/*
    Copyright (C) 2000-2006 Paul Davis

    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 2 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, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

*/

#include <fstream>
#include <cassert>
#include <cstdio>
#include <unistd.h>
#include <cmath>
#include <cerrno>
#include <string>
#include <climits>
#include <fcntl.h>
#include <cstdlib>
#include <ctime>
#include <sys/stat.h>
#include <sys/mman.h>


#include "pbd/error.h"
#include "pbd/basename.h"
#include <glibmm/thread.h>
#include "pbd/xml++.h"
#include "pbd/memento_command.h"

#include "ardour/ardour.h"
#include "ardour/audioengine.h"
#include "ardour/debug.h"
#include "ardour/diskstream.h"
#include "ardour/utils.h"
#include "ardour/configuration.h"
#include "ardour/audiofilesource.h"
#include "ardour/send.h"
#include "ardour/playlist.h"
#include "ardour/cycle_timer.h"
#include "ardour/region.h"
#include "ardour/panner.h"
#include "ardour/session.h"
#include "ardour/io.h"
#include "ardour/track.h"

#include "i18n.h"
#include <locale.h>

using namespace std;
using namespace ARDOUR;
using namespace PBD;

/* XXX This goes uninitialized when there is no ~/.config/ardour3 directory.
 * I can't figure out why, so this will do for now (just stole the
 * default from configuration_vars.h).  0 is not a good value for
 * allocating buffer sizes..
 */
ARDOUR::framecnt_t Diskstream::disk_io_chunk_frames = 1024 * 256;

PBD::Signal0<void>                Diskstream::DiskOverrun;
PBD::Signal0<void>                Diskstream::DiskUnderrun;

Diskstream::Diskstream (Session &sess, const string &name, Flag flag)
	: SessionObject(sess, name)
        , i_am_the_modifier (0)
        , _track (0)
        , _record_enabled (0)
        , _visible_speed (1.0f)
        , _actual_speed (1.0f)
        , _buffer_reallocation_required (false)
        , _seek_required (false)
        , force_refill (false)
        , capture_start_frame (0)
        , capture_captured (0)
        , was_recording (false)
        , adjust_capture_position (0)
        , _capture_offset (0)
        , _roll_delay (0)
        , first_recordable_frame (max_framepos)
        , last_recordable_frame (max_framepos)
        , last_possibly_recording (0)
        , _alignment_style (ExistingMaterial)
        , _scrubbing (false)
        , _slaved (false)
        , loop_location (0)
        , overwrite_frame (0)
        , overwrite_offset (0)
        , _pending_overwrite (false)
        , overwrite_queued (false)
        , wrap_buffer_size (0)
        , speed_buffer_size (0)
        , _speed (1.0)
        , _target_speed (_speed)
        , file_frame (0)
        , playback_sample (0)
        , playback_distance (0)
        , _read_data_count (0)
        , _write_data_count (0)
        , in_set_state (false)
        , _persistent_alignment_style (ExistingMaterial)
        , first_input_change (true)
        , _flags (flag)

{
}

Diskstream::Diskstream (Session& sess, const XMLNode& /*node*/)
	: SessionObject(sess, "unnamed diskstream")
        , i_am_the_modifier (0)
        , _track (0)
        , _record_enabled (0)
        , _visible_speed (1.0f)
        , _actual_speed (1.0f)
        , _buffer_reallocation_required (false)
        , _seek_required (false)
        , force_refill (false)
        , capture_start_frame (0)
        , capture_captured (0)
        , was_recording (false)
        , adjust_capture_position (0)
        , _capture_offset (0)
        , _roll_delay (0)
        , first_recordable_frame (max_framepos)
        , last_recordable_frame (max_framepos)
        , last_possibly_recording (0)
        , _alignment_style (ExistingMaterial)
        , _scrubbing (false)
        , _slaved (false)
        , loop_location (0)
        , overwrite_frame (0)
        , overwrite_offset (0)
        , _pending_overwrite (false)
        , overwrite_queued (false)
        , wrap_buffer_size (0)
        , speed_buffer_size (0)
        , _speed (1.0)
        , _target_speed (_speed)
        , file_frame (0)
        , playback_sample (0)
        , playback_distance (0)
        , _read_data_count (0)
        , _write_data_count (0)
        , in_set_state (false)
        , _persistent_alignment_style (ExistingMaterial)
        , first_input_change (true)
        , _flags (Recordable)
{
}

Diskstream::~Diskstream ()
{
	DEBUG_TRACE (DEBUG::Destruction, string_compose ("Diskstream %1 deleted\n", _name));

	if (_playlist) {
		_playlist->release ();
	}
}

void
Diskstream::set_track (Track* t)
{
	_track = t;
	_io = _track->input();

	ic_connection.disconnect();
	_io->changed.connect_same_thread (ic_connection, boost::bind (&Diskstream::handle_input_change, this, _1, _2));

	input_change_pending = IOChange::ConfigurationChanged;
	non_realtime_input_change ();
	set_align_style_from_io ();

	_track->Destroyed.connect_same_thread (*this, boost::bind (&Diskstream::route_going_away, this));
}

void
Diskstream::handle_input_change (IOChange change, void * /*src*/)
{
	Glib::Mutex::Lock lm (state_lock);

        if (change.type & IOChange::ConfigurationChanged) {
                if (!(input_change_pending.type & change.type)) {
                        input_change_pending.type = IOChange::Type (input_change_pending.type | change.type);
                        _session.request_input_change_handling ();
                }
        }
}

void
Diskstream::non_realtime_set_speed ()
{
	if (_buffer_reallocation_required)
	{
		Glib::Mutex::Lock lm (state_lock);
		allocate_temporary_buffers ();

		_buffer_reallocation_required = false;
	}

	if (_seek_required) {
		if (speed() != 1.0f || speed() != -1.0f) {
			seek ((framepos_t) (_session.transport_frame() * (double) speed()), true);
		}
		else {
			seek (_session.transport_frame(), true);
		}

		_seek_required = false;
	}
}

bool
Diskstream::realtime_set_speed (double sp, bool global)
{
	bool changed = false;
	double new_speed = sp * _session.transport_speed();

	if (_visible_speed != sp) {
		_visible_speed = sp;
		changed = true;
	}

	if (new_speed != _actual_speed) {

		framecnt_t required_wrap_size = (framecnt_t) floor (_session.get_block_size() *
                                                                  fabs (new_speed)) + 1;

		if (required_wrap_size > wrap_buffer_size) {
			_buffer_reallocation_required = true;
		}

		_actual_speed = new_speed;
		_target_speed = fabs(_actual_speed);
	}

	if (changed) {
		if (!global) {
			_seek_required = true;
		}
		SpeedChanged (); /* EMIT SIGNAL */
	}

	return _buffer_reallocation_required || _seek_required;
}

void
Diskstream::set_capture_offset ()
{
	if (_io == 0) {
		/* can't capture, so forget it */
		return;
	}

	_capture_offset = _io->latency();
}

void
Diskstream::set_align_style (AlignStyle a)
{
	if (record_enabled() && _session.actively_recording()) {
		return;
	}

	if (a != _alignment_style) {
		_alignment_style = a;
		AlignmentStyleChanged ();
	}
}

int
Diskstream::set_loop (Location *location)
{
	if (location) {
		if (location->start() >= location->end()) {
			error << string_compose(_("Location \"%1\" not valid for track loop (start >= end)"), location->name()) << endl;
			return -1;
		}
	}

	loop_location = location;

	LoopSet (location); /* EMIT SIGNAL */
	return 0;
}

/** Get the start position (in session frames) of the nth capture in the current pass */
ARDOUR::framepos_t
Diskstream::get_capture_start_frame (uint32_t n) const
{
	Glib::Mutex::Lock lm (capture_info_lock);

	if (capture_info.size() > n) {
		/* this is a completed capture */
		return capture_info[n]->start;
	} else {
		/* this is the currently in-progress capture */
		return capture_start_frame;
	}
}

ARDOUR::framecnt_t
Diskstream::get_captured_frames (uint32_t n) const
{
	Glib::Mutex::Lock lm (capture_info_lock);

	if (capture_info.size() > n) {
		/* this is a completed capture */
		return capture_info[n]->frames;
	} else {  
		/* this is the currently in-progress capture */
		return capture_captured;
	}
}

void
Diskstream::set_roll_delay (ARDOUR::framecnt_t nframes)
{
	_roll_delay = nframes;
}

int
Diskstream::use_playlist (boost::shared_ptr<Playlist> playlist)
{
        if (!playlist) {
                return 0;
        }

        bool prior_playlist = false;

	{
		Glib::Mutex::Lock lm (state_lock);

		if (playlist == _playlist) {
			return 0;
		}

		playlist_connections.drop_connections ();

		if (_playlist) {
			_playlist->release();
                        prior_playlist = true;
		}

		_playlist = playlist;
		_playlist->use();

		if (!in_set_state && recordable()) {
			reset_write_sources (false);
		}

		_playlist->ContentsChanged.connect_same_thread (playlist_connections, boost::bind (&Diskstream::playlist_modified, this));
		_playlist->DropReferences.connect_same_thread (playlist_connections, boost::bind (&Diskstream::playlist_deleted, this, boost::weak_ptr<Playlist>(_playlist)));
		_playlist->RangesMoved.connect_same_thread (playlist_connections, boost::bind (&Diskstream::playlist_ranges_moved, this, _1, _2));
	}

	/* don't do this if we've already asked for it *or* if we are setting up
	   the diskstream for the very first time - the input changed handling will
	   take care of the buffer refill.
	*/

	if (!overwrite_queued && prior_playlist) {
		_session.request_overwrite_buffer (_track);
		overwrite_queued = true;
	}

	PlaylistChanged (); /* EMIT SIGNAL */
	_session.set_dirty ();

	return 0;
}

void
Diskstream::playlist_changed (const PropertyChange&)
{
	playlist_modified ();
}

void
Diskstream::playlist_modified ()
{
	if (!i_am_the_modifier && !overwrite_queued) {
		_session.request_overwrite_buffer (_track);
		overwrite_queued = true;
	}
}

void
Diskstream::playlist_deleted (boost::weak_ptr<Playlist> wpl)
{
	boost::shared_ptr<Playlist> pl (wpl.lock());

	if (pl == _playlist) {

		/* this catches an ordering issue with session destruction. playlists
		   are destroyed before diskstreams. we have to invalidate any handles
		   we have to the playlist.
		*/

		if (_playlist) {
			_playlist.reset ();
		}
	}
}

bool
Diskstream::set_name (const string& str)
{
	if (_name != str) {
		assert(playlist());
		playlist()->set_name (str);

		SessionObject::set_name(str);

		if (!in_set_state && recordable()) {
			/* rename existing capture files so that they have the correct name */
			return rename_write_sources ();
		} else {
			return false;
		}
	}

	return true;
}

void
Diskstream::playlist_ranges_moved (list< Evoral::RangeMove<framepos_t> > const & movements_frames, bool from_undo)
{
	/* If we're coming from an undo, it will have handled
	   automation undo (it must, since automation-follows-regions
	   can lose automation data).  Hence we can do nothing here.
	*/
	
	if (from_undo) {
		return;
	}
	
	if (!_track || Config->get_automation_follows_regions () == false) {
		return;
	}

	list< Evoral::RangeMove<double> > movements;

	for (list< Evoral::RangeMove<framepos_t> >::const_iterator i = movements_frames.begin();
	     i != movements_frames.end();
	     ++i) {

		movements.push_back(Evoral::RangeMove<double>(i->from, i->length, i->to));
	}

	/* move panner automation */
	boost::shared_ptr<Panner> p = _track->main_outs()->panner ();
	if (p) {
		for (uint32_t i = 0; i < p->npanners (); ++i) {
			boost::shared_ptr<AutomationList> pan_alist = p->streampanner(i).pan_control()->alist();
			XMLNode & before = pan_alist->get_state ();
			bool const things_moved = pan_alist->move_ranges (movements);
			if (things_moved) {
				_session.add_command (new MementoCommand<AutomationList> (
							      *pan_alist.get(), &before, &pan_alist->get_state ()));
			}
		}
	}

	/* move processor automation */
	_track->foreach_processor (boost::bind (&Diskstream::move_processor_automation, this, _1, movements_frames));
}

void
Diskstream::move_processor_automation (boost::weak_ptr<Processor> p, list< Evoral::RangeMove<framepos_t> > const & movements_frames)
{
	boost::shared_ptr<Processor> processor (p.lock ());
	if (!processor) {
		return;
	}

	list< Evoral::RangeMove<double> > movements;
	for (list< Evoral::RangeMove<framepos_t> >::const_iterator i = movements_frames.begin(); i != movements_frames.end(); ++i) {
		movements.push_back(Evoral::RangeMove<double>(i->from, i->length, i->to));
	}

	set<Evoral::Parameter> const a = processor->what_can_be_automated ();

	for (set<Evoral::Parameter>::iterator i = a.begin (); i != a.end (); ++i) {
		boost::shared_ptr<AutomationList> al = processor->automation_control(*i)->alist();
		XMLNode & before = al->get_state ();
		bool const things_moved = al->move_ranges (movements);
		if (things_moved) {
			_session.add_command (
				new MementoCommand<AutomationList> (
					*al.get(), &before, &al->get_state ()
					)
				);
		}
	}
}

void
Diskstream::check_record_status (framepos_t transport_frame, bool can_record)
{
	int possibly_recording;
	int rolling;
	int change;
	const int transport_rolling = 0x4;
	const int track_rec_enabled = 0x2;
	const int global_rec_enabled = 0x1;
        const int fully_rec_enabled = (transport_rolling|track_rec_enabled|global_rec_enabled);

	/* merge together the 3 factors that affect record status, and compute
	   what has changed.
	*/

	rolling = _session.transport_speed() != 0.0f;
	possibly_recording = (rolling << 2) | (record_enabled() << 1) | can_record;
	change = possibly_recording ^ last_possibly_recording;

	if (possibly_recording == last_possibly_recording) {
		return;
	}
        if (possibly_recording == fully_rec_enabled) {

                if (last_possibly_recording == fully_rec_enabled) {
                        return;
                }

                /* we transitioned to recording. lets see if its transport based or a punch */
                
		first_recordable_frame = transport_frame + _capture_offset;
		last_recordable_frame = max_framepos;
		capture_start_frame = transport_frame;

                if (change & transport_rolling) {

                        /* transport-change (started rolling) */
                        
			if (_alignment_style == ExistingMaterial) {
                                
                                /* there are two delays happening:
                                   
                                   1) inbound, represented by _capture_offset
                                   2) outbound, represented by _session.worst_output_latency()

                                   the first sample to record occurs when the larger of these
                                   two has elapsed, since they occur in parallel.

                                   since we've already added _capture_offset, just add the
                                   difference if _session.worst_output_latency() is larger.
                                */

                                if (_capture_offset < _session.worst_output_latency()) {
                                        first_recordable_frame += (_session.worst_output_latency() - _capture_offset);
                                } 
                        } else {
				first_recordable_frame += _roll_delay;
  			}
                        
                } else {

                        /* punch in */

			if (_alignment_style == ExistingMaterial) {

				/* There are two kinds of punch:
                                   
                                   manual punch in happens at the correct transport frame
                                   because the user hit a button. but to get alignment correct 
                                   we have to back up the position of the new region to the 
                                   appropriate spot given the roll delay.

                                   autopunch toggles recording at the precise
				   transport frame, and then the DS waits
				   to start recording for a time that depends
				   on the output latency.

                                   XXX: BUT THIS CODE DOESN'T DIFFERENTIATE !!!

				*/

                                if (_capture_offset < _session.worst_output_latency()) {
                                        /* see comment in ExistingMaterial block above */
                                        first_recordable_frame += (_session.worst_output_latency() - _capture_offset);
                                }

			} else {
				capture_start_frame -= _roll_delay;
			}
                }
                
                prepare_record_status (capture_start_frame);

        } else {

                if (last_possibly_recording == fully_rec_enabled) {

                        /* we were recording last time */
                        
                        if (change & transport_rolling) {
                                /* transport-change (stopped rolling): last_recordable_frame was set in ::prepare_to_stop() */
                                
                        } else {
                                /* punch out */
                                
                                last_recordable_frame = transport_frame + _capture_offset;
                                
                                if (_alignment_style == ExistingMaterial) {
                                        if (_session.worst_output_latency() > _capture_offset) {
                                                last_recordable_frame += (_session.worst_output_latency() - _capture_offset);
                                        }
                                } else {
                                        last_recordable_frame += _roll_delay;
                                }
                        }
                }
        }

	last_possibly_recording = possibly_recording;
}

void
Diskstream::route_going_away ()
{
	_io.reset ();
}

void
Diskstream::calculate_record_range(OverlapType ot, framepos_t transport_frame, framecnt_t nframes,
				   framecnt_t & rec_nframes, framecnt_t & rec_offset)
{
	switch (ot) {
	case OverlapNone:
		rec_nframes = 0;
		break;

	case OverlapInternal:
		/*     ----------    recrange
		         |---|       transrange
		*/
		rec_nframes = nframes;
		rec_offset = 0;
		break;

	case OverlapStart:
		/*    |--------|    recrange
	        -----|          transrange
		*/
		rec_nframes = transport_frame + nframes - first_recordable_frame;
		if (rec_nframes) {
			rec_offset = first_recordable_frame - transport_frame;
		}
		break;

	case OverlapEnd:
		/*    |--------|    recrange
		         |--------  transrange
		*/
		rec_nframes = last_recordable_frame - transport_frame;
		rec_offset = 0;
		break;

	case OverlapExternal:
		/*    |--------|    recrange
		    --------------  transrange
		*/
		rec_nframes = last_recordable_frame - first_recordable_frame;
		rec_offset = first_recordable_frame - transport_frame;
		break;
	}
}

void
Diskstream::prepare_to_stop (framepos_t pos)
{
        last_recordable_frame = pos + _capture_offset;
}