// 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
#	undef _WINSOCK_DEPRECATED_NO_WARNINGS
#	include <zencore/trace.h>

#	include <zencore/memory/fmalloc.h>
#	include <zencore/memory/memorytrace.h>

namespace zen {

void
TraceConfigure(const TraceOptions& Options)
{
	// Configure channels based on command line options

	using namespace std::literals;

	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); };

	if (Options.Channels.empty())
	{
		ProcessTraceArg("default"sv);
	}
	else
	{
		ProcessChannelList(Options.Channels);
	}

	if (Options.Host.size())
	{
		trace::SendTo(Options.Host.c_str());
	}
	else if (Options.File.size())
	{
		trace::WriteTo(Options.File.c_str());
	}

#	if ZEN_WITH_MEMTRACK
	FMalloc* TraceMalloc = MemoryTrace_Create(GMalloc, Options);
	if (TraceMalloc != GMalloc)
	{
		GMalloc = TraceMalloc;
		MemoryTrace_Initialize();
	}
#	endif
}

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();
	});
}

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

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

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

bool
GetTraceOptionsFromCommandline(TraceOptions& OutOptions)
{
	bool HasOptions = false;

#	if ZEN_WITH_TRACE
	using namespace std::literals;

	auto MatchesArg = [](std::string_view Option, std::string_view Arg) -> std::optional<std::string_view> {
		if (Arg.starts_with(Option))
		{
			std::string_view::value_type DelimChar = Arg[Option.length()];
			if (DelimChar == ' ' || DelimChar == '=')
			{
				return Arg.substr(Option.size() + 1);
			}
		}
		return {};
	};

	constexpr std::string_view TraceOption	   = "--trace"sv;
	constexpr std::string_view TraceHostOption = "--tracehost"sv;
	constexpr std::string_view TraceFileOption = "--tracefile"sv;

	std::function<void(const std::string_view&)> ProcessArg = [&](const std::string_view& Arg) {
		if (auto Host = MatchesArg(TraceHostOption, Arg); Host.has_value())
		{
			OutOptions.Host = Host.value();
			HasOptions		= true;
		}
		else if (auto File = MatchesArg(TraceFileOption, Arg); File.has_value())
		{
			OutOptions.File = File.value();
			HasOptions		= true;
		}
		else if (auto Channels = MatchesArg(TraceOption, Arg); Channels.has_value())
		{
			if (!OutOptions.Channels.empty())
			{
				OutOptions.Channels = ","sv;
			}
			OutOptions.Channels += Channels.value();
			HasOptions = true;
		}
	};

	IterateCommandlineArgs(ProcessArg);
#	endif	// ZEN_WITH_TRACE
	return HasOptions;
}

}  // namespace zen

#endif	// ZEN_WITH_TRACE