feat: state, window and quiet rules

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BCrwHHnGCB5XH968Nxokqw

core/app/Scheduling/WindowResolver.php

@@ -0,0 +1,55 @@
+<?php
+
+namespace App\Scheduling;
+
+use App\Enums\EventState;
+use App\Models\User;
+use Carbon\CarbonImmutable;
+
+final class WindowResolver
+{
+    /** @param list<int> $fallbackHours */
+    public function __construct(
+        private readonly int $dayMarginMinutes,
+        private readonly int $hourMarginMinutes,
+        private readonly array $fallbackHours,
+    ) {}
+
+    /** Окно, открытое в момент $now, или null (тихие часы / срок прошёл / состояние не напоминает). */
+    public function current(EventState $state, User $user, Due $due, CarbonImmutable $now): ?Window
+    {
+        $activeStart = $user->activeStart($now);
+        $activeEnd = $user->activeEnd($now);
+        if ($now->lt($activeStart) || $now->gte($activeEnd)) {
+            return null;
+        }
+
+        return match ($state) {
+            EventState::Preparing, EventState::Overdue => new Window(
+                $activeStart, $activeEnd, true, $activeEnd->subMinutes($this->dayMarginMinutes),
+            ),
+            EventState::Today => $this->hourly($due, $now, $activeEnd),
+            default => null,
+        };
+    }
+
+    private function hourly(Due $due, CarbonImmutable $now, CarbonImmutable $activeEnd): ?Window
+    {
+        $start = $now->startOfHour();
+        $end = $start->addHour()->min($activeEnd);
+
+        $truncated = false;
+        if ($due->moment->gt($start) && $due->moment->lt($end)) {
+            $end = $due->moment;
+            $truncated = true;
+        }
+
+        if ($now->gte($end)) {
+            return null;
+        }
+
+        $fallbackAllowed = $truncated || in_array((int) $start->format('G'), $this->fallbackHours, true);
+
+        return new Window($start, $end, $fallbackAllowed, $end->subMinutes($this->hourMarginMinutes));
+    }
+}