/* GStreamer
 * Copyright (C) 2004 Benjamin Otte <otte@gnome.org>
 * Copyright (C) 2009 Jonathan Matthew <notverysmart@gmail.com>
 * Copyright (C) 2011 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.
 */

/**
 * SECTION:element-libvisualgl
 *
 * Wrapper for libvisual plugins that use OpenGL
 *
 * <refsect2>
 * <title>Examples</title>
 * |[
 * gst-launch-1.0 -v audiotestsrc ! libvisual_gl_lv_flower ! glimagesink
 * ]|
 * </refsect2>
 */

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

#include <gst/gst.h>
#include <gst/base/gstadapter.h>
#include <gst/video/video.h>
#include <gst/audio/audio.h>
#include <gst/gl/gstglbuffer.h>
#include <gst/gl/gstgldisplay.h>

#include <libvisual/libvisual.h>

#define GST_TYPE_VISUAL_GL (gst_visual_gl_get_type())
#define GST_IS_VISUAL_GL(obj) (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_VISUAL_GL))
#define GST_VISUAL_GL(obj) (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_VISUAL_GL,GstVisualGL))
#define GST_IS_VISUAL_GL_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_VISUAL_GL))
#define GST_VISUAL_GL_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_VISUAL_GL,GstVisualGLClass))
#define GST_VISUAL_GL_GET_CLASS(obj)   (G_TYPE_INSTANCE_GET_CLASS ((obj), GST_TYPE_VISUAL_GL, GstVisualGLClass))

typedef struct _GstVisualGL GstVisualGL;
typedef struct _GstVisualGLClass GstVisualGLClass;

/* XXX use same category as libvisual plugin in -base? */
GST_DEBUG_CATEGORY_STATIC (libvisual_debug);
#define GST_CAT_DEFAULT (libvisual_debug)

/* amounf of samples before we can feed libvisual */
#define VISUAL_SAMPLES  512

#define DEFAULT_WIDTH   320
#define DEFAULT_HEIGHT  240
#define DEFAULT_FPS_N   25
#define DEFAULT_FPS_D   1

struct _GstVisualGL
{
  GstElement element;

  /* pads */
  GstPad *sinkpad;
  GstPad *srcpad;
  GstSegment segment;

  /* GL stuff */
  GstGLDisplay *display;
  GLuint fbo;
  GLuint depthbuffer;
  GLuint midtexture;
  GLdouble actor_projection_matrix[16];
  GLdouble actor_modelview_matrix[16];
  GLboolean is_enabled_gl_depth_test;
  GLint gl_depth_func;
  GLboolean is_enabled_gl_blend;
  GLint gl_blend_src_alpha;

  /* libvisual stuff */
  VisAudio *audio;
  VisVideo *video;
  VisActor *actor;
  int actor_setup_result;

  /* audio/video state */
  gint channels;
  gint rate;                    /* Input samplerate */
  gint bps;
  VisAudioSampleRateType libvisual_rate;

  /* framerate numerator & denominator */
  gint fps_n;
  gint fps_d;
  gint width;
  gint height;
  GstClockTime duration;
  guint outsize;

  /* samples per frame based on caps */
  guint spf;

  /* state stuff */
  GstAdapter *adapter;
  guint count;

  /* QoS stuff *//* with LOCK */
  gdouble proportion;
  GstClockTime earliest_time;
};

struct _GstVisualGLClass
{
  GstElementClass parent_class;

  VisPluginRef *plugin;
};

GType gst_visual_gl_get_type (void);


static GstStaticPadTemplate src_template = GST_STATIC_PAD_TEMPLATE ("src",
    GST_PAD_SRC,
    GST_PAD_ALWAYS,
    GST_STATIC_CAPS (GST_GL_VIDEO_CAPS)
    );

static GstStaticPadTemplate sink_template = GST_STATIC_PAD_TEMPLATE ("sink",
    GST_PAD_SINK,
    GST_PAD_ALWAYS,
    GST_STATIC_CAPS ("audio/x-raw-int, "
        "width = (int) 16, "
        "depth = (int) 16, "
        "endianness = (int) BYTE_ORDER, "
        "signed = (boolean) TRUE, " "channels = (int) { 1, 2 }, "
        "rate = (int) { 8000, 11250, 22500, 32000, 44100, 48000, 96000 }")
    );


static void gst_visual_gl_class_init (gpointer g_class, gpointer class_data);
static void gst_visual_gl_init (GstVisualGL * visual);
static void gst_visual_gl_dispose (GObject * object);

static GstStateChangeReturn gst_visual_gl_change_state (GstElement * element,
    GstStateChange transition);
static GstFlowReturn gst_visual_gl_chain (GstPad * pad, GstBuffer * buffer);
static gboolean gst_visual_gl_sink_event (GstPad * pad, GstEvent * event);
static gboolean gst_visual_gl_src_event (GstPad * pad, GstEvent * event);

static gboolean gst_visual_gl_src_query (GstPad * pad, GstQuery * query);

static gboolean gst_visual_gl_sink_setcaps (GstPad * pad, GstCaps * caps);
static gboolean gst_visual_gl_src_setcaps (GstPad * pad, GstCaps * caps);
static GstCaps *gst_visual_gl_getcaps (GstPad * pad);
static void libvisual_log_handler (const char *message, const char *funcname,
    void *priv);

static GstElementClass *parent_class = NULL;

GType
gst_visual_gl_get_type (void)
{
  static GType type = 0;

  if (G_UNLIKELY (type == 0)) {
    static const GTypeInfo info = {
      sizeof (GstVisualGLClass),
      NULL,
      NULL,
      gst_visual_gl_class_init,
      NULL,
      NULL,
      sizeof (GstVisualGL),
      0,
      (GInstanceInitFunc) gst_visual_gl_init,
    };

    type = g_type_register_static (GST_TYPE_ELEMENT, "GstVisualGL", &info, 0);
  }
  return type;
}

static void
libvisual_log_handler (const char *message, const char *funcname, void *priv)
{
  GST_CAT_LEVEL_LOG (libvisual_debug, (GstDebugLevel) (priv), NULL, "%s - %s",
      funcname, message);
}

static void
gst_visual_gl_class_init (gpointer g_class, gpointer class_data)
{
  GstVisualGLClass *klass = GST_VISUAL_GL_CLASS (g_class);
  GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);
  GObjectClass *object = G_OBJECT_CLASS (g_class);

  klass->plugin = class_data;

  element_class->change_state = gst_visual_gl_change_state;

  if (class_data == NULL) {
    parent_class = g_type_class_peek_parent (g_class);
  } else {
    char *longname = g_strdup_printf ("libvisual %s plugin v.%s",
        klass->plugin->info->name, klass->plugin->info->version);

    /* FIXME: improve to only register what plugin supports? */
    gst_element_class_add_static_pad_template (element_class, &src_template);
    gst_element_class_add_static_pad_template (element_class, &sink_template);

    gst_element_class_set_metadata (element_class,
        longname, "Visualization", klass->plugin->info->about,
        "Benjamin Otte <otte@gnome.org>");

    g_free (longname);
  }

  object->dispose = gst_visual_gl_dispose;
}

static void
gst_visual_gl_init (GstVisualGL * visual)
{
  /* create the sink and src pads */
  visual->sinkpad = gst_pad_new_from_static_template (&sink_template, "sink");
  gst_pad_set_setcaps_function (visual->sinkpad, gst_visual_gl_sink_setcaps);
  gst_pad_set_chain_function (visual->sinkpad, gst_visual_gl_chain);
  gst_pad_set_event_function (visual->sinkpad, gst_visual_gl_sink_event);
  gst_element_add_pad (GST_ELEMENT (visual), visual->sinkpad);

  visual->srcpad = gst_pad_new_from_static_template (&src_template, "src");
  gst_pad_set_setcaps_function (visual->srcpad, gst_visual_gl_src_setcaps);
  gst_pad_set_getcaps_function (visual->srcpad, gst_visual_gl_getcaps);
  gst_pad_set_event_function (visual->srcpad, gst_visual_gl_src_event);
  gst_pad_set_query_function (visual->srcpad, gst_visual_gl_src_query);
  gst_element_add_pad (GST_ELEMENT (visual), visual->srcpad);

  visual->adapter = gst_adapter_new ();

  visual->actor = NULL;

  visual->display = NULL;
  visual->fbo = 0;
  visual->depthbuffer = 0;
  visual->midtexture = 0;

  visual->is_enabled_gl_depth_test = GL_FALSE;
  visual->gl_depth_func = GL_LESS;
  visual->is_enabled_gl_blend = GL_FALSE;
  visual->gl_blend_src_alpha = GL_ONE;
}

static void
gst_visual_gl_clear_actors (GstVisualGL * visual)
{
  if (visual->actor) {
    visual_object_unref (VISUAL_OBJECT (visual->actor));
    visual->actor = NULL;
  }
  if (visual->video) {
    visual_object_unref (VISUAL_OBJECT (visual->video));
    visual->video = NULL;
  }
  if (visual->audio) {
    visual_object_unref (VISUAL_OBJECT (visual->audio));
    visual->audio = NULL;
  }
}

static void
gst_visual_gl_dispose (GObject * object)
{
  GstVisualGL *visual = GST_VISUAL_GL (object);

  if (visual->adapter) {
    gst_object_unref (visual->adapter);
    visual->adapter = NULL;
  }

  GST_CALL_PARENT (G_OBJECT_CLASS, dispose, (object));
}

static void
gst_visual_gl_reset (GstVisualGL * visual)
{
  gst_adapter_clear (visual->adapter);
  gst_segment_init (&visual->segment, GST_FORMAT_UNDEFINED);

  GST_OBJECT_LOCK (visual);
  visual->proportion = 1.0;
  visual->earliest_time = -1;
  GST_OBJECT_UNLOCK (visual);
}

static GstCaps *
gst_visual_gl_getcaps (GstPad * pad)
{
  GstCaps *ret;
  GstVisualGL *visual = GST_VISUAL_GL (gst_pad_get_parent (pad));
  int depths;

  if (!visual->actor) {
    ret = gst_caps_copy (gst_pad_get_pad_template_caps (visual->srcpad));
    goto beach;
  }

  ret = gst_caps_new_empty ();
  depths = visual_actor_get_supported_depth (visual->actor);
  if (depths < 0) {
    /* FIXME: set an error */
    goto beach;
  }
  if ((depths & VISUAL_VIDEO_DEPTH_GL) == 0) {
    /* We don't handle non-GL plugins */
    goto beach;
  }

  GST_DEBUG_OBJECT (visual, "libvisual-gl plugin supports depths %u (0x%04x)",
      depths, depths);
  /* only do GL output */
  gst_caps_append (ret, gst_caps_from_string (GST_GL_VIDEO_CAPS));

beach:

  GST_DEBUG_OBJECT (visual, "returning caps %" GST_PTR_FORMAT, ret);
  gst_object_unref (visual);
  return ret;
}

static gboolean
gst_visual_gl_src_setcaps (GstPad * pad, GstCaps * caps)
{
  GstVisualGL *visual = GST_VISUAL_GL (gst_pad_get_parent (pad));
  GstStructure *structure;

  structure = gst_caps_get_structure (caps, 0);

  GST_DEBUG_OBJECT (visual, "src pad got caps %" GST_PTR_FORMAT, caps);

  if (!gst_structure_get_int (structure, "width", &visual->width))
    goto error;
  if (!gst_structure_get_int (structure, "height", &visual->height))
    goto error;
  if (!gst_structure_get_fraction (structure, "framerate", &visual->fps_n,
          &visual->fps_d))
    goto error;

  /* precalc some values */
  visual->spf =
      gst_util_uint64_scale_int (visual->rate, visual->fps_d, visual->fps_n);
  visual->duration =
      gst_util_uint64_scale_int (GST_SECOND, visual->fps_d, visual->fps_n);

  gst_gl_display_gen_texture (visual->display, &visual->midtexture,
      visual->width, visual->height);

  gst_gl_display_gen_fbo (visual->display, visual->width, visual->height,
      &visual->fbo, &visual->depthbuffer);

  gst_object_unref (visual);
  return TRUE;

  /* ERRORS */
error:
  {
    GST_DEBUG_OBJECT (visual, "error parsing caps");
    gst_object_unref (visual);
    return FALSE;
  }
}

static gboolean
gst_visual_gl_sink_setcaps (GstPad * pad, GstCaps * caps)
{
  GstVisualGL *visual = GST_VISUAL_GL (gst_pad_get_parent (pad));
  GstStructure *structure;

  structure = gst_caps_get_structure (caps, 0);

  gst_structure_get_int (structure, "channels", &visual->channels);
  gst_structure_get_int (structure, "rate", &visual->rate);

  switch (visual->rate) {
    case 8000:
      visual->libvisual_rate = VISUAL_AUDIO_SAMPLE_RATE_8000;
      break;
    case 11250:
      visual->libvisual_rate = VISUAL_AUDIO_SAMPLE_RATE_11250;
      break;
    case 22500:
      visual->libvisual_rate = VISUAL_AUDIO_SAMPLE_RATE_22500;
      break;
    case 32000:
      visual->libvisual_rate = VISUAL_AUDIO_SAMPLE_RATE_32000;
      break;
    case 44100:
      visual->libvisual_rate = VISUAL_AUDIO_SAMPLE_RATE_44100;
      break;
    case 48000:
      visual->libvisual_rate = VISUAL_AUDIO_SAMPLE_RATE_48000;
      break;
    case 96000:
      visual->libvisual_rate = VISUAL_AUDIO_SAMPLE_RATE_96000;
      break;
    default:
      gst_object_unref (visual);
      return FALSE;
  }

  /* this is how many samples we need to fill one frame at the requested
   * framerate. */
  if (visual->fps_n != 0) {
    visual->spf =
        gst_util_uint64_scale_int (visual->rate, visual->fps_d, visual->fps_n);
  }
  visual->bps = visual->channels * sizeof (gint16);

  gst_object_unref (visual);
  return TRUE;
}

static gboolean
gst_vis_gl_src_negotiate (GstVisualGL * visual)
{
  GstCaps *othercaps, *target;
  GstStructure *structure;
  GstCaps *caps;

  caps = gst_pad_get_caps (visual->srcpad);

  /* see what the peer can do */
  othercaps = gst_pad_peer_get_caps (visual->srcpad);
  if (othercaps) {
    target = gst_caps_intersect (othercaps, caps);
    gst_caps_unref (othercaps);
    gst_caps_unref (caps);

    if (gst_caps_is_empty (target))
      goto no_format;

    gst_caps_truncate (target);
  } else {
    /* need a copy, we'll be modifying it when fixating */
    target = gst_caps_copy (caps);
    gst_caps_unref (caps);
  }

  /* fixate in case something is not fixed. This does nothing if the value is
   * already fixed. For video we always try to fixate to something like
   * 320x240x25 by convention. */
  structure = gst_caps_get_structure (target, 0);
  gst_structure_fixate_field_nearest_int (structure, "width", DEFAULT_WIDTH);
  gst_structure_fixate_field_nearest_int (structure, "height", DEFAULT_HEIGHT);
  gst_structure_fixate_field_nearest_fraction (structure, "framerate",
      DEFAULT_FPS_N, DEFAULT_FPS_D);

  gst_pad_set_caps (visual->srcpad, target);
  gst_caps_unref (target);

  return TRUE;

  /* ERRORS */
no_format:
  {
    GST_ELEMENT_ERROR (visual, STREAM, FORMAT, (NULL),
        ("could not negotiate output format"));
    gst_caps_unref (target);
    return FALSE;
  }
}

static gboolean
gst_visual_gl_sink_event (GstPad * pad, GstEvent * event)
{
  GstVisualGL *visual;
  gboolean res;

  visual = GST_VISUAL_GL (gst_pad_get_parent (pad));

  switch (GST_EVENT_TYPE (event)) {
    case GST_EVENT_FLUSH_START:
      res = gst_pad_push_event (visual->srcpad, event);
      break;
    case GST_EVENT_FLUSH_STOP:
      /* reset QoS and adapter. */
      gst_visual_gl_reset (visual);
      res = gst_pad_push_event (visual->srcpad, event);
      break;
    case GST_EVENT_NEWSEGMENT:
    {
      GstFormat format;
      gdouble rate, arate;
      gint64 start, stop, time;
      gboolean update;

      /* the newsegment values are used to clip the input samples
       * and to convert the incomming timestamps to running time so
       * we can do QoS */
      gst_event_parse_new_segment_full (event, &update, &rate, &arate, &format,
          &start, &stop, &time);

      /* now configure the values */
      gst_segment_set_newsegment_full (&visual->segment, update,
          rate, arate, format, start, stop, time);

      /* and forward */
      res = gst_pad_push_event (visual->srcpad, event);
      break;
    }
    default:
      res = gst_pad_push_event (visual->srcpad, event);
      break;
  }

  gst_object_unref (visual);
  return res;
}

static gboolean
gst_visual_gl_src_event (GstPad * pad, GstEvent * event)
{
  GstVisualGL *visual;
  gboolean res;

  visual = GST_VISUAL_GL (gst_pad_get_parent (pad));

  switch (GST_EVENT_TYPE (event)) {
    case GST_EVENT_QOS:
    {
      gdouble proportion;
      GstClockTimeDiff diff;
      GstClockTime timestamp;

      gst_event_parse_qos (event, &proportion, &diff, &timestamp);

      /* save stuff for the _chain function */
      GST_OBJECT_LOCK (visual);
      visual->proportion = proportion;
      if (diff >= 0)
        /* we're late, this is a good estimate for next displayable
         * frame (see part-qos.txt) */
        visual->earliest_time = timestamp + 2 * diff + visual->duration;
      else
        visual->earliest_time = timestamp + diff;

      GST_OBJECT_UNLOCK (visual);

      res = gst_pad_push_event (visual->sinkpad, event);
      break;
    }
    default:
      res = gst_pad_push_event (visual->sinkpad, event);
      break;
  }

  gst_object_unref (visual);
  return res;
}

static gboolean
gst_visual_gl_src_query (GstPad * pad, GstQuery * query)
{
  gboolean res;
  GstVisualGL *visual;

  visual = GST_VISUAL_GL (gst_pad_get_parent (pad));

  switch (GST_QUERY_TYPE (query)) {
    case GST_QUERY_LATENCY:
    {
      /* We need to send the query upstream and add the returned latency to our
       * own */
      GstClockTime min_latency, max_latency;
      gboolean us_live;
      GstClockTime our_latency;
      guint max_samples;

      if ((res = gst_pad_peer_query (visual->sinkpad, query))) {
        gst_query_parse_latency (query, &us_live, &min_latency, &max_latency);

        GST_DEBUG_OBJECT (visual, "Peer latency: min %"
            GST_TIME_FORMAT " max %" GST_TIME_FORMAT,
            GST_TIME_ARGS (min_latency), GST_TIME_ARGS (max_latency));

        /* the max samples we must buffer buffer */
        max_samples = MAX (VISUAL_SAMPLES, visual->spf);
        our_latency =
            gst_util_uint64_scale_int (max_samples, GST_SECOND, visual->rate);

        GST_DEBUG_OBJECT (visual, "Our latency: %" GST_TIME_FORMAT,
            GST_TIME_ARGS (our_latency));

        /* we add some latency but only if we need to buffer more than what
         * upstream gives us */
        min_latency += our_latency;
        if (max_latency != -1)
          max_latency += our_latency;

        GST_DEBUG_OBJECT (visual, "Calculated total latency : min %"
            GST_TIME_FORMAT " max %" GST_TIME_FORMAT,
            GST_TIME_ARGS (min_latency), GST_TIME_ARGS (max_latency));

        gst_query_set_latency (query, TRUE, min_latency, max_latency);
      }
      break;
    }
    case GST_QUERY_CUSTOM:
    {
      GstStructure *structure = gst_query_get_structure (query);
      gchar *name = gst_element_get_name (visual);

      res = g_strcmp0 (name, gst_structure_get_name (structure)) == 0;
      g_free (name);

      if (!res)
        res = gst_pad_query_default (pad, query);
      break;
    }
    default:
      res = gst_pad_peer_query (visual->sinkpad, query);
      break;
  }

  gst_object_unref (visual);

  return res;
}

/* allocate and output buffer, if no format was negotiated, this
 * function will negotiate one. After calling this function, a
 * reverse negotiation could have happened. */
static GstFlowReturn
get_buffer (GstVisualGL * visual, GstGLBuffer ** outbuf)
{
  /* we don't know an output format yet, pick one */
  if (GST_PAD_CAPS (visual->srcpad) == NULL) {
    if (!gst_vis_gl_src_negotiate (visual))
      return GST_FLOW_NOT_NEGOTIATED;
  }

  GST_DEBUG_OBJECT (visual, "allocating output buffer with caps %"
      GST_PTR_FORMAT, GST_PAD_CAPS (visual->srcpad));

  *outbuf = gst_gl_buffer_new (visual->display, visual->width, visual->height);
  if (*outbuf == NULL)
    return GST_FLOW_ERROR;

  gst_buffer_set_caps (GST_BUFFER (*outbuf), GST_PAD_CAPS (visual->srcpad));
  return GST_FLOW_OK;
}

static void
actor_setup (GstGLDisplay * display, GstVisualGL * visual)
{
  /* save and clear top of the stack */
  glPushAttrib (GL_ALL_ATTRIB_BITS);

  glMatrixMode (GL_PROJECTION);
  glPushMatrix ();
  glLoadIdentity ();

  glMatrixMode (GL_MODELVIEW);
  glPushMatrix ();
  glLoadIdentity ();

  visual->actor_setup_result = visual_actor_realize (visual->actor);
  if (visual->actor_setup_result == 0) {
    /* store the actor's matrices for rendering the first frame */
    glGetDoublev (GL_MODELVIEW_MATRIX, visual->actor_modelview_matrix);
    glGetDoublev (GL_PROJECTION_MATRIX, visual->actor_projection_matrix);

    visual->is_enabled_gl_depth_test = glIsEnabled (GL_DEPTH_TEST);
    glGetIntegerv (GL_DEPTH_FUNC, &visual->gl_depth_func);

    visual->is_enabled_gl_blend = glIsEnabled (GL_BLEND);
    glGetIntegerv (GL_BLEND_SRC_ALPHA, &visual->gl_blend_src_alpha);

    /* retore matrix */
    glMatrixMode (GL_PROJECTION);
    glPopMatrix ();

    glMatrixMode (GL_MODELVIEW);
    glPopMatrix ();

    glPopAttrib ();
  }
}

static void
actor_negotiate (GstGLDisplay * display, GstVisualGL * visual)
{
  gint err = VISUAL_OK;

  err = visual_video_set_depth (visual->video, VISUAL_VIDEO_DEPTH_GL);
  if (err != VISUAL_OK)
    g_warning ("failed to visual_video_set_depth\n");

  err =
      visual_video_set_dimension (visual->video, visual->width, visual->height);
  if (err != VISUAL_OK)
    g_warning ("failed to visual_video_set_dimension\n");

  err = visual_actor_video_negotiate (visual->actor, 0, FALSE, FALSE);
  if (err != VISUAL_OK)
    g_warning ("failed to visual_actor_video_negotiate\n");
}

static void
check_gl_matrix (void)
{
  GLdouble projection_matrix[16];
  GLdouble modelview_matrix[16];
  gint i = 0;
  gint j = 0;

  glGetDoublev (GL_PROJECTION_MATRIX, projection_matrix);
  glGetDoublev (GL_MODELVIEW_MATRIX, modelview_matrix);

  for (j = 0; j < 4; ++j) {
    for (i = 0; i < 4; ++i) {
      if (projection_matrix[i + 4 * j] != projection_matrix[i + 4 * j])
        g_warning ("invalid projection matrix at coordiante %dx%d: %f\n", i, j,
            projection_matrix[i + 4 * j]);
      if (modelview_matrix[i + 4 * j] != modelview_matrix[i + 4 * j])
        g_warning ("invalid modelview_matrix matrix at coordiante %dx%d: %f\n",
            i, j, modelview_matrix[i + 4 * j]);
    }
  }
}

static void
render_frame (GstVisualGL * visual)
{
  const guint16 *data;
  VisBuffer *lbuf, *rbuf;
  guint16 ldata[VISUAL_SAMPLES], rdata[VISUAL_SAMPLES];
  guint i;
  gcahr *name;

  /* Read VISUAL_SAMPLES samples per channel */
  data =
      (const guint16 *) gst_adapter_peek (visual->adapter,
      VISUAL_SAMPLES * visual->bps);

  lbuf = visual_buffer_new_with_buffer (ldata, sizeof (ldata), NULL);
  rbuf = visual_buffer_new_with_buffer (rdata, sizeof (rdata), NULL);

  if (visual->channels == 2) {
    for (i = 0; i < VISUAL_SAMPLES; i++) {
      ldata[i] = *data++;
      rdata[i] = *data++;
    }
  } else {
    for (i = 0; i < VISUAL_SAMPLES; i++) {
      ldata[i] = *data;
      rdata[i] = *data++;
    }
  }

  visual_audio_samplepool_input_channel (visual->audio->samplepool,
      lbuf, visual->libvisual_rate, VISUAL_AUDIO_SAMPLE_FORMAT_S16,
      VISUAL_AUDIO_CHANNEL_LEFT);
  visual_audio_samplepool_input_channel (visual->audio->samplepool,
      rbuf, visual->libvisual_rate, VISUAL_AUDIO_SAMPLE_FORMAT_S16,
      VISUAL_AUDIO_CHANNEL_RIGHT);

  visual_object_unref (VISUAL_OBJECT (lbuf));
  visual_object_unref (VISUAL_OBJECT (rbuf));

  visual_audio_analyze (visual->audio);

  /* apply the matrices that the actor set up */
  glPushAttrib (GL_ALL_ATTRIB_BITS);

  glMatrixMode (GL_PROJECTION);
  glPushMatrix ();
  glLoadMatrixd (visual->actor_projection_matrix);

  glMatrixMode (GL_MODELVIEW);
  glPushMatrix ();
  glLoadMatrixd (visual->actor_modelview_matrix);

  /* This line try to hacks compatiblity with libprojectM
   * If libprojectM version <= 2.0.0 then we have to unbind our current
   * fbo to see something. But it's incorrect and we cannot use fbo chainning (append other glfilters
   * after libvisual_gl_projectM will not work)
   * To have full compatibility, libprojectM needs to take care of our fbo.
   * Indeed libprojectM has to unbind it before the first rendering pass
   * and then rebind it before the final pass. It's done from 2.0.1
   */
  name = gst_element_get_name (GST_ELEMENT (visual));
  if (g_ascii_strncasecmp (name, "visualglprojectm", 16) == 0
      && !HAVE_PROJECTM_TAKING_CARE_OF_EXTERNAL_FBO)
    glBindFramebufferEXT (GL_FRAMEBUFFER_EXT, 0);
  g_free (name);

  actor_negotiate (visual->display, visual);

  if (visual->is_enabled_gl_depth_test) {
    glEnable (GL_DEPTH_TEST);
    glDepthFunc (visual->gl_depth_func);
  }

  if (visual->is_enabled_gl_blend) {
    glEnable (GL_BLEND);
    glBlendFunc (visual->gl_blend_src_alpha, GL_ZERO);
  }

  visual_actor_run (visual->actor, visual->audio);

  check_gl_matrix ();

  glMatrixMode (GL_PROJECTION);
  glPopMatrix ();

  glMatrixMode (GL_MODELVIEW);
  glPopMatrix ();

  glPopAttrib ();

  glDisable (GL_DEPTH_TEST);
  glDisable (GL_BLEND);

  /*glDisable (GL_LIGHT0);
     glDisable (GL_LIGHTING);
     glDisable (GL_POLYGON_OFFSET_FILL);
     glDisable (GL_COLOR_MATERIAL);
     glDisable (GL_CULL_FACE); */

  GST_DEBUG_OBJECT (visual, "rendered one frame");
}

static void
bottom_up_to_top_down (gint width, gint height, guint texture,
    GstVisualGL * visual)
{

  glEnable (GL_TEXTURE_2D);
  glBindTexture (GL_TEXTURE_2D, texture);

  glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

  glMatrixMode (GL_PROJECTION);
  glLoadIdentity ();

  glBegin (GL_QUADS);
  glTexCoord2i (0, 0);
  glVertex2i (-1, 1);
  glTexCoord2i (width, 0);
  glVertex2i (1, 1);
  glTexCoord2i (width, height);
  glVertex2i (1, -1);
  glTexCoord2i (0, height);
  glVertex2i (-1, -1);
  glEnd ();

  glBindTexture (GL_TEXTURE_2D, 0);
  glDisable (GL_TEXTURE_2D);

  GST_DEBUG_OBJECT (visual, "bottom up to top down");
}

static GstFlowReturn
gst_visual_gl_chain (GstPad * pad, GstBuffer * buffer)
{
  GstGLBuffer *outbuf = NULL;
  GstVisualGL *visual = GST_VISUAL_GL (gst_pad_get_parent (pad));
  GstFlowReturn ret = GST_FLOW_OK;
  guint avail;

  GST_DEBUG_OBJECT (visual, "chain function called");

  /* If we don't have an output format yet, preallocate a buffer to try and
   * set one */
  if (GST_PAD_CAPS (visual->srcpad) == NULL) {
    ret = get_buffer (visual, &outbuf);
    if (ret != GST_FLOW_OK) {
      gst_buffer_unref (buffer);
      goto beach;
    }
  }

  /* resync on DISCONT */
  if (GST_BUFFER_FLAG_IS_SET (buffer, GST_BUFFER_FLAG_DISCONT)) {
    gst_adapter_clear (visual->adapter);
  }

  GST_DEBUG_OBJECT (visual,
      "Input buffer has %d samples, time=%" G_GUINT64_FORMAT,
      GST_BUFFER_SIZE (buffer) / visual->bps, GST_BUFFER_TIMESTAMP (buffer));

  gst_adapter_push (visual->adapter, buffer);

  while (TRUE) {
    gboolean need_skip;
    guint64 dist, timestamp;

    GST_DEBUG_OBJECT (visual, "processing buffer");

    avail = gst_adapter_available (visual->adapter);
    GST_DEBUG_OBJECT (visual, "avail now %u", avail);

    /* we need at least VISUAL_SAMPLES samples */
    if (avail < VISUAL_SAMPLES * visual->bps)
      break;

    /* we need at least enough samples to make one frame */
    if (avail < visual->spf * visual->bps)
      break;

    /* get timestamp of the current adapter byte */
    timestamp = gst_adapter_prev_timestamp (visual->adapter, &dist);
    if (GST_CLOCK_TIME_IS_VALID (timestamp)) {
      /* convert bytes to time */
      dist /= visual->bps;
      timestamp += gst_util_uint64_scale_int (dist, GST_SECOND, visual->rate);
    }

    if (timestamp != -1) {
      gint64 qostime;

      /* QoS is done on running time */
      qostime = gst_segment_to_running_time (&visual->segment, GST_FORMAT_TIME,
          timestamp);
      qostime += visual->duration;

      GST_OBJECT_LOCK (visual);
      /* check for QoS, don't compute buffers that are known to be late */
      need_skip = visual->earliest_time != -1 &&
          qostime <= visual->earliest_time;
      GST_OBJECT_UNLOCK (visual);

      if (need_skip) {
        GST_WARNING_OBJECT (visual,
            "QoS: skip ts: %" GST_TIME_FORMAT ", earliest: %" GST_TIME_FORMAT,
            GST_TIME_ARGS (qostime), GST_TIME_ARGS (visual->earliest_time));
        goto skip;
      }
    }

    /* alloc a buffer if we don't have one yet, this happens
     * when we pushed a buffer in this while loop before */
    if (outbuf == NULL) {
      ret = get_buffer (visual, &outbuf);
      if (ret != GST_FLOW_OK) {
        goto beach;
      }
    }

    /* render libvisual plugin to our target */
    gst_gl_display_use_fbo_v2 (visual->display,
        visual->width, visual->height, visual->fbo, visual->depthbuffer,
        visual->midtexture, (GLCB_V2) render_frame, (gpointer *) visual);

    /* gst video is top-down whereas opengl plan is bottom up */
    gst_gl_display_use_fbo (visual->display,
        visual->width, visual->height, visual->fbo, visual->depthbuffer,
        outbuf->texture, (GLCB) bottom_up_to_top_down,
        visual->width, visual->height, visual->midtexture,
        0, visual->width, 0, visual->height, GST_GL_DISPLAY_PROJECTION_ORTHO2D,
        (gpointer *) visual);

    GST_BUFFER_TIMESTAMP (outbuf) = timestamp;
    GST_BUFFER_DURATION (outbuf) = visual->duration;

    ret = gst_pad_push (visual->srcpad, GST_BUFFER (outbuf));
    outbuf = NULL;

  skip:
    GST_DEBUG_OBJECT (visual, "finished frame, flushing %u samples from input",
        visual->spf);

    /* Flush out the number of samples per frame */
    gst_adapter_flush (visual->adapter, visual->spf * visual->bps);

    /* quit the loop if something was wrong */
    if (ret != GST_FLOW_OK)
      break;
  }

beach:

  if (outbuf != NULL)
    gst_gl_buffer_unref (outbuf);

  gst_object_unref (visual);

  return ret;
}

static GstStateChangeReturn
gst_visual_gl_change_state (GstElement * element, GstStateChange transition)
{
  GstVisualGL *visual = GST_VISUAL_GL (element);
  GstStateChangeReturn ret;

  switch (transition) {
    case GST_STATE_CHANGE_NULL_TO_READY:
      break;
    case GST_STATE_CHANGE_READY_TO_PAUSED:
    {
      GstElement *parent = GST_ELEMENT (gst_element_get_parent (visual));
      GstStructure *structure = NULL;
      GstQuery *query = NULL;
      gboolean isPerformed = FALSE;
      gchar *name;

      if (!parent) {
        GST_ELEMENT_ERROR (visual, CORE, STATE_CHANGE, (NULL),
            ("A parent bin is required"));
        return FALSE;
      }

      name = gst_element_get_name (visual);
      structure = gst_structure_new (name, NULL);
      query = gst_query_new_application (GST_QUERY_CUSTOM, structure);
      g_free (name);

      isPerformed = gst_element_query (parent, query);

      if (isPerformed) {
        const GValue *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 */
          visual->display =
              gst_object_ref (GST_GL_DISPLAY (g_value_get_pointer (id_value)));
        else {
          /* this gl filter is a sink in terms of the gl chain */
          visual->display = gst_gl_display_new ();
          gst_gl_display_create_context (visual->display, 0);
          //TODO visual->external_gl_context);
        }

        gst_visual_gl_reset (visual);

        visual->actor =
            visual_actor_new (GST_VISUAL_GL_GET_CLASS (visual)->plugin->info->
            plugname);
        visual->video = visual_video_new ();
        visual->audio = visual_audio_new ();

        if (!visual->actor || !visual->video)
          goto actor_setup_failed;

        gst_gl_display_thread_add (visual->display,
            (GstGLDisplayThreadFunc) actor_setup, visual);

        if (visual->actor_setup_result != 0)
          goto actor_setup_failed;
        else
          visual_actor_set_video (visual->actor, visual->video);
      }

      gst_query_unref (query);
      gst_object_unref (GST_OBJECT (parent));

      if (!isPerformed)
        return GST_STATE_CHANGE_FAILURE;
    }
      break;
    case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
      break;
    default:
      break;
  }

  ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);

  switch (transition) {
    case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
      break;
    case GST_STATE_CHANGE_PAUSED_TO_READY:
    {
      if (visual->fbo) {
        gst_gl_display_del_fbo (visual->display, visual->fbo,
            visual->depthbuffer);
        visual->fbo = 0;
        visual->depthbuffer = 0;
      }
      if (visual->midtexture) {
        gst_gl_display_del_texture (visual->display, visual->midtexture,
            visual->width, visual->height);
        visual->midtexture = 0;
      }
      if (visual->display) {
        gst_object_unref (visual->display);
        visual->display = NULL;
      }

      gst_visual_gl_clear_actors (visual);
    }
      break;
    case GST_STATE_CHANGE_READY_TO_NULL:
      break;
    default:
      break;
  }

  return ret;

  /* ERRORS */
actor_setup_failed:
  {
    GST_ELEMENT_ERROR (visual, LIBRARY, INIT, (NULL),
        ("could not set up actor"));
    gst_visual_gl_clear_actors (visual);
    return GST_STATE_CHANGE_FAILURE;
  }
}

static void
make_valid_name (char *name)
{
  /*
   * Replace invalid chars with _ in the type name
   */
  static const gchar extra_chars[] = "-_+";
  gchar *p = name;

  for (; *p; p++) {
    int valid = ((p[0] >= 'A' && p[0] <= 'Z') ||
        (p[0] >= 'a' && p[0] <= 'z') ||
        (p[0] >= '0' && p[0] <= '9') || strchr (extra_chars, p[0]));
    if (!valid)
      *p = '_';
  }
}

static gboolean
gst_visual_gl_actor_plugin_is_gl (VisObject * plugin, const gchar * name)
{
  gboolean is_gl;
  gint depth;

  depth = VISUAL_ACTOR_PLUGIN (plugin)->vidoptions.depth;
  is_gl = (depth & VISUAL_VIDEO_DEPTH_GL) != 0;

  if (!is_gl) {
    GST_DEBUG ("plugin %s is not a GL plugin (%d), ignoring", name, depth);
  } else {
    GST_DEBUG ("plugin %s is a GL plugin (%d), registering", name, depth);
  }

  return is_gl;
}

static gboolean
plugin_init (GstPlugin * plugin)
{
  guint i, count;
  VisList *list;

  GST_DEBUG_CATEGORY_INIT (libvisual_debug, "libvisual", 0,
      "libvisual audio visualisations");

#ifdef LIBVISUAL_PLUGINSBASEDIR
  gst_plugin_add_dependency_simple (plugin, "HOME/.libvisual/actor",
      LIBVISUAL_PLUGINSBASEDIR "/actor", NULL, GST_PLUGIN_DEPENDENCY_FLAG_NONE);
#endif

  visual_log_set_verboseness (VISUAL_LOG_VERBOSENESS_LOW);
  visual_log_set_info_handler (libvisual_log_handler, (void *) GST_LEVEL_INFO);
  visual_log_set_warning_handler (libvisual_log_handler,
      (void *) GST_LEVEL_WARNING);
  visual_log_set_critical_handler (libvisual_log_handler,
      (void *) GST_LEVEL_ERROR);
  visual_log_set_error_handler (libvisual_log_handler,
      (void *) GST_LEVEL_ERROR);

  if (!visual_is_initialized ())
    if (visual_init (NULL, NULL) != 0)
      return FALSE;

  list = visual_actor_get_list ();

  count = visual_collection_size (VISUAL_COLLECTION (list));

  for (i = 0; i < count; i++) {
    VisPluginRef *ref = visual_list_get (list, i);
    VisPluginData *visplugin = NULL;
    gboolean skip = FALSE;
    GType type;
    gchar *name;
    GTypeInfo info = {
      sizeof (GstVisualGLClass),
      NULL,
      NULL,
      gst_visual_gl_class_init,
      NULL,
      ref,
      sizeof (GstVisualGL),
      0,
      NULL
    };

    visplugin = visual_plugin_load (ref);

    if (ref->info->plugname == NULL)
      continue;

    /* Blacklist some plugins */
    if (strcmp (ref->info->plugname, "gstreamer") == 0 ||
        strcmp (ref->info->plugname, "gdkpixbuf") == 0) {
      skip = TRUE;
    } else {
      /* only register plugins that support GL */
      skip = !(gst_visual_gl_actor_plugin_is_gl (visplugin->info->plugin,
              visplugin->info->plugname));
    }

    visual_plugin_unload (visplugin);

    if (!skip) {
      name = g_strdup_printf ("GstVisualGL%s", ref->info->plugname);
      make_valid_name (name);
      type = g_type_register_static (GST_TYPE_VISUAL_GL, name, &info, 0);
      g_free (name);

      name = g_strdup_printf ("libvisual_gl_%s", ref->info->plugname);
      make_valid_name (name);
      if (!gst_element_register (plugin, name, GST_RANK_NONE, type)) {
        g_free (name);
        return FALSE;
      }
      g_free (name);
    }
  }

  return TRUE;
}

GST_PLUGIN_DEFINE (GST_VERSION_MAJOR,
    GST_VERSION_MINOR,
    "libvisual-gl",
    "libvisual-gl visualization plugins",
    plugin_init, VERSION, "LGPL", GST_PACKAGE_NAME, GST_PACKAGE_ORIGIN)