#include "quakedef.h"

#ifdef USE_FMOD
#include "fmod.h"
#include "fmod_errors.h"

extern qboolean sound_started;	// in snd_dma.c

FMOD_SYSTEM *fmod_system = NULL;
static qboolean fmod_ownership = false;
static int fmod_samplerate;
static float old_volume = -1.0f;

static FMOD_CHANNELGROUP *sfx_channelGroup = NULL;

static const char *FMOD_SpeakerModeString(FMOD_SPEAKERMODE speakermode);
static float SND_FMOD_Attenuation(FMOD_CHANNELCONTROL *channelControl, float distance);

// Copy and convert coordinate system
#define FMOD_VectorCopy(a, b)	{(b).x=(a)[0];(b).y=(a)[2];(b).z=(a)[1];}
#define	sound_nominal_clip_dist	1000.0

typedef struct entchannel_s
{
	int entnum;
	int entchannel;
	float dist_mult;
	FMOD_CHANNEL *channel;
} entchannel_t;

static entchannel_t entchannels[MAX_CHANNELS];

void S_Startup(void)
{
	FMOD_RESULT result;
	FMOD_SPEAKERMODE speakermode;
	unsigned int version;
	int driver, numchannels;
	char name[1024];

	// Create FMOD System if it doesn't exist already
	if (!fmod_system)
	{
		result = FMOD_System_Create(&fmod_system);
		if (result != FMOD_OK)
		{
			Con_Printf("Failed to create FMOD System: %s\n", FMOD_ErrorString(result));
			return;
		}

		fmod_ownership = true;
	}

	result = FMOD_System_GetVersion(fmod_system, &version);
	if (result != FMOD_OK)
	{
		Con_Printf("Failed to retrieve FMOD version: %s\n", FMOD_ErrorString(result));
		return;
	}

	result = FMOD_System_GetDriver(fmod_system, &driver);
	if (result != FMOD_OK)
	{
		Con_Printf("Failed to retrieve selected FMOD driver: %s\n", FMOD_ErrorString(result));
		return;
	}

	result = FMOD_System_GetDriverInfo(fmod_system, driver, name, sizeof(name), NULL, &fmod_samplerate, &speakermode, &numchannels);
	if (result != FMOD_OK)
	{
		Con_Printf("Failed to retrieve FMOD driver info: %s\n", FMOD_ErrorString(result));
		return;
	}

	Con_Printf("FMOD version %01x.%02x.%02x, driver '%s', %s speaker mode, %d Hz, %d channels\n",
		(version >> 16) & 0xff, (version >> 8) & 0xff, version & 0xff, name, FMOD_SpeakerModeString(speakermode), fmod_samplerate, numchannels);

	result = FMOD_System_CreateChannelGroup(fmod_system, "SFX", &sfx_channelGroup);
	if (result != FMOD_OK)
	{
		Con_Printf("Failed to create FMOD SFX channel group: %s\n", FMOD_ErrorString(result));
		return;
	}

	// Could use System::set3DRolloffCallback to set up a (attenuation / sound_nominal_clip_dist) distance multiplier (would need to use ChannelControl::setUserData to hold ref to attn value)
	// Note: sound_nominal_clip_dist could be dynamic to allow a small sound 'bubble' for local multiplayer
	FMOD_ChannelGroup_Set3DMinMaxDistance(sfx_channelGroup, 0.0f, sound_nominal_clip_dist);
	FMOD_System_Set3DRolloffCallback(fmod_system, &SND_FMOD_Attenuation);

	memset(entchannels, 0, sizeof(entchannels));

	sound_started = true;
}

void S_Shutdown(void)
{
	Con_DPrintf("[FMOD] Shutdown\n");

	// Destroy any SFX channels still in use

	// If we created the FMOD System (and consequently own it), destroy it here
	if (fmod_ownership)
	{
		FMOD_System_Close(fmod_system);
		fmod_system = NULL;
		fmod_ownership = false;
	}
}

static unsigned int SND_GetDelay(const sfx_t *sfx)
{
	unsigned int delay;

	delay = 0.1 * fmod_samplerate;
	if (delay > sfx->samples)
		delay = sfx->samples;
	if (delay > 0)
		delay = rand() % delay;

	return delay;
}

static float SND_FMOD_Attenuation(FMOD_CHANNELCONTROL *channelcontrol, float distance)
{
	FMOD_RESULT result;
	entchannel_t *userdata;
	float scale;

	result = FMOD_Channel_GetUserData((FMOD_CHANNEL*)channelcontrol, &userdata);
	if (result != FMOD_OK || !userdata)
	{
		// Unknown type of channel or maybe it's a channel group, either way just return full volume in this case
		return 1.0f;
	}

	// Anything coming from the view entity will always be full volume
	if (userdata->entnum == cl.viewentity)
	{
		return 1.0f;
	}

	scale = 1.0f - (distance * userdata->dist_mult);
	if (scale < 0.0f)
		scale = 0.0f;

	return scale;
}

//static entchannel_t *SND_PickChannel(int entnum, int entchannel)
//{
//	int	ch_idx;
//	entchannel_t *channel;
//	FMOD_BOOL isplaying;
//
//	// Check for replacement sound, or find the best one to replace
//	for (ch_idx = MAX_AMBIENTS; ch_idx < MAX_CHANNELS; ch_idx++)
//	{
//		channel = &entchannels[ch_idx];
//
//		if (entchannel != 0		// channel 0 never overrides
//			&& channel->entnum == entnum
//			&& (channel->entchannel == entchannel || entchannel == -1))
//		{	
//			// always override sound from same entity
//			break;
//		}
//
//		// don't let monster sounds override player sounds
//		if (channel->entnum == cl.viewentity && entnum != cl.viewentity && channel->sfx)
//			continue;
//
//		if (snd_channels[ch_idx].end - paintedtime < life_left)
//		{
//			life_left = snd_channels[ch_idx].end - paintedtime;
//			first_to_die = ch_idx;
//		}
//	}
//
//	if (!channel)
//		return NULL;
//
//	if (channel->sfx && channel->channel)
//	{
//		FMOD_Channel_IsPlaying(channel->channel, &isplaying);
//		if (isplaying)
//		{
//			FMOD_Channel_Stop(channel->channel);
//		}
//		channel->channel = NULL;
//		channel->sfx = NULL;
//	}
//
//	channel->entnum = entnum;
//	channel->entchannel = entchannel;
//	return channel;
//}

void S_StartSound(int entnum, int entchannel, sfx_t *sfx, vec3_t origin, float fvol, float attenuation)	// Note: volume and attenuation are properly normalized here
{
	FMOD_CHANNEL *channel;
	FMOD_VECTOR position;
	FMOD_RESULT result;

	if (!fmod_system || !sfx)
		return;

	// TODO: check nosound cvar
	//return;	// HACK play no entity sfx for now

	S_LoadSound(sfx);
	if (!sfx->sound)
		return;

	// Find channel group for entity number (or create) => note entnum can also be some random hash value
		// ChannelControl::setMode => set to 3D
		// Can use channel group per entity to store entity-specific userdata, with maybe 16 fixed channel slots
	
	// Pre-define channels for each entity (could be an array of ints, probably array of entchannel_t structs)
	// For entchannel 0, dynamically select a free channel (or just play without doing anything, let FMOD handle it)
	// If channel at index entchannel >0 is already playing: stop
	//		Set userdata pointer to entchannel_t so we can check if the FMOD channel still belongs to this entity & entchannel, before checking if it's already playing
	// Special case entchannel -1 => just play locally on listener, no 3D (also override any sound already playing on entity)

	// System::playSound with paused = true
	result = FMOD_System_PlaySound(fmod_system, sfx->sound, sfx_channelGroup, 1, &channel);
	if (result != FMOD_OK)
	{
		Con_Printf("Failed to play FMOD sound: %s\n", FMOD_ErrorString(result));
		return;
	}

	// ChannelControl::set3DAttributes
	FMOD_VectorCopy(origin, position);
	FMOD_Channel_Set3DAttributes(channel, &position, NULL);
	FMOD_Channel_SetMode(channel, FMOD_LOOP_OFF);	// TODO: some entity sounds do need to loop, e.g. moving elevators. How is this done?
	FMOD_Channel_SetVolume(channel, fvol);
	FMOD_Channel_Set3DLevel(channel, entchannel < 0 ? 0.0f : 1.0f);	// entchannel -1 is used for local sounds
	
	// TODO: attenuation (this is just a quick hack to test)
	entchannel_t *userdata = (entchannel_t*)malloc(sizeof(entchannel_t));	// TODO: we REALLY need to allocate this properly, this is now a memory leak!!
	userdata->entnum = entnum;
	userdata->entchannel = entchannel;
	userdata->channel = channel;
	userdata->dist_mult = attenuation / sound_nominal_clip_dist;
	FMOD_Channel_SetUserData(channel, userdata);

	// TODO: use ChannelControl Callback to detect when the sound ends, then clear it from the entchannel_t list

	// Use ChannelControl::setDelay and ChannelControl::getDSPClock to add a delay to move sounds out of phase if necessary

	// ChannelControl::setPaused = false
	FMOD_Channel_SetPaused(channel, 0);
	
	// Store channel handle at position entchannel
}

// TODO: we're still missing Automatic Ambient sounds for water, lava, slime etc (see S_UpdateAmbientSounds)
void S_StaticSound(sfx_t *sfx, vec3_t origin, float vol, float attenuation)	// Note: volume and attenuation are in 0-255 range here
{
	FMOD_CHANNEL *channel;
	FMOD_VECTOR position;
	FMOD_RESULT result;
	unsigned long long dspclock;

	if (!fmod_system || !sfx)
		return;

	S_LoadSound(sfx);
	if (!sfx->sound)
		return;

	result = FMOD_System_PlaySound(fmod_system, sfx->sound, sfx_channelGroup, 1, &channel);
	if (result != FMOD_OK)
	{
		Con_Printf("Failed to play static FMOD sound: %s\n", FMOD_ErrorString(result));
		return;
	}

	FMOD_VectorCopy(origin, position);
	FMOD_Channel_Set3DAttributes(channel, &position, NULL);
	FMOD_Channel_SetMode(channel, FMOD_LOOP_NORMAL);
	FMOD_Channel_SetVolume(channel, vol / 255);
	
	// Set up attenuation info for use by the rolloff callback
	entchannel_t *userdata = (entchannel_t*)malloc(sizeof(entchannel_t));	// This is rather convenient. Can we use Z_Malloc here perhaps?
	userdata->entnum = -1;
	userdata->channel = channel;
	userdata->dist_mult = (attenuation / 64) / sound_nominal_clip_dist;
	FMOD_Channel_SetUserData(channel, userdata);

	// Add a random delay so that similar sounds don't phase together
	// Note: this isn't really authentic to the original Quake sound system, but it does improve the sense of directionality
	FMOD_ChannelGroup_GetDSPClock(sfx_channelGroup, &dspclock, NULL);
	FMOD_Channel_SetDelay(channel, dspclock + SND_GetDelay(sfx), 0, 0);

	FMOD_Channel_SetPaused(channel, 0);

	// Note: we can forget about the channel we just created, because all SFX channels will be stopped and released on level change through S_StopAllSounds
}

void S_StopSound(int entnum, int entchannel)
{

}

void S_StopAllSounds(qboolean clear)
{
	FMOD_ChannelGroup_Stop(sfx_channelGroup);

	if (clear)
		S_ClearBuffer();
}

void S_ClearBuffer(void)
{
	// TODO Use this to remove per-entity channel group and clear all userdata?
}

void S_Update(vec3_t origin, vec3_t forward, vec3_t right, vec3_t up)
{
	if (!fmod_system)
		return;

	if (old_volume != sfxvolume.value)
	{
		if (sfxvolume.value < 0)
			Cvar_SetQuick(&sfxvolume, "0");
		else if (sfxvolume.value > 1)
			Cvar_SetQuick(&sfxvolume, "1");

		old_volume = sfxvolume.value;
	}

	FMOD_VECTOR fmod_pos, fmod_forward, fmod_up;
	FMOD_VectorCopy(origin, fmod_pos);
	FMOD_VectorCopy(forward, fmod_forward);
	FMOD_VectorCopy(up, fmod_up);

	// TODO: set listener number based on player ID (for split-screen)
	FMOD_System_Set3DListenerAttributes(fmod_system, 0, &fmod_pos, NULL, &fmod_forward, &fmod_up);

	FMOD_ChannelGroup_SetVolume(sfx_channelGroup, sfxvolume.value);

	FMOD_System_Update(fmod_system);
}

void S_ExtraUpdate(void)
{
	FMOD_System_Update(fmod_system);
}

static void S_SetMasterMute(FMOD_BOOL mute)
{
	FMOD_CHANNELGROUP *master;

	if (!fmod_system)
		return;

	FMOD_System_GetMasterChannelGroup(fmod_system, &master);
	FMOD_ChannelGroup_SetMute(master, mute);
}

void S_BlockSound(void)
{
	S_SetMasterMute(1);
}

void S_UnblockSound(void)
{
	S_SetMasterMute(0);
}

sfxcache_t *S_LoadSound(sfx_t *s)
{
	char namebuffer[256];
	byte *data;
	int len, h;
	FMOD_CREATESOUNDEXINFO exinfo;
	FMOD_RESULT result;
#if _DEBUG
	FMOD_SOUND_TYPE type;
	FMOD_SOUND_FORMAT format;
	int channels, bits, loopcount;
#endif

	if (!fmod_system)
		return NULL;

	// Check if it's already loaded
	if (s->sound)
		return NULL;

	q_strlcpy(namebuffer, "sound/", sizeof(namebuffer));
	q_strlcat(namebuffer, s->name, sizeof(namebuffer));

	// We need to briefly open the file to figure out its length, which FMOD needs to know
	len = COM_OpenFile(namebuffer, &h, NULL);
	if (h >= 0)
		COM_CloseFile(h);

	data = COM_LoadHunkFile(namebuffer, NULL);
	if (!data)
	{
		Con_Printf("Couldn't load %s\n", namebuffer);
		return NULL;
	}

	memset(&exinfo, 0, sizeof(FMOD_CREATESOUNDEXINFO));
	exinfo.cbsize = sizeof(FMOD_CREATESOUNDEXINFO);
	exinfo.length = len;

	// System::createSound with FMOD_3D (sfx_t will need a pointer to FMOD_Sound)
	// Might need to set rate and width? FMOD can probably figure this out by itself based on the WAV file contents	
	result = FMOD_System_CreateSound(fmod_system, (const char*)data, FMOD_3D | FMOD_OPENMEMORY, &exinfo, &s->sound);
	if (result != FMOD_OK)
	{
		Con_Printf("Failed to create FMOD sound: %s\n", FMOD_ErrorString(result));
		return NULL;
	}

	FMOD_Sound_GetLength(s->sound, &s->samples, FMOD_TIMEUNIT_PCM);

#if _DEBUG
	FMOD_Sound_GetFormat(s->sound, &type, &format, &channels, &bits);
	FMOD_Sound_GetLoopCount(s->sound, &loopcount);
	Con_DPrintf("[FMOD] Loaded sound '%s': type %d, format %d, %d channel(s), %d bits, %d samples, loopcount = %d\n", s->name, type, format, channels, bits, s->samples, loopcount);
#endif

	return NULL;	// Return value is unused; FMOD has its own internal cache, we never need to use Quake's sfxcache_t
}

void S_TouchSound(const char *sample)
{

}

static const char *FMOD_SpeakerModeString(FMOD_SPEAKERMODE speakermode)
{
	switch (speakermode)
	{
	case FMOD_SPEAKERMODE_MONO:
		return "Mono";
	case FMOD_SPEAKERMODE_STEREO:
		return "Stereo";
	case FMOD_SPEAKERMODE_QUAD:
		return "4.0 Quad";
	case FMOD_SPEAKERMODE_SURROUND:
		return "5.0 Surround";
	case FMOD_SPEAKERMODE_5POINT1:
		return "5.1 Surround";
	case FMOD_SPEAKERMODE_7POINT1:
		return "7.1 Surround";
	case FMOD_SPEAKERMODE_7POINT1POINT4:
		return "7.1.4 Surround";
	default:
		return "Unknown";
	}
}

#endif	// USE_FMOD