// subtitleeditor -- a tool to create or edit subtitle
//
// https://kitone.github.io/subtitleeditor/
// https://github.com/kitone/subtitleeditor/
//
// Copyright @ 2005-2018, kitone
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 3 of the License, or
// (at your option) any later version.
//
// This program 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 General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.

#include <gstreamermm.h>
#include <gtkmm.h>
#include <keyframes.h>
#include <utility.h>
#include <iomanip>
#include <iostream>
#include "mediadecoder.h"

class KeyframesGenerator : public Gtk::Dialog, public MediaDecoder {
 public:
  KeyframesGenerator(const Glib::ustring &uri,
                     Glib::RefPtr<KeyFrames> &keyframes)
      : Gtk::Dialog(_("Generate Keyframes"), true), MediaDecoder(1000) {
    set_border_width(12);
    set_default_size(300, -1);
    get_vbox()->pack_start(m_progressbar, false, false);
    add_button(Gtk::Stock::CANCEL, Gtk::RESPONSE_CANCEL);
    m_progressbar.set_text(_("Waiting..."));
    show_all();

    try {
      create_pipeline(uri);

      if (run() == Gtk::RESPONSE_OK) {
        keyframes = Glib::RefPtr<KeyFrames>(new KeyFrames);
        keyframes->insert(keyframes->end(), m_values.begin(), m_values.end());
        keyframes->set_video_uri(uri);
      }
    } catch (const std::runtime_error &ex) {
      std::cerr << ex.what() << std::endl;
    }
  }

  // Check buffer and try to catch keyframes.
  void on_video_identity_handoff(const Glib::RefPtr<Gst::Buffer> &buf,
                                 const Glib::RefPtr<Gst::Pad> &) {
    // FIXME: http://bugzilla.gnome.org/show_bug.cgi?id=590923
    // if(!buf->flag_is_set(GST_BUFFER_FLAG_DELTA_UNIT))//Gst::BUFFER_FLAG_DELTA_UNIT))
    if (!GST_BUFFER_FLAG_IS_SET(buf->gobj(), GST_BUFFER_FLAG_DELTA_UNIT)) {
      // FIXME: gstreamer 1.0
      // long pos = buf->get_timestamp() / GST_MSECOND;
      long pos = buf->get_pts() / GST_MSECOND;
      m_values.push_back(pos);
    }
  }

  // Create video bin
  Glib::RefPtr<Gst::Element> create_element(
      const Glib::ustring &structure_name) {
    try {
      // We only need and want create the video sink
      if (structure_name.find("video") == Glib::ustring::npos)
        return Glib::RefPtr<Gst::Element>(NULL);

      Glib::RefPtr<Gst::FakeSink> fakesink = Gst::FakeSink::create("fakesink");
      fakesink->set_sync(false);
      fakesink->property_silent() = true;
      fakesink->property_signal_handoffs() = true;
      fakesink->signal_handoff().connect(
          sigc::mem_fun(*this, &KeyframesGenerator::on_video_identity_handoff));

      // Set the new sink tp READY as well
      Gst::StateChangeReturn retst = fakesink->set_state(Gst::STATE_READY);
      if (retst == Gst::STATE_CHANGE_FAILURE)
        std::cerr << "Could not change state of new sink: " << retst
                  << std::endl;

      return fakesink;
    } catch (std::runtime_error &ex) {
      std::cerr << "create_element runtime_error: " << ex.what() << std::endl;
    }
    return Glib::RefPtr<Gst::Element>(NULL);
  }

  // Update the progress bar
  bool on_timeout() {
    if (!m_pipeline)
      return false;

    Gst::Format fmt = Gst::FORMAT_TIME;
    gint64 pos = 0, len = 0;
    if (m_pipeline->query_position(fmt, pos) &&
        m_pipeline->query_duration(fmt, len)) {
      double percent = static_cast<double>(pos) / static_cast<double>(len);

      percent = CLAMP(percent, 0.0, 1.0);

      m_progressbar.set_fraction(percent);
      m_progressbar.set_text(time_to_string(pos) + " / " + time_to_string(len));
      m_duration = len;

      return pos != len;
    } else {
      m_progressbar.set_text(_("Waiting..."));
    }
    return true;
  }

  void on_work_finished() {
    response(Gtk::RESPONSE_OK);
  }

  void on_work_cancel() {
    response(Gtk::RESPONSE_CANCEL);
  }

 protected:
  Gtk::ProgressBar m_progressbar;

  std::list<long> m_values;
  guint64 m_duration;
};

Glib::RefPtr<KeyFrames> generate_keyframes_from_file(const Glib::ustring &uri) {
  Glib::RefPtr<KeyFrames> kf;
  KeyframesGenerator ui(uri, kf);
  return kf;
}
