wip: refactor forms

src/Form/ParticipantFieldHandler/AbstractParticipantFieldHandler.php

@@ -0,0 +1,119 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Form\ParticipantFieldHandler;
+
+use App\Form\Model\BookingCreateDto;
+
+/**
+ * Abstract base class providing common functionality for participant field handlers.
+ *
+ * This class implements common patterns used across participant field handlers,
+ * reducing boilerplate code in concrete implementations.
+ */
+abstract class AbstractParticipantFieldHandler implements ParticipantFieldHandlerInterface
+{
+    /**
+     * Returns the field names this handler depends on.
+     *
+     * Default implementation returns an empty array, meaning no dependencies.
+     * Override this method in concrete handlers that depend on other fields
+     * being processed first (e.g., a meal preference handler might depend on
+     * the room assignment being processed first).
+     *
+     * @return string[] Array of field names that must be processed before this handler
+     */
+    public function getDependencies(): array
+    {
+        return [];
+    }
+
+    /**
+     * Determines if this handler should process the field based on submitted data.
+     *
+     * Default implementation checks if the field exists in the submitted data.
+     * Override this method for more complex processing conditions (e.g., only
+     * process if certain other conditions are met).
+     *
+     * @param array<string, mixed> $submittedData    The submitted participant form data
+     * @param int                  $participantIndex The index of the participant being processed
+     *
+     * @return bool True if the handler should process this field, false otherwise
+     */
+    public function shouldProcess(array $submittedData, int $participantIndex): bool
+    {
+        return isset($submittedData[$this->getFieldName()]);
+    }
+
+    /**
+     * Safely retrieves a participant object from the booking DTO.
+     *
+     * This helper method provides safe access to participant data by checking
+     * if the participant exists at the given index. Returns null if the
+     * participant doesn't exist, preventing array access errors.
+     *
+     * @param BookingCreateDto $bookingDto       The booking DTO containing participants
+     * @param int              $participantIndex The index of the participant to retrieve
+     *
+     * @return object|null The participant object, or null if not found
+     */
+    protected function getParticipant(BookingCreateDto $bookingDto, int $participantIndex): ?object
+    {
+        return $bookingDto->participants[$participantIndex] ?? null;
+    }
+
+    /**
+     * Safely extracts a field value from submitted participant data.
+     *
+     * This helper method provides safe access to form field values using
+     * the null coalescing operator. Useful for extracting field values
+     * without worrying about undefined array keys.
+     *
+     * @param array<string, mixed> $submittedData The submitted participant form data
+     * @param string               $fieldName     The name of the field to retrieve
+     * @param mixed                $default       The default value to return if field is not set
+     *
+     * @return mixed The field value, or the default value if not found
+     */
+    protected function getFieldValue(array $submittedData, string $fieldName, mixed $default = null): mixed
+    {
+        return $submittedData[$fieldName] ?? $default;
+    }
+
+    /**
+     * Normalizes empty string values to null.
+     *
+     * Form inputs often submit empty strings for unselected/empty fields.
+     * This helper converts those empty strings to null values, which is
+     * typically more appropriate for database storage and business logic.
+     *
+     * @param mixed $value The value to normalize
+     *
+     * @return mixed The normalized value (null if empty, original value otherwise)
+     */
+    protected function normalizeEmptyValue(mixed $value): mixed
+    {
+        return empty($value) ? null : $value;
+    }
+
+    /**
+     * Converts and normalizes string values to integers.
+     *
+     * Form inputs submit all values as strings. This helper safely converts
+     * string values to integers while handling empty strings and non-numeric
+     * values gracefully by returning null.
+     *
+     * @param mixed $value The value to convert to integer
+     *
+     * @return int|null The integer value, or null if empty/non-numeric
+     */
+    protected function normalizeIntValue(mixed $value): ?int
+    {
+        if (empty($value)) {
+            return null;
+        }
+
+        return is_numeric($value) ? (int) $value : null;
+    }
+}