/* gstreamermm - a C++ wrapper for gstreamer
 *
 * Copyright 2008 The gstreamermm Development Team
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2
 * as published by the Free Software Foundation.
 *
 * 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, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

#include <gtkmm/stock.h>
#include <gtkmm/filechooserdialog.h>
#include <gstreamermm/bus.h>
#include <gstreamermm/clock.h>
#include <gstreamermm/event.h>
#include <gstreamermm/message.h>
#include <gstreamermm/query.h>
#include <iostream>
#include <sstream>
#include <iomanip>
#include "player_window.h"

PlayerWindow::PlayerWindow(const Glib::RefPtr<Gst::FileSrc>& source_element,
  const Glib::RefPtr<Gst::Pipeline>& main_pipeline)
: m_vbox(false, 5),
  m_progress_label("000:00:00.000000000 / 000:00:00.000000000"),
  m_play_button(Gtk::Stock::MEDIA_PLAY),
  m_pause_button(Gtk::Stock::MEDIA_PAUSE),
  m_stop_button(Gtk::Stock::MEDIA_STOP),
  m_rewind_button(Gtk::Stock::MEDIA_REWIND),
  m_forward_button(Gtk::Stock::MEDIA_FORWARD),
  m_open_button(Gtk::Stock::OPEN)
{
  set_title("gstreamermm Ogg Player Example");

  add(m_vbox);
  m_vbox.pack_start(m_progress_label);
  m_vbox.pack_start(m_progress_scale);
  m_vbox.pack_start(m_button_box);

  m_progress_label.set_alignment(Gtk::ALIGN_CENTER);

  m_progress_scale.set_range(0, 1);
  m_progress_scale.set_draw_value(false);
  m_progress_scale.signal_change_value().connect(
    sigc::mem_fun(*this, &PlayerWindow::on_scale_value_changed));

  m_button_box.pack_start(m_play_button);
  m_button_box.pack_start(m_pause_button);
  m_button_box.pack_start(m_stop_button);
  m_button_box.pack_start(m_rewind_button);
  m_button_box.pack_start(m_forward_button);
  m_button_box.pack_start(m_open_button);

  m_play_button.signal_clicked().connect(
    sigc::mem_fun(*this, &PlayerWindow::on_button_play ));
  m_pause_button.signal_clicked().connect(
    sigc::mem_fun(*this, &PlayerWindow::on_button_pause) );
  m_stop_button.signal_clicked().connect(
    sigc::mem_fun(*this, &PlayerWindow::on_button_stop) );
  m_rewind_button.signal_clicked().connect(
    sigc::mem_fun(*this, &PlayerWindow::on_button_rewind) );
  m_forward_button.signal_clicked().connect(
    sigc::mem_fun(*this,  &PlayerWindow::on_button_forward) );
  m_open_button.signal_clicked().connect(
    sigc::mem_fun(*this, &PlayerWindow::on_button_open) );

  // Add a bus watch to receive messages from pipeline's bus
  Glib::RefPtr<Gst::Bus> bus = main_pipeline->get_bus();
  if(bus)
  {
    m_watch_id = bus->add_watch(
      sigc::mem_fun( *this, &PlayerWindow::on_bus_message) );
  }

  m_progress_scale.set_sensitive(false);
  m_play_button.set_sensitive(false);
  m_pause_button.set_sensitive(false);
  m_stop_button.set_sensitive(false);
  m_rewind_button.set_sensitive(false);
  m_forward_button.set_sensitive(false);

  m_source_element = source_element;
  m_main_pipeline = main_pipeline;

  show_all_children();
  m_pause_button.hide();
}

// This function is used to receive asynchronous messages from main_pipeline's bus
bool PlayerWindow::on_bus_message(const Glib::RefPtr<Gst::Bus>& /* bus */, const Glib::RefPtr<Gst::Message>& message)
{
  switch(message->get_message_type())
  {
    case Gst::MESSAGE_EOS:
      //We reached the end of the file, so stop playing:
      on_button_stop();
      break;
    case Gst::MESSAGE_ERROR:
    {
      //There was an error, so stop playing, 
      //and output some information to stdout:
      Glib::RefPtr<Gst::MessageError> error_message =
        Glib::RefPtr<Gst::MessageError>::cast_dynamic(message);
      if(error_message)
      {
        Glib::Error err;
        err = error_message->parse();
        std::cerr << "Error: " << err.what() << std::endl;
      }
      else
        std::cerr << "Error." << std::endl;

      on_button_stop();
      break;
    }
    default:
    {
      //std::cout << "debug: on_bus_message: unhandled message=" << G_OBJECT_TYPE_NAME(message->gobj()) << std::endl;
    }
    break;
  }

  return true;
}

void PlayerWindow::on_button_play()
{
  m_progress_scale.set_sensitive();
  m_play_button.set_sensitive(false);
  m_pause_button.set_sensitive();
  m_stop_button.set_sensitive();
  m_rewind_button.set_sensitive();
  m_forward_button.set_sensitive();
  m_open_button.set_sensitive(false);

  m_play_button.hide();
  m_pause_button.show();

  // Call on_timeout function at a 200ms
  // interval to regularly update the position of the stream:
  m_progress_connection = Glib::signal_timeout().connect(
    sigc::mem_fun(*this, &PlayerWindow::on_timeout), 200);

  // Set the pipeline to play mode:
  m_main_pipeline->set_state(Gst::STATE_PLAYING);
}
 
void PlayerWindow::on_button_pause()
{
  m_play_button.set_sensitive();
  m_pause_button.set_sensitive(false);

  m_pause_button.hide();
  m_play_button.show();

  // Disconnect progress callback:
  m_progress_connection.disconnect();
  
  // Set the pipeline to pause mode:
  m_main_pipeline->set_state(Gst::STATE_PAUSED);
}
 
void PlayerWindow::on_button_stop()
{
  m_progress_scale.set_sensitive(false);
  m_play_button.set_sensitive();
  m_pause_button.set_sensitive(false);
  m_stop_button.set_sensitive(false);
  m_rewind_button.set_sensitive(false);
  m_forward_button.set_sensitive(false);
  m_open_button.set_sensitive();

  m_pause_button.hide();
  m_play_button.show();

  // Disconnect progress callback:
  m_progress_connection.disconnect();

  // Set the pipeline to inactive mode:
  m_main_pipeline->set_state(Gst::STATE_NULL);
  display_label_progress(0, m_duration);
  m_progress_scale.set_value(0);
}

bool PlayerWindow::on_scale_value_changed(Gtk::ScrollType /* type_not_used */, double value)
{
  const gint64 new_pos = gint64(value * m_duration);

  if(m_main_pipeline->seek(Gst::FORMAT_TIME, Gst::SEEK_FLAG_FLUSH, new_pos))
  {
    display_label_progress(new_pos, m_duration);
    return true;
  }
  else
  {
    std::cerr << "Could not seek." << std::endl;
    return false;
  }
}

void PlayerWindow::on_button_rewind()
{
  static const gint64 skip_amount = Gst::SECOND * 2;

  gint64 pos = 0;
  Gst::Format fmt = Gst::FORMAT_TIME;

  if(m_main_pipeline->query_position(fmt, pos))
  {
    const gint64 new_pos = (pos > skip_amount) ? (pos - skip_amount) : 0;

    if(m_main_pipeline->seek(Gst::FORMAT_TIME, Gst::SEEK_FLAG_FLUSH, new_pos))
    {
      display_label_progress(new_pos, m_duration);
      m_progress_scale.set_value(double(new_pos) / m_duration);
    }
    else
      std::cerr << "Could not seek." << std::endl;
  }
}

void PlayerWindow::on_button_forward()
{
  static const gint64 skip_amount = Gst::SECOND * 3;

  Gst::Format fmt = Gst::FORMAT_TIME;

  Glib::RefPtr<Gst::Query> query = Gst::QueryPosition::create(fmt);

  if(m_main_pipeline->query(query))
  {
    Glib::RefPtr<Gst::QueryPosition> posQuery =
      Glib::RefPtr<Gst::QueryPosition>::cast_dynamic(query);

    gint64 pos = posQuery->parse();

    const gint64 new_pos =
      ((pos + skip_amount) < m_duration) ? (pos + skip_amount) : m_duration;

    Glib::RefPtr<Gst::Event> event = Gst::EventSeek::create(1.0, fmt,
      Gst::SEEK_FLAG_FLUSH, Gst::SEEK_TYPE_SET, new_pos,
      Gst::SEEK_TYPE_NONE, -1);

    Glib::RefPtr<Gst::EventSeek> seekEvent =
      Glib::RefPtr<Gst::EventSeek>::cast_dynamic(event);

    if(m_main_pipeline->send_event(seekEvent))
    {
      m_progress_scale.set_value(double(new_pos) / m_duration);
      display_label_progress(new_pos, m_duration);
    }
    else
      std::cerr << "Could not seek." << std::endl;
  }
}

void PlayerWindow::on_button_open()
{
  static Glib::ustring working_dir = Glib::get_home_dir();
  
  //Offer a file chooser dialog to the user:
  Gtk::FileChooserDialog chooser(*this,
    "Select ogg file", Gtk::FILE_CHOOSER_ACTION_OPEN);
  chooser.add_button(Gtk::Stock::CANCEL, Gtk::RESPONSE_CANCEL);
  chooser.add_button(Gtk::Stock::OK, Gtk::RESPONSE_OK);

  Gtk::FileFilter filter;
  filter.add_mime_type("application/ogg");
  filter.set_name("Ogg files");
  chooser.set_filter(filter);
  
  chooser.set_current_folder(working_dir);
  
  const int response = chooser.run();
  if(response == Gtk::RESPONSE_OK)
  {
    working_dir = chooser.get_current_folder();

    // Set uri on the file source. 
    const std::string uri = chooser.get_uri();
    m_source_element->set_uri(uri);
    set_title(uri);

    m_play_button.set_sensitive();
    display_label_progress(0, 0);
  }
}

bool PlayerWindow::on_timeout()
{
  Gst::Format fmt = Gst::FORMAT_TIME;
  gint64 pos = 0;

  if(m_main_pipeline->query_position(fmt, pos)
    && m_main_pipeline->query_duration(fmt, m_duration))
  {
    m_progress_scale.set_value(double(pos) / m_duration);
    display_label_progress(pos, m_duration);
  }

  return true;
}

void PlayerWindow::display_label_progress(gint64 pos, gint64 len)
{
  std::ostringstream locationStream(std::ostringstream::out);
  locationStream << std::right << std::setfill('0') << 
    std::setw(3) << Gst::get_hours(pos) << ":" <<
    std::setw(2) << Gst::get_minutes(pos) << ":" <<
    std::setw(2) << Gst::get_seconds(pos) << "." <<
    std::setw(9) << std::left << Gst::get_fractional_seconds(pos);

  std::ostringstream durationStream(std::ostringstream::out);
  durationStream << std::right << std::setfill('0') <<
    std::setw(3) << Gst::get_hours(len) << ":" <<
    std::setw(2) << Gst::get_minutes(len) << ":" <<
    std::setw(2) << Gst::get_seconds(len) << "." <<
    std::setw(9) << std::left << Gst::get_fractional_seconds(len);

  m_progress_label.set_text(
    locationStream.str() + " / " + durationStream.str() );
}

PlayerWindow::~PlayerWindow()
{
  m_main_pipeline->get_bus()->remove_watch(m_watch_id);
}
