I need some help regarding the implementation of the following alarm.. Here's the flow of the program, user login to the system and then they can click the hyperlink create schedule and then from there they can create schedules using the form. After which, user can choose to start this schedules that they created and they can allocate a timeframe to it. For eg, if the user assign the schedule to run at 2pm the system will have a pop up to notify and inform the user to run this schedule probably 15 mins before 2pm..
I would like to know what are the ways to implement this in php and if possible is there any reference i can use on the website? I've tried to find but apparently most scripts are paid etc.