What patterns to apply when calculating payroll?

Question

PHP

There is a self-written system engine, it has several points where salaries are calculated based on telephony data. The result of the calculations is an HTML display, or a PDF document, or the resulting sum for other blocks of logic.
Tell me what patterns you can implement this logic in such a way that all calculations take place at one point in the code, and depending on the need, we get this result in HTML, or PDF, or just the resulting figure.
The counting logic is ambiguous, it's not just a selection from one table, but also mathematical calculations over the duration using other parameters, plus the selection takes place in several stages from different tables, which does not allow you to get a figure in the calculation and simply wrap it in HTML or PDF, it is also necessary to produce a listing of the selected lines.

Answer 1

The Builder pattern in its purest form.

Answer 2

For salary calculations with changing indicators, I would advise using the Decorator pattern .
It was created just for such purposes.