<?php

namespace App\Console\Commands;

use App\Models\Device;
use App\Models\Entity;
use App\Services\NotificationService;
use Illuminate\Console\Command;
use Illuminate\Support\Facades\Cache;

/**
 * Sweeps for alert conditions (device offline, low battery) and e-mails the SMTP add-on when a NEW
 * one appears. A per-condition cache flag dedups, so you get one mail when it happens — not one
 * every sweep — and the flag clears once the condition resolves (with hysteresis for batteries).
 */
class NotificationsSweepCommand extends Command
{
    protected $signature = 'notifications:sweep';

    protected $description = 'E-mail on new alert conditions (device offline, low battery).';

    public function handle(NotificationService $notifier): int
    {
        // Nothing to do unless SMTP is configured.
        if ($notifier->config() === null) {
            return self::SUCCESS;
        }

        $this->sweepOffline($notifier);
        $this->sweepBatteries($notifier);

        return self::SUCCESS;
    }

    private function sweepOffline(NotificationService $notifier): void
    {
        foreach (Device::where('status', 'active')->where('demo', false)->get() as $device) {
            $key = "notified:offline:{$device->id}";

            if (! $device->isOnline()) {
                if (! Cache::has($key) && $notifier->notify('device_offline',
                    __('notifications.device_offline_subject', ['name' => $device->name]),
                    __('notifications.device_offline_body', ['name' => $device->name]))) {
                    // Flag stays until the condition RESOLVES (cleared below) — one mail per
                    // continuous outage, not one every 24h. The long TTL is just a leak guard.
                    Cache::put($key, true, now()->addMonth());
                }
            } else {
                Cache::forget($key);
            }
        }
    }

    private function sweepBatteries(NotificationService $notifier): void
    {
        $batteries = Entity::where('type', 'battery')->with('device', 'state')->get();

        foreach ($batteries as $entity) {
            if ($entity->device === null || $entity->device->demo) {
                continue;
            }

            // Missing reading defaults to 100 (no alert); a genuine 0% is a dead battery and MUST
            // alert — so the threshold is simply < 20 (a real 0 included).
            $pct = (int) data_get($entity->state, 'state.percent', 100);
            $key = "notified:battery:{$entity->id}";

            if ($pct < 20) {
                if (! Cache::has($key) && $notifier->notify('low_battery',
                    __('notifications.low_battery_subject', ['name' => $entity->device->name]),
                    __('notifications.low_battery_body', ['name' => $entity->device->name, 'percent' => $pct]))) {
                    Cache::put($key, true, now()->addMonth());
                }
            } elseif ($pct >= 25) {
                Cache::forget($key); // hysteresis so it doesn't flap around the threshold
            }
        }
    }
}