import nimpy # required version must be greater than "0.1.0"
from algorithm import sort

let op = pyImport("operator")
let pyuca = pyImport("pyuca") # pip install pyuca
let pyucaCollator = pyuca.Collator()
let icu = pyImport("icu") # pip install pyicu
let icuCollator = icu.Collator.createInstance() # for Locale support: icu.Collator.createInstance(icu.Locale("de"))

template cmpPython(a, b): int =
  op.sub(op.gt(a, b), op.gt(b, a)).to(int)

proc cmpUcaPyicu*(a, b: string): int =
  ## very good performance, harder to install
  let keyA = icuCollator.getSortKey(a)
  let keyB = icuCollator.getSortKey(b)
  return cmpPython(keyA, keyB)

proc cmpUcaPyuca*(a, b: string): int =
  ## bad performance, easy to install
  let keyA = pyucaCollator.sort_key(a)
  let keyb = pyucaCollator.sort_key(b)
  return cmpPython(keyA, keyB)

when isMainModule:
  var s = @[
    "cafe", "caff", "café"
  ]
  s.sort(cmp=cmpUcaPyuca)
  assert s == @["cafe", "café", "caff"]