/*

 * GStreamer

 * Copyright (C) 2008-2009 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., 51 Franklin St, Fifth Floor,

 * Boston, MA 02110-1301, USA.

 */

#include <gst/gst.h>

#include <gst/gl/gl.h>

#include <gst/gl/gstglfuncs.h>

#include <iostream>

#include <string>

static gboolean bus_call (GstBus *bus, GstMessage *msg, gpointer data)

{

    GMainLoop *loop = (GMainLoop*)data;

    switch (GST_MESSAGE_TYPE (msg))

    {

        case GST_MESSAGE_EOS:

              g_print ("End-of-stream\n");

              g_main_loop_quit (loop);

              break;

        case GST_MESSAGE_ERROR:

          {

              gchar *debug = NULL;

              GError *err = NULL;

              gst_message_parse_error (msg, &err, &debug);

              g_print ("Error: %s\n", err->message);

              g_error_free (err);

              if (debug)

              {

                  g_print ("Debug deails: %s\n", debug);

                  g_free (debug);

              }

              g_main_loop_quit (loop);

              break;

          }

        default:

          break;

    }

    return TRUE;

}

//client reshape callback

static gboolean reshapeCallback (void *gl_sink, void *context, GLuint width, GLuint height, gpointer data)

{

    glViewport(0, 0, width, height);

    glMatrixMode(GL_PROJECTION);

    glLoadIdentity();

    glMatrixMode(GL_MODELVIEW);

    return TRUE;

}

//client draw callback

static gboolean drawCallback (GstElement * gl_sink, GstGLContext *context, GstSample * sample, gpointer data)

{

    static GLfloat	xrot = 0;

    static GLfloat	yrot = 0;

    static GLfloat	zrot = 0;

    static GTimeVal current_time;

    static glong last_sec = current_time.tv_sec;

    static gint nbFrames = 0;

    GstVideoFrame v_frame;

    GstVideoInfo v_info;

    guint texture = 0;

    GstBuffer *buf = gst_sample_get_buffer (sample);

    GstCaps *caps = gst_sample_get_caps (sample);

    gst_video_info_from_caps (&v_info, caps);

    if (!gst_video_frame_map (&v_frame, &v_info, buf, (GstMapFlags) (GST_MAP_READ | GST_MAP_GL))) {

      g_warning ("Failed to map the video buffer");

      return TRUE;

    }

    texture = *(guint *) v_frame.data[0];

    g_get_current_time (&current_time);

    nbFrames++ ;

    if ((current_time.tv_sec - last_sec) >= 1)

    {

        std::cout << "GRPHIC FPS = " << nbFrames << std::endl;

        nbFrames = 0;

        last_sec = current_time.tv_sec;

    }

    glEnable(GL_DEPTH_TEST);

    glEnable (GL_TEXTURE_2D);

    glBindTexture (GL_TEXTURE_2D, texture);

    glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);

    glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);

    glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);

    glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);

    glTexEnvi (GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    glMatrixMode(GL_MODELVIEW);

    glLoadIdentity();

    /* invert the y-axis to get the front face the correct way up */

    glScalef (0.5f, -0.5f, 0.5f);

    glRotatef(xrot,1.0f,0.0f,0.0f);

    glRotatef(yrot,0.0f,1.0f,0.0f);

    glRotatef(zrot,0.0f,0.0f,1.0f);

    glBegin(GL_QUADS);

	      // Front Face

	      glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f,  1.0f);

	      glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f,  1.0f);

	      glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f,  1.0f,  1.0f);

	      glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f,  1.0f,  1.0f);

	      // Back Face

	      glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, -1.0f, -1.0f);

	      glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f,  1.0f, -1.0f);

	      glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f,  1.0f, -1.0f);

	      glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, -1.0f, -1.0f);

	      // Top Face

	      glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f,  1.0f, -1.0f);

	      glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f,  1.0f,  1.0f);

	      glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f,  1.0f,  1.0f);

	      glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f,  1.0f, -1.0f);

	      // Bottom Face

	      glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f, -1.0f);

	      glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f, -1.0f);

	      glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f, -1.0f,  1.0f);

	      glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f, -1.0f,  1.0f);

	      // Right face

	      glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f, -1.0f);

	      glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f,  1.0f, -1.0f);

	      glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f,  1.0f,  1.0f);

	      glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, -1.0f,  1.0f);

	      // Left Face

	      glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f, -1.0f);

	      glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, -1.0f,  1.0f);

	      glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f,  1.0f,  1.0f);

	      glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f,  1.0f, -1.0f);

    glEnd();

    gst_video_frame_unmap (&v_frame);

    xrot+=0.3f;

    yrot+=0.2f;

    zrot+=0.4f;

    glDisable (GL_DEPTH_TEST);

    glDisable (GL_TEXTURE_2D);

    return TRUE;

}

//gst-launch-1.0 videotestsrc num_buffers=400 ! video/x-raw, width=320, height=240 !

//glgraphicmaker ! glfiltercube ! video/x-raw, width=800, height=600 ! glimagesink

gint main (gint argc, gchar *argv[])

{

    GstStateChangeReturn ret;

    GstElement *pipeline, *videosrc, *glimagesink;

    GMainLoop *loop;

    GstBus *bus;

    /* FIXME: remove once the example supports gl3 and/or gles2 */

    g_setenv ("GST_GL_API", "opengl", FALSE);

    /* initialization */

    gst_init (&argc, &argv);

    loop = g_main_loop_new (NULL, FALSE);

    /* create elements */

    pipeline = gst_pipeline_new ("pipeline");

    /* watch for messages on the pipeline's bus (note that this will only

     * work like this when a GLib main loop is running) */

    bus = gst_pipeline_get_bus (GST_PIPELINE (pipeline));

    gst_bus_add_watch (bus, bus_call, loop);

    gst_object_unref (bus);

    /* create elements */

    videosrc = gst_element_factory_make ("videotestsrc", "videotestsrc0");

    glimagesink  = gst_element_factory_make ("glimagesink", "glimagesink0");

    if (!videosrc || !glimagesink)

    {

        g_print ("one element could not be found \n");

        return -1;

    }

    /* change video source caps */

    GstCaps *caps = gst_caps_new_simple("video/x-raw",

                                        "format", G_TYPE_STRING, "RGB",

                                        "width", G_TYPE_INT, 320,

                                        "height", G_TYPE_INT, 240,

                                        "framerate", GST_TYPE_FRACTION, 25, 1,

                                        NULL) ;

    /* configure elements */

    g_object_set(G_OBJECT(videosrc), "num-buffers", 400, NULL);

    g_signal_connect(G_OBJECT(glimagesink), "client-reshape", G_CALLBACK (reshapeCallback), NULL);

    g_signal_connect(G_OBJECT(glimagesink), "client-draw", G_CALLBACK (drawCallback), NULL);

    /* add elements */

    gst_bin_add_many (GST_BIN (pipeline), videosrc, glimagesink, NULL);

    /* link elements */

    gboolean link_ok = gst_element_link_filtered(videosrc, glimagesink, caps) ;

    gst_caps_unref(caps) ;

    if(!link_ok)

    {

        g_warning("Failed to link videosrc to glimagesink!\n") ;

        return -1 ;

    }

    /* run */

    ret = gst_element_set_state (pipeline, GST_STATE_PLAYING);

    if (ret == GST_STATE_CHANGE_FAILURE)

    {

        g_print ("Failed to start up pipeline!\n");

        /* check if there is an error message with details on the bus */

        GstMessage* msg = gst_bus_poll (bus, GST_MESSAGE_ERROR, 0);

        if (msg)

        {

          GError *err = NULL;

          gst_message_parse_error (msg, &err, NULL);

          g_print ("ERROR: %s\n", err->message);

          g_error_free (err);

          gst_message_unref (msg);

        }

        return -1;

    }

    g_main_loop_run (loop);

    /* clean up */

    gst_element_set_state (pipeline, GST_STATE_NULL);

    gst_object_unref (pipeline);

    return 0;

}