#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 soundslot_s
{
	qboolean zone;
	FMOD_CHANNEL *channel;
	float dist_mult;
} soundslot_t;

typedef struct entsounds_s
{
	soundslot_t slots[8];
} entsounds_t;

static entsounds_t entsounds[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;
		}

		result = FMOD_System_SetSoftwareChannels(fmod_system, MAX_DYNAMIC_CHANNELS);
		if (result != FMOD_OK)
		{
			Con_Printf("Failed to set number of FMOD software channels: %s\n", FMOD_ErrorString(result));
			return;
		}

		result = FMOD_System_Init(fmod_system, MAX_CHANNELS, FMOD_INIT_NORMAL, NULL);
		if (result != FMOD_OK)
		{
			Con_Printf("Failed to initialize 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(entsounds, 0, sizeof(entsounds));

	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, float maxseconds)
{
	unsigned int delay;

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

	return delay;
}

/*
====================
SND_FMOD_Attenuation

Custom rolloff callback that mimics Quake's attenuation algorithm, 
whereby sounds can have varying degrees of distance rolloff.
====================
*/
static float SND_FMOD_Attenuation(FMOD_CHANNELCONTROL *channelcontrol, float distance)
{
	FMOD_RESULT result;
	soundslot_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;
	}

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

	return scale;
}

/*
=================
SND_FMOD_Callback

Channel control callback that ensures a channel's associated userdata
is properly cleared when the channel stops playing.
=================
*/
static FMOD_RESULT SND_FMOD_Callback(FMOD_CHANNELCONTROL *channelcontrol, FMOD_CHANNELCONTROL_TYPE controltype, FMOD_CHANNELCONTROL_CALLBACK_TYPE callbacktype, void *commanddata1, void *commanddata2)
{
	FMOD_RESULT result;
	soundslot_t *userdata;

	// We're only interested in notifications for when a channel is done playing a sound
	if (controltype != FMOD_CHANNELCONTROL_CHANNEL || callbacktype != FMOD_CHANNELCONTROL_CALLBACK_END)
		return FMOD_OK;

	result = FMOD_Channel_GetUserData((FMOD_CHANNEL*)channelcontrol, &userdata);
	if (result != FMOD_OK || !userdata)
	{
		return FMOD_OK;
	}

	// Clear the channel to signify that it's free
	userdata->channel = NULL;

	if (userdata->zone)
	{
		Z_Free(userdata);
	}

	return FMOD_OK;
}

static soundslot_t *SND_PickSoundSlot(int entnum, int entchannel)
{
	soundslot_t *slot;

	if (entnum < 0 || entnum >= MAX_CHANNELS || entchannel == 0 || entchannel > 7)
	{
		// Just play on any free channel
		slot = (soundslot_t*)Z_Malloc(sizeof(soundslot_t));
		slot->zone = true;
		return slot;
	}

	// Local sound, use the first slot and override anything already playing
	if (entchannel < 0)
		entchannel = 0;

	slot = &entsounds[entnum].slots[entchannel];
	if (slot->channel)
	{
		// Stop any sound already playing on this slot
		FMOD_Channel_Stop(slot->channel);
	}

	slot->zone = false;
	return slot;
}

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;
	soundslot_t *userdata;

	if (!fmod_system || !sfx)
		return;

	// TODO: check nosound cvar

	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 8-16 fixed channel slots
		// Note: entnum <0 is used by temporary entities, means there's no tie to any entity info at all: just play on any free channel

	userdata = SND_PickSoundSlot(entnum, entchannel);

	// 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;
	}

	// Set up callback data for rolloff and cleanup
	userdata->channel = channel;
	userdata->dist_mult = attenuation / sound_nominal_clip_dist;
	FMOD_Channel_SetUserData(channel, userdata);
	FMOD_Channel_SetCallback(channel, &SND_FMOD_Callback);

	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);
	
	// Anything coming from the view entity will always be full volume, and entchannel -1 is used for local sounds (e.g. menu sounds)
	FMOD_Channel_Set3DLevel(channel, entchannel < 0 || entnum == cl.viewentity ? 0.0f : 1.0f);
	
	// Use ChannelControl::setDelay and ChannelControl::getDSPClock to add a delay to move sounds out of phase if necessary

	FMOD_Channel_SetPaused(channel, 0);
}

// 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;
	soundslot_t *userdata;
	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
	userdata = SND_PickSoundSlot(-1, -1);
	userdata->channel = channel;
	userdata->dist_mult = (attenuation / 64) / sound_nominal_clip_dist;
	FMOD_Channel_SetUserData(channel, userdata);
	FMOD_Channel_SetCallback(channel, &SND_FMOD_Callback);

	// 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, 0.2f), 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)
{
	soundslot_t *slot;

	if (!fmod_system)
		return;

	if (entnum < 0 || entnum >= MAX_CHANNELS || entchannel < 0 || entchannel > 7)
		return;

	slot = &entsounds[entnum].slots[entchannel];
	if (slot->channel)
	{
		FMOD_Channel_Stop(slot->channel);
	}
}

void S_StopAllSounds(qboolean clear)
{
	if (!fmod_system)
		return;

	// TODO Use this to remove per-entity channel group and clear all userdata? => should already be handled by Stop (but double check!)

	FMOD_ChannelGroup_Stop(sfx_channelGroup);

	if (clear)
		S_ClearBuffer();
}

void S_ClearBuffer(void)
{
	// This is meant to prevent the same sound buffer playing over and over while the game is stalled
	// I don't think that's really an issue with FMOD
}

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;

	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)
{
	// Move the sound data up into the CPU cache
	// Not really necessary here
}

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