Collect from Google Calendar and Outlook empty range slots

The synchonization need is for Google calendar and Outlook calendar. You will provide a way for the user to click on the link to register on his account which will allow us to extract the information from his calendar. (UI) I would like to extract from the 8am to 8pm (Variable) every day the empty slots range btw appointments within the next 96h , in a CSV format with the time, the date, the year. I will give you access to cpanel. As an example, if I have appointments btw 11:30am- 12:00pm and 3:00pm and 4:00pm, then the code that you will build will send us the following empty slot ranges. Knowledge needed is PHP. Knowledge Java, Javascript, PHP This info will include, Date, the year, the time. The extraction will be for the next 4 days Start date: 8am, End date: 11:30am Start date: 12pm End date:3pm Start date 4pm End date:8pm have empty slots btw 11am and 1:15pm, then the system will send me the following time 11:30am, 12pm, 12:30pm only. We will receive every day (Variable) an update of empty slot range if the calendar of the user is changing The system will let me send appointments (appointment A) with the necessary information to Google calendar or Outlook. If another appointment (appointment B) is scheduled by the user it self as the same time then the system will send me the information. We need to push appointments from our system to the calendar of the user. The user will click on a link that will let us push appointments with some information (Date, duration of the appointment, Year, Subject, Additional information).