Combining multiple if(functions in one cell

[fishdude]

Hi! 

So this one is a bit tricky. I'm trying to connect these three separate formulas into one cell: 
I got one formula which is - if this cell is salmon , and there is 1+ of them, choose this cell with input length cm to calculate weight, if not pick the cell with height (n12) and use this formula.

=IF(I12="salmon",IF(M12>0,SUM((((M12/100)^3)*10)*0.9711),SUM(0.004*N12^2.535))) - Works

then I got the same one for trout but without the height formula
=IF(I12="trout",IF(M12>0,SUM((((M12/100)^3)*10)*0.105) - Works

Now Im having trouble combining them; (last attempt)

IF(I11="trout",IF(M11>0,SUM((((M11/100^3)*10)*1.049)),IF(I11="salmon",IF(M11>0,SUM((((M11/100)^3)*10)*0.9711),SUM(0.004*N11^2.535)))))

Anyone got tips?

[#2]

@fishdude 

The logic In short: 
IF A(salmon) and B(1), and either C(length) or D(height); use E formula*C if C present or F formula* D if D present. But if A(trout) and B(1), and C (length) use G formula*C

[#3]

@fishdude 

As variant

=IF(I12="trout",
   IF(M12>0,
     ((M12/100)^3)*10*0.105,
     0
   ),
 IF(I12="salmon",
   IF(M12>0,
     ((M12/100)^3)*10*0.9711,
      0.004*N12^2.535
   ),
 0))