How to get camera.setVew parameter?

CesiumJS
1 
viewer.camera.setView( { 
    destination: Cesium.Cartesian3.fromDegrees(x, y, z),
    orientation: {
        heading: Cesium.Math.toRadians(h),
        pitch: Cesium.Math.toRadians(p), 
        roll: Cesium.Math.toRadians(r)
    } 
})

How to get current x y z h p r, so I can call setView method to reuse current scene view?