<?php

declare(strict_types=1);

namespace Mod\Proxy\Services;

use Illuminate\Support\Facades\Cache;

/**
 * Tracks API usage per key — bytes for proxy, requests for SEO.
 *
 *   $meter = app(UsageMeter::class);
 *   $meter->recordBytes('api-key-123', 1048576); // 1MB
 *   $meter->recordRequest('api-key-456');
 *   $usage = $meter->getUsage('api-key-123');
 */
class UsageMeter
{
    /**
     *   $meter->recordBytes('key', 1048576);
     */
    public function recordBytes(string $apiKey, int $bytes): void
    {
        $key = "usage:bytes:{$apiKey}";
        $current = (int) Cache::get($key, 0);
        Cache::put($key, $current + $bytes, 86400 * 30); // 30 day window
    }

    /**
     *   $meter->recordRequest('key');
     */
    public function recordRequest(string $apiKey): void
    {
        $key = "usage:requests:{$apiKey}";
        $current = (int) Cache::get($key, 0);
        Cache::put($key, $current + 1, 86400 * 30);
    }

    /**
     *   $usage = $meter->getUsage('key');
     *   // ['bytes' => 104857600, 'requests' => 523, 'gb' => 0.1]
     */
    public function getUsage(string $apiKey): array
    {
        $bytes = (int) Cache::get("usage:bytes:{$apiKey}", 0);
        $requests = (int) Cache::get("usage:requests:{$apiKey}", 0);

        return [
            'bytes' => $bytes,
            'gb' => round($bytes / (1024 * 1024 * 1024), 4),
            'requests' => $requests,
        ];
    }

    /**
     *   $meter->resetUsage('key');
     */
    public function resetUsage(string $apiKey): void
    {
        Cache::forget("usage:bytes:{$apiKey}");
        Cache::forget("usage:requests:{$apiKey}");
    }
}