How to detect if HTML page is open on browser mobile or browser mobile mode in desktop?

I have done this code and work well in ios mobile browser, but not work in desktop ios mobile browser mode (Toggle Device Toolbar in browser).

var isSafari = /^((?!chrome|android|crios|fxios).)*safari/i.test(navigator.userAgent);

What I want is to validate if :

1. iOS with Safari = true
2. iOS in Desktop browser mode = false (I mean when we use Toggle Device Toolbar in the desktop browser)