// ============= Test Cases =============
import type { Equal, Expect, NotEqual } from './test-utils'

type A1 = Flip<{ pi: 'a' }>;
type B1 = { a: 'pi' };
type C1 = Expect<Equal<A1, B1>>;

type A2 = Flip<{ pi: 3.14; bool: true }>;
type B2 = { 3.14: 'pi'; true: 'bool' };
type C2 = Expect<Equal<A2, B2>>;

type A3 = Flip<{ prop: 'val'; prop2: 'val2' }>;
type B3 = { val2: 'prop2'; val: 'prop' };
type C3 = Expect<Equal<A3, B3>>;

type A4 = Flip<{ pi: 'a' }>;
type B4 = { b: 'pi' };
type C4 = Expect<NotEqual<A4, B4>>

// ============= Your Code Here =============
type Flip<
  T extends Record<PropertyKey, string | number | boolean>
> = {
  [P in keyof T as `${T[P]}`]: P;
};

// ============== Alternatives ==============
// not the best.. Record<any, any>
type Flip<T extends Record<any, any>> = {
  [key in keyof T as `${T[key]}`]: key;
};

// a little better using PropertyKey
type Flip<T extends Record<PropertyKey, any>> = {
  [P in keyof T as
    T[P] extends PropertyKey
    ? T[P]
    : `${T[P]}`
  ]: P
};