IF formula help..little bit complicated

Hi All,

I need some help with a formula possibly with a string of IF statemants, i have been trying all morning but cant quite get it right.

I have attached the file that im working on.

Basically i have the RAG column (Column I, L, O, R) that i want to display either RED, AMBER or GREEN (or the letters R, A, G and then i can colour them using conditional formatting) depending on the following

Green = The required quantity (column G) is MORE than the stock (column F) & the promise date (Column H) is before the PIP date (H2) & the STATUS (Column E) is A or B

Amber = The required quantity (column G) is LESS than the stock (column F) but the promise date (Column H) is before the PIP date (H2) & the STATUS (Column E) is A or B

Red = The required quantity (column G) is LESS than the stock & the promise date (Column H) is NOT before the PIP date (H2) & the STATUS (Column E) is C or D or E

I then need the next RAG column (column L) to take into account its quanity requirments (column J) and the previous quantity requirments (column G) with regards to if there is enough stock or not and i will follow this through each time i add a new bar (AAA, BBB, CCC, DDD etc etc)

Much appreciated