<?php

declare(strict_types=1);

namespace Classifier\Lib\Discriminant;

class AlertClassifier
{
    /** @var array<string,int> */
    private $dictionary;

    /** @var int */
    private $threshold;

    /**
     * @param array<string,int> $dictionary eg: [
     *  'alerte' => 50, 'population' => 30 ...
     * ]
     * @param int $threshold Le score à partir duquel on est "sûr" à 100%
     */
    public function __construct(array $dictionary, int $threshold = 100)
    {
        $this->dictionary = $dictionary;
        $this->threshold  = $threshold;
    }

    /**
     * @param string[] $cleanWords
     * @return float Indice de confiance entre 0 et 1
     */
    public function getConfidenceScore(array $cleanWords): float
    {
        $totalScore = 0;

        foreach ($this->dictionary as $keyword => $weight) {
            $bestMatch = 0;

            foreach ($cleanWords as $word) {
                $distance = levenshtein($keyword, $word);

                // * Calcul du ratio de similitude (0 à 1)
                $maxLen = max(strlen($keyword), strlen($word));
                if ($maxLen === 0) {
                    continue;
                }

                $similarity = 1 - ($distance / $maxLen);

                // * On ne garde que si c'est très proche (ex: > 80%)
                if ($similarity > 0.8) {
                    $bestMatch = max($bestMatch, $similarity);
                }
            }

            // * Ajout du poids pondéré par la qualité de la correspondance
            $totalScore += ($bestMatch * $weight);
        }

        // * Normalisation : on plafonne à 1 (100%)
        $confidence = $totalScore / $this->threshold;
        return min(1.0, $confidence);
    }
}