php失败场景，用于计算给定日期和持续时间的开始/结束日期

Question

I am working on a project management application for my client. The requirement was to create a task & assign to a given employee. I need to calculate start date if end date is given & viceversa. I hope that I have explained my code clearly with the comments.

The issue is that the response I get is incorrect only sometimes. I could not find the scenario in which it gives wrong date. Can you check my code & let me know if you can find the scenario in which it gives wrong date please so that I can fix.

I am given with restricted access to the server as this code is being executed through a despatcher & I do not have access to the log files.

Please help me solve the issue. Your help is much appreciated.

/**
    *** PARAMETERS ***
    * $givenDate - Carbon object
    * $totalDays - no. of days required/assigned for the task
    * $direction - calculate the date either forward or backward from the given date

    *** VARIABLES ***
    * $taskdays
        -> Array of dates in which tasks already assigned to the particular employee
    * $leaves
        -> Array of dates in which tasks the particular employee has applied for leave & approved
    * $holidays
        -> Array of dates - planned holidays for a particular branch of a company
        -> Since branches of the company are located in different countries, applicable holidays are also set based on the country of the branch location.
    * $weekends
        -> Array of days(eg., $days=array('Saturday', 'Sunday')) - weekends for a particular branch of a company.
        -> Since branches of the company are located in different countries, weekends are followed based on the country of the branch location.
        -> eg., Qatar(Friday & Saturday), India(Saturday & Sunday), Bangladesh(Sunday Only)
**/

private function calculateStartEndDates($givenDate, $totalDays=1, $direction='forward') {
    $taskdays = $this->getTaskAssignedDays($employeeId);
    $leaves = $this->getApprovedLeaveDays($employeeId);
    $holidays = $this->getHolidays($companyBranchId);
    $weekends = $this->getWeekends($companyBranchId);

    while($totalDays > 0) {
        if($direction == 'backward') {
            $givenDate = $givenDate->subDays(1);
        } else {
            $givenDate = $givenDate->addDays(1);
        }
        $currentDate = $givenDate->format('Y-m-d');
        if(!in_array($currentDate, $taskdays) && !in_array($currentDate, $leaves) && !in_array($currentDate, $holidays) && !in_array($givenDate->format('l'), $weekends)) {
            $totalDays--;
        }
    }
    return $givenDate;
}