Array of discounts to be applied based on the weeks booked all at different rate

[joesaddigh]

Array of discounts to be applied based on the weeks booked all at different rate

 

 

Hi,

 

Sorry about the title, it will hopefully become clearer when I explain my problem. OK the problem is as follows:

 

BACKGROUND INFORMATION

Admin - add a course and apply some discounts. There can be multiple discounts per course.

The format of a discount is:

(NAME-WEEKS-DISCOUNT)

NAME = The name of the discount - pointless mentioning

WEEKS = The discount will be applied for subsequent weeks after this value ( if WEEKS = 2 and user books for 3 then the DISCOUNT will be applied for weeks after this value ).

DISCOUNT = a decimal format for a discount rate which should be applied e.g. 10 OR 20 OR 50.6 etc NO MORE THAN 100 and more than 0.

 

The above is all implemented. I have a course calculator which will use this information quoted above:

For example: User picks a course and a duration ( 10 weeks )

 

When this is submitted I need to give them a price.

 

As the weeks booked is variable and the amount of discounts for the chosen course is variable I would like to know the best way of calculating this. I currently have some code to do this and it seems to work but without a debugger I can't truely check it is accurate ( I think it might be doing something suttely wrong and if not the code is messy and hard to understand)

 

Can anybody give me a good solution mathmatically which I can implement where by I can work out how much the total will be:

 

Scenario in pseudo sort of code:

 

$weeksbooked = 30

 

// Get the discounts from db

// There are 3 so store these in array?

// Example of array contents

// Discount rate - qualifier(after how many weeks) - course price

array[ 0 ] = 10%-5-£100

array[ 1 ] = 20%-10-£100

array[ 2 ] = 30%-15-£100

 

So I would need to do the following maths:

5 weeks at normal price £100

5 weeks at £100 - 10%

5 weeks at £100 - 20%

THE REMAINING weeks at £100 - 30%

 

( £500 + £450 + £400 ) + REMAINING WEEKS at 30% discount ( £1350 + 1050 )

£2400

 

Please any ideas would be greatly received: