// Headless tests of the stream focus seam (Core/DescentStreamFocus.h).

#include "Tests/DescentTestCommon.h"
#include "Core/DescentMath.h"
#include "Core/DescentStreamFocus.h"

#if WITH_DEV_AUTOMATION_TESTS

IMPLEMENT_SIMPLE_AUTOMATION_TEST(FDescentStreamFocusTest, "Descent.Stream.Focus", DESCENT_TEST_FLAGS)
bool FDescentStreamFocusTest::RunTest(const FString& Parameters)
{
	FDescentTestWorld TW;
	UDescentStreamFocusSubsystem* F = TW.Sub<UDescentStreamFocusSubsystem>();
	if (!TestNotNull(TEXT("the stream focus subsystem exists in a game world"), F))
	{
		return false;
	}

	// A test world has no player, so the default view focus has no point; nothing registered, nothing to stream.
	TArray<FDescentStreamPoint> Points;
	F->GetFocusPoints(Points);
	TestEqual(TEXT("no player and nothing registered: no points"), Points.Num(), 0);
	TestTrue(TEXT("the view location is part of the default"), F->GetUseViewLocation());
	FDescentStreamPoint View;
	TestFalse(TEXT("there is no view point without a player controller"), F->GetViewPoint(View));

	// Registered points, ordered by owner name whatever the registration order, with their radii.
	const FDescentHandle HB = F->RegisterFocus(TEXT("Beacon"), [](FDescentStreamPoint& Out)
	{
		Out.LocationUU = Descent::MetresToUU(FVector(300.0, 50.0, -400.0));
		Out.RadiusM = 60.0;
		return true;
	});
	const FDescentHandle HA = F->RegisterFocus(TEXT("Carrier"), [](FDescentStreamPoint& Out)
	{
		Out.LocationUU = Descent::MetresToUU(FVector(0.0, 0.0, -30.0));
		Out.RadiusM = 120.0;
		return true;
	});
	TestTrue(TEXT("handles valid"), HA.IsValid() && HB.IsValid() && HA != HB);
	F->GetFocusPoints(Points);
	if (TestEqual(TEXT("two points"), Points.Num(), 2))
	{
		TestEqual(TEXT("first by owner name: Beacon"), Points[0].Owner, FName(TEXT("Beacon")));
		TestEqual(TEXT("second: Carrier"), Points[1].Owner, FName(TEXT("Carrier")));
		TestEqual(TEXT("radius carried"), Points[1].RadiusM, 120.0, 0.0);
		TestTrue(TEXT("location in Unreal units"), Points[1].LocationUU.Equals(FVector(0.0, 0.0, -3000.0)));
	}

	// A provider that has no point this time (the actor is gone) is skipped.
	bool bAlive = true;
	const FDescentHandle HT = F->RegisterFocus(TEXT("Tender"), [&bAlive](FDescentStreamPoint& Out)
	{
		Out.LocationUU = FVector(1.0, 2.0, 3.0);
		return bAlive;
	});
	F->GetFocusPoints(Points);
	TestEqual(TEXT("three points while the Tender is alive"), Points.Num(), 3);
	bAlive = false;
	F->GetFocusPoints(Points);
	TestEqual(TEXT("two once it has no point"), Points.Num(), 2);

	// Unregister.
	TestTrue(TEXT("unregister"), F->UnregisterFocus(HB));
	TestFalse(TEXT("unregister twice"), F->UnregisterFocus(HB));
	F->UnregisterFocus(HT);
	F->GetFocusPoints(Points);
	TestEqual(TEXT("only the carrier is left"), Points.Num(), 1);
	F->SetUseViewLocation(false);
	TestFalse(TEXT("view location switched off"), F->GetUseViewLocation());
	F->UnregisterFocus(HA);
	F->GetFocusPoints(Points);
	TestEqual(TEXT("nothing left"), Points.Num(), 0);

	AddExpectedError(TEXT("has an empty function"), EAutomationExpectedErrorFlags::Contains, 1);
	TestFalse(TEXT("an empty provider is refused"), F->RegisterFocus(TEXT("Empty"), UDescentStreamFocusSubsystem::FFocusFn()).IsValid());
	return true;
}

#endif // WITH_DEV_AUTOMATION_TESTS