// Copyright Epic Games, Inc. All Rights Reserved.

#include <transportplugin.h>
#include <atomic>
#include <cstring>
#include <cstdlib>
#include <cstdio>

extern "C"
{
	typedef void (*LogCallback)(void* UsrPtr, int32_t Level, const char* Buffer);

	// native -> managed API
	void StartAndroidPortForwarder(LogCallback Callback, void* UsrPtr, const char* ADBExecutable, uint32_t Port);
	void StopAndroidPortForwarder();
}

class ZenServerAdapter : public zen::TransportPlugin
{
public:
	ZenServerAdapter(zen::TransportLogger* InLogger)
		: Logger(InLogger)
	{
	}
	virtual ~ZenServerAdapter() = default;

	uint32_t AddRef() const override
	{
		return const_cast<ZenServerAdapter*>(this)->ReferenceCount.fetch_add(1) + 1;
	}

	uint32_t Release() const override
	{
		const uint32_t RefCount = const_cast<ZenServerAdapter*>(this)->ReferenceCount.fetch_sub(1);
		if (RefCount <= 1)
		{
			delete this;
		}
		return RefCount - 1;
	}

	void Configure(const char* OptionTag, const char* OptionValue) override
	{
		if (!strcmp(OptionTag, "port"))
		{
			char* EndPtr = nullptr;
			const long PortValue = strtoul(OptionValue, &EndPtr, 10);
			if (OptionValue != EndPtr)
			{
				Port = (uint32_t)PortValue;
			}
			else
			{
				Logger->LogMessage(zen::TransportLogger::LogLevel::Err, "Can't parse port value");
			}
		}
		else if (!strcmp(OptionTag, "adb_executable"))
		{
			snprintf(ADBExecutable, sizeof(ADBExecutable), "%s", OptionValue);
		}
	}

	void Initialize(zen::TransportServer* ServerInterface) override
	{
		StartAndroidPortForwarder(
		[](void* ThisPtr, int32_t Level, const char* Buffer)
		{
			static_cast<ZenServerAdapter*>(ThisPtr)->Logger->LogMessage(Level == 1 ? zen::TransportLogger::LogLevel::Err : zen::TransportLogger::LogLevel::Info, Buffer);
		},
		this, ADBExecutable, Port);
	}

	void Shutdown() override
	{
		StopAndroidPortForwarder();
	}

	const char* GetDebugName() override
	{
		return "AndroidPortForwarder";
	}

	bool IsAvailable() override
	{
		return true;
	}

private:
	std::atomic<uint32_t> ReferenceCount = {0};
	uint32_t Port = 8558;
	char ADBExecutable[1024] = {};
	zen::TransportLogger* Logger = nullptr;
};

#if defined(_MSC_VER)
#	define DLL_TRANSPORT_API __declspec(dllexport)
#else
#	define DLL_TRANSPORT_API
#endif

extern "C" DLL_TRANSPORT_API void GetTransportPluginVersion(uint32_t* OutApiVersion, uint32_t* OutPluginVersion)
{
	if (OutApiVersion != nullptr)
	{
		*OutApiVersion = zen::kTransportApiVersion;
	}

	if (OutPluginVersion != nullptr)
	{
		*OutPluginVersion = 2;
	}
}

extern "C" DLL_TRANSPORT_API zen::TransportPlugin* CreateTransportPlugin(zen::TransportLogger* Logger)
{
	return new ZenServerAdapter(Logger);
}