#define OLC_PGE_APPLICATION
#define OLC_SOUNDWAVE
#define OLC_PGEX_TRANSFORMEDVIEW
#include "olcUTIL_Geometry2D.h"

#include "VirusAttack.h"

VirusAttack::VirusAttack()
{
	// Name your application
	sAppName = "olcCodeJam 2023 Entry";
}

bool VirusAttack::OnUserCreate(){
	game.Initialise(GetScreenSize());

	CONSTANT::VIRUS_IMG1.Load("assets/unit.png");
	CONSTANT::SELECTION_CIRCLE.Load("assets/selection_circle.png");

	TILE.Load("assets/tile.png",nullptr,false,false);

	units.push_back(std::make_unique<BasicUnit>(vf2d{32,32},CONSTANT::VIRUS_IMG1,true));
	for(int i=0;i<10;i++){
		if(rand()%2==0){
			units.push_back(std::make_unique<BasicUnit>(vf2d{float(rand()%ScreenWidth()),float(rand()%ScreenHeight())},CONSTANT::VIRUS_IMG1,true));
		} else {
			units.push_back(std::make_unique<BasicUnit2>(vf2d{float(rand()%ScreenWidth()),float(rand()%ScreenHeight())},CONSTANT::VIRUS_IMG1,false));
		}
	}
	return true;
}

void VirusAttack::HandleDraggingSelection(){
	if(GetMouse(0).bPressed){
		for(auto&u:units){
			u->Deselect();
		}
		if(startingDragPos==CONSTANT::UNSELECTED){
			startingDragPos=GetWorldMousePos();
		}
	}
	if(GetMouse(0).bReleased){
		vf2d endDragPos=GetWorldMousePos();
		if(endDragPos.x<startingDragPos.x){std::swap(startingDragPos.x,endDragPos.x);}
		if(endDragPos.y<startingDragPos.y){std::swap(startingDragPos.y,endDragPos.y);}
		geom2d::rect<float> selectionRegion(startingDragPos,endDragPos-startingDragPos);
		for(auto&u:units){
			if(u->IsFriendly()){
				if(geom2d::overlaps(selectionRegion,u->GetPos())){
					u->Select();
				}
			}
		}
		startingDragPos=CONSTANT::UNSELECTED;
	}
}

vf2d VirusAttack::GetWorldMousePos(){	
	return game.ScreenToWorld(GetMousePos());
}

void VirusAttack::DrawSelectionRectangle(){
	if(startingDragPos!=CONSTANT::UNSELECTED){
		game.FillRectDecal(startingDragPos,GetWorldMousePos()-startingDragPos,{255,255,0,128});
	}
}

void VirusAttack::HandleRightClickMove(){
	if (GetMouse(1).bPressed){
		bool selectedTarget=false;
		for(auto&u:units){
			if(!u->IsFriendly()){
				geom2d::rect<float> unitRegion(u->GetPos()-u->GetUnitSize()/2,u->GetUnitSize());
				if(geom2d::overlaps(unitRegion,GetWorldMousePos())){
					for(auto&u2:units){
						if(u2->IsFriendly()&&u2->IsSelected()){
							u2->SetTargetUnit(u);
						}
					}
					selectedTarget=true;
					break;
				}
			}
		}
		if(!selectedTarget){
			for(auto&u:units){
				if(u->IsFriendly()&&u->IsSelected()){
					u->SetTargetLocation(GetWorldMousePos());
				}
			}
		}
	}
}

void VirusAttack::CollisionChecking(std::shared_ptr<Unit>u,std::shared_ptr<Unit>u2){
	if(u!=u2&&geom2d::overlaps(geom2d::circle<float>(u->GetPos(),u->GetUnitSize().x/2),geom2d::circle<float>(u2->GetPos(),u2->GetUnitSize().x/2))){
		geom2d::line<float>collisionLine(u->GetPos(),u2->GetPos());
		float maxDist=u->GetUnitSize().x/2+u2->GetUnitSize().x/2;
		float dist=maxDist-collisionLine.length();
		vf2d dir=collisionLine.vector().norm();
		u->SetPos(u->GetPos()-dir*dist/2);
		u2->SetPos(u2->GetPos()+dir*dist/2);
	}
}

void VirusAttack::IdentifyClosestTarget(Unit*&closestUnit,float&closestDist,std::shared_ptr<Unit>u,std::shared_ptr<Unit>u2){
	if(u->IsFriendly()!=u2->IsFriendly()){
		geom2d::line<float>unitLine(u->GetPos(),u2->GetPos());
		if(unitLine.length()<closestDist){
			closestUnit=u2.get();
			closestDist=unitLine.length();
		}
	}
}

bool VirusAttack::OnUserUpdate(float fElapsedTime){
	HandleDraggingSelection();
	HandleRightClickMove();

	if(GetKey(A).bHeld){
		game.MoveWorldOffset({-256*fElapsedTime,0});
	}
	if(GetKey(W).bHeld){
		game.MoveWorldOffset({0,-256*fElapsedTime});
	}
	if(GetKey(S).bHeld){
		game.MoveWorldOffset({0,256*fElapsedTime});
	}
	if(GetKey(D).bHeld){
		game.MoveWorldOffset({256*fElapsedTime,0});
	}

	if(GetMouseWheel()>0){
		if(game.GetWorldScale().x<2){
			game.ZoomAtScreenPos(1.25,GetMousePos());
		}
	} else
	if(GetMouseWheel()<0){
		if(game.GetWorldScale().x>0.5){
			game.ZoomAtScreenPos(0.75,GetMousePos());
		}
	}

	for(auto&u:units){
		Unit*closestUnit=nullptr;
		float closestDist=999999;
		for(auto&u2:units){
			IdentifyClosestTarget(closestUnit,closestDist,u,u2);
			CollisionChecking(u,u2);
		}
		u->AttemptAttack(closestUnit);
		u->Update(fElapsedTime);
	}
	game.DrawPartialDecal({0,0},CONSTANT::WORLD_SIZE*CONSTANT::TILE_SIZE,TILE.Decal(),{0,0},CONSTANT::WORLD_SIZE*CONSTANT::TILE_SIZE,DARK_GREEN);

	for(auto&u:units){
		u->Draw(game);
	}
	for(auto&u:units){
		u->DrawHud(game);
	}

	DrawSelectionRectangle();

	return true;
}

int main()
{
	VirusAttack app;
	if (app.Construct(426, 320, 4, 4))
		app.Start();
	return 0;
}