/* gstmonoscope.c: implementation of monoscope drawing element
 * Copyright (C) <2002> Richard Boulton <richard@tartarus.org>
 * Copyright (C) <2006> Tim-Philipp Müller <tim centricular net>
 * Copyright (C) <2006> Wim Taymans <wim at fluendo dot 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-monoscope
 * @see_also: goom
 *
 * Monoscope is an audio visualisation element. It creates a coloured
 * curve of the audio signal like on an oscilloscope.
 *
 * <refsect2>
 * <title>Example launch line</title>
 * |[
 * gst-launch-1.0 -v audiotestsrc ! audioconvert ! monoscope ! videoconvert ! ximagesink
 * ]|
 * </refsect2>
 */

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

#include <gst/video/video.h>
#include <gst/audio/audio.h>
#include <string.h>
#include "gstmonoscope.h"
#include "monoscope.h"

GST_DEBUG_CATEGORY_STATIC (monoscope_debug);
#define GST_CAT_DEFAULT monoscope_debug

#if G_BYTE_ORDER == G_BIG_ENDIAN
#define RGB_ORDER "xRGB"
#else
#define RGB_ORDER "BGRx"
#endif

static GstStaticPadTemplate src_template = GST_STATIC_PAD_TEMPLATE ("src",
    GST_PAD_SRC,
    GST_PAD_ALWAYS,
    GST_STATIC_CAPS ("video/x-raw, "
        "format = (string) " RGB_ORDER ", "
        "width = " G_STRINGIFY (scope_width) ", "
        "height = " G_STRINGIFY (scope_height) ", "
        "framerate = " GST_VIDEO_FPS_RANGE)
    );

static GstStaticPadTemplate sink_template = GST_STATIC_PAD_TEMPLATE ("sink",
    GST_PAD_SINK,
    GST_PAD_ALWAYS,
    GST_STATIC_CAPS ("audio/x-raw, "
        "format = (string) " GST_AUDIO_NE (S16) ", "
        "rate = (int) [ 8000, 96000 ], "
        "channels = (int) 1, " "layout = (string) interleaved")
    );


#define gst_monoscope_parent_class parent_class
G_DEFINE_TYPE (GstMonoscope, gst_monoscope, GST_TYPE_ELEMENT);

static void gst_monoscope_finalize (GObject * object);
static GstFlowReturn gst_monoscope_chain (GstPad * pad, GstObject * parent,
    GstBuffer * buf);
static gboolean gst_monoscope_src_setcaps (GstMonoscope * mono, GstCaps * caps);
static gboolean gst_monoscope_sink_setcaps (GstMonoscope * mono,
    GstCaps * caps);
static void gst_monoscope_reset (GstMonoscope * monoscope);
static gboolean gst_monoscope_sink_event (GstPad * pad, GstObject * parent,
    GstEvent * event);
static gboolean gst_monoscope_src_event (GstPad * pad, GstObject * parent,
    GstEvent * event);
static GstStateChangeReturn gst_monoscope_change_state (GstElement * element,
    GstStateChange transition);

static void
gst_monoscope_class_init (GstMonoscopeClass * klass)
{
  GObjectClass *gobject_class;
  GstElementClass *gstelement_class;

  gobject_class = (GObjectClass *) klass;
  gstelement_class = (GstElementClass *) klass;

  gobject_class->finalize = gst_monoscope_finalize;

  gstelement_class->change_state =
      GST_DEBUG_FUNCPTR (gst_monoscope_change_state);

  gst_element_class_add_static_pad_template (gstelement_class, &src_template);
  gst_element_class_add_static_pad_template (gstelement_class, &sink_template);
  gst_element_class_set_static_metadata (gstelement_class, "Monoscope",
      "Visualization",
      "Displays a highly stabilised waveform of audio input",
      "Richard Boulton <richard@tartarus.org>");
}

static void
gst_monoscope_init (GstMonoscope * monoscope)
{
  monoscope->sinkpad =
      gst_pad_new_from_static_template (&sink_template, "sink");
  gst_pad_set_chain_function (monoscope->sinkpad,
      GST_DEBUG_FUNCPTR (gst_monoscope_chain));
  gst_pad_set_event_function (monoscope->sinkpad,
      GST_DEBUG_FUNCPTR (gst_monoscope_sink_event));
  gst_element_add_pad (GST_ELEMENT (monoscope), monoscope->sinkpad);

  monoscope->srcpad = gst_pad_new_from_static_template (&src_template, "src");
  gst_pad_set_event_function (monoscope->srcpad,
      GST_DEBUG_FUNCPTR (gst_monoscope_src_event));
  gst_element_add_pad (GST_ELEMENT (monoscope), monoscope->srcpad);

  monoscope->adapter = gst_adapter_new ();
  monoscope->next_ts = GST_CLOCK_TIME_NONE;
  monoscope->bps = sizeof (gint16);

  /* reset the initial video state */
  monoscope->width = scope_width;
  monoscope->height = scope_height;
  monoscope->fps_num = 25;      /* desired frame rate */
  monoscope->fps_denom = 1;
  monoscope->visstate = NULL;

  /* reset the initial audio state */
  monoscope->rate = GST_AUDIO_DEF_RATE;
}

static void
gst_monoscope_finalize (GObject * object)
{
  GstMonoscope *monoscope = GST_MONOSCOPE (object);

  if (monoscope->visstate)
    monoscope_close (monoscope->visstate);

  g_object_unref (monoscope->adapter);

  G_OBJECT_CLASS (parent_class)->finalize (object);
}

static void
gst_monoscope_reset (GstMonoscope * monoscope)
{
  monoscope->next_ts = GST_CLOCK_TIME_NONE;

  gst_adapter_clear (monoscope->adapter);
  gst_segment_init (&monoscope->segment, GST_FORMAT_UNDEFINED);
  monoscope->segment_pending = FALSE;

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

static gboolean
gst_monoscope_sink_setcaps (GstMonoscope * monoscope, GstCaps * caps)
{
  GstStructure *structure;

  structure = gst_caps_get_structure (caps, 0);

  gst_structure_get_int (structure, "rate", &monoscope->rate);

  GST_DEBUG_OBJECT (monoscope, "sample rate = %d", monoscope->rate);
  return TRUE;
}

static gboolean
gst_monoscope_src_setcaps (GstMonoscope * monoscope, GstCaps * caps)
{
  GstStructure *structure;
  gboolean res;

  structure = gst_caps_get_structure (caps, 0);

  gst_structure_get_int (structure, "width", &monoscope->width);
  gst_structure_get_int (structure, "height", &monoscope->height);
  gst_structure_get_fraction (structure, "framerate", &monoscope->fps_num,
      &monoscope->fps_denom);

  monoscope->outsize = monoscope->width * monoscope->height * 4;
  monoscope->frame_duration = gst_util_uint64_scale_int (GST_SECOND,
      monoscope->fps_denom, monoscope->fps_num);
  monoscope->spf =
      gst_util_uint64_scale_int (monoscope->rate, monoscope->fps_denom,
      monoscope->fps_num);

  GST_DEBUG_OBJECT (monoscope, "dimension %dx%d, framerate %d/%d, spf %d",
      monoscope->width, monoscope->height, monoscope->fps_num,
      monoscope->fps_denom, monoscope->spf);

  if (monoscope->visstate) {
    monoscope_close (monoscope->visstate);
    monoscope->visstate = NULL;
  }

  monoscope->visstate = monoscope_init (monoscope->width, monoscope->height);

  res = gst_pad_set_caps (monoscope->srcpad, caps);

  return res && (monoscope->visstate != NULL);
}

static gboolean
gst_monoscope_src_negotiate (GstMonoscope * monoscope)
{
  GstCaps *othercaps, *target;
  GstStructure *structure;
  GstCaps *templ;
  GstQuery *query;
  GstBufferPool *pool;
  GstStructure *config;
  guint size, min, max;

  templ = gst_pad_get_pad_template_caps (monoscope->srcpad);

  GST_DEBUG_OBJECT (monoscope, "performing negotiation");

  /* see what the peer can do */
  othercaps = gst_pad_peer_query_caps (monoscope->srcpad, NULL);
  if (othercaps) {
    target = gst_caps_intersect (othercaps, templ);
    gst_caps_unref (othercaps);
    gst_caps_unref (templ);

    if (gst_caps_is_empty (target))
      goto no_format;

    target = gst_caps_truncate (target);
  } else {
    target = templ;
  }

  target = gst_caps_make_writable (target);
  structure = gst_caps_get_structure (target, 0);
  gst_structure_fixate_field_nearest_int (structure, "width", 320);
  gst_structure_fixate_field_nearest_int (structure, "height", 240);
  gst_structure_fixate_field_nearest_fraction (structure, "framerate", 25, 1);

  gst_monoscope_src_setcaps (monoscope, target);

  /* try to get a bufferpool now */
  /* find a pool for the negotiated caps now */
  query = gst_query_new_allocation (target, TRUE);

  if (!gst_pad_peer_query (monoscope->srcpad, query)) {
  }

  if (gst_query_get_n_allocation_pools (query) > 0) {
    /* we got configuration from our peer, parse them */
    gst_query_parse_nth_allocation_pool (query, 0, &pool, &size, &min, &max);
  } else {
    pool = NULL;
    size = monoscope->outsize;
    min = max = 0;
  }

  if (pool == NULL) {
    /* we did not get a pool, make one ourselves then */
    pool = gst_buffer_pool_new ();
  }

  config = gst_buffer_pool_get_config (pool);
  gst_buffer_pool_config_set_params (config, target, size, min, max);
  gst_buffer_pool_set_config (pool, config);

  if (monoscope->pool) {
    gst_buffer_pool_set_active (monoscope->pool, TRUE);
    gst_object_unref (monoscope->pool);
  }
  monoscope->pool = pool;

  /* and activate */
  gst_buffer_pool_set_active (pool, TRUE);

  gst_query_unref (query);
  gst_caps_unref (target);

  return TRUE;

no_format:
  {
    gst_caps_unref (target);
    return FALSE;
  }
}

/* make sure we are negotiated */
static GstFlowReturn
ensure_negotiated (GstMonoscope * monoscope)
{
  gboolean reconfigure;

  reconfigure = gst_pad_check_reconfigure (monoscope->srcpad);

  /* we don't know an output format yet, pick one */
  if (reconfigure || !gst_pad_has_current_caps (monoscope->srcpad)) {
    if (!gst_monoscope_src_negotiate (monoscope)) {
      gst_pad_mark_reconfigure (monoscope->srcpad);
      if (GST_PAD_IS_FLUSHING (monoscope->srcpad))
        return GST_FLOW_FLUSHING;
      else
        return GST_FLOW_NOT_NEGOTIATED;
    }
  }
  return GST_FLOW_OK;
}

static GstFlowReturn
gst_monoscope_chain (GstPad * pad, GstObject * parent, GstBuffer * inbuf)
{
  GstFlowReturn flow_ret = GST_FLOW_OK;
  GstMonoscope *monoscope;

  monoscope = GST_MONOSCOPE (parent);

  if (monoscope->rate == 0) {
    gst_buffer_unref (inbuf);
    flow_ret = GST_FLOW_NOT_NEGOTIATED;
    goto out;
  }

  /* Make sure have an output format */
  flow_ret = ensure_negotiated (monoscope);
  if (flow_ret != GST_FLOW_OK) {
    gst_buffer_unref (inbuf);
    goto out;
  }

  if (monoscope->segment_pending) {
    gst_pad_push_event (monoscope->srcpad,
        gst_event_new_segment (&monoscope->segment));
    monoscope->segment_pending = FALSE;
  }

  /* don't try to combine samples from discont buffer */
  if (GST_BUFFER_FLAG_IS_SET (inbuf, GST_BUFFER_FLAG_DISCONT)) {
    gst_adapter_clear (monoscope->adapter);
    monoscope->next_ts = GST_CLOCK_TIME_NONE;
  }

  /* Match timestamps from the incoming audio */
  if (GST_BUFFER_TIMESTAMP (inbuf) != GST_CLOCK_TIME_NONE)
    monoscope->next_ts = GST_BUFFER_TIMESTAMP (inbuf);

  GST_LOG_OBJECT (monoscope,
      "in buffer has %" G_GSIZE_FORMAT " samples, ts=%" GST_TIME_FORMAT,
      gst_buffer_get_size (inbuf) / monoscope->bps,
      GST_TIME_ARGS (GST_BUFFER_TIMESTAMP (inbuf)));

  gst_adapter_push (monoscope->adapter, inbuf);
  inbuf = NULL;

  /* Collect samples until we have enough for an output frame */
  while (flow_ret == GST_FLOW_OK) {
    gint16 *samples;
    GstBuffer *outbuf = NULL;
    guint32 *pixels, avail, bytesperframe;

    avail = gst_adapter_available (monoscope->adapter);
    GST_LOG_OBJECT (monoscope, "bytes avail now %u", avail);

    bytesperframe = monoscope->spf * monoscope->bps;
    if (avail < bytesperframe)
      break;

    /* FIXME: something is wrong with QoS, we are skipping way too much
     * stuff even with very low CPU loads */
#if 0
    if (monoscope->next_ts != -1) {
      gboolean need_skip;
      gint64 qostime;

      qostime = gst_segment_to_running_time (&monoscope->segment,
          GST_FORMAT_TIME, monoscope->next_ts);

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

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

    samples = (gint16 *) gst_adapter_map (monoscope->adapter, bytesperframe);

    if (monoscope->spf < convolver_big) {
      gint16 in_data[convolver_big], i;
      gdouble scale = (gdouble) monoscope->spf / (gdouble) convolver_big;

      for (i = 0; i < convolver_big; ++i) {
        gdouble off = (gdouble) i * scale;
        in_data[i] = samples[MIN ((guint) off, monoscope->spf)];
      }
      pixels = monoscope_update (monoscope->visstate, in_data);
    } else {
      /* not really correct, but looks much prettier */
      pixels = monoscope_update (monoscope->visstate, samples);
    }

    GST_LOG_OBJECT (monoscope, "allocating output buffer");
    flow_ret = gst_buffer_pool_acquire_buffer (monoscope->pool, &outbuf, NULL);
    if (flow_ret != GST_FLOW_OK) {
      gst_adapter_unmap (monoscope->adapter);
      goto out;
    }

    gst_buffer_fill (outbuf, 0, pixels, monoscope->outsize);

    GST_BUFFER_TIMESTAMP (outbuf) = monoscope->next_ts;
    GST_BUFFER_DURATION (outbuf) = monoscope->frame_duration;

    flow_ret = gst_pad_push (monoscope->srcpad, outbuf);

#if 0
  skip:
#endif

    if (GST_CLOCK_TIME_IS_VALID (monoscope->next_ts))
      monoscope->next_ts += monoscope->frame_duration;

    gst_adapter_flush (monoscope->adapter, bytesperframe);
  }

out:

  return flow_ret;
}

static gboolean
gst_monoscope_sink_event (GstPad * pad, GstObject * parent, GstEvent * event)
{
  GstMonoscope *monoscope;
  gboolean res;

  monoscope = GST_MONOSCOPE (parent);

  switch (GST_EVENT_TYPE (event)) {
    case GST_EVENT_FLUSH_START:
      res = gst_pad_push_event (monoscope->srcpad, event);
      break;
    case GST_EVENT_FLUSH_STOP:
      gst_monoscope_reset (monoscope);
      res = gst_pad_push_event (monoscope->srcpad, event);
      break;
    case GST_EVENT_SEGMENT:
    {
      /* 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_copy_segment (event, &monoscope->segment);

      /* We forward the event from the chain function after caps are
       * negotiated. Otherwise we would potentially break the event order and
       * send the segment event before the caps event */
      monoscope->segment_pending = TRUE;
      gst_event_unref (event);
      res = TRUE;
      break;
    }
    case GST_EVENT_CAPS:
    {
      GstCaps *caps;

      gst_event_parse_caps (event, &caps);
      gst_monoscope_sink_setcaps (monoscope, caps);
      gst_event_unref (event);
      res = TRUE;
      break;
    }
    default:
      res = gst_pad_push_event (monoscope->srcpad, event);
      break;
  }

  return res;
}

static gboolean
gst_monoscope_src_event (GstPad * pad, GstObject * parent, GstEvent * event)
{
  GstMonoscope *monoscope;
  gboolean res;

  monoscope = GST_MONOSCOPE (parent);

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

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

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

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

  return res;
}

static GstStateChangeReturn
gst_monoscope_change_state (GstElement * element, GstStateChange transition)
{
  GstMonoscope *monoscope = GST_MONOSCOPE (element);
  GstStateChangeReturn ret;

  switch (transition) {
    case GST_STATE_CHANGE_NULL_TO_READY:
      break;
    case GST_STATE_CHANGE_READY_TO_PAUSED:
      gst_monoscope_reset (monoscope);
      break;
    default:
      break;
  }

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

  switch (transition) {
    case GST_STATE_CHANGE_PAUSED_TO_READY:
      if (monoscope->pool) {
        gst_buffer_pool_set_active (monoscope->pool, FALSE);
        gst_object_replace ((GstObject **) & monoscope->pool, NULL);
      }
      break;
    case GST_STATE_CHANGE_READY_TO_NULL:
      break;
    default:
      break;
  }

  return ret;
}

static gboolean
plugin_init (GstPlugin * plugin)
{
  GST_DEBUG_CATEGORY_INIT (monoscope_debug, "monoscope", 0,
      "monoscope element");

  return gst_element_register (plugin, "monoscope",
      GST_RANK_NONE, GST_TYPE_MONOSCOPE);
}

GST_PLUGIN_DEFINE (GST_VERSION_MAJOR,
    GST_VERSION_MINOR,
    monoscope,
    "Monoscope visualization",
    plugin_init, VERSION, "LGPL", GST_PACKAGE_NAME, GST_PACKAGE_ORIGIN);