add controllers, servoices

app/Services/Semesters/SemesterConfigService.php

@@ -0,0 +1,41 @@
+<?php
+
+namespace App\Services\Semesters;
+
+use App\Models\Configuration;
+use DateTimeImmutable;
+
+class SemesterConfigService
+{
+    public function getFallStart(): ?DateTimeImmutable
+    {
+        return $this->parseDate(Configuration::getConfigValueByKey('fall_semester_start'));
+    }
+
+    public function getSpringStart(): ?DateTimeImmutable
+    {
+        return $this->parseDate(Configuration::getConfigValueByKey('spring_semester_start'));
+    }
+
+    public function getLastSchoolDay(): ?DateTimeImmutable
+    {
+        $value = Configuration::getConfigValueByKey('last_school_day')
+            ?? Configuration::getConfigValueByKey('last_day_of_school');
+
+        return $this->parseDate($value);
+    }
+
+    private function parseDate(?string $value): ?DateTimeImmutable
+    {
+        $value = (string) ($value ?? '');
+        if ($value === '') {
+            return null;
+        }
+
+        try {
+            return new DateTimeImmutable($value);
+        } catch (\Throwable) {
+            return null;
+        }
+    }
+}