openquell/systems/obstacle_system.go

package systems

import (
	"log/slog"
	"openquell/assets"
	"openquell/components"
	. "openquell/components"
	. "openquell/config"
	"openquell/grid"
	"openquell/observers"
	"openquell/util"

	"github.com/hajimehoshi/ebiten/v2"
	"github.com/mlange-42/arche/ecs"
	"github.com/mlange-42/arche/generic"
)

type ObstacleSystem struct {
	World         *ecs.World
	Selector      *generic.Filter4[Position, Velocity, Obstacle, Renderable]
	GridContainer *grid.GridContainer
}

func NewObstacleSystem(world *ecs.World, gridcontainer *grid.GridContainer) System {
	system := &ObstacleSystem{
		Selector:      generic.NewFilter4[Position, Velocity, Obstacle, Renderable](),
		World:         world,
		GridContainer: gridcontainer,
	}

	return system
}

func (system *ObstacleSystem) Update() error {
	playerobserver := observers.GetPlayerObserver(system.World)
	gameobserver := observers.GetGameObserver(system.World)

	if gameobserver.Lost {
		return nil
	}

	var gameover bool

	if len(playerobserver.Entities) == 0 {
		// FIXME: check this in game or elsewhere
		gameover = true
	}

	if gameover {
		// winner, winner,  chicken dinner!
		timer := gameobserver.StopTimer

		if !timer.Running {
			timer.Start(LEVEL_END_WAIT)
		}

		gameobserver.Gameover()
	}

	return nil
}

func (system *ObstacleSystem) Draw(screen *ebiten.Image) {
	// write the movable tiles
	op := &ebiten.DrawImageOptions{}
	query := system.Selector.Query(system.World)

	for query.Next() {
		pos, _, _, sprite := query.Get()

		op.GeoM.Reset()
		op.GeoM.Translate(float64(pos.X), float64(pos.Y))

		screen.DrawImage(sprite.Image, op)
	}
}

func (system *ObstacleSystem) AddParticle(position *components.Position) {
	particleobserver := observers.GetParticleObserver(system.World)

	ptmapper := generic.NewMap3[
		components.Position,
		components.Particle,
		components.Timer,
	](system.World)

	entity := ptmapper.New()
	pos, particle, timer := ptmapper.Get(entity)
	particleobserver.AddEntity(entity)

	particle.Index = assets.Tiles['*'].Particle
	particle.Tiles = assets.Tiles['*'].Tiles

	pos.Update(
		position.X-(16), // FIXME: use global tilesize!
		position.Y-(16),
		64,
	)

	timer.Start(PARTICLE_LOOPWAIT)
}

// return true if obstacle weapon points into the direction the player is moving
func CheckObstacleSide(playervelocity *Velocity, obsdirection int) bool {
	movingdirection := playervelocity.InvertDirection()

	if movingdirection == Stop || movingdirection == obsdirection {
		slog.Debug("Damaging obstacle collision",
			"playerdirection", util.DirectionStr(playervelocity.Direction),
			"obsdirection", util.DirectionStr(obsdirection),
			"movingdirection", util.DirectionStr(movingdirection),
		)
		return true
	}

	return false
}