How to get Last sunday date in Bootstrap Datepicker? - php

Question

I am using bootstrap Datepicker and I want to set the date for current/last Sunday.The code below is showing the content form $date to $date1.
if (!isset($_POST['new-date'])){
$date = date('Y-m-d H:i:s');// I want to set last/current sunday
date here.
$date1 = date("Y-m-d H:i:s", strtotime("$date +6 day"));
$d = explode(" ",$date);
$d1 = explode(" ",$date1);
} else {
$d[0] = $_POST['new-date'];
$d1[0] = date("Y-m-d", strtotime("$d[0] +6 day"));
}
$d[0] = $_POST['new-date'];
The ['new-date'] may be any day/date from the calendar but It should select the last Sunday of that particular week.

Answer 1

Your code seems to be written in PHP, rather than JavaScript, so I'm not sure how relevant the question title or tags are.
// Check if the day of the week is a Sunday. If yes, use today's date. If no, use last Sunday's date
$timestamp = date('N') == 7 ? strtotime('today') : strtotime('last sunday');
$date = date('Y-m-d H:i:s', $timestamp);
die($date);
Edit
You asked in the comments how you can find last Sunday for any given date.
$timestamp = strtotime($_POST['date'] ?? 'today');
$sunday = (date('N', $timestamp) == 7) ? $timestamp : strtotime('last sunday', $timestamp);
$date = date('Y-m-d H:i:s', $sunday);
die($date);