const ALIEN_SPEED = 130;       // pixels/sec
const ALIEN_FIRE_RATE = 2500;  // ms between shots

export default class AlienShip {
    constructor(scene, x, y, group) {
        this.scene = scene;
        this.alive = true;

        this.sprite = scene.physics.add.sprite(x, y, 'alien');
        group.add(this.sprite);
        this.sprite.gameEntity = this;
        this.sprite.body.setAllowGravity(false);

        // Circular hitbox: texture is 64x48, use radius 20 centered at (32,24)
        this.sprite.body.setCircle(20, 12, 4);

        this.lastFired = 0;
    }

    update(time, player) {
        if (!this.alive) return;
        if (!player || !player.alive || !player.sprite.active) return;

        // Move toward player
        const dx = player.sprite.x - this.sprite.x;
        const dy = player.sprite.y - this.sprite.y;
        const dist = Math.sqrt(dx * dx + dy * dy);

        if (dist > 5) {
            this.sprite.setVelocity(
                (dx / dist) * ALIEN_SPEED,
                (dy / dist) * ALIEN_SPEED
            );
        }

        // Fire at player periodically
        if (time - this.lastFired > ALIEN_FIRE_RATE) {
            this.lastFired = time;
            const angle = Phaser.Math.RadToDeg(Math.atan2(dy, dx));
            this.scene.spawnAlienBullet(this.sprite.x, this.sprite.y, angle);
        }

        // Wrap around screen
        this.scene.physics.world.wrap(this.sprite, 40);
    }

    destroy() {
        if (!this.alive) return;
        this.alive = false;
        if (this.sprite && this.sprite.active) {
            this.sprite.destroy();
        }
    }
}