, w = 0, h = 0;

    guint num, den;

    //from_par should be fixed
    g_return_if_fail (gst_value_is_fixed (from_par));

    from_par_n = gst_value_get_fraction_numerator (from_par);
    from_par_d = gst_value_get_fraction_denominator (from_par);

    //fixate the out PAR
    if (!gst_value_is_fixed (to_par)) {
      GST_DEBUG_OBJECT (base, "fixating to_par to %dx%d", from_par_n,
          from_par_d);
      gst_structure_fixate_field_nearest_fraction (outs, "pixel-aspect-ratio",
          from_par_n, from_par_d);
    }

    to_par_n = gst_value_get_fraction_numerator (to_par);
    to_par_d = gst_value_get_fraction_denominator (to_par);

    //f both width and height are already fixed, we can't do anything
    //about it anymore
    if (gst_structure_get_int (outs, "width", &w))
      ++count;
    if (gst_structure_get_int (outs, "height", &h))
      ++count;
    if (count == 2) {
      GST_DEBUG_OBJECT (base, "dimensions already set to %dx%d, not fixating",
          w, h);
      return;
    }

    gst_structure_get_int (ins, "width", &from_w);
    gst_structure_get_int (ins, "height", &from_h);

    if (!gst_video_calculate_display_ratio (&num, &den, from_w, from_h,
            from_par_n, from_par_d, to_par_n, to_par_d)) {
      GST_ELEMENT_ERROR (base, CORE, NEGOTIATION, (NULL),
          ("Error calculating the output scaled size - integer overflow"));
      return;
    }

    GST_DEBUG_OBJECT (base,
        "scaling input with %dx%d and PAR %d/%d to output PAR %d/%d",
        from_w, from_h, from_par_n, from_par_d, to_par_n, to_par_d);
    GST_DEBUG_OBJECT (base, "resulting output should respect ratio of %d/%d",
        num, den);

    //now find a width x height that respects this display ratio.
    //prefer those that have one of w/h the same as the incoming video
    //using wd / hd = num / den

    //if one of the output width or height is fixed, we work from there
    if (h) {
      GST_DEBUG_OBJECT (base, "height is fixed,scaling width");
      w = (guint) gst_util_uint64_scale_int (h, num, den);
    } else if (w) {
      GST_DEBUG_OBJECT (base, "width is fixed, scaling height");
      h = (guint) gst_util_uint64_scale_int (w, den, num);
    } else {
      //none of width or height is fixed, figure out both of them based only on
      //the input width and height
      //check hd / den is an integer scale factor, and scale wd with the PAR
      if (from_h % den == 0) {
        GST_DEBUG_OBJECT (base, "keeping video height");
        h = from_h;
        w = (guint) gst_util_uint64_scale_int (h, num, den);
      } else if (from_w % num == 0) {
        GST_DEBUG_OBJECT (base, "keeping video width");
        w = from_w;
        h = (guint) gst_util_uint64_scale_int (w, den, num);
      } else {
        GST_DEBUG_OBJECT (base, "approximating but keeping video height");
        h = from_h;
        w = (guint) gst_util_uint64_scale_int (h, num, den);
      }
    }
    GST_DEBUG_OBJECT (base, "scaling to %dx%d", w, h);

    //now fixate
    gst_structure_fixate_field_nearest_int (outs, "width", w);
    gst_structure_fixate_field_nearest_int (outs, "height", h);
  } else {
    gint width, height;

    if (gst_structure_get_int (ins, "width", &width)) {
      if (gst_structure_has_field (outs, "width"))
        gst_structure_fixate_field_nearest_int (outs, "width", width);
    }
    if (gst_structure_get_int (ins, "height", &height)) {
      if (gst_structure_has_field (outs, "height")) {
        gst_structure_fixate_field_nearest_int (outs, "height", height);
      }
    }
  }

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

static gboolean
gst_gl_colorscale_set_caps (GstBaseTransform * bt, GstCaps * incaps,
    GstCaps * outcaps)
{
  GstGLColorscale *colorscale = GST_GL_COLORSCALE (bt);
  gboolean ret = FALSE;

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

  ret = gst_video_format_parse_caps (outcaps, &colorscale->output_video_format,
      &colorscale->output_video_width, &colorscale->output_video_height);

  ret |= gst_video_format_parse_caps (incaps, &colorscale->input_video_format,
      &colorscale->input_video_width, &colorscale->input_video_height);

  if (!ret) {
    GST_DEBUG ("bad caps");
    return FALSE;
  }

  colorscale->display = gst_gl_display_new ();

  //init unvisible opengl context
  ret = gst_gl_display_create_context (colorscale->display, 0);

  if (!ret) {
    GST_ELEMENT_ERROR (colorscale, RESOURCE, NOT_FOUND,
        (GST_GL_DISPLAY_ERR_MSG (colorscale->display)), (NULL));
    return FALSE;
  }
  //blocking call, init colorspace conversion if needed
  ret = gst_gl_display_init_upload (colorscale->display,
      colorscale->input_video_format, colorscale->output_video_width,
      colorscale->output_video_height, colorscale->input_video_width,
      colorscale->input_video_height);

  if (!ret) {
    GST_ELEMENT_ERROR (colorscale, RESOURCE, NOT_FOUND,
        (GST_GL_DISPLAY_ERR_MSG (colorscale->display)), (NULL));
    return FALSE;
  }
  //blocking call, init colorspace conversion if needed
  ret = gst_gl_display_init_download (colorscale->display,
      colorscale->output_video_format, colorscale->output_video_width,
      colorscale->output_video_height);

  if (!ret)
    GST_ELEMENT_ERROR (colorscale, RESOURCE, NOT_FOUND,
        (GST_GL_DISPLAY_ERR_MSG (colorscale->display)), (NULL));

  return ret;
}

static gboolean
gst_gl_colorscale_get_unit_size (GstBaseTransform * trans, GstCaps * caps,
    guint * size)
{
  gboolean ret;
  GstStructure *structure;
  gint width;
  gint height;

  structure = gst_caps_get_structure (caps, 0);
  if (gst_structure_has_name (structure, "video/x-raw-gl")) {
    ret = gst_gl_buffer_parse_caps (caps, &width, &height);
    if (ret)
      *size = gst_gl_buffer_get_size (width, height);
  } else {
    GstVideoFormat video_format;

    ret = gst_video_format_parse_caps (caps, &video_format, &width, &height);
    if (ret)
      *size = gst_video_format_get_size (video_format, width, height);
  }

  return TRUE;
}

static GstFlowReturn
gst_gl_colorscale_transform (GstBaseTransform * trans, GstBuffer * inbuf,
    GstBuffer * outbuf)
{
  GstGLColorscale *colorscale = GST_GL_COLORSCALE (trans);
  gboolean isAlive = TRUE;

  //blocking call
  GstGLBuffer *gl_temp_buffer = gst_gl_buffer_new (colorscale->display,
      colorscale->output_video_width, colorscale->output_video_height);

  GST_DEBUG ("input size %p size %d",
      GST_BUFFER_DATA (inbuf), GST_BUFFER_SIZE (inbuf));

  //blocking call
  isAlive =
      gst_gl_display_do_upload (colorscale->display, gl_temp_buffer->texture,
      colorscale->input_video_width, colorscale->input_video_height,
      GST_BUFFER_DATA (inbuf));

  GST_DEBUG ("output size %p size %d",
      GST_BUFFER_DATA (outbuf), GST_BUFFER_SIZE (outbuf));

  //blocking call
  isAlive &=
      gst_gl_display_do_download (colorscale->display, gl_temp_buffer->texture,
      gl_temp_buffer->width, gl_temp_buffer->height, GST_BUFFER_DATA (outbuf));

  gst_buffer_unref (GST_BUFFER_CAST (gl_temp_buffer));

  if (isAlive)
    return GST_FLOW_OK;
  else
    return GST_FLOW_UNEXPECTED;
}