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

#if ZEN_WITH_TRACE

#	include <zencore/config.h>
#	include <zencore/zencore.h>
#	include <zencore/commandline.h>
#	include <zencore/string.h>
#	include <zencore/logging.h>

#	define TRACE_IMPLEMENT 1
#	include <zencore/trace.h>

#	include <zencore/memory/memorytrace.h>

namespace zen {

void
TraceConfigure()
{
	// Configure channels based on command line options

	using namespace std::literals;

	constexpr std::string_view TraceOption = "--trace="sv;

	std::function<void(const std::string_view&)> ProcessChannelList;

	auto ProcessTraceArg = [&](const std::string_view& Arg) {
		if (Arg == "default"sv)
		{
			ProcessChannelList("cpu,log"sv);
		}
		else if (Arg == "memory"sv)
		{
			ProcessChannelList("memtag,memalloc,callstack,module"sv);
		}
		else if (Arg == "memory_light"sv)
		{
			ProcessChannelList("memtag,memalloc"sv);
		}
		else if (Arg == "memtag"sv)
		{
			// memtag actually traces to the memalloc channel
			ProcessChannelList("memalloc"sv);
		}
		else
		{
			// Presume that the argument is a trace channel name

			StringBuilder<128> AnsiChannel;
			AnsiChannel << Arg;

			const bool IsEnabled = trace::ToggleChannel(AnsiChannel.c_str(), true);

			if (IsEnabled == false)
			{
				// Logging here could be iffy, but we might want some other feedback mechanism here
				// to indicate to users that they're not getting what they might be expecting
			}
		}
	};

	ProcessChannelList = [&](const std::string_view& OptionArgs) { IterateCommaSeparatedValue(OptionArgs, ProcessTraceArg); };

	bool TraceOptionPresent = false;

	std::function<void(const std::string_view&)> ProcessArg = [&](const std::string_view& Arg) {
		if (Arg.starts_with(TraceOption))
		{
			const std::string_view OptionArgs = Arg.substr(TraceOption.size());

			TraceOptionPresent = true;

			ProcessChannelList(OptionArgs);
		}
	};

	IterateCommandlineArgs(ProcessArg);

	if (!TraceOptionPresent)
	{
		ProcessTraceArg("default"sv);
	}
}

void
TraceInit(std::string_view ProgramName)
{
	static std::atomic_bool gInited	 = false;
	bool					Expected = false;
	if (!gInited.compare_exchange_strong(Expected, true))
	{
		return;
	}

	trace::FInitializeDesc Desc = {
		.bUseImportantCache = true,
	};
	trace::Initialize(Desc);

#	if ZEN_PLATFORM_WINDOWS
	const char* CommandLineString = GetCommandLineA();
#	else
	const char* CommandLineString = "";
#	endif

	trace::ThreadRegister("main", /* system id */ 0, /* sort id */ 0);
	trace::DescribeSession(ProgramName,
#	if ZEN_BUILD_DEBUG
						   trace::Build::Debug,
#	else
						   trace::Build::Development,
#	endif
						   CommandLineString,
						   ZEN_CFG_VERSION_BUILD_STRING);

	atexit([] {
#	if ZEN_WITH_MEMTRACK
		zen::MemoryTrace_Shutdown();
#	endif
		trace::Update();
		TraceShutdown();
	});

	TraceConfigure();
}

void
TraceShutdown()
{
	(void)TraceStop();
	trace::Shutdown();
}

bool
IsTracing()
{
	return trace::IsTracing();
}

void
TraceStart(std::string_view ProgramName, const char* HostOrPath, TraceType Type)
{
	TraceInit(ProgramName);
	switch (Type)
	{
		case TraceType::Network:
			trace::SendTo(HostOrPath);
			break;

		case TraceType::File:
			trace::WriteTo(HostOrPath);
			break;

		case TraceType::None:
			break;
	}
}

bool
TraceStop()
{
	if (trace::Stop())
	{
		return true;
	}
	return false;
}

}  // namespace zen

#endif	// ZEN_WITH_TRACE