Matter JS Compound Sensors

class Example extends Phaser.Scene
{
    cursors;
    player;

    preload ()
    {
        this.load.setBaseURL('https://cdn.phaserfiles.com/v410');
        this.load.image('block', 'assets/sprites/block.png');
        this.load.image('platform', 'assets/sprites/platform.png');
    }

    create ()
    {
        const Bodies = Phaser.Physics.Matter.Matter.Bodies;

        const rect = Bodies.rectangle(0, 0, 98, 98);
        const circleA = Bodies.circle(-70, 0, 24, { isSensor: true, label: 'left' });
        const circleB = Bodies.circle(70, 0, 24, { isSensor: true, label: 'right' });
        const circleC = Bodies.circle(0, -70, 24, { isSensor: true, label: 'top' });
        const circleD = Bodies.circle(0, 70, 24, { isSensor: true, label: 'bottom' });

        const compoundBody = Phaser.Physics.Matter.Matter.Body.create({
            parts: [ rect, circleA, circleB, circleC, circleD ],
            inertia: Infinity
        });

        this.player = this.matter.add.image(0, 0, 'block');

        this.player.setExistingBody(compoundBody);
        this.player.setPosition(100, 300);

        const testA = this.matter.add.image(400, 150, 'block').setStatic(true);
        const testB = this.matter.add.image(600, 450, 'block').setStatic(true);
        const testC = this.matter.add.image(200, 550, 'block').setStatic(true);

        this.matter.world.on('collisionstart', event =>
        {

            //  Loop through all of the collision pairs
            const pairs = event.pairs;

            for (let i = 0; i < pairs.length; i++)
            {
                const bodyA = pairs[i].bodyA;
                const bodyB = pairs[i].bodyB;

                //  We only want sensor collisions
                if (pairs[i].isSensor)
                {
                    let blockBody;
                    let playerBody;

                    if (bodyA.isSensor)
                    {
                        blockBody = bodyB;
                        playerBody = bodyA;
                    }
                    else if (bodyB.isSensor)
                    {
                        blockBody = bodyA;
                        playerBody = bodyB;
                    }

                    //  You can get to the Sprite via `gameObject` property
                    const playerSprite = playerBody.gameObject;
                    const blockSprite = blockBody.gameObject;

                    let color;

                    if (playerBody.label === 'left')
                    {
                        color = 0xff0000;
                    }
                    else if (playerBody.label === 'right')
                    {
                        color = 0x00ff00;
                    }
                    else if (playerBody.label === 'top')
                    {
                        color = 0x0000ff;
                    }
                    else if (playerBody.label === 'bottom')
                    {
                        color = 0xffff00;
                    }

                    blockSprite.setTint(color).setTintMode(Phaser.TintModes.FILL);
                }
            }

        });

        this.cursors = this.input.keyboard.createCursorKeys();

        this.add.text(10, 10, 'Move with cursor keys. Hit blocks with sensors.', { font: '16px Courier', fill: '#ffffff' });
    }

    update ()
    {
        if (this.cursors.left.isDown)
        {
            this.player.setVelocityX(-10);
        }
        else if (this.cursors.right.isDown)
        {
            this.player.setVelocityX(10);
        }
        else
        {
            this.player.setVelocityX(0);
        }

        if (this.cursors.up.isDown)
        {
            this.player.setVelocityY(-10);
        }
        else if (this.cursors.down.isDown)
        {
            this.player.setVelocityY(10);
        }
        else
        {
            this.player.setVelocityY(0);
        }
    }
}

const config = {
    scale: { mode: Phaser.Scale.FIT },
    type: Phaser.AUTO,
    width: 800,
    height: 600,
    backgroundColor: '#1b1464',
    parent: 'game-container',
    physics: {
        default: 'matter',
        matter: {
            debug: true,
            gravity: {
                y: 0
            }
        }
    },
    scene: Example
};

const game = new Phaser.Game(config);