<?php

namespace App\Http\Controllers\Admin;

use App\Http\Controllers\Controller;
use App\Models\User;
use Illuminate\Support\Facades\DB;
use Inertia\Inertia;
use Spatie\Activitylog\Models\Activity;

class AdminController extends Controller
{
    public function index()
    {
        return Inertia::render('Admin/Index', [
            'stats' => [
                'users'    => User::count(),
                'sessions' => DB::table('sessions')->count(),
                'queued'   => DB::table('jobs')->count(),
                'db_size'  => $this->dbSize(),
            ],
            'recent_activity' => Activity::with('causer')
                ->orderByDesc('created_at')
                ->limit(10)
                ->get(),
        ]);
    }

    public function auditLog()
    {
        return Inertia::render('Admin/AuditLog', [
            'logs' => Activity::with('causer', 'subject')
                ->orderByDesc('created_at')
                ->paginate(50),
        ]);
    }

    public function systemHealth()
    {
        return Inertia::render('Admin/SystemHealth', [
            'health' => [
                'database' => $this->checkDatabase(),
                'cache'    => $this->checkCache(),
                'queue'    => $this->checkQueue(),
                'storage'  => $this->checkStorage(),
            ],
        ]);
    }

    private function checkDatabase(): array
    {
        try {
            DB::connection()->getPdo();
            return ['status' => 'ok', 'driver' => config('database.default')];
        } catch (\Throwable $e) {
            return ['status' => 'error', 'message' => $e->getMessage()];
        }
    }

    private function checkCache(): array
    {
        try {
            cache()->set('health_check', true, 1);
            return ['status' => 'ok', 'driver' => config('cache.default')];
        } catch (\Throwable $e) {
            return ['status' => 'error', 'message' => $e->getMessage()];
        }
    }

    private function checkQueue(): array
    {
        return [
            'status'  => 'ok',
            'pending' => DB::table('jobs')->count(),
            'failed'  => DB::table('failed_jobs')->count(),
        ];
    }

    private function checkStorage(): array
    {
        $path = storage_path();
        return [
            'status'    => 'ok',
            'writable'  => is_writable($path),
            'free_bytes' => disk_free_space($path),
        ];
    }

    private function dbSize(): string
    {
        try {
            if (config('database.default') === 'sqlite') {
                $size = filesize(database_path('database.sqlite'));
                return $this->formatBytes($size);
            }
            return '—';
        } catch (\Throwable) {
            return '—';
        }
    }

    private function formatBytes(int $bytes): string
    {
        $units = ['B', 'KB', 'MB', 'GB'];
        $i = floor(log($bytes, 1024));
        return round($bytes / (1024 ** $i), 2) . ' ' . $units[$i];
    }
}