<?php

namespace App\Services;

use App\Models\Ticket;
use App\Services\Llm\LlmClientInterface;
use Illuminate\Support\Str;

class KnowledgeGapService
{
    public const CONFIDENCE_THRESHOLD = 0.45;

    public function __construct(
        private readonly LlmClientInterface $llmClient,
        private readonly AppSettingsService $settings,
    ) {}

    public function shouldCreateDraft(Ticket $ticket, array $result): bool
    {
        $confidence = (float) ($result['confidence'] ?? 0);
        if ($confidence < self::CONFIDENCE_THRESHOLD) {
            return true;
        }

        $explanation = mb_strtolower((string) ($result['explanation'] ?? ''));
        $signals = ['does not contain', 'niet relevant', 'mismatch', 'no article', 'onvoldoende', 'server outage'];
        foreach ($signals as $signal) {
            if (str_contains($explanation, $signal)) {
                return true;
            }
        }

        return false;
    }

    public function suggestArticleDraft(Ticket $ticket, array $result): array
    {
        $question = $ticket->normalized_message ?: $ticket->message;
        $language = (string) ($ticket->redaction_report['language'] ?? 'nl');
        $topCandidates = json_encode($result['top_3_candidates'] ?? [], JSON_UNESCAPED_UNICODE);

        $basePrompt = $this->settings->getPrompt('knowledge_gap', 'Create a draft knowledge base article suggestion. Return JSON only with keys: title, content.');
        $prompt = $basePrompt."\n\n".
            "Klantvraag:\n{$question}\n\n".
            "Originele taal: {$language}. Schrijf titel en inhoud in deze taal.\n\n".
            'Aanspreekvorm: '.$this->settings->toneInstruction()."\n\n".
            "Huidige kandidaten (mogelijk onvoldoende):\n{$topCandidates}\n\n".
            'Content moet praktisch zijn met duidelijke stappen.';

        $title = 'Concept: '.Str::limit($question, 80, '');
        $content = "Deze vraag kon nog niet goed worden beantwoord vanuit de huidige kennisbank.\n\n".
            "Klantvraag:\n".$question."\n\n".
            'Actie: supportmedewerker vult dit artikel aan met definitieve stappen en context.';

        try {
            $raw = trim($this->llmClient->generate($prompt, ['expect_json' => true, 'task' => 'knowledge_gap']));
            $decoded = json_decode($raw, true);
            if (is_array($decoded)) {
                $title = trim((string) ($decoded['title'] ?? $title));
                $content = trim((string) ($decoded['content'] ?? $content));
            }
        } catch (\Throwable) {
        }

        return [
            'title' => $title,
            'content' => $content,
        ];
    }
}