<?php

declare(strict_types=1);

namespace App\Game;

abstract class GameObject
{
    private static int $nextId = 0;

    public readonly int $eid;

    public Vector2 $pos;

    public Vector2 $velocity;

    public float $width;

    public float $height;

    public function __construct(float $x = 0.0, float $y = 0.0)
    {
        $this->eid = ++self::$nextId;
        $this->pos = new Vector2($x, $y);
        $this->velocity = Vector2::zero();
        $this->width = 0.0;
        $this->height = 0.0;
    }

    public function update(float $dt): void
    {
        $this->move($dt);
    }

    /** Integrate position from velocity; used directly by subclasses that override update(). */
    public function move(float $dt): void
    {
        $this->pos = new Vector2(
            $this->pos->x + $this->velocity->x * $dt,
            $this->pos->y + $this->velocity->y * $dt,
        );
    }

    public function intersects(GameObject $other): bool
    {
        return abs($this->pos->x - $other->pos->x) * 2.0 < $this->width + $other->width
            && abs($this->pos->y - $other->pos->y) * 2.0 < $this->height + $other->height;
    }

    public function removeFrom(EntityList $container): void
    {
        $container->remove($this);
    }

    abstract public function kind(): string;
}