Fish codility excercise

Trying to solve this challenge on codility fish challenge I cannot understand why not all the tests are passed by my code.

function solution($A, $B) {
  // write your code in PHP7.0
  $stack =[];

  foreach($A as $key =>$value) {
    if(empty($stack)){
      array_push($stack,$key);
    }
    else if($B[count($stack)-1] == 1 && $B[$key]==0 )
    {
      if($value > $A[count($stack)-1])
      {
        array_pop($stack);
        array_push($stack,$key);
      }
    }
    else array_push($stack,$key);
  }
  return count($stack);
}

Swift solution 100%:

public func solution(_ A : inout [Int], _ B : inout [Int]) -> Int {
    var stack = [(size: Int, direction: Int)]()
outer:
    for i in 0..<A.count {
        let currentFish = (size: A[i], direction: B[i])

        guard !stack.isEmpty, currentFish.direction == 0, stack.last?.direction == 1 else {
            stack.append(currentFish)
            continue
        }

        while stack.last?.direction == 1 {
            if stack.last!.size > currentFish.size {
                continue outer
            } else {
                stack.popLast()
            }
        }
        stack.append(currentFish)
    }
    return stack.count
}