/** Throws if 
 * @param number[]
 * @returns number[]
 */

function arrayPreviousLess(nums) {
  if(!Array.isArray(nums)){
      throw new Error("Invalid input");
  }
  const { length } = nums;
  const arrayClone = [...nums];
  outerLoop: for (let i = 0; i < length; i += 1) {
    if(typeof nums[i] !== 'number'){
        throw new Error('Invalid input');
    }
    for (let j = i - 1; j >= 0; j -= 1) {
      if (nums[i] > nums[j]) {
        arrayClone[i] = nums[j];
        continue outerLoop;
      }
    }
    arrayClone[i] = -1;
  }
  return arrayClone;
}

/* SOLUTION 2
 function arrayPreviousLess(nums) {
  if(!Array.isArray(nums)){
      throw new Error("Invalid input");
  }
  const arrayClone = [...nums];
  nums.forEach((element, index) => {
     if(typeof element !== 'number'){
        throw new Error('Invalid input');
     }
     for(let i = index - 1; i >= 0; i--){
       if(element > nums[i]){
          arrayClone[index] = nums[i];
          return;
       }
     }
     arrayClone[index] = -1;
  })
  return arrayClone;
}
 
 */
/**
* Test Suite 
*/
describe('arrayPreviousLess()', () => {
     it('expects arrayPreviousLess to be a function', () => {
        expect(typeof arrayPreviousLess === "function").toBe(true);
    });
    it('expects arrayPreviousLess([3, 5, 2, 4, 5]) to return [-1, 3, -1, 2, 4]', () => {
        expect(arrayPreviousLess([3, 5, 2, 4, 5])).toEqual([-1, 3, -1, 2, 4]);
    });
    it('expects arrayPreviousLess([]) to return []', () => {
        expect(arrayPreviousLess([])).toEqual([]);
    });
     it('expects arrayPreviousLess([2, 2, 2]) to return [-1, -1, -1]', () => {
        expect(arrayPreviousLess([2, 2, 2])).toEqual([-1, -1, -1]);
    });
     it('expects arrayPreviousLess([1, 2, 3, 10]) to return [-1, 1, 2, 3]', () => {
        expect(arrayPreviousLess([1, 2, 3, 10])).toEqual([-1, 1, 2, 3]);
    });
    it('expects arrayPreviousLess([5, 3, 2]) to return [-1, -1, -1]', () => {
        expect(arrayPreviousLess([5, 3, 2])).toEqual([-1, -1, -1]);
    });
     it('expects arrayPreviousLess([5, 3, "2"]) to throw an error', () => {
        expect(() => arrayPreviousLess([5, 3, '2'])).toThrow(new Error('Invalid input'));
    });
    it('expects arrayPreviousLess([0]) to return [-1]', () => {
        expect(arrayPreviousLess([0])).toEqual([-1]);
    });
    it('expects arrayPreviousLess(false) to throw an error', () => {
        expect(() => arrayPreviousLess(false)).toThrow(new Error('Invalid input'));
    });
    
});