given a circle and a point outside of circle get tangent point on circle edge in typescript

index.ts
interface Point {
  x: number;
  y: number;
}

interface Circle {
  center: Point;
  radius: number;
}

function getTangentPoint(circle: Circle, point: Point): Point[] {
  const dx = point.x - circle.center.x;
  const dy = point.y - circle.center.y;
  const distance = Math.sqrt(dx * dx + dy * dy);

  if (distance < circle.radius) {
    // Point is inside the circle, there is no tangent.
    return [];
  } else if (distance === circle.radius) {
    // Point is on the circle edge, there is a single tangent point.
    return [{ x: point.x, y: point.y }];
  } else {
    // Point is outside the circle, there are two tangent points.
    const angle = Math.atan2(dy, dx);
    const tangentAngle = Math.asin(circle.radius / distance);

    const tangentPoint1: Point = {
      x: circle.center.x + circle.radius * Math.cos(angle + tangentAngle),
      y: circle.center.y + circle.radius * Math.sin(angle + tangentAngle)
    };

    const tangentPoint2: Point = {
      x: circle.center.x + circle.radius * Math.cos(angle - tangentAngle),
      y: circle.center.y + circle.radius * Math.sin(angle - tangentAngle)
    };

    return [tangentPoint1, tangentPoint2];
  }
}

// Example usage:
const circle: Circle = {
  center: { x: 0, y: 0 },
  radius: 5
};

const point: Point = { x: 10, y: 0 };

const tangentPoints = getTangentPoint(circle, point);
console.log(tangentPoints);
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