Adjust month view to year view.

functions/functions.php

@@ -22,6 +22,17 @@ function build_date_dropdown(mysqli $db, string $table): array
     return $dates;
 }
 
+function get_month(mysqli $db, string $table): array
+{
+    $date_query = 'SELECT MIN(date) AS first, MAX(date) AS last FROM ' . $table . ';';
+    $date = $db->query($date_query)->fetch_assoc();
+
+    $first_date = new DateTime($date['first']);
+    $last_date = new DateTime($date['last']);
+
+    return ['first' => $first_date, 'last' => $last_date];
+}
+
 function get_years(mysqli $db, string $table): array
 {
     $years_query = 'SELECT MIN(YEAR(date)) AS first, MAX(YEAR(date)) AS last FROM ' . $table . ';';