Date Formatter code challenge

src/date_formatter.php

@@ -0,0 +1,43 @@
+<?php
+
+function date_formatter($date_string) {
+
+  // make sure passed argument is a string
+  if (gettype($date_string) !== 'string') {
+    return '';
+  }
+
+  // split string into year, month, date components
+  $date_parse_arr = explode('-', $date_string);
+
+  // checks to make sure that exactly 3 parts split by dashes were passed 
+  if (count($date_parse_arr) !== 3) {
+    return '';
+  }
+
+  // assign friendly variable names
+  $year = $date_parse_arr[0];
+  $month = $date_parse_arr[1];
+  $day = $date_parse_arr[2];
+
+  // make sure all components are numeric values
+  if (is_numeric($year) && is_numeric($month) && is_numeric($day)) {
+
+    // make sure components build into a valid date
+    if (checkdate((int)$month, (int)$day, (int)$year)) {
+      // combine into unix timestamp for date() function
+      $timestamp = mktime(0, 0, 0, $month, $day, $year);
+      $format = 'l, F jS Y';
+
+      return date($format, $timestamp);
+
+    } else {
+      return '';
+    }
+  } else {
+    return '';
+  }
+
+}
+
+?>