<?php

namespace App\Temporal\SystemMonitor;

use App\Models\ImportJob;
use App\Models\Order;
use App\Models\OrderItem;
use App\Models\Product;
use App\Models\User;
use App\Temporal\Shared\FaultSimulator;
use Illuminate\Support\Facades\DB;
use Temporal\Activity;

class SystemMonitorActivity implements SystemMonitorActivityInterface
{
    public function runHealthCheck(array $simulationConfig = []): array
    {
        FaultSimulator::maybeApply($simulationConfig, 'runHealthCheck');

        $checks = [];
        $issues = 0;

        // 1. DB connectivity
        try {
            DB::select('SELECT 1');
            $checks['db_connected'] = true;
        } catch (\Throwable) {
            $checks['db_connected'] = false;
            $issues += 3; // critical
        }

        Activity::heartbeat(['step' => 'db_connectivity']);

        // 2. Table row counts
        $checks['product_count'] = Product::count();
        $checks['order_count'] = Order::count();
        $checks['order_item_count'] = OrderItem::count();
        $checks['user_count'] = User::count();
        $checks['import_job_count'] = ImportJob::count();

        Activity::heartbeat(['step' => 'row_counts']);

        // 3. Stale data check — pending orders older than 24h
        $checks['pending_stale_orders'] = Order::where('status', 'pending')
            ->where('created_at', '<', now()->subHours(24))
            ->count();
        if ($checks['pending_stale_orders'] > 0) {
            $issues++;
        }

        Activity::heartbeat(['step' => 'stale_data']);

        // 4. Stock alerts — active products with zero stock
        $checks['out_of_stock_products'] = Product::where('stock_quantity', 0)
            ->where('status', 'active')
            ->count();
        if ($checks['out_of_stock_products'] > 5) {
            $issues++;
        }

        Activity::heartbeat(['step' => 'stock_alerts']);

        // 5. Stuck import jobs — started but not updated in 30 min
        $checks['stuck_import_jobs'] = ImportJob::where('status', 'started')
            ->where('updated_at', '<', now()->subMinutes(30))
            ->count();
        if ($checks['stuck_import_jobs'] > 0) {
            $issues++;
        }

        Activity::heartbeat(['step' => 'stuck_jobs']);

        // Compute health score (100 = perfect, deduct per issue)
        $healthScore = max(0, 100 - ($issues * 10));

        return [
            'timestamp' => now()->toISOString(),
            'checks' => $checks,
            'healthScore' => $healthScore,
            'issues' => $issues,
            'attempt' => Activity::getInfo()->attempt,
        ];
    }
}