feat(event): add per-user date change notices

app/Domains/Event/Services/EventDateNoticeService.php

@@ -0,0 +1,60 @@
+<?php
+
+namespace App\Domains\Event\Services;
+
+use App\Domains\Auth\Models\User;
+use App\Domains\Event\Models\EventDateChange;
+use App\Domains\Event\Models\EventDateChangeView;
+use App\Domains\Tenant\Models\Tenant;
+use Illuminate\Support\Facades\DB;
+
+class EventDateNoticeService
+{
+    public const MAX_DISPLAYS = 3;
+
+    public function __construct(private readonly EventDateNoticeFormatter $formatter) {}
+
+    /**
+     * Claims one display of every pending change and returns them grouped by type.
+     *
+     * @return list<array{
+     *     type: string,
+     *     change_ids: list<int>,
+     *     title: string,
+     *     message: list<array{text: string, bold: bool}>
+     * }>
+     */
+    public function claimFor(User $user, Tenant $tenant): array
+    {
+        return DB::transaction(function () use ($user, $tenant): array {
+            $lockedUser = User::query()->whereKey($user->getKey())->lockForUpdate()->firstOrFail();
+
+            $changes = EventDateChange::query()
+                ->where('tenant_code', $tenant->codigo)
+                ->whereDoesntHave('views', fn ($query) => $query
+                    ->where('user_id', $lockedUser->getKey())
+                    ->where('display_count', '>=', self::MAX_DISPLAYS))
+                ->orderBy('created_at')
+                ->orderBy('id')
+                ->get();
+
+            $notices = $this->formatter->format($changes);
+            $claimedChangeIds = collect($notices)->pluck('change_ids')->flatten()->unique();
+
+            foreach ($claimedChangeIds as $changeId) {
+                $view = EventDateChangeView::query()->firstOrNew([
+                    'user_id' => $lockedUser->getKey(),
+                    'event_date_change_id' => $changeId,
+                ]);
+                $view->display_count = min(
+                    self::MAX_DISPLAYS,
+                    ((int) $view->display_count) + 1,
+                );
+                $view->last_displayed_at = now();
+                $view->save();
+            }
+
+            return $notices;
+        });
+    }
+}