Breaking up elapsed time into time slots

[JariV]

Hi,

I'm working on a work time tracking solution. Currently the work time data consists of begin and end times (timestamps) and four breakdown fields, where the elapsed work time is distributed according to its time slot for calculating corresponding time bonuses (normal hrs 6-18, evening hrs 18-22, night hrs 22-06 and sunday hrs). These all are static fields (they come from a tracking device), which means that when the user wants to edit the length of a work shift (begin or end time), the breakdown values don't change automatically.

I've been trying to figure out calculation fields for these breakdown time slots, which would use the begin and end timestamps, and would change when either of these is changed, but I'm running out of ideas.

Additional challenge is that a single workshift can be anything between 4 hrs to 5 days (truck drivers).

Any pointers how to approach this would be greatly appreciated.

Jari V