feat: add two- and four-weekly series and drop the weekday picker

src/Booking/RecurrenceRule.php

@@ -4,16 +4,49 @@ declare(strict_types=1);
 
 namespace App\Booking;
 
+/**
+ * How often a series repeats.
+ *
+ * Every rule is a whole number of days, which is what lets BookingSeries::occurrences() be a
+ * plain stride from the start date. Every stride that is a multiple of 7 therefore keeps the
+ * weekday fixed by construction -- that is why a series needs no weekday field at all.
+ *
+ * There is deliberately no calendar-monthly rule: "the 31st of each month" has no counterpart in
+ * five months of the year, and it would not hold the weekday. FOUR_WEEKLY is the nearest thing
+ * that behaves, at the cost of drifting against the calendar -- 13 occurrences a year, not 12,
+ * which is why it is not labelled "Monatlich".
+ */
 enum RecurrenceRule: string
 {
     case DAILY = 'daily';
     case WEEKLY = 'weekly';
+    case TWO_WEEKLY = 'two_weekly';
+    case FOUR_WEEKLY = 'four_weekly';
 
     public function label(): string
     {
         return match ($this) {
             self::DAILY => 'Täglich',
             self::WEEKLY => 'Wöchentlich',
+            self::TWO_WEEKLY => 'Alle zwei Wochen',
+            self::FOUR_WEEKLY => 'Alle vier Wochen',
         };
     }
+
+    /** Days between two occurrences. */
+    public function intervalDays(): int
+    {
+        return match ($this) {
+            self::DAILY => 1,
+            self::WEEKLY => 7,
+            self::TWO_WEEKLY => 14,
+            self::FOUR_WEEKLY => 28,
+        };
+    }
+
+    /** Whether the rule lands on the same weekday every time, i.e. whether naming it adds anything. */
+    public function keepsWeekday(): bool
+    {
+        return 0 === $this->intervalDays() % 7;
+    }
 }

src/Controller/BookingController.php

@@ -132,7 +132,7 @@ final class BookingController extends AbstractController
         ]);
         // The day and any recurrence belong to the original booking; only the span is editable
         // here, so a series is never silently rewritten by editing one of its occurrences.
-        $form->remove('date')->remove('repeat')->remove('weekdays')->remove('until');
+        $form->remove('date')->remove('repeat')->remove('until');
         $form->handleRequest($request);
 
         if ($form->isSubmitted() && $form->isValid()) {
@@ -207,7 +207,6 @@ final class BookingController extends AbstractController
             $data->date,
             $data->until,
             $data->timeRange(),
-            $data->weekdays,
         ));
     }
 

src/Entity/BookingSeries.php

@@ -41,15 +41,6 @@ class BookingSeries
     #[ORM\Column(enumType: RecurrenceRule::class)]
     private RecurrenceRule $rule;
 
-    /**
-     * ISO weekdays (1 = Monday) the series falls on. Empty for a DAILY rule, which means
-     * every calendar day.
-     *
-     * @var list<int>
-     */
-    #[ORM\Column]
-    private array $weekdays = [];
-
     #[ORM\Column(type: 'date_immutable')]
     private \DateTimeImmutable $startDate;
 
@@ -69,9 +60,6 @@ class BookingSeries
     #[ORM\OneToMany(targetEntity: Booking::class, mappedBy: 'series')]
     private Collection $bookings;
 
-    /**
-     * @param list<int> $weekdays
-     */
     public function __construct(
         User $user,
         Resource $resource,
@@ -79,7 +67,6 @@ class BookingSeries
         \DateTimeImmutable $startDate,
         \DateTimeImmutable $endDate,
         TimeRange $time,
-        array $weekdays = [],
     ) {
         $this->user = $user;
         $this->resource = $resource;
@@ -88,7 +75,6 @@ class BookingSeries
         $this->endDate = $endDate->setTime(0, 0);
         $this->startMinute = $time->startMinute;
         $this->endMinute = $time->endMinute;
-        $this->weekdays = RecurrenceRule::WEEKLY === $rule ? array_values(array_unique($weekdays)) : [];
         $this->createdAt = new \DateTimeImmutable();
         $this->bookings = new ArrayCollection();
     }
@@ -96,17 +82,18 @@ class BookingSeries
     /**
      * Every day this series falls on, in order.
      *
+     * A rule is only a step size, so this is a stride from the start date. For any rule whose
+     * interval is a multiple of a week that means every occurrence lands on the same weekday as
+     * the start -- the series never has to be told which weekday it runs on.
+     *
      * @return list<\DateTimeImmutable>
      */
     public function occurrences(): array
     {
         $dates = [];
+        $step = \sprintf('+%d days', $this->rule->intervalDays());
 
-        for ($day = $this->startDate; $day <= $this->endDate; $day = $day->modify('+1 day')) {
-            if (RecurrenceRule::WEEKLY === $this->rule && !\in_array((int) $day->format('N'), $this->weekdays, true)) {
-                continue;
-            }
-
+        for ($day = $this->startDate; $day <= $this->endDate; $day = $day->modify($step)) {
             $dates[] = $day;
         }
 
@@ -133,14 +120,6 @@ class BookingSeries
         return $this->rule;
     }
 
-    /**
-     * @return list<int>
-     */
-    public function getWeekdays(): array
-    {
-        return $this->weekdays;
-    }
-
     public function getStartDate(): \DateTimeImmutable
     {
         return $this->startDate;
@@ -178,12 +157,11 @@ class BookingSeries
     {
         $description = $this->rule->label();
 
-        if (RecurrenceRule::WEEKLY === $this->rule && [] !== $this->weekdays) {
+        // Naming the weekday only says something for a rule that actually holds it fixed; for a
+        // daily series it would just repeat the start date back at the reader.
+        if ($this->rule->keepsWeekday()) {
             $names = ['', 'Mo', 'Di', 'Mi', 'Do', 'Fr', 'Sa', 'So'];
-            // Sort the numbers, not the names -- alphabetical would read "Di, Do, Fr, Mi, Mo".
-            $weekdays = $this->weekdays;
-            sort($weekdays);
-            $description .= ' ('.implode(', ', array_map(static fn (int $day): string => $names[$day], $weekdays)).')';
+            $description .= ' ('.$names[(int) $this->startDate->format('N')].')';
         }
 
         return $description.', '.$this->getTimeRange();

src/Form/BookingRequest.php

@@ -28,9 +28,6 @@ final class BookingRequest
 
     public ?RecurrenceRule $repeat = null;
 
-    /** @var list<int> ISO weekdays, 1 = Monday */
-    public array $weekdays = [];
-
     public ?\DateTimeImmutable $until = null;
 
     public function __construct(?\DateTimeImmutable $date = null, ?TimeRange $time = null)
@@ -92,10 +89,6 @@ final class BookingRequest
             return;
         }
 
-        if (RecurrenceRule::WEEKLY === $this->repeat && [] === $this->weekdays) {
-            $context->buildViolation('Bitte mindestens einen Wochentag wählen.')->atPath('weekdays')->addViolation();
-        }
-
         if (null === $this->until) {
             $context->buildViolation('Bitte ein Enddatum für die Serie angeben.')->atPath('until')->addViolation();
 

src/Form/BookingType.php

@@ -7,7 +7,6 @@ namespace App\Form;
 use App\Booking\RecurrenceRule;
 use Symfony\Component\Form\AbstractType;
 use Symfony\Component\Form\Extension\Core\Type\CheckboxType;
-use Symfony\Component\Form\Extension\Core\Type\ChoiceType;
 use Symfony\Component\Form\Extension\Core\Type\DateType;
 use Symfony\Component\Form\Extension\Core\Type\EnumType;
 use Symfony\Component\Form\Extension\Core\Type\TimeType;
@@ -49,13 +48,6 @@ final class BookingType extends AbstractType
                 'placeholder' => 'Einmalig',
                 'choice_label' => static fn (RecurrenceRule $rule): string => $rule->label(),
             ])
-            ->add('weekdays', ChoiceType::class, [
-                'label' => 'Wochentage',
-                'choices' => ['Mo' => 1, 'Di' => 2, 'Mi' => 3, 'Do' => 4, 'Fr' => 5, 'Sa' => 6, 'So' => 7],
-                'multiple' => true,
-                'expanded' => true,
-                'required' => false,
-            ])
             ->add('until', DateType::class, [
                 'label' => 'Serie bis',
                 'widget' => 'single_text',