/*
 * vim: set sts=2 sw=2 et :
 *
 * License: LGPL-2.1+
 * Copyright (c) 2014 Nirbheek Chauhan <nirbheek@centricular.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 "local-play.h"

static void
pad_has_video_caps (TranscodeServerCtx *ctx,
                    GstPad             *decodebin_pad)
{
  GstPad *sink_pad;
  GstElement *bin;
  GstElement *videoconv, *videoscale, *videosink;

  bin = gst_bin_new (NULL);
  videoconv = gst_element_factory_make ("videoconvert", "videoconv");
  videoscale = gst_element_factory_make ("videoscale", "videoscale");
  videosink = gst_element_factory_make ("autovideosink", "videosink");

  gst_bin_add_many (GST_BIN (bin), videoconv, videoscale, videosink, NULL);
  gst_element_link_many (videoconv, videoscale, videosink, NULL);

  sink_pad = gst_element_get_static_pad (videoconv, "sink");
  gst_element_add_pad (bin, gst_ghost_pad_new ("sink", sink_pad));
  gst_object_unref (sink_pad);

  gst_bin_add (GST_BIN (ctx->pipeline), bin);

  sink_pad = gst_element_get_static_pad (bin, "sink");
  if (gst_pad_link (decodebin_pad, sink_pad) != GST_PAD_LINK_OK) {
    g_critical ("ERROR: Unable to link video pads");
    soup_message_set_status (ctx->msg, SOUP_STATUS_INTERNAL_SERVER_ERROR);
    goto out;
  }

  /* Since these elements have been added to the pipeline after the state was
   * changed from GST_STATE_NULL, they have to be moved to PAUSED manually */
  gst_element_set_state (bin, GST_STATE_PAUSED);
out:
  gst_object_unref (sink_pad);
  return;
}

static void
pad_has_audio_caps (TranscodeServerCtx *ctx,
                    GstPad             *decodebin_pad)
{
  GstPad *sink_pad;
  GstElement *bin;
  GstElement *audioconv, *audioresample, *audiosink;

  bin = gst_bin_new (NULL);
  audioconv = gst_element_factory_make ("audioconvert", "audioconv");
  audioresample = gst_element_factory_make ("audioresample", "audioresample");
  audiosink = gst_element_factory_make ("autoaudiosink", "audiosink");

  gst_bin_add_many (GST_BIN (bin), audioconv, audioresample, audiosink, NULL);
  gst_element_link_many (audioconv, audioresample, audiosink, NULL);

  sink_pad = gst_element_get_static_pad (audioconv, "sink");
  gst_element_add_pad (bin, gst_ghost_pad_new ("sink", sink_pad));
  gst_object_unref (sink_pad);

  gst_bin_add (GST_BIN (ctx->pipeline), bin);

  sink_pad = gst_element_get_static_pad (bin, "sink");
  if (gst_pad_link (decodebin_pad, sink_pad) != GST_PAD_LINK_OK) {
    g_critical ("ERROR: Unable to link video pads");
    soup_message_set_status (ctx->msg, SOUP_STATUS_INTERNAL_SERVER_ERROR);
    goto out;
  }

  /* Since these elements have been added to the pipeline after the state was
   * changed from GST_STATE_NULL, they have to be moved to PAUSED manually */
  gst_element_set_state (bin, GST_STATE_PAUSED);
out:
  gst_object_unref (sink_pad);
  return;
}

static gboolean
structure_printf (GQuark field_id,
                  const GValue *value,
                  gpointer user_data)
{
  char *char_value;

  char_value = g_strdup_value_contents (value);
  g_print ("%s = %s\n", g_quark_to_string (field_id), char_value);
  g_free (char_value);
  return TRUE;
}

static void
decodebin_pad_added (GstElement *decodebin,
                     GstPad     *src_pad,
                     gpointer    user_data)
{
  GstCaps *pad_caps;
  GstStructure *structure;
  TranscodeServerCtx *ctx = user_data;

  if (!gst_pad_has_current_caps (src_pad)) {
    g_critical ("Decodebin pad doesn't have current caps");
    soup_message_set_status (ctx->msg, SOUP_STATUS_INTERNAL_SERVER_ERROR);
    return;
  }

  pad_caps = gst_pad_get_current_caps (src_pad);
  structure = gst_caps_get_structure (pad_caps, 0);
  gst_structure_foreach (structure, structure_printf, NULL);

  if (gst_structure_has_name (structure, "audio/x-raw"))
    pad_has_audio_caps (ctx, src_pad);
  else if (gst_structure_has_name (structure, "video/x-raw"))
    pad_has_video_caps (ctx, src_pad);
  else
    g_critical ("Found unsupported caps: %s",
                gst_structure_get_name (structure));

  gst_caps_unref (pad_caps);
}

void
stp_play_from_msg (TranscodeServerCtx *ctx)
{
  GstBus *bus;
  GstElement *src, *decodebin;

  g_debug ("Constructing pipeline\n");
  src = gst_element_factory_make ("appsrc", "src");
  g_object_set (src, "is-live", TRUE,
                "stream-type", 0, NULL);
  ctx->appsrc = src;

  decodebin = gst_element_factory_make ("decodebin", "decodebin");
  gst_bin_add_many (GST_BIN (ctx->pipeline), src, decodebin, NULL);
  gst_element_link (src, decodebin);

  g_signal_connect (decodebin, "pad-added",
                    G_CALLBACK (decodebin_pad_added), ctx);

  bus = gst_pipeline_get_bus (GST_PIPELINE (ctx->pipeline));
  gst_bus_add_signal_watch (bus);
  g_signal_connect (bus, "message", G_CALLBACK (stp_on_gst_bus_message), ctx);
  g_object_unref (bus);
}