enum Comparison {
  Greater,
  Equal,
  Lower,
}

type Negate<C extends Comparison> =
  C extends Comparison.Greater
  ? Comparison.Lower
  : C extends Comparison.Lower
  ? Comparison.Greater
  : Comparison.Equal

type CompareDigit<A extends string | number, B extends string | number> =
  `${A}` extends `${B}` ? Comparison.Equal
  : `0123456789` extends `${string}${A}${string}${B}${string}`
  ? Comparison.Lower
  : Comparison.Greater

type ComparePositives<A extends string | number, B extends string | number> =
  `${A}` extends `${infer A1}${infer RA}`
    ? `${B}` extends `${infer B1}${infer RB}`
      ? CompareDigit<A1, B1> extends Comparison.Equal
        ? ComparePositives<RA, RB>
      : CompareDigit<A1, B1>
    : Comparison.Greater
  : `${B}` extends `${infer _}${infer _}`
    ? Comparison.Lower
  : Comparison.Equal

type ComparatorHelper<A extends string | number, B extends string | number, IsNegative extends boolean = false> =
  IsNegative extends true
  ? Negate<ComparePositives<A, B>>
  : ComparePositives<A, B>

type Comparator<A extends number, B extends number> =
  `${A}` extends `-${infer Aabs}`
    ? `${B}` extends `-${infer Babs}`
      ? ComparatorHelper<Aabs, Babs, true>
    : Comparison.Lower
  : `${B}` extends `-${number}`
    ? Comparison.Greater
  : ComparatorHelper<A, B>

import type { Equal, Expect } from '@type-challenges/utils'

type cases = [
  Expect<Equal<Comparator<5, 5>, Comparison.Equal>>,
  Expect<Equal<Comparator<5, 6>, Comparison.Lower>>,
  Expect<Equal<Comparator<5, 8>, Comparison.Lower>>,
  Expect<Equal<Comparator<5, 0>, Comparison.Greater>>,
  Expect<Equal<Comparator<-5, 0>, Comparison.Lower>>,
  Expect<Equal<Comparator<0, 0>, Comparison.Equal>>,
  Expect<Equal<Comparator<0, -5>, Comparison.Greater>>,
  Expect<Equal<Comparator<5, -3>, Comparison.Greater>>,
  Expect<Equal<Comparator<5, -7>, Comparison.Greater>>,
  Expect<Equal<Comparator<-5, -7>, Comparison.Greater>>,
  Expect<Equal<Comparator<-5, -3>, Comparison.Lower>>,
  Expect<Equal<Comparator<-25, -30>, Comparison.Greater>>,
  Expect<Equal<Comparator<15, -23>, Comparison.Greater>>,
  Expect<Equal<Comparator<40, 37>, Comparison.Greater>>,
  Expect<Equal<Comparator<-36, 36>, Comparison.Lower>>,
  Expect<Equal<Comparator<27, 27>, Comparison.Equal>>,
  Expect<Equal<Comparator<-38, -38>, Comparison.Equal>>,
]