<?php

/**
 * Matomo - free/libre analytics platform
 *
 * @link    https://matomo.org
 * @license https://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
 */
declare (strict_types=1);
namespace Piwik\Plugins\BotTracking;

/**
 * Detects AI chatbots and bots based on User-Agent patterns
 */
class BotDetector
{
    public const BOT_TYPE_AI_CHATBOT = 'ai_chatbot';
    /** @var null|array{bot_name: string, bot_type: string} */
    private $detectionResult;
    /**
     * AI Chatbot/Bot User-Agent patterns to detect
     *
     * @var array<string, string>
     */
    private $aiAssistantPatterns = ['ChatGPT-User' => self::BOT_TYPE_AI_CHATBOT, 'MistralAI-User' => self::BOT_TYPE_AI_CHATBOT, 'Gemini-Deep-Research' => self::BOT_TYPE_AI_CHATBOT, 'Claude-User' => self::BOT_TYPE_AI_CHATBOT, 'Perplexity-User' => self::BOT_TYPE_AI_CHATBOT, 'Google-NotebookLM' => self::BOT_TYPE_AI_CHATBOT];
    public function __construct(string $userAgent)
    {
        $this->detectionResult = $this->detect($userAgent);
    }
    /**
     * Detect if the User-Agent represents an AI chatbot or bot
     *
     * @param string $userAgent The User-Agent string to check
     * @return null|array{bot_name: string, bot_type: string} Returns array if detected, null otherwise
     */
    private function detect(string $userAgent) : ?array
    {
        if (empty($userAgent)) {
            return null;
        }
        foreach ($this->aiAssistantPatterns as $pattern => $botType) {
            if (stripos($userAgent, $pattern) !== \false) {
                return ['bot_name' => $pattern, 'bot_type' => $botType];
            }
        }
        return null;
    }
    public function isBot() : bool
    {
        return $this->detectionResult !== null;
    }
    /**
     * @return null|array{'bot_name': string, 'bot_type': string}
     */
    public function getDetectionResult() : ?array
    {
        return $this->detectionResult;
    }
}