// Fill out your copyright notice in the Description page of Project Settings.


#include "WaveSubsystem.h"

void UWaveSubsystem::Init(TArray<UWave*> InWaves, int32 CurrWave = 0)
{
	CurrentWave = CurrWave;
	Waves = InWaves;
}

int32 UWaveSubsystem::SpawnWave(float InVerticalSpacing, float InHorizontalOffset, int InNumRows)
{
	NumRows = InNumRows;
	HorizontalOffset = InHorizontalOffset;
	VerticalSpacing = InVerticalSpacing;
	SpawnQueue = Waves[CurrentWave]->GetUnits();
	const auto NumUnits = SpawnQueue.Num(); 
	
	SpawnUnits();
	GetWorld()->GetTimerManager().SetTimer(
		SpawnTimerHandle,
		this,
		&UWaveSubsystem::SpawnUnits,
		0.5f,
		true);

	CurrentWave++;
	return NumUnits;
}

void UWaveSubsystem::SpawnUnits()
{
	for(auto i = 0; i < NumRows; i++)
	{
		if(i + LastSpawnIndex >= SpawnQueue.Num())
		{
			GetWorld()->GetTimerManager().ClearTimer(SpawnTimerHandle);
			return;
		}
		
		FVector Location = FVector(VerticalSpacing * i - VerticalSpacing, HorizontalOffset, 0);
		AActor* NewEnemy = GetWorld()->SpawnActor(SpawnQueue[i + LastSpawnIndex]->GetCharacterClass(), &Location);
		if(NewEnemy != nullptr)
		{
			NewEnemy->Tags.Add(TEXT("enemy"));
		}
	}

	LastSpawnIndex += NumRows;
}