<?php

namespace App\Logging;

use Monolog\Handler\AbstractProcessingHandler;
use Monolog\Logger;
use Aws\CloudWatchLogs\CloudWatchLogsClient;
use Aws\CloudWatchLogs\Exception\CloudWatchLogsException;

class CloudWatchHandler extends AbstractProcessingHandler
{
    protected $client;
    protected $groupName;

    public function __construct(CloudWatchLogsClient $client, $groupName, $level = Logger::INFO, $bubble = true)
    {
        parent::__construct($level, $bubble);
        $this->client = $client;
        $this->groupName = $groupName;
    }

    protected function write(array $record){
        // 1. Determine Stream Name from Context (set in Middleware)
        $streamName = isset($record['context']['stream']) 
            ? $record['context']['stream'] 
            : _env('CLOUDWATCH_CENTRAL_STREAM', 'centralized-admin-audit-logs');

        unset($record['formatted']);

        // 2. Format the message
        $message = json_encode($record);

        // 3. Prepare Log Event
        $params = [
            'logGroupName' => $this->groupName,
            'logStreamName' => $streamName,
            'logEvents' => [
                [
                    'timestamp' => round(microtime(true) * 1000),
                    'message' => $message
                ]
            ]
        ];

        try {
            $this->client->putLogEvents($params);
        } catch (CloudWatchLogsException $e) {
            // Check if error is due to missing Log Stream
            if ($e->getAwsErrorCode() === 'ResourceNotFoundException') {
                $this->createStream($streamName);
                // Retry once
                try {
                    $this->client->putLogEvents($params);
                } catch (\Exception $retryException) {
                    // Fallback to local log if retry fails
                    error_log('Audit Log Failed: ' . $retryException->getMessage());
                }
            }
        } catch (\Exception $e) {
            // Fail silently or log to default error log to avoid breaking app
            error_log('Audit Log Integration Error: ' . $e->getMessage());
        }
    }

    protected function createStream($streamName){
        try {
            $this->client->createLogStream([
                'logGroupName' => $this->groupName,
                'logStreamName' => $streamName
            ]);
        } catch (\Exception $e) {
            // Stream might have been created concurrently
        }
    }
}