<?php

namespace App\Services\Documenti;

class ArchiveFileResolver
{
    /**
     * Risolve il percorso assoluto di un file allegato o documento dello stabile,
     * effettuando una ricerca euristica nelle cartelle standard (E_C, INC_EC, WA, XML, allegati, posta, etc.).
     *
     * @param string|int $codStabile
     * @param string $filename
     * @param string|null $preferredSubdir
     * @return array{
     *     filename: string,
     *     path: ?string,
     *     exists: bool,
     *     size: int,
     *     mime: string,
     *     is_pdf: bool,
     *     is_image: bool
     * }
     */
    public static function resolve(string|int $codStabile, string $filename, ?string $preferredSubdir = null): array
    {
        $filename = trim($filename);
        if ($filename === '') {
            return [
                'filename' => '',
                'path'     => null,
                'exists'   => false,
                'size'     => 0,
                'mime'     => 'application/octet-stream',
                'is_pdf'   => false,
                'is_image' => false,
            ];
        }

        $cod = str_pad((string) $codStabile, 4, '0', STR_PAD_LEFT);
        $candidateSubdirs = [
            $preferredSubdir,
            'E_C', 'e_c',
            'INC_EC', 'inc_ec',
            'allegati', 'Allegati',
            'WA', 'wa',
            'XML', 'xml',
            'posta_ordinaria', 'posta_pec', 'posta',
            'documenti', 'Documenti',
            '',
        ];
        $candidateSubdirs = array_values(array_unique(array_filter($candidateSubdirs, fn($v) => $v !== null)));

        $baseRoots = [
            "/mnt/gescon-archives/gescon/{$cod}",
            "/mnt/gescon-archives/gescon/" . ltrim((string) $codStabile, '0'),
            storage_path("app/private/amministratori/ADMX3PD9/stabili/{$cod}"),
            storage_path("app/private/amministratori/ADMX3PD9/stabili/" . ltrim((string) $codStabile, '0')),
            storage_path("app/public/stabili/{$cod}"),
            storage_path("app/public/stabili/" . ltrim((string) $codStabile, '0')),
        ];

        $foundPath = null;

        // 1. Cerca percorsi esatti
        foreach ($baseRoots as $root) {
            if (! is_dir($root)) {
                continue;
            }
            foreach ($candidateSubdirs as $sub) {
                $dir = $sub !== '' ? "{$root}/{$sub}" : $root;
                $p = "{$dir}/{$filename}";
                if (file_exists($p)) {
                    $foundPath = $p;
                    break 2;
                }
            }
        }

        // 2. Se non trovato e il file ha un'estensione, cerca case-insensitive
        if (! $foundPath) {
            $lowerName = strtolower($filename);
            foreach ($baseRoots as $root) {
                if (! is_dir($root)) {
                    continue;
                }
                foreach ($candidateSubdirs as $sub) {
                    $dir = $sub !== '' ? "{$root}/{$sub}" : $root;
                    if (is_dir($dir)) {
                        $files = @scandir($dir);
                        if (is_array($files)) {
                            foreach ($files as $f) {
                                if (strtolower($f) === $lowerName) {
                                    $foundPath = "{$dir}/{$f}";
                                    break 3;
                                }
                            }
                        }
                    }
                }
            }
        }

        $exists = $foundPath !== null && file_exists($foundPath);
        $size = $exists ? (int) @filesize($foundPath) : 0;
        $mime = 'application/octet-stream';
        $isPdf = str_ends_with(strtolower($filename), '.pdf');
        $isImg = (bool) preg_match('/\.(jpg|jpeg|png|webp|gif|bmp)$/i', $filename);

        if ($exists) {
            $finfo = @finfo_open(FILEINFO_MIME_TYPE);
            if ($finfo) {
                $detected = @finfo_file($finfo, $foundPath);
                if ($detected) {
                    $mime = $detected;
                }
                @finfo_close($finfo);
            }
        }

        if ($isPdf) {
            $mime = 'application/pdf';
        }

        return [
            'filename' => $filename,
            'path'     => $foundPath,
            'exists'   => $exists,
            'size'     => $size,
            'mime'     => $mime,
            'is_pdf'   => $isPdf,
            'is_image' => $isImg,
        ];
    }
}