/*
===========================================================================

IceTech GPL Source Code
Copyright (C) 2026 Justin Marshall

This file is part of the IceTech GPL Source Code.

===========================================================================
*/

#include "precompiled.h"
#pragma hdrstop

#include "MinigameHost.h"
#include "../renderer/RenderSystem.h"

idMinigameInstance::idMinigameInstance() {
	moduleHandle = 0;
	memset( &exports, 0, sizeof( exports ) );
	memset( &imports, 0, sizeof( imports ) );
	instance = NULL;
	memset( &threadInfo, 0, sizeof( threadInfo ) );
	InitializeCriticalSection( &criticalSection );
	threadStarted = false;
	shutdownRequested = false;
	active = false;
	activeSent = false;
	failed = false;
	frameReady = false;
	framebuffer = NULL;
	framebufferWidth = 0;
	framebufferHeight = 0;
	framebufferBytes = 0;
}

idMinigameInstance::~idMinigameInstance() {
	Shutdown();
	DeleteCriticalSection( &criticalSection );
}

void idMinigameInstance::Lock() {
	EnterCriticalSection( &criticalSection );
}

void idMinigameInstance::Unlock() {
	LeaveCriticalSection( &criticalSection );
}

void idMinigameInstance::PrintCallback( void *userData, const char *text ) {
	if ( text && text[0] ) {
		common->Printf( "minigame: %s", text );
	}
}

void idMinigameInstance::SubmitAudioCallback( void *userData, const iceMinigameAudioBuffer_t *audio ) {
	idMinigameInstance *self = reinterpret_cast<idMinigameInstance *>( userData );
	if ( !self || !audio || !audio->samples || audio->frames <= 0 ) {
		return;
	}

	// The ABI already carries raw PCM across the DLL boundary. The engine mixer
	// bridge will consume this callback once the minigame sound emitter lands.
}

bool idMinigameInstance::Start( const char *module, const char *image, const char *cmdLine ) {
	Shutdown();

	if ( !module || !module[0] || !image || !image[0] ) {
		failed = true;
		return false;
	}

	moduleName = module;
	imageName = image;
	commandLine = cmdLine ? cmdLine : "";
	failed = false;
	shutdownRequested = false;

	idStr relativePath;
	if ( moduleName.Find( "/" ) >= 0 || moduleName.Find( "\\" ) >= 0 ) {
		relativePath = moduleName;
	} else {
		relativePath = "minigames/";
		relativePath += moduleName;
	}
	if ( relativePath.Find( "." ) < 0 ) {
		relativePath += ".minigame";
	}

	resolvedPath = fileSystem->RelativePathToOSPath( relativePath.c_str(), "fs_basepath" );
	moduleHandle = Sys_DLL_Load( resolvedPath.c_str() );
	if ( !moduleHandle ) {
		common->Warning( "Could not load minigame '%s' from '%s'", moduleName.c_str(), resolvedPath.c_str() );
		failed = true;
		return false;
	}

	iceMinigameGetAPI_t GetMinigameAPI = (iceMinigameGetAPI_t)Sys_DLL_GetProcAddress( moduleHandle, ICE_MINIGAME_ENTRY_POINT );
	if ( !GetMinigameAPI ) {
		common->Warning( "Minigame '%s' does not export %s", moduleName.c_str(), ICE_MINIGAME_ENTRY_POINT );
		Shutdown();
		failed = true;
		return false;
	}

	imports.version = ICE_MINIGAME_API_VERSION;
	imports.userData = this;
	importBasePath = fileSystem->RelativePathToOSPath( "", "fs_basepath" );
	importSavePath = fileSystem->RelativePathToOSPath( "", "fs_savepath" );
	imports.basePath = importBasePath.c_str();
	imports.savePath = importSavePath.c_str();
	imports.Print = PrintCallback;
	imports.SubmitAudio = SubmitAudioCallback;

	if ( !GetMinigameAPI( &imports, &exports ) || exports.version != ICE_MINIGAME_API_VERSION ||
		 !exports.CreateInstance || !exports.DestroyInstance || !exports.RunFrame || !exports.GetFramebuffer ) {
		common->Warning( "Minigame '%s' has an incompatible API", moduleName.c_str() );
		Shutdown();
		failed = true;
		return false;
	}

	if ( !exports.CreateInstance( &imports, commandLine.c_str(), &instance ) || !instance ) {
		common->Warning( "Minigame '%s' failed to create an instance", moduleName.c_str() );
		Shutdown();
		failed = true;
		return false;
	}

	if ( renderSystem && exports.framebufferWidth > 0 && exports.framebufferHeight > 0 ) {
		renderSystem->CreateScratchImage( imageName.c_str(), exports.framebufferWidth, exports.framebufferHeight );
	}

	Sys_CreateThread( ThreadProc, this, THREAD_NORMAL, threadInfo, "minigame", g_threads, &g_thread_count );
	threadStarted = true;
	return true;
}

void idMinigameInstance::Shutdown() {
	shutdownRequested = true;
	if ( threadStarted && threadInfo.threadHandle ) {
		Sys_DestroyThread( threadInfo );
	}
	threadStarted = false;
	shutdownRequested = false;

	if ( exports.DestroyInstance && instance ) {
		exports.DestroyInstance( instance );
	}
	instance = NULL;

	if ( moduleHandle ) {
		Sys_DLL_Unload( moduleHandle );
	}
	moduleHandle = 0;
	memset( &exports, 0, sizeof( exports ) );

	Lock();
	pendingEvents.Clear();
	ClearFramebuffer();
	frameReady = false;
	active = false;
	activeSent = false;
	Unlock();
}

void idMinigameInstance::SetActive( bool setActive ) {
	Lock();
	active = setActive;
	Unlock();
}

void idMinigameInstance::QueueEvent( const sysEvent_t *event, int time ) {
	if ( !event || !instance ) {
		return;
	}

	iceMinigameInputEvent_t minigameEvent;
	minigameEvent.type = ICE_MINIGAME_EVENT_NONE;
	minigameEvent.value = event->evValue;
	minigameEvent.value2 = event->evValue2;
	minigameEvent.time = time;

	switch ( event->evType ) {
		case SE_KEY:
			minigameEvent.type = ICE_MINIGAME_EVENT_KEY;
			break;
		case SE_CHAR:
			minigameEvent.type = ICE_MINIGAME_EVENT_CHAR;
			break;
		case SE_MOUSE:
			minigameEvent.type = ICE_MINIGAME_EVENT_MOUSE;
			break;
		default:
			return;
	}

	Lock();
	if ( pendingEvents.Num() < 256 ) {
		pendingEvents.Append( minigameEvent );
	}
	Unlock();
}

bool idMinigameInstance::UploadFramebuffer() {
	if ( !renderSystem || !instance ) {
		return false;
	}

	Lock();
	if ( !frameReady || !framebuffer || framebufferWidth <= 0 || framebufferHeight <= 0 ) {
		Unlock();
		return false;
	}
	const bool uploaded = renderSystem->UploadImage( imageName.c_str(), framebuffer, framebufferWidth, framebufferHeight );
	frameReady = false;
	Unlock();
	return uploaded;
}

unsigned int idMinigameInstance::ThreadProc( void *parm ) {
	idMinigameInstance *self = reinterpret_cast<idMinigameInstance *>( parm );
	return self ? self->RunThread() : 0;
}

unsigned int idMinigameInstance::RunThread() {
	int lastTime = Sys_Milliseconds();

	while ( !shutdownRequested ) {
		iceMinigameInputEvent_t events[256];
		int numEvents = 0;
		bool nowActive;
		bool sendActive;

		Lock();
		nowActive = active;
		sendActive = ( activeSent != active );
		activeSent = active;
		numEvents = pendingEvents.Num();
		if ( numEvents > 256 ) {
			numEvents = 256;
		}
		for ( int i = 0; i < numEvents; i++ ) {
			events[i] = pendingEvents[i];
		}
		pendingEvents.Clear();
		Unlock();

		if ( sendActive && exports.SetActive ) {
			exports.SetActive( instance, nowActive ? 1 : 0 );
		}

		for ( int i = 0; i < numEvents; i++ ) {
			if ( exports.QueueEvent ) {
				exports.QueueEvent( instance, &events[i] );
			}
		}

		const int now = Sys_Milliseconds();
		const int elapsed = Max( 1, now - lastTime );
		lastTime = now;

		if ( nowActive || numEvents > 0 ) {
			exports.RunFrame( instance, elapsed );

			iceMinigameFramebuffer_t framebufferInfo;
			memset( &framebufferInfo, 0, sizeof( framebufferInfo ) );
			if ( exports.GetFramebuffer( instance, &framebufferInfo ) ) {
				CopyFramebuffer( framebufferInfo );
			}
		}

		Sys_Sleep( 1 );
	}

	return 0;
}

void idMinigameInstance::CopyFramebuffer( const iceMinigameFramebuffer_t &source ) {
	if ( !source.pixels || source.width <= 0 || source.height <= 0 || source.pitchBytes <= 0 ||
		 source.pixelFormat != ICE_MINIGAME_PIXEL_RGBA8 ) {
		return;
	}

	const int rowBytes = source.width * 4;
	const int requiredBytes = rowBytes * source.height;

	Lock();
	if ( requiredBytes != framebufferBytes ) {
		ClearFramebuffer();
		framebuffer = (byte *)Mem_Alloc( requiredBytes );
		framebufferBytes = requiredBytes;
	}

	if ( framebuffer ) {
		for ( int y = 0; y < source.height; y++ ) {
			memcpy( framebuffer + y * rowBytes, source.pixels + y * source.pitchBytes, rowBytes );
		}
		framebufferWidth = source.width;
		framebufferHeight = source.height;
		frameReady = true;
	}
	Unlock();
}

void idMinigameInstance::ClearFramebuffer() {
	if ( framebuffer ) {
		Mem_Free( framebuffer );
	}
	framebuffer = NULL;
	framebufferWidth = 0;
	framebufferHeight = 0;
	framebufferBytes = 0;
}