Array summation conditioned on maximum and uniques

Question

Given three arrays, for example

s={1,3,2,3,1,2,3,2,1}
r={4,2,6,5,4,6,2,1,3}
f={1,3,9,1,8,4,4,8,2}

I'm trying to output four summary arrays

1. The uniques of s
2. For each unique of s, the maximum of r with that s
3. The number of entries which have that (s,r) combination
4. The sum of f's of those corresponding entries

For example

o1={1,2,3}
o2={4,6,5}
o3={2,2,1}
o4={9,13,1}

(For s=1 the maximum r values was 4, of which there were two of them, and the sum of the corresponding f values is 1+8=9)

I've been doing a loop across the uniques using Position function, etc. Slow and not optimized using the Mathematica notation. The arrays can be millions in length.

Thank you for your help.

Answer 1

{o1, o2, o3, o4} = Transpose @  Values @ KeySort @
  GroupBy[Transpose[{s, r, f}], First, 
     Apply[{First @ #, First @ #2, Length @ #2, Total @ #3} &] @* 
       Transpose @* MaximalBy[#[[2]] &]]

{{1, 2, 3}, {4, 6, 5}, {2, 2, 1}, {9, 13, 1}}