#include "Misc/AutomationTest.h"
#include "Telemetry/TelemetryEvent.h"
#include "Telemetry/TelemetryEvents.h"
#include "Telemetry/TelemetrySink.h"
#include "Dom/JsonObject.h"
#include "Serialization/JsonSerializer.h"
#include "Serialization/JsonReader.h"
#include "HAL/FileManager.h"
#include "Misc/FileHelper.h"
#include "Misc/Paths.h"

#if WITH_DEV_AUTOMATION_TESTS

namespace
{
	FTelemetryEnvelope MakeEnvelope()
	{
		FTelemetryEnvelope Envelope;
		Envelope.EventId = FGuid::NewGuid();
		Envelope.TimestampUtc = FDateTime::UtcNow();
		Envelope.GameTime = 12.5f;
		Envelope.SessionId = FGuid::NewGuid();
		Envelope.PlayerId = TEXT("abc123");
		Envelope.bIsServer = true;
		Envelope.PartySize = 2;
		Envelope.Build = TEXT("test+deadbeef");
		Envelope.Map = TEXT("L_Gym");
		Envelope.bCheatsUsed = true;
		return Envelope;
	}

	FString TempJsonlPath()
	{
		return FPaths::ProjectSavedDir() / TEXT("Automation/Telemetry") / FGuid::NewGuid().ToString(EGuidFormats::Digits) + TEXT(".jsonl");
	}

	bool ParseObject(const FString& Line, TSharedPtr<FJsonObject>& OutObject)
	{
		const TSharedRef<TJsonReader<>> Reader = TJsonReaderFactory<>::Create(Line);
		return FJsonSerializer::Deserialize(Reader, OutObject) && OutObject.IsValid();
	}
}

IMPLEMENT_SIMPLE_AUTOMATION_TEST(FTelemetryEnvelopeCarriesEveryFieldTest, "Salty.Core.Telemetry.Envelope.CarriesEveryField",
	EAutomationTestFlags::ProductFilter | EAutomationTestFlags_ApplicationContextMask)

bool FTelemetryEnvelopeCarriesEveryFieldTest::RunTest(const FString& Parameters)
{
	const FTelemetryEnvelope Envelope = MakeEnvelope();
	FTelemetryEvent Event;
	Event.Name = TelemetryEvents::SessionStarted;
	Event.Payload = FTelemetryPayload().Set(TEXT("answer"), 42).Set(TEXT("tag"), TEXT("x"));

	TSharedPtr<FJsonObject> Object;
	if (!TestTrue(TEXT("the line parses"), ParseObject(Telemetry::ToJsonLine(Envelope, Event), Object)))
	{
		return false;
	}

	TestEqual(TEXT("schema_version"), static_cast<int32>(Object->GetNumberField(TEXT("schema_version"))), Envelope.SchemaVersion);
	TestEqual(TEXT("event_id"), Object->GetStringField(TEXT("event_id")), Envelope.EventId.ToString(EGuidFormats::DigitsWithHyphensLower));
	TestEqual(TEXT("timestamp_utc"), Object->GetStringField(TEXT("timestamp_utc")), Envelope.TimestampUtc.ToIso8601());
	TestEqual(TEXT("game_time"), static_cast<float>(Object->GetNumberField(TEXT("game_time"))), Envelope.GameTime);
	TestEqual(TEXT("session_id"), Object->GetStringField(TEXT("session_id")), Envelope.SessionId.ToString(EGuidFormats::DigitsWithHyphensLower));
	TestEqual(TEXT("player_id"), Object->GetStringField(TEXT("player_id")), Envelope.PlayerId);
	TestEqual(TEXT("is_server"), Object->GetBoolField(TEXT("is_server")), Envelope.bIsServer);
	TestEqual(TEXT("party_size"), static_cast<int32>(Object->GetNumberField(TEXT("party_size"))), Envelope.PartySize);
	TestEqual(TEXT("build"), Object->GetStringField(TEXT("build")), Envelope.Build);
	TestEqual(TEXT("map"), Object->GetStringField(TEXT("map")), Envelope.Map);
	TestEqual(TEXT("cheats_used"), Object->GetBoolField(TEXT("cheats_used")), Envelope.bCheatsUsed);
	TestEqual(TEXT("name"), Object->GetStringField(TEXT("name")), TelemetryEvents::SessionStarted.ToString());
	TestEqual(TEXT("payload.answer"), static_cast<int32>(Object->GetObjectField(TEXT("payload"))->GetNumberField(TEXT("answer"))), 42);
	TestEqual(TEXT("payload.tag"), Object->GetObjectField(TEXT("payload"))->GetStringField(TEXT("tag")), FString(TEXT("x")));
	return true;
}

IMPLEMENT_SIMPLE_AUTOMATION_TEST(FTelemetryEventNoPayloadTest, "Salty.Core.Telemetry.Event.NoPayloadIsEmptyObject",
	EAutomationTestFlags::ProductFilter | EAutomationTestFlags_ApplicationContextMask)

bool FTelemetryEventNoPayloadTest::RunTest(const FString& Parameters)
{
	FTelemetryEvent Event;
	Event.Name = TelemetryEvents::AppStarted;
	const FString Line = Telemetry::ToJsonLine(MakeEnvelope(), Event);

	TSharedPtr<FJsonObject> Object;
	if (!TestTrue(TEXT("the line parses"), ParseObject(Line, Object)))
	{
		return false;
	}
	const TSharedPtr<FJsonObject>* Payload = nullptr;
	TestTrue(TEXT("payload is an object"), Object->TryGetObjectField(TEXT("payload"), Payload));
	TestTrue(TEXT("payload is empty"), Payload && (*Payload)->Values.Num() == 0);
	TestTrue(TEXT("the line is a single line"), !Line.Contains(TEXT("\n")));
	return true;
}

IMPLEMENT_SIMPLE_AUTOMATION_TEST(FTelemetryJsonlOneLinePerEventTest, "Salty.Core.Telemetry.Jsonl.OneValidLinePerEvent",
	EAutomationTestFlags::ProductFilter | EAutomationTestFlags_ApplicationContextMask)

bool FTelemetryJsonlOneLinePerEventTest::RunTest(const FString& Parameters)
{
	const FString Path = TempJsonlPath();
	constexpr int32 Count = 25;
	{
		FJsonlTelemetrySink Sink(Path, /*DrainIntervalSeconds*/ 3600.0);
		for (int32 Index = 0; Index < Count; ++Index)
		{
			FTelemetryEvent Event;
			Event.Name = TelemetryEvents::CheatUsed;
			Event.Payload = FTelemetryPayload().Set(TEXT("index"), Index);
			Sink.Emit(MakeEnvelope(), Event);
		}
		Sink.Flush();
	}

	TArray<FString> Lines;
	TestTrue(TEXT("the file exists after Flush"), FFileHelper::LoadFileToStringArray(Lines, *Path));
	TestEqual(TEXT("one line per event"), Lines.Num(), Count);
	for (int32 Index = 0; Index < Lines.Num(); ++Index)
	{
		TSharedPtr<FJsonObject> Object;
		if (!TestTrue(FString::Printf(TEXT("line %d parses"), Index), ParseObject(Lines[Index], Object)))
		{
			continue;
		}
		TestEqual(FString::Printf(TEXT("line %d is in order"), Index), static_cast<int32>(Object->GetObjectField(TEXT("payload"))->GetNumberField(TEXT("index"))), Index);
	}
	IFileManager::Get().Delete(*Path);
	return true;
}

IMPLEMENT_SIMPLE_AUTOMATION_TEST(FTelemetryJsonlEmitDoesNotTouchFileTest, "Salty.Core.Telemetry.Jsonl.EmitDoesNotTouchTheFile",
	EAutomationTestFlags::ProductFilter | EAutomationTestFlags_ApplicationContextMask)

bool FTelemetryJsonlEmitDoesNotTouchFileTest::RunTest(const FString& Parameters)
{
	// The rule is "never blocks the caller longer than building the object". The observable form of that rule:
	// Emit does no file work at all; only the worker's drain (here deferred by the interval) or Flush writes.
	const FString Path = TempJsonlPath();
	{
		FJsonlTelemetrySink Sink(Path, /*DrainIntervalSeconds*/ 3600.0);
		FTelemetryEvent Event;
		Event.Name = TelemetryEvents::AppStarted;
		Sink.Emit(MakeEnvelope(), Event);
		TestFalse(TEXT("no file after Emit alone"), IFileManager::Get().FileExists(*Path));
		Sink.Flush();
		TestTrue(TEXT("the file exists after Flush"), IFileManager::Get().FileExists(*Path));
	}
	IFileManager::Get().Delete(*Path);
	return true;
}

#endif