<?php

namespace app\common\service\ai;

use app\common\model\ai\AiConfig;

class AiAssistantRanker
{
    public static function rank(AiAssistantTrace $trace): AiAssistantTrace
    {
        $knowledgeHits = $trace->retrievals['knowledge_hits'] ?? [];
        $preferredDomain = (string) ($trace->plan['preferred_domain'] ?? '');

        usort($knowledgeHits, static function (array $left, array $right) use ($preferredDomain) {
            $leftScore = (float) ($left['score'] ?? 0);
            $rightScore = (float) ($right['score'] ?? 0);

            if ($preferredDomain !== '') {
                if (($left['domain'] ?? '') === $preferredDomain) {
                    $leftScore += 0.05;
                }
                if (($right['domain'] ?? '') === $preferredDomain) {
                    $rightScore += 0.05;
                }
            }

            return $rightScore <=> $leftScore;
        });

        $limit = max(1, min(12, (int) AiConfig::getVal('assistant_kb_topk', '6')));
        $trace->rankedHits = array_slice($knowledgeHits, 0, $limit);

        $payload = AiAssistantContextService::composePayload(
            $trace->rankedHits,
            $trace->retrievals['match_items'] ?? [],
            $trace->retrievals['crypto_items'] ?? [],
            $trace->retrievals['web_news_items'] ?? [],
            $trace->plan
        );

        $trace->finalSources = $payload['sources'] ?? [];
        $trace->contextText = (string) ($payload['context_text'] ?? '{}');
        $trace->hasContext = !empty($payload['has_context']);

        return $trace;
    }
}