POC -Sending Calendar Invite from PHP application

I want to build a small PHP custom application POC with three text boxes and one button. One field will accept an email address, a second text box with a text area, and another will take date & time. Once I hit send, I wanted to send a calendar invite to the email address as ICS file so that it would show as a meeting invite in their calendar. Email can be Gmail/outlook or any email extension. Please host this on your server and show me a demo.