/*
 * This file is part of OpenTTD.
 * OpenTTD 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, version 2.
 * OpenTTD 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 OpenTTD. If not, see <http://www.gnu.org/licenses/>.
 */

/** @file sound.cpp Handling of playing sounds. */

#include "stdafx.h"
#include "landscape.h"
#include "mixer.h"
#include "newgrf_sound.h"
#include "random_access_file_type.h"
#include "window_gui.h"
#include "vehicle_base.h"

/* The type of set we're replacing */
#define SET_TYPE "sounds"
#include "base_media_func.h"

#include "safeguards.h"

static SoundEntry _original_sounds[ORIGINAL_SAMPLE_COUNT];

static void OpenBankFile(const std::string &filename)
{
	/**
	 * The sound file for the original sounds, i.e. those not defined/overridden by a NewGRF.
	 * Needs to be kept alive during the game as _original_sounds[n].file refers to this.
	 */
	static std::unique_ptr<RandomAccessFile> original_sound_file;

	memset(_original_sounds, 0, sizeof(_original_sounds));

	/* If there is no sound file (nosound set), don't load anything */
	if (filename.empty()) return;

	original_sound_file.reset(new RandomAccessFile(filename, BASESET_DIR));
	size_t pos = original_sound_file->GetPos();
	uint count = original_sound_file->ReadDword();

	/* The new format has the highest bit always set */
	bool new_format = HasBit(count, 31);
	ClrBit(count, 31);
	count /= 8;

	/* Simple check for the correct number of original sounds. */
	if (count != ORIGINAL_SAMPLE_COUNT) {
		/* Corrupt sample data? Just leave the allocated memory as those tell
		 * there is no sound to play (size = 0 due to calloc). Not allocating
		 * the memory disables valid NewGRFs that replace sounds. */
		Debug(misc, 6, "Incorrect number of sounds in '{}', ignoring.", filename);
		return;
	}

	original_sound_file->SeekTo(pos, SEEK_SET);

	for (uint i = 0; i != ORIGINAL_SAMPLE_COUNT; i++) {
		_original_sounds[i].file = original_sound_file.get();
		_original_sounds[i].file_offset = GB(original_sound_file->ReadDword(), 0, 31) + pos;
		_original_sounds[i].file_size = original_sound_file->ReadDword();
	}

	for (uint i = 0; i != ORIGINAL_SAMPLE_COUNT; i++) {
		SoundEntry *sound = &_original_sounds[i];
		char name[255];

		original_sound_file->SeekTo(sound->file_offset, SEEK_SET);

		/* Check for special case, see else case */
		original_sound_file->ReadBlock(name, original_sound_file->ReadByte()); // Read the name of the sound
		if (new_format || strcmp(name, "Corrupt sound") != 0) {
			original_sound_file->SeekTo(12, SEEK_CUR); // Skip past RIFF header

			/* Read riff tags */
			for (;;) {
				uint32_t tag = original_sound_file->ReadDword();
				uint32_t size = original_sound_file->ReadDword();

				if (tag == ' tmf') {
					original_sound_file->ReadWord();                          // wFormatTag
					sound->channels = original_sound_file->ReadWord();        // wChannels
					sound->rate     = original_sound_file->ReadDword();       // samples per second
					if (!new_format) sound->rate = 11025;                      // seems like all old samples should be played at this rate.
					original_sound_file->ReadDword();                         // avg bytes per second
					original_sound_file->ReadWord();                          // alignment
					sound->bits_per_sample = original_sound_file->ReadByte(); // bits per sample
					original_sound_file->SeekTo(size - (2 + 2 + 4 + 4 + 2 + 1), SEEK_CUR);
				} else if (tag == 'atad') {
					sound->file_size = size;
					sound->file = original_sound_file.get();
					sound->file_offset = original_sound_file->GetPos();
					break;
				} else {
					sound->file_size = 0;
					break;
				}
			}
		} else {
			/*
			 * Special case for the jackhammer sound
			 * (name in sample.cat is "Corrupt sound")
			 * It's no RIFF file, but raw PCM data
			 */
			sound->channels = 1;
			sound->rate = 11025;
			sound->bits_per_sample = 8;
			sound->file = original_sound_file.get();
			sound->file_offset = original_sound_file->GetPos();
		}
	}
}

static bool SetBankSource(MixerChannel *mc, const SoundEntry *sound)
{
	assert(sound != nullptr);

	/* Check for valid sound size. */
	if (sound->file_size == 0 || sound->file_size > ((size_t)-1) - 2) return false;

	int8_t *mem = MallocT<int8_t>(sound->file_size + 2);
	/* Add two extra bytes so rate conversion can read these
	 * without reading out of its input buffer. */
	mem[sound->file_size    ] = 0;
	mem[sound->file_size + 1] = 0;

	RandomAccessFile *file = sound->file;
	file->SeekTo(sound->file_offset, SEEK_SET);
	file->ReadBlock(mem, sound->file_size);

	/* 16-bit PCM WAV files should be signed by default */
	if (sound->bits_per_sample == 8) {
		for (uint i = 0; i != sound->file_size; i++) {
			mem[i] += -128; // Convert unsigned sound data to signed
		}
	}

#if TTD_ENDIAN == TTD_BIG_ENDIAN
	if (sound->bits_per_sample == 16) {
		uint num_samples = sound->file_size / 2;
		int16_t *samples = (int16_t *)mem;
		for (uint i = 0; i < num_samples; i++) {
			samples[i] = BSWAP16(samples[i]);
		}
	}
#endif

	assert(sound->bits_per_sample == 8 || sound->bits_per_sample == 16);
	assert(sound->channels == 1);
	assert(sound->file_size != 0 && sound->rate != 0);

	MxSetChannelRawSrc(mc, mem, sound->file_size, sound->rate, sound->bits_per_sample == 16);

	return true;
}

void InitializeSound()
{
	Debug(misc, 1, "Loading sound effects...");
	OpenBankFile(BaseSounds::GetUsedSet()->files->filename);
}

/* Low level sound player */
static void StartSound(SoundID sound_id, float pan, uint volume)
{
	if (volume == 0) return;

	SoundEntry *sound = GetSound(sound_id);
	if (sound == nullptr) return;

	/* NewGRF sound that wasn't loaded yet? */
	if (sound->rate == 0 && sound->file != nullptr) {
		if (!LoadNewGRFSound(sound)) {
			/* Mark as invalid. */
			sound->file = nullptr;
			return;
		}
	}

	/* Empty sound? */
	if (sound->rate == 0) return;

	MixerChannel *mc = MxAllocateChannel();
	if (mc == nullptr) return;

	if (!SetBankSource(mc, sound)) return;

	/* Apply the sound effect's own volume. */
	volume = sound->volume * volume;

	MxSetChannelVolume(mc, volume, pan);
	MxActivateChannel(mc);
}


static const byte _vol_factor_by_zoom[] = {255, 255, 255, 190, 134, 87};
static_assert(lengthof(_vol_factor_by_zoom) == ZOOM_LVL_COUNT);

static const byte _sound_base_vol[] = {
	128,  90, 128, 128, 128, 128, 128, 128,
	128,  90,  90, 128, 128, 128, 128, 128,
	128, 128, 128,  80, 128, 128, 128, 128,
	128, 128, 128, 128, 128, 128, 128, 128,
	128, 128,  90,  90,  90, 128,  90, 128,
	128,  90, 128, 128, 128,  90, 128, 128,
	128, 128, 128, 128,  90, 128, 128, 128,
	128,  90, 128, 128, 128, 128, 128, 128,
	128, 128,  90,  90,  90, 128, 128, 128,
	 90,
};

static const byte _sound_idx[] = {
	 2,  3,  4,  5,  6,  7,  8,  9,
	10, 11, 12, 13, 14, 15, 16, 17,
	18, 19, 20, 21, 22, 23, 24, 25,
	26, 27, 28, 29, 30, 31, 32, 33,
	34, 35, 36, 37, 38, 39, 40,  0,
	 1, 41, 42, 43, 44, 45, 46, 47,
	48, 49, 50, 51, 52, 53, 54, 55,
	56, 57, 58, 59, 60, 61, 62, 63,
	64, 65, 66, 67, 68, 69, 70, 71,
	72,
};

void SndCopyToPool()
{
	SoundEntry *sound = AllocateSound(ORIGINAL_SAMPLE_COUNT);
	for (uint i = 0; i < ORIGINAL_SAMPLE_COUNT; i++) {
		sound[i] = _original_sounds[_sound_idx[i]];
		sound[i].volume = _sound_base_vol[i];
		sound[i].priority = 0;
	}
}

/**
 * Decide 'where' (between left and right speaker) to play the sound effect.
 * Note: Callers must determine if sound effects are enabled. This plays a sound regardless of the setting.
 * @param sound Sound effect to play
 * @param left   Left edge of virtual coordinates where the sound is produced
 * @param right  Right edge of virtual coordinates where the sound is produced
 * @param top    Top edge of virtual coordinates where the sound is produced
 * @param bottom Bottom edge of virtual coordinates where the sound is produced
 */
static void SndPlayScreenCoordFx(SoundID sound, int left, int right, int top, int bottom)
{
	/* Iterate from back, so that main viewport is checked first */
	for (const Window *w : Window::IterateFromBack()) {
		const Viewport *vp = w->viewport;

		if (vp != nullptr &&
				left < vp->virtual_left + vp->virtual_width && right > vp->virtual_left &&
				top < vp->virtual_top + vp->virtual_height && bottom > vp->virtual_top) {
			int screen_x = (left + right) / 2 - vp->virtual_left;
			int width = (vp->virtual_width == 0 ? 1 : vp->virtual_width);
			float panning = (float)screen_x / width;

			StartSound(
				sound,
				panning,
				_vol_factor_by_zoom[vp->zoom - ZOOM_LVL_BEGIN]
			);
			return;
		}
	}
}

void SndPlayTileFx(SoundID sound, TileIndex tile)
{
	/* emits sound from center of the tile */
	int x = std::min(Map::MaxX() - 1, TileX(tile)) * TILE_SIZE + TILE_SIZE / 2;
	int y = std::min(Map::MaxY() - 1, TileY(tile)) * TILE_SIZE - TILE_SIZE / 2;
	int z = (y < 0 ? 0 : GetSlopePixelZ(x, y));
	Point pt = RemapCoords(x, y, z);
	y += 2 * TILE_SIZE;
	Point pt2 = RemapCoords(x, y, GetSlopePixelZ(x, y));
	SndPlayScreenCoordFx(sound, pt.x, pt2.x, pt.y, pt2.y);
}

void SndPlayVehicleFx(SoundID sound, const Vehicle *v)
{
	SndPlayScreenCoordFx(sound,
		v->coord.left, v->coord.right,
		v->coord.top, v->coord.bottom
	);
}

void SndPlayFx(SoundID sound)
{
	StartSound(sound, 0.5, UINT8_MAX);
}

INSTANTIATE_BASE_MEDIA_METHODS(BaseMedia<SoundsSet>, SoundsSet)

/** Names corresponding to the sound set's files */
static const char * const _sound_file_names[] = { "samples" };


template <class T, size_t Tnum_files, bool Tsearch_in_tars>
/* static */ const char * const *BaseSet<T, Tnum_files, Tsearch_in_tars>::file_names = _sound_file_names;

template <class Tbase_set>
/* static */ const char *BaseMedia<Tbase_set>::GetExtension()
{
	return ".obs"; // OpenTTD Base Sounds
}

template <class Tbase_set>
/* static */ bool BaseMedia<Tbase_set>::DetermineBestSet()
{
	if (BaseMedia<Tbase_set>::used_set != nullptr) return true;

	const Tbase_set *best = nullptr;
	for (const Tbase_set *c = BaseMedia<Tbase_set>::available_sets; c != nullptr; c = c->next) {
		/* Skip unusable sets */
		if (c->GetNumMissing() != 0) continue;

		if (best == nullptr ||
				(best->fallback && !c->fallback) ||
				best->valid_files < c->valid_files ||
				(best->valid_files == c->valid_files &&
					(best->shortname == c->shortname && best->version < c->version))) {
			best = c;
		}
	}

	BaseMedia<Tbase_set>::used_set = best;
	return BaseMedia<Tbase_set>::used_set != nullptr;
}