<?php
namespace App\Core;
use App\Controllers\PageController;

class Lang
{
    private string $current  = 'fr';
    private array  $supported = ['fr', 'en'];
    private array  $strings   = [];

    public function __construct()
    {
        $this->detect();
        $this->load();
    }

    private function detect(): void
    {
        $uri = $_SERVER['REQUEST_URI'] ?? '/';
        $seg = explode('/', trim($uri, '/'))[0] ?? 'fr';

        if (in_array($seg, $this->supported, true)) {
            $this->current = $seg;
        }

        if (session_status() === PHP_SESSION_NONE) {
            session_start();
        }
        $_SESSION['lang'] = $this->current;
    }

    private function load(): void
    {
        $file = dirname(__DIR__, 2) . "/lang/{$this->current}.json";
        if (file_exists($file)) {
            $this->strings = json_decode(file_get_contents($file), true) ?? [];
        }
    }

    public function t(string $key, array $replace = []): string
    {
        $parts  = explode('.', $key);
        $value  = $this->strings;

        foreach ($parts as $part) {
            if (!is_array($value) || !isset($value[$part])) {
                return $key; // Clé manquante → retourne la clé
            }
            $value = $value[$part];
        }

        $str = is_string($value) ? $value : $key;
        foreach ($replace as $k => $v) {
            $str = str_replace('{{' . $k . '}}', $v, $str);
        }

        return $str;
    }

    public function getCurrent(): string { return $this->current; }
    public function getSupported(): array { return $this->supported; }
    public function switchUrl(string $targetLang): string
{
    $uri = $_SERVER['REQUEST_URI'] ?? '/';
    $path = trim($uri, '/');
    $parts = explode('/', $path); 
    $count = count($parts);

    if ($count === 2) {
        $slug = $parts[1];
        $newSlug = PageController::getTranslatedUrlFromSlug($slug, $targetLang);
        return "/{$targetLang}/{$newSlug}";
    }

    if ($count === 3) {
        $cat = ($targetLang === 'fr') ? 'activites' : 'activities';
        $pole = $parts[2];

        return "/{$targetLang}/{$cat}/{$pole}";
    }

    if ($count >= 4) {
        $pole = $parts[2];
        $slug = $parts[3];
        $newSlug = PageController::getTranslatedUrlFromSlug($slug, $targetLang);
        $cat = ($targetLang === 'fr') ? 'activites' : 'activities';
        return "/{$targetLang}/{$cat}/{$pole}/{$newSlug}";
    }

    return '/' . $targetLang;
}
}