#pragma region License
/*
License (OLC-3)
~~~~~~~~~~~~~~~

Copyright 2024 Joshua Sigona <sigonasr2@gmail.com>

Redistribution and use in source and binary forms, with or without modification,
are permitted provided that the following conditions are met:

1. Redistributions or derivations of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.

2. Redistributions or derivative works in binary form must reproduce the above
copyright notice. This list of conditions and the following	disclaimer must be
reproduced in the documentation and/or other materials provided with the distribution.

3. Neither the name of the copyright holder nor the names of its contributors may
be used to endorse or promote products derived from this software without specific
prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS	"AS IS" AND ANY
EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
SHALL THE COPYRIGHT	HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
INCIDENTAL,	SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
CONTRACT, STRICT LIABILITY, OR TORT	(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
SUCH DAMAGE.

Portions of this software are copyright © 2024 The FreeType
Project (www.freetype.org). Please see LICENSE_FT.txt for more information.
All rights reserved.
*/
#pragma endregion
#include "Audio.h"
#include "AdventuresInLestoria.h"
#include "DEFINES.h"
#include "util.h"
#include "LoadingScreen.h"
#include "Menu.h"

INCLUDE_game
INCLUDE_DATA

float Audio::defaultFadeTime=0.f;
float Audio::sfxVol=1.f;
float Audio::bgmVol=1.f;
bool Audio::muted=false;

void Audio::Initialize(){
	Engine().SetBackgroundPlay(true);
	Self().events.insert("Default Volume");
	for(auto&[key,data]:DATA["Events"]){
		if(key!="SFX"){ //HACK ALERT! We are specifically excluding the SFX key because it's used to specify the sound effects in-game.
			Self().events.insert(key);
		}
	}
	for(auto&[songFileName,size]:DATA["BGM"]){
		auto&data=DATA["BGM"][songFileName];
		if(songFileName!="Default Fade Time"){
			int channelCounter=0;

			BGM&bgm=Self().bgm[songFileName];

			bgm.SetFileName(songFileName);
			bgm.SetName(data["Track Name"].GetString());

			while(data.HasProperty(std::format("channel[{}]",channelCounter))){
				std::string channelName=data[std::format("channel[{}]",channelCounter)].GetString();
				if(!std::filesystem::exists("bgm_directory"_S+channelName))ERR(std::format("WARNING! Could not load file {} for track {}",channelName,songFileName));
				bgm.AddChannel(channelName);
				channelCounter++;
			}

			if(!data["Events"].HasProperty("Default Volume"))ERR(std::format("WARNING! Track {} does not have a Default Volume parameter!",bgm.GetName()));

			if(data.HasProperty("Fade Time")){
				bgm.SetFadeTime(data["Fade Time"].GetReal());
			}else{
				bgm.SetFadeTime(defaultFadeTime);
			}

			if(data.HasProperty("Loop Repeat Start Point")){
				bgm.SetLoopStartTime(data["Loop Repeat Start Point"].GetReal());
			}

			if(data.HasProperty("Events")){
				for(auto&eventName:Self().events){
					auto&eventData=data["Events"][eventName];

					if(eventData.GetValueCount()==0){ //We assume we'll inherit from the default volume instead.
						VolumeList volumes;
						for(int i=0;i<eventData.GetValueCount();i++){
							volumes.push_back(data["Events"]["Default Volume"].GetInt(i)/100.f);
						}
						bgm.AddEventVolumes(eventName,volumes);
					}else{
						if(eventData.GetValueCount()!=bgm.GetChannelCount())ERR(std::format("WARNING! {} parameters do not match channel count. {} != {}",eventName,eventData.GetValueCount(),bgm.GetChannelCount()));
						VolumeList volumes;
						for(int i=0;i<eventData.GetValueCount();i++){
							volumes.push_back(eventData.GetInt(i)/100.f);
						}
						bgm.AddEventVolumes(eventName,volumes);
					}
				}
			}
		}else{
			defaultFadeTime=data.GetReal();
		}
	}

	Self().bgm.SetInitialized();
}

MiniAudio&Audio::Engine(){
	return game->audioEngine.audioEngine;
}
void Audio::Play(const std::string_view sound){
	Engine().Play(std::string(sound));
};
const size_t Audio::LoadAndPlay(const std::string_view sound,const bool loop){
	size_t soundID=Engine().LoadSound(std::string(sound));
	Engine().Play(soundID,loop);
	return soundID;
};
void Audio::PrepareBGM(const std::string_view sound,const bool loop){
	BGM&track=Self().bgm[std::string(sound)];
	Self().fullyLoaded=false;
	StopBGM(); //Stop any currently playing track.
	Self().playParams={std::string(sound),loop};
	Self().playBGMWaitTime=0.7f;
	#pragma region Internal Loading Loop Setup
		Self().trackLoadStarted=false;
		Self().trackLoadComplete=false;
		Self().channelPlayingStarted=false;
		Self().channelPlayingComplete=false;
		int currentLoopIndex=0;
	#pragma endregion
	Self().immediatelyLoadAudio=false;
};

void Audio::StopBGM(){
	if(Self().BGMIsPlaying()){
		BGM&currentTrack=Self().bgm[Self().currentBGM];
		for(int trackID:currentTrack.GetChannelIDs()){
			Engine().SetVolume(trackID,0.f);
		}
		for(int trackID:currentTrack.GetChannelIDs()){
			Engine().Stop(trackID);
		}
	}
}

const bool Audio::BGMIsPlaying(){
	return Self().currentBGM.length()>0;
}

const Volume&Audio::BGM::GetVolume(const Event&eventName,const int&index)const{
	return eventVolumes.GetVolumes(eventName).at(index);
}

void Audio::BGM::Load(){
	if(!Self().trackLoadStarted){
		Self().trackLoadStarted=true;
		if(Self().BGMIsPlaying()){
			if(Self().GetTrackName()==songFileName){ //We are already playing the current track.
				Self().trackLoadComplete=Self().channelPlayingComplete=Self().fullyLoaded=true;
				return;
			}else{
				BGM&bgm=Self().bgm[Self().GetTrackName()];
				if(Self().BGMIsPlaying()){
					bgm.Unload();
				}
			}
		}
		Self().currentBGM=songFileName;
		Self().currentLoopIndex=0;
		Self().lastTimestamp=0.f;
		BGM&newBgm=Self().bgm[songFileName];
		if(newBgm.channels.size()>0)ERR(std::format("WARNING! The size of the channels list is greater than zero! Size: {}",newBgm.channels.size()));
	}else{
		BGM&newBgm=Self().bgm[songFileName];
		const ChannelName&channel=newBgm.GetChannels()[Self().currentLoopIndex];
		ChannelID soundID=Engine().LoadSound("bgm_directory"_S+channel);
		newBgm.channels.push_back(soundID);
		#pragma region Handle threaded loop indexing
			Self().currentLoopIndex++;
			if(Self().currentLoopIndex>=newBgm.GetChannels().size()){
				Self().trackLoadComplete=true;
			}
		#pragma endregion
	}
}

void Audio::BGM::Unload(){
	BGM&bgm=Self().bgm[Self().currentBGM];
	for(const ChannelID&id:channels){
		Engine().UnloadSound(id);
	}
	channels.clear();
	Self().currentBGM="";
}

const ChannelID&Audio::BGM::GetChannelID(const int index){
	return channels[index];
}

const ChannelIDList&Audio::BGM::GetChannelIDs()const{
	return channels;
}

const std::vector<ChannelName>&Audio::BGM::GetChannels()const{
	return channelNames;
}

void Audio::BGM::SetFadeTime(const float fadeTime){
	this->fadeTime=fadeTime;
}

void Audio::BGM::AddEventVolumes(const Event&eventName,const VolumeList&volumes){
	eventVolumes.AddEventInfo(eventName,volumes);
}

const size_t Audio::BGM::GetChannelCount()const{
	return channelNames.size();
}

const SongName&Audio::BGM::GetName()const{
	return songName;
}

void Audio::BGM::SetName(std::string_view name){
	songName=name;
}

void Audio::BGM::SetFileName(std::string_view name){
	songFileName=name;
}

void Audio::BGM::AddChannel(const ChannelName&name){
	channelNames.push_back(name);
}

const VolumeList&Audio::EventData::GetVolumes(const Event&event)const{
	if(eventInfo.find(event)!=eventInfo.end()&&eventInfo.at(event).size()>0)return eventInfo.at(event);
	return eventInfo.at("Default Volume");
}

void Audio::EventData::AddEventInfo(const Event&eventName,const VolumeList&volumes){
	eventInfo[eventName]=volumes;
}

Audio&Audio::Self(){
	return game->audioEngine;
}

const Event&Audio::GetAudioEvent(){
	return Self().currentAudioEvent;
}
void Audio::SetAudioEvent(const Event&eventName){
	if(Self().events.find(eventName)==Self().events.end())ERR(std::format("WARNING! cannot find event {}",eventName));

	Self().currentAudioEvent=eventName;
	
	if(Audio::BGMIsPlaying()){
		BGM&currentBgm=Self().bgm[Self().currentBGM];

		Self().targetVolumes.clear();

		Self().fadeToTargetVolumeTime=currentBgm.GetFadeTime();
		for(int currentTrackIndex=0;int trackID:currentBgm.GetChannelIDs()){
			//Engine().SetVolume(trackID,currentBgm.GetVolume(eventName,currentTrackIndex));
			Self().targetVolumes.push_back(currentBgm.GetVolume(eventName,currentTrackIndex)); //Set the target volumes so that the engine can gradually move the volumes over to the new settings.
			currentTrackIndex++;
		}
	}
}

std::string operator""_SFX(const char*key,size_t length){
	return "sfx_directory"_S+std::string(key,length);
}

const SongName&Audio::GetTrackName(){
	return Self().currentBGM;
}

void Audio::UpdateLoop(){
	if(Self().playBGMWaitTime==0.f){
		BGM&track=Self().bgm[Self().playParams.sound];
		if(!Self().trackLoadComplete){
			track.Load();
		}else
		if(!Self().channelPlayingComplete){
			if(!Self().channelPlayingStarted){
				Self().prevVolumes.clear();
				Self().targetVolumes.clear();
				Self().fadeToTargetVolumeTime=0.f;
				Self().currentLoopIndex=0;
				Self().channelPlayingStarted=true;
			}else{
				int trackID=track.GetChannelIDs()[Self().currentLoopIndex];
				float channelVol=track.GetVolume(Self().currentAudioEvent,Self().currentLoopIndex);
				Self().prevVolumes.push_back(channelVol);
				Self().targetVolumes.push_back(channelVol);
				Engine().SetVolume(trackID,Self().GetCalculatedBGMVolume(channelVol));
				#pragma region Handle threaded loop indexing
					Self().currentLoopIndex++;
					if(Self().currentLoopIndex>=track.GetChannelIDs().size()){
						Self().channelPlayingComplete=true;
						Self().fullyLoaded=true;
					}
				#pragma endregion
			}
		}else
		if(!Self().fullyLoaded){
			ERR("Invalid loading state or too many calls to initialize audio loop! The audio is still not fully loaded!");
		}
	}
}

void Audio::PlayBGM(const std::string_view sound,const bool loop){
	PrepareBGM(sound,loop);
	Self().immediatelyLoadAudio=true;
}

void Audio::Update(){
	if(Self().BGMFullyLoaded()&&Self().BGMIsPlaying()){
		Audio::BGM&track=Self().bgm[Self().GetTrackName()];
		float currentTimestamp{Engine().GetCursorMilliseconds(track.GetChannelIDs()[0])/1000.f};
		if(Self().lastTimestamp>currentTimestamp){
			for(int trackID:track.GetChannelIDs()){
				Engine().Seek(trackID,unsigned long long(track.GetLoopStartTime())*1000);
			}
			currentTimestamp=Engine().GetCursorMilliseconds(track.GetChannelIDs()[0])/1000.f; //Update to new timestamp now that it's been shifted over.
		}
		Self().lastTimestamp=currentTimestamp;
	}else{
		if(Self().fadeToTargetVolumeTime==0.f&&Self().playBGMWaitTime>0.f){
			Self().playBGMWaitTime=std::max(Self().playBGMWaitTime-game->GetElapsedTime(),0.f);
			if(Self().playBGMWaitTime==0.f&&Self().immediatelyLoadAudio){
				while(!Self().BGMFullyLoaded()){
					UpdateLoop(); //We immediately load the file. In a loading screen setting we would defer UpdateLoop() such that we have extra time to update the screen, UpdateLoop() is divided into many parts of the music loading process.
				}

				//Start playing the tracks and setup a callback to repeat at looped time.
				Audio::BGM&track=Self().bgm[Self().GetTrackName()];
				for(int trackID:track.GetChannelIDs()){
					Engine().Play(trackID,true);
				}
			}
		}
		if(Self().fadeToTargetVolumeTime>0.f){
			Self().fadeToTargetVolumeTime=std::max(0.f,Self().fadeToTargetVolumeTime-game->GetElapsedTime());
			for(int counter=0;float&vol:Self().prevVolumes){
				const BGM&currentBgm=Self().bgm[Self().currentBGM];
				Engine().SetVolume(currentBgm.GetChannelIDs()[counter],util::lerp(Self().GetCalculatedBGMVolume(vol),Self().GetCalculatedBGMVolume(Self().targetVolumes[counter]),1-(Self().fadeToTargetVolumeTime/currentBgm.GetFadeTime())));
				counter++;
			}
		}
	}
}

const bool Audio::BGMFullyLoaded(){
	return Self().fullyLoaded;
}

const float&Audio::BGM::GetFadeTime()const{
	return fadeTime;
}

const float&Audio::BGM::GetLoopStartTime()const{
	return loopStartTime;
}

void Audio::SetBGMVolume(float vol){
	bgmVol=vol;
	UpdateBGMVolume();
}
void Audio::SetBGMPitch(float pitch){
	BGM&track=Self().bgm[Self().playParams.sound];
	for(int channelListIndex=0;int trackID:track.GetChannelIDs()){
		Engine().SetPitch(trackID,pitch);
		channelListIndex++;
	}
}
void Audio::SetSFXVolume(float vol){
	sfxVol=vol;
}
float&Audio::GetBGMVolume(){
	return bgmVol;
}
float&Audio::GetSFXVolume(){
	return sfxVol;
}
void Audio::UpdateBGMVolume(){
	BGM&track=Self().bgm[Self().playParams.sound];
	for(int channelListIndex=0;int trackID:track.GetChannelIDs()){
		float channelVol=track.GetVolume(Self().currentAudioEvent,channelListIndex);
		Engine().SetVolume(trackID,Self().GetCalculatedBGMVolume(channelVol));
		channelListIndex++;
	}
	EnvironmentalAudio::UpdateEnvironmentalAudio();
}
float Audio::GetCalculatedBGMVolume(const float channelVol){
	float pauseMult=1.f;
	if(Menu::IsMenuOpen()&&Menu::stack.front()==Menu::menus[MenuType::PAUSE]){
		pauseMult=0.5f;
	}
	return channelVol*GetBGMVolume()*GetMuteMult()*pauseMult;
}
float Audio::GetCalculatedSFXVolume(const float vol){
	return vol*GetSFXVolume()*GetMuteMult();
}
float Audio::GetMuteMult(){
	if(muted)return 0.f;
	return 1.f;
}

int Audio::GetPrepareBGMLoopIterations(std::string_view sound){
	BGM&newBgm=Self().bgm[std::string(sound)];
	return newBgm.GetChannels().size()*2+2; //The channels list gets populated by calling newBgm.Load(), which then provides the list of channels that need to be loaded and played. This is why we multiply by 2. Each of the loading phases also consist of an initialization phase, so we add 2 as well.
}

void Audio::BGM::SetLoopStartTime(const float loopStartTime){
	this->loopStartTime=loopStartTime;
}