/*

 * glshader gstreamer plugin

 * Copyrithg (C) 2008 Filippo Argiolas <filippo.argiolas@gmail.com>

 * Copyright (C) 2009 Luc Deschenaux <luc.deschenaux@freesurf.ch>

 *

 * 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-glshader

 * @title: glshader

 *

 * OpenGL fragment shader filter

 *

 * ## Examples

 * |[

 * gst-launch-1.0 videotestsrc ! glupload ! glshader fragment="\"`cat myshader.frag`\"" ! glimagesink

 * ]|

 * FBO (Frame Buffer Object) and GLSL (OpenGL Shading Language) are required.

 * Depending on the exact OpenGL version chosen and the exact requirements of

 * the OpenGL implementation, a #version header may be required.

 *

 * The following is a simple OpenGL ES (also usable with OpenGL 3 core contexts)

 * passthrough shader with the required inputs.

 * |[

 * #version 100

 * #ifdef GL_ES

 * precision mediump float;

 * #endif

 * varying vec2 v_texcoord;

 * uniform sampler2D tex;

 * uniform float time;

 * uniform float width;

 * uniform float height;

 *

 * void main () {

 *   gl_FragColor = texture2D( tex, v_texcoord );

 * }

 * ]|

 *

 */

#ifdef HAVE_CONFIG_H

#include "config.h"

#endif

#include <gst/gl/gstglfuncs.h>

#include "gstglfiltershader.h"

#ifdef HAVE_GRAPHENE

#include <graphene-gobject.h>

#endif

enum

{

  PROP_0,

  PROP_SHADER,

  PROP_VERTEX,

  PROP_FRAGMENT,

  PROP_UNIFORMS,

  PROP_UPDATE_SHADER,

  PROP_LAST,

};

enum

{

  SIGNAL_0,

  SIGNAL_CREATE_SHADER,

  SIGNAL_LAST,

};

static guint gst_gl_shader_signals[SIGNAL_LAST] = { 0 };

#define GST_CAT_DEFAULT gst_gl_filtershader_debug

GST_DEBUG_CATEGORY_STATIC (GST_CAT_DEFAULT);

#define DEBUG_INIT \

  GST_DEBUG_CATEGORY_INIT (gst_gl_filtershader_debug, "glshader", 0, "glshader element");

#define gst_gl_filtershader_parent_class parent_class

G_DEFINE_TYPE_WITH_CODE (GstGLFilterShader, gst_gl_filtershader,

    GST_TYPE_GL_FILTER, DEBUG_INIT);

static void gst_gl_filtershader_finalize (GObject * object);

static void gst_gl_filtershader_set_property (GObject * object, guint prop_id,

    const GValue * value, GParamSpec * pspec);

static void gst_gl_filtershader_get_property (GObject * object, guint prop_id,

    GValue * value, GParamSpec * pspec);

static gboolean gst_gl_filtershader_gl_start (GstGLBaseFilter * base);

static void gst_gl_filtershader_gl_stop (GstGLBaseFilter * base);

static gboolean gst_gl_filtershader_filter (GstGLFilter * filter,

    GstBuffer * inbuf, GstBuffer * outbuf);

static gboolean gst_gl_filtershader_filter_texture (GstGLFilter * filter,

    GstGLMemory * in_tex, GstGLMemory * out_tex);

static gboolean gst_gl_filtershader_hcallback (GstGLFilter * filter,

    GstGLMemory * in_tex, gpointer stuff);

static void

gst_gl_filtershader_class_init (GstGLFilterShaderClass * klass)

{

  GObjectClass *gobject_class;

  GstElementClass *element_class;

  gobject_class = (GObjectClass *) klass;

  element_class = GST_ELEMENT_CLASS (klass);

  gst_gl_filter_add_rgba_pad_templates (GST_GL_FILTER_CLASS (klass));

  gobject_class->finalize = gst_gl_filtershader_finalize;

  gobject_class->set_property = gst_gl_filtershader_set_property;

  gobject_class->get_property = gst_gl_filtershader_get_property;

  g_object_class_install_property (gobject_class, PROP_SHADER,

      g_param_spec_object ("shader", "Shader object",

          "GstGLShader to use", GST_TYPE_GL_SHADER,

          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

  g_object_class_install_property (gobject_class, PROP_VERTEX,

      g_param_spec_string ("vertex", "Vertex Source",

          "GLSL vertex source", NULL,

          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

  g_object_class_install_property (gobject_class, PROP_FRAGMENT,

      g_param_spec_string ("fragment", "Fragment Source",

          "GLSL fragment source", NULL,

          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

  /* FIXME: add other stages */

  g_object_class_install_property (gobject_class, PROP_UNIFORMS,

      g_param_spec_boxed ("uniforms", "GLSL Uniforms",

          "GLSL Uniforms", GST_TYPE_STRUCTURE,

          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

  g_object_class_install_property (gobject_class, PROP_UPDATE_SHADER,

      g_param_spec_boolean ("update-shader", "Update Shader",

          "Emit the \'create-shader\' signal for the next frame",

          FALSE, G_PARAM_WRITABLE | G_PARAM_STATIC_STRINGS));

  /*

   * GstGLFilterShader::create-shader:

   * @object: the #GstGLFilterShader

   *

   * Ask's the application for a shader to render with as a result of

   * inititialization or setting the 'update-shader' property.

   *

   * Returns: a new #GstGLShader for use in the rendering pipeline

   */

  gst_gl_shader_signals[SIGNAL_CREATE_SHADER] =

      g_signal_new ("create-shader", G_TYPE_FROM_CLASS (klass),

      G_SIGNAL_RUN_LAST, 0, NULL, NULL, g_cclosure_marshal_generic,

      GST_TYPE_GL_SHADER, 0);

  gst_element_class_set_metadata (element_class,

      "OpenGL fragment shader filter", "Filter/Effect",

      "Perform operations with a GLSL shader", "<matthew@centricular.com>");

  GST_GL_FILTER_CLASS (klass)->filter = gst_gl_filtershader_filter;

  GST_GL_FILTER_CLASS (klass)->filter_texture =

      gst_gl_filtershader_filter_texture;

  GST_GL_BASE_FILTER_CLASS (klass)->gl_start = gst_gl_filtershader_gl_start;

  GST_GL_BASE_FILTER_CLASS (klass)->gl_stop = gst_gl_filtershader_gl_stop;

  GST_GL_BASE_FILTER_CLASS (klass)->supported_gl_api =

      GST_GL_API_OPENGL | GST_GL_API_GLES2 | GST_GL_API_OPENGL3;

}

static void

gst_gl_filtershader_init (GstGLFilterShader * filtershader)

{

  filtershader->new_source = TRUE;

}

static void

gst_gl_filtershader_finalize (GObject * object)

{

  GstGLFilterShader *filtershader = GST_GL_FILTERSHADER (object);

  g_free (filtershader->vertex);

  filtershader->vertex = NULL;

  g_free (filtershader->fragment);

  filtershader->fragment = NULL;

  if (filtershader->uniforms)

    gst_structure_free (filtershader->uniforms);

  filtershader->uniforms = NULL;

  G_OBJECT_CLASS (gst_gl_filtershader_parent_class)->finalize (object);

}

static void

gst_gl_filtershader_set_property (GObject * object, guint prop_id,

    const GValue * value, GParamSpec * pspec)

{

  GstGLFilterShader *filtershader = GST_GL_FILTERSHADER (object);

  switch (prop_id) {

    case PROP_SHADER:

      GST_OBJECT_LOCK (filtershader);

      gst_object_replace ((GstObject **) & filtershader->shader,

          g_value_dup_object (value));

      filtershader->new_source = FALSE;

      GST_OBJECT_UNLOCK (filtershader);

      break;

    case PROP_VERTEX:

      GST_OBJECT_LOCK (filtershader);

      g_free (filtershader->vertex);

      filtershader->vertex = g_value_dup_string (value);

      filtershader->new_source = TRUE;

      GST_OBJECT_UNLOCK (filtershader);

      break;

    case PROP_FRAGMENT:

      GST_OBJECT_LOCK (filtershader);

      g_free (filtershader->fragment);

      filtershader->fragment = g_value_dup_string (value);

      filtershader->new_source = TRUE;

      GST_OBJECT_UNLOCK (filtershader);

      break;

    case PROP_UNIFORMS:

      GST_OBJECT_LOCK (filtershader);

      if (filtershader->uniforms)

        gst_structure_free (filtershader->uniforms);

      filtershader->uniforms = g_value_dup_boxed (value);

      filtershader->new_uniforms = TRUE;

      GST_OBJECT_UNLOCK (filtershader);

      break;

    case PROP_UPDATE_SHADER:

      GST_OBJECT_LOCK (filtershader);

      filtershader->update_shader = g_value_get_boolean (value);

      GST_OBJECT_UNLOCK (filtershader);

      break;

    default:

      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);

      break;

  }

}

static void

gst_gl_filtershader_get_property (GObject * object, guint prop_id,

    GValue * value, GParamSpec * pspec)

{

  GstGLFilterShader *filtershader = GST_GL_FILTERSHADER (object);

  switch (prop_id) {

    case PROP_SHADER:

      GST_OBJECT_LOCK (filtershader);

      g_value_set_object (value, filtershader->shader);

      GST_OBJECT_UNLOCK (filtershader);

      break;

    case PROP_VERTEX:

      GST_OBJECT_LOCK (filtershader);

      g_value_set_string (value, filtershader->vertex);

      GST_OBJECT_UNLOCK (filtershader);

      break;

    case PROP_FRAGMENT:

      GST_OBJECT_LOCK (filtershader);

      g_value_set_string (value, filtershader->fragment);

      GST_OBJECT_UNLOCK (filtershader);

      break;

    case PROP_UNIFORMS:

      GST_OBJECT_LOCK (filtershader);

      g_value_set_boxed (value, filtershader->uniforms);

      GST_OBJECT_UNLOCK (filtershader);

      break;

    default:

      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);

      break;

  }

}

static void

gst_gl_filtershader_gl_stop (GstGLBaseFilter * base)

{

  GstGLFilterShader *filtershader = GST_GL_FILTERSHADER (base);

  if (filtershader->shader)

    gst_object_unref (filtershader->shader);

  filtershader->shader = NULL;

  GST_GL_BASE_FILTER_CLASS (parent_class)->gl_stop (base);

}

static gboolean

gst_gl_filtershader_gl_start (GstGLBaseFilter * base)

{

  return GST_GL_BASE_FILTER_CLASS (parent_class)->gl_start (base);

}

static inline gboolean

_gst_clock_time_to_double (GstClockTime time, gdouble * result)

{

  if (!GST_CLOCK_TIME_IS_VALID (time))

    return FALSE;

  *result = (gdouble) time / GST_SECOND;

  return TRUE;

}

static inline gboolean

_gint64_time_val_to_double (gint64 time, gdouble * result)

{

  if (time == -1)

    return FALSE;

  *result = (gdouble) time / GST_USECOND;

  return TRUE;

}

static gboolean

gst_gl_filtershader_filter (GstGLFilter * filter, GstBuffer * inbuf,

    GstBuffer * outbuf)

{

  GstGLFilterShader *filtershader = GST_GL_FILTERSHADER (filter);

  if (!_gst_clock_time_to_double (GST_BUFFER_PTS (inbuf), &filtershader->time)) {

    if (!_gst_clock_time_to_double (GST_BUFFER_DTS (inbuf),

            &filtershader->time))

      _gint64_time_val_to_double (g_get_monotonic_time (), &filtershader->time);

  }

  return gst_gl_filter_filter_texture (filter, inbuf, outbuf);

}

static gboolean

gst_gl_filtershader_filter_texture (GstGLFilter * filter, GstGLMemory * in_tex,

    GstGLMemory * out_tex)

{

  GstGLFilterShader *filtershader = GST_GL_FILTERSHADER (filter);

  gst_gl_filter_render_to_target (filter, in_tex, out_tex,

      gst_gl_filtershader_hcallback, NULL);

  if (!filtershader->shader)

    return FALSE;

  return TRUE;

}

static gboolean

_set_uniform (GQuark field_id, const GValue * value, gpointer user_data)

{

  GstGLShader *shader = user_data;

  const gchar *field_name = g_quark_to_string (field_id);

  if (G_TYPE_CHECK_VALUE_TYPE ((value), G_TYPE_INT)) {

    gst_gl_shader_set_uniform_1i (shader, field_name, g_value_get_int (value));

  } else if (G_TYPE_CHECK_VALUE_TYPE ((value), G_TYPE_FLOAT)) {

    gst_gl_shader_set_uniform_1f (shader, field_name,

        g_value_get_float (value));

#ifdef HAVE_GRAPHENE

  } else if (G_TYPE_CHECK_VALUE_TYPE ((value), GRAPHENE_TYPE_VEC2)) {

    graphene_vec2_t *vec2 = g_value_get_boxed (value);

    float x = graphene_vec2_get_x (vec2);

    float y = graphene_vec2_get_y (vec2);

    gst_gl_shader_set_uniform_2f (shader, field_name, x, y);

  } else if (G_TYPE_CHECK_VALUE_TYPE ((value), GRAPHENE_TYPE_VEC3)) {

    graphene_vec3_t *vec3 = g_value_get_boxed (value);

    float x = graphene_vec3_get_x (vec3);

    float y = graphene_vec3_get_y (vec3);

    float z = graphene_vec3_get_z (vec3);

    gst_gl_shader_set_uniform_3f (shader, field_name, x, y, z);

  } else if (G_TYPE_CHECK_VALUE_TYPE ((value), GRAPHENE_TYPE_VEC4)) {

    graphene_vec4_t *vec4 = g_value_get_boxed (value);

    float x = graphene_vec4_get_x (vec4);

    float y = graphene_vec4_get_y (vec4);

    float z = graphene_vec4_get_z (vec4);

    float w = graphene_vec4_get_w (vec4);

    gst_gl_shader_set_uniform_4f (shader, field_name, x, y, z, w);

  } else if (G_TYPE_CHECK_VALUE_TYPE ((value), GRAPHENE_TYPE_MATRIX)) {

    graphene_matrix_t *matrix = g_value_get_boxed (value);

    float matrix_f[16];

    graphene_matrix_to_float (matrix, matrix_f);

    gst_gl_shader_set_uniform_matrix_4fv (shader, field_name, 1, FALSE,

        matrix_f);

#endif

  } else {

    /* FIXME: Add support for unsigned ints, non 4x4 matrices, etc */

    GST_FIXME ("Don't know how to set the \'%s\' paramater.  Unknown type",

        field_name);

    return TRUE;

  }

  return TRUE;

}

static void

_update_uniforms (GstGLFilterShader * filtershader)

{

  if (filtershader->new_uniforms && filtershader->uniforms) {

    gst_gl_shader_use (filtershader->shader);

    gst_structure_foreach (filtershader->uniforms,

        (GstStructureForeachFunc) _set_uniform, filtershader->shader);

    filtershader->new_uniforms = FALSE;

  }

}

static GstGLShader *

_maybe_recompile_shader (GstGLFilterShader * filtershader)

{

  GstGLContext *context = GST_GL_BASE_FILTER (filtershader)->context;

  GstGLShader *shader;

  GError *error = NULL;

  GST_OBJECT_LOCK (filtershader);

  if (!filtershader->shader || filtershader->update_shader) {

    filtershader->update_shader = FALSE;

    GST_OBJECT_UNLOCK (filtershader);

    g_signal_emit (filtershader, gst_gl_shader_signals[SIGNAL_CREATE_SHADER], 0,

        &shader);

    GST_OBJECT_LOCK (filtershader);

    if (shader) {

      if (filtershader->shader)

        gst_object_unref (filtershader->shader);

      filtershader->new_source = FALSE;

      filtershader->shader = gst_object_ref (shader);

      filtershader->new_uniforms = TRUE;

      _update_uniforms (filtershader);

      GST_OBJECT_UNLOCK (filtershader);

      return shader;

    }

  }

  if (filtershader->shader) {

    shader = gst_object_ref (filtershader->shader);

    _update_uniforms (filtershader);

    GST_OBJECT_UNLOCK (filtershader);

    return shader;

  }

  if (filtershader->new_source) {

    GstGLSLStage *stage;

    shader = gst_gl_shader_new (context);

    if (filtershader->vertex) {

      if (!(stage = gst_glsl_stage_new_with_string (context, GL_VERTEX_SHADER,

                  GST_GLSL_VERSION_NONE, GST_GLSL_PROFILE_NONE,

                  filtershader->vertex))) {

        g_set_error (&error, GST_GLSL_ERROR, GST_GLSL_ERROR_COMPILE,

            "Failed to create shader vertex stage");

        goto print_error;

      }

    } else {

      stage = gst_glsl_stage_new_default_vertex (context);

    }

    if (!gst_gl_shader_compile_attach_stage (shader, stage, &error)) {

      gst_object_unref (stage);

      goto print_error;

    }

    if (filtershader->fragment) {

      if (!(stage = gst_glsl_stage_new_with_string (context, GL_FRAGMENT_SHADER,

                  GST_GLSL_VERSION_NONE, GST_GLSL_PROFILE_NONE,

                  filtershader->fragment))) {

        g_set_error (&error, GST_GLSL_ERROR, GST_GLSL_ERROR_COMPILE,

            "Failed to create shader fragment stage");

        goto print_error;

      }

    } else {

      stage = gst_glsl_stage_new_default_fragment (context);

    }

    if (!gst_gl_shader_compile_attach_stage (shader, stage, &error)) {

      gst_object_unref (stage);

      goto print_error;

    }

    if (!gst_gl_shader_link (shader, &error)) {

      goto print_error;

    }

    if (filtershader->shader)

      gst_object_unref (filtershader->shader);

    filtershader->shader = gst_object_ref (shader);

    filtershader->new_source = FALSE;

    filtershader->new_uniforms = TRUE;

    _update_uniforms (filtershader);

    GST_OBJECT_UNLOCK (filtershader);

    return shader;

  } else if (filtershader->shader) {

    _update_uniforms (filtershader);

    shader = gst_object_ref (filtershader->shader);

    GST_OBJECT_UNLOCK (filtershader);

    return shader;

  }

  return NULL;

print_error:

  if (shader) {

    gst_object_unref (shader);

    shader = NULL;

  }

  GST_OBJECT_UNLOCK (filtershader);

  GST_ELEMENT_ERROR (filtershader, RESOURCE, NOT_FOUND,

      ("%s", error->message), (NULL));

  return NULL;

}

static gboolean

gst_gl_filtershader_hcallback (GstGLFilter * filter, GstGLMemory * in_tex,

    gpointer stuff)

{

  GstGLFilterShader *filtershader = GST_GL_FILTERSHADER (filter);

  GstGLFuncs *gl = GST_GL_BASE_FILTER (filter)->context->gl_vtable;

  GstGLShader *shader;

  if (!(shader = _maybe_recompile_shader (filtershader)))

    return FALSE;

  gl->ClearColor (0.0, 0.0, 0.0, 1.0);

  gl->Clear (GL_COLOR_BUFFER_BIT);

  gst_gl_shader_use (shader);

  /* FIXME: propertise these */

  gst_gl_shader_set_uniform_1i (shader, "tex", 0);

  gst_gl_shader_set_uniform_1f (shader, "width",

      GST_VIDEO_INFO_WIDTH (&filter->out_info));

  gst_gl_shader_set_uniform_1f (shader, "height",

      GST_VIDEO_INFO_HEIGHT (&filter->out_info));

  gst_gl_shader_set_uniform_1f (shader, "time", filtershader->time);

  /* FIXME: propertise these */

  filter->draw_attr_position_loc =

      gst_gl_shader_get_attribute_location (shader, "a_position");

  filter->draw_attr_texture_loc =

      gst_gl_shader_get_attribute_location (shader, "a_texcoord");

  gl->ActiveTexture (GL_TEXTURE0);

  gl->BindTexture (GL_TEXTURE_2D, gst_gl_memory_get_texture_id (in_tex));

  gst_gl_filter_draw_fullscreen_quad (filter);

  gst_object_unref (shader);

  return TRUE;

}