/*
    Copyright (C) 2012 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 "ardour/playlist.h"
#include "ardour/region.h"
#include "ardour/audioplaylist.h"
#include "ardour/audioregion.h"
#include "ardour/session.h"
#include "playlist_read_test.h"

CPPUNIT_TEST_SUITE_REGISTRATION (PlaylistReadTest);

using namespace std;
using namespace ARDOUR;

void
PlaylistReadTest::setUp ()
{
	AudioRegionTest::setUp ();

	_N = 1024;
	_buf = new Sample[_N];
	_mbuf = new Sample[_N];
	_gbuf = new float[_N];

	//_session->config.set_auto_xfade (false);

	for (int i = 0; i < _N; ++i) {
		_buf[i] = 0;
	}
}

void
PlaylistReadTest::tearDown ()
{
	delete[] _buf;
	delete[] _mbuf;
	delete[] _gbuf;

	AudioRegionTest::tearDown ();
}

void
PlaylistReadTest::singleReadTest ()
{
	/* Single-region read with fades */

	_audio_playlist->add_region (_ar[0], 0);
	_ar[0]->set_default_fade_in ();
	_ar[0]->set_default_fade_out ();
	CPPUNIT_ASSERT_EQUAL (double (64), _ar[0]->_fade_in->back()->when);
	CPPUNIT_ASSERT_EQUAL (double (64), _ar[0]->_fade_out->back()->when);
	_ar[0]->set_length (1024);
	_audio_playlist->read (_buf, _mbuf, _gbuf, 0, 256, 0);

	for (int i = 0; i < 64; ++i) {
		/* Note: this specific float casting is necessary so that the rounding
		   is done here the same as it is done in AudioPlaylist.
		*/
		CPPUNIT_ASSERT_DOUBLES_EQUAL (float (i * float (i / 63.0)), _buf[i], 1e-16);
	}

	for (int i = 64; i < 256; ++i) {
		CPPUNIT_ASSERT_EQUAL (i, int (_buf[i]));
	}
}

void
PlaylistReadTest::overlappingReadTest ()
{
	/* Overlapping read; _ar[0] and _ar[1] are both 1024 samples long, _ar[0] starts at 0,
	   _ar[1] starts at 128.  We test a read from 0 to 256, which should consist
	   of the start of _ar[0], with its fade in, followed by _ar[1]'s fade in (mixed with _ar[0]
	   faded out with the inverse gain), and some more of _ar[1].
	*/

	_audio_playlist->add_region (_ar[0], 0);
	_ar[0]->set_default_fade_in ();
	_ar[0]->set_default_fade_out ();
	CPPUNIT_ASSERT_EQUAL (double (64), _ar[0]->_fade_in->back()->when);
	CPPUNIT_ASSERT_EQUAL (double (64), _ar[0]->_fade_out->back()->when);
	_ar[0]->set_length (1024);

#if 0
	/* Note: these are ordinary fades, not xfades */
	CPPUNIT_ASSERT_EQUAL (false, _ar[0]->fade_in_is_xfade());
	CPPUNIT_ASSERT_EQUAL (false, _ar[0]->fade_out_is_xfade());
#endif

	_audio_playlist->add_region (_ar[1], 128);
	_ar[1]->set_default_fade_in ();
	_ar[1]->set_default_fade_out ();

#if 0
	/* Note: these are ordinary fades, not xfades */
	CPPUNIT_ASSERT_EQUAL (false, _ar[1]->fade_in_is_xfade());
	CPPUNIT_ASSERT_EQUAL (false, _ar[1]->fade_out_is_xfade());
#endif

	CPPUNIT_ASSERT_EQUAL (double (64), _ar[1]->_fade_in->back()->when);
	CPPUNIT_ASSERT_EQUAL (double (64), _ar[1]->_fade_out->back()->when);

	_ar[1]->set_length (1024);
	_audio_playlist->read (_buf, _mbuf, _gbuf, 0, 256, 0);

	/* _ar[0]'s fade in */
	for (int i = 0; i < 64; ++i) {
		/* Note: this specific float casting is necessary so that the rounding
		   is done here the same as it is done in AudioPlaylist; the gain factor
		   must be computed using double precision, with the result then cast
		   to float.
		*/
		CPPUNIT_ASSERT_DOUBLES_EQUAL (float (i * float (i / (double) 63)), _buf[i], 1e-16);
	}

	/* bit of _ar[0] */
	for (int i = 64; i < 128; ++i) {
		CPPUNIT_ASSERT_EQUAL (i, int (_buf[i]));
	}

	/* _ar[1]'s fade in with faded-out _ar[0] */
	for (int i = 0; i < 64; ++i) {
		/* Similar carry-on to above with float rounding */
		float const from_ar0 = (128 + i) * float (1 - (i / (double) 63));
		float const from_ar1 = i * float (i / (double) 63);
		CPPUNIT_ASSERT_DOUBLES_EQUAL (from_ar0 + from_ar1, _buf[i + 128], 1e-16);
	}
}

void
PlaylistReadTest::transparentReadTest ()
{
	_audio_playlist->add_region (_ar[0], 0);
	_ar[0]->set_default_fade_in ();
	_ar[0]->set_default_fade_out ();
	CPPUNIT_ASSERT_EQUAL (double (64), _ar[0]->_fade_in->back()->when);
	CPPUNIT_ASSERT_EQUAL (double (64), _ar[0]->_fade_out->back()->when);
	_ar[0]->set_length (1024);

	_audio_playlist->add_region (_ar[1], 0);
	_ar[1]->set_default_fade_in ();
	_ar[1]->set_default_fade_out ();
	CPPUNIT_ASSERT_EQUAL (double (64), _ar[1]->_fade_in->back()->when);
	CPPUNIT_ASSERT_EQUAL (double (64), _ar[1]->_fade_out->back()->when);
	_ar[1]->set_length (1024);
	_ar[1]->set_opaque (false);

	_audio_playlist->read (_buf, _mbuf, _gbuf, 0, 1024, 0);

	/* _ar[0] and _ar[1] fade-ins; _ar[1] is on top, but it is transparent, so
	   its fade in will not affect _ar[0]; _ar[0] will just fade in by itself,
	   and the two will be mixed.
	*/
	for (int i = 0; i < 64; ++i) {
		float const fade = i / (double) 63;
		float const ar0 = i * fade;
		float const ar1 = i * fade;
		CPPUNIT_ASSERT_DOUBLES_EQUAL (ar0 + ar1, _buf[i], 1e-16);
	}

	/* _ar[0] and _ar[1] bodies, mixed */
	for (int i = 64; i < (1024 - 64); ++i) {
		CPPUNIT_ASSERT_DOUBLES_EQUAL (float (i * 2), _buf[i], 1e-16);
	}

	/* _ar[0] and _ar[1] fade-outs, mixed */
	for (int i = (1024 - 64); i < 1024; ++i) {
		/* Ardour fades out from 1 to VERY_SMALL_SIGNAL, which is 0.0000001,
		   so this fade out expression is a little long-winded.
		*/
		float const fade = (((double) 1 - 0.0000001) / 63) * (1023 - i) + 0.0000001;
		float const ar0 = i * fade;
		float const ar1 = i * fade;
		CPPUNIT_ASSERT_DOUBLES_EQUAL (ar0 + ar1, _buf[i], 1e-16);
	}
}

/* A few tests just to check that nothing nasty is happening with
   memory corruption, really (for running with valgrind).
*/
void
PlaylistReadTest::miscReadTest ()
{
	_audio_playlist->add_region (_ar[0], 0);
	_ar[0]->set_default_fade_in ();
	_ar[0]->set_default_fade_out ();
	CPPUNIT_ASSERT_EQUAL (double (64), _ar[0]->_fade_in->back()->when);
	CPPUNIT_ASSERT_EQUAL (double (64), _ar[0]->_fade_out->back()->when);
	_ar[0]->set_length (128);

	/* Read for just longer than the region */
	_audio_playlist->read (_buf, _mbuf, _gbuf, 0, 129, 0);

	/* Read for much longer than the region */
	_audio_playlist->read (_buf, _mbuf, _gbuf, 0, 1024, 0);

	/* Read one sample */
	_audio_playlist->read (_buf, _mbuf, _gbuf, 53, 54, 0);
}

void
PlaylistReadTest::check_staircase (Sample* b, int offset, int N)
{
	for (int i = 0; i < N; ++i) {
		int const j = i + offset;
		CPPUNIT_ASSERT_EQUAL (j, int (b[i]));
	}
}

/* Check the case where we have
 *    |----------- Region A (transparent) ------------------|
 *                     |---- Region B (opaque) --|
 *
 * The result should be a mix of the two during region B's time.
 */

void
PlaylistReadTest::enclosedTransparentReadTest ()
{
	_audio_playlist->add_region (_ar[0], 256);
	/* These calls will result in a 64-sample fade */
	_ar[0]->set_fade_in_length (0);
	_ar[0]->set_fade_out_length (0);
	_ar[0]->set_length (256);

	_audio_playlist->add_region (_ar[1], 0);
	/* These calls will result in a 64-sample fade */
	_ar[1]->set_fade_in_length (0);
	_ar[1]->set_fade_out_length (0);
	_ar[1]->set_length (1024);
	_ar[1]->set_opaque (false);

	_audio_playlist->read (_buf, _mbuf, _gbuf, 0, 1024, 0);

	/* First 64 samples should just be _ar[1], faded in */
	for (int i = 0; i < 64; ++i) {
		CPPUNIT_ASSERT_DOUBLES_EQUAL (float (i * float (i / 63.0)), _buf[i], 1e-16);
	}

	/* Then some of _ar[1] with no fade */
	for (int i = 64; i < 256; ++i) {
		CPPUNIT_ASSERT_DOUBLES_EQUAL (i, _buf[i], 1e-16);
	}

	/* Then _ar[1] + _ar[0] (faded in) for 64 samples */
	for (int i = 256; i < (256 + 64); ++i) {
		CPPUNIT_ASSERT_DOUBLES_EQUAL (i + float ((i - 256) * float ((i - 256) / 63.0)), _buf[i], 1e-16);
	}

	/* Then _ar[1] + _ar[0] for 128 samples */
	for (int i = (256 + 64); i < (256 + 64 + 128); ++i) {
		CPPUNIT_ASSERT_DOUBLES_EQUAL (i + i - (256 + 64) + 64, _buf[i], 1e-16);
	}

	/* Then _ar[1] + _ar[0] (faded out) for 64 samples */
	for (int i = (256 + 64 + 128); i < 512; ++i) {
		float const ar0_without_fade = i - 256;
		/* See above regarding VERY_SMALL_SIGNAL SNAFU */
		float const fade = (((double) 1 - 0.0000001) / 63) * (511 - i) + 0.0000001;
		CPPUNIT_ASSERT_DOUBLES_EQUAL (i + float (ar0_without_fade * fade), _buf[i], 1e-16);
	}

	/* Then just _ar[1] for a while */
	for (int i = 512; i < (1024 - 64); ++i) {
		CPPUNIT_ASSERT_DOUBLES_EQUAL (i, _buf[i], 1e-16);
	}

	/* And finally _ar[1]'s fade out */
	for (int i = (1024 - 64); i < 1024; ++i) {
		/* See above regarding VERY_SMALL_SIGNAL SNAFU */
		float const fade = (((double) 1 - 0.0000001) / 63) * (1023 - i) + 0.0000001;
		CPPUNIT_ASSERT_DOUBLES_EQUAL (i * fade, _buf[i], 1e-16);

	}
}