<?php

namespace App\Http\Controllers\Api;

use Illuminate\Http\Response as HttpResponse;
use Symfony\Component\HttpFoundation\Response;
use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;

class FilesController extends BaseApiController
{
    protected array $allowedExtensions = ['jpg', 'jpeg', 'png', 'webp', 'gif', 'pdf'];

    public function receipt(string $name)
    {
        // 1) Path traversal guard
        if ($name !== basename($name)) {
            return $this->respondError('Invalid filename', Response::HTTP_BAD_REQUEST);
        }

        // 2) Allow-list extensions (optional but safer)
        $ext = strtolower(pathinfo($name, PATHINFO_EXTENSION));
        if (!in_array($ext, $this->allowedExtensions, true)) {
            throw new NotFoundHttpException();
        }

        // 3) Build path under storage/app/uploads/receipts
        $path = $this->storagePath("uploads/receipts/{$name}");

        if (!is_file($path)) {
            throw new NotFoundHttpException();
        }

        return $this->streamFile($path, $name);
    }

    public function reimb(string $name)
    {
        // 1) Path traversal guard
        if ($name !== basename($name)) {
            return $this->respondError('Invalid filename', Response::HTTP_BAD_REQUEST);
        }

        // 2) Allow-list extensions
        $ext = strtolower(pathinfo($name, PATHINFO_EXTENSION));
        if (!in_array($ext, $this->allowedExtensions, true)) {
            throw new NotFoundHttpException();
        }

        // 3) Build path under storage/app/uploads/reimbursements
        $path = $this->storagePath("uploads/reimbursements/{$name}");

        if (!is_file($path)) {
            throw new NotFoundHttpException();
        }

        return $this->streamFile($path, $name);
    }

    /**
     * Alias for reimb() for backward compatibility
     */
    public function reimbursement(string $name)
    {
        return $this->reimb($name);
    }

    public function index()
    {
        $type = $this->request->getGet('type') ?? 'receipts';
        $allowedTypes = ['receipts', 'reimbursements', 'checks'];

        if (!in_array($type, $allowedTypes, true)) {
            return $this->respondError('Invalid file type', Response::HTTP_BAD_REQUEST);
        }

        try {
            $path = $this->storagePath("uploads/{$type}/");
            $files = [];

            if (is_dir($path)) {
                foreach (scandir($path) as $file) {
                    if ($file === '.' || $file === '..') {
                        continue;
                    }
                    $filePath = $path . $file;
                    if (!is_file($filePath)) {
                        continue;
                    }
                    $files[] = [
                        'name' => $file,
                        'size' => filesize($filePath),
                        'modified' => date('Y-m-d H:i:s', filemtime($filePath)),
                    ];
                }
            }

            return $this->success([
                'type' => $type,
                'files' => $files,
                'count' => count($files),
            ], 'Files retrieved successfully');
        } catch (\Throwable $e) {
            log_message('error', 'Files list error: ' . $e->getMessage());
            return $this->respondError('Failed to retrieve files', Response::HTTP_INTERNAL_SERVER_ERROR);
        }
    }

    protected function streamFile(string $path, string $name): HttpResponse
    {
        // 4) MIME detection (finfo is more reliable than mime_content_type)
        $mime = 'application/octet-stream';
        if (function_exists('finfo_open')) {
            $fi = finfo_open(FILEINFO_MIME_TYPE);
            if ($fi) {
                $detected = finfo_file($fi, $path);
                if ($detected) {
                    $mime = $detected;
                }
                finfo_close($fi);
            }
        } elseif (function_exists('mime_content_type')) {
            $mime = mime_content_type($path) ?: $mime;
        }

        // 5) Caching (ETag + Last-Modified) and 304 support
        $mtime = filemtime($path) ?: time();
        $size = filesize($path) ?: 0;
        $etag = md5($name . '|' . $mtime . '|' . $size);

        $ifNoneMatch = trim($this->laravelRequest->header('If-None-Match', ''), '"');
        $ifModifiedSince = $this->laravelRequest->header('If-Modified-Since');
        $imsTime = $ifModifiedSince ? strtotime($ifModifiedSince) : false;

        if (($ifNoneMatch && $ifNoneMatch === $etag) ||
            ($imsTime !== false && $imsTime >= $mtime)
        ) {
            return response('', Response::HTTP_NOT_MODIFIED)
                ->header('ETag', $etag)
                ->header('Last-Modified', gmdate('D, d M Y H:i:s', $mtime) . ' GMT');
        }

        // 6) Stream the file inline
        return response()->make(file_get_contents($path), Response::HTTP_OK, [
            'Content-Type' => $mime,
            'X-Content-Type-Options' => 'nosniff',
            'Content-Disposition' => 'inline; filename="' . $name . '"',
            'Content-Length' => (string) $size,
            'ETag' => $etag,
            'Last-Modified' => gmdate('D, d M Y H:i:s', $mtime) . ' GMT',
            'Cache-Control' => 'public, max-age=86400',
        ]);
    }

    protected function storagePath(string $relative): string
    {
        return storage_path('app/' . $relative);
    }

    protected function isAllowedExtension(string $name): bool
    {
        $ext = strtolower(pathinfo($name, PATHINFO_EXTENSION));
        return in_array($ext, $this->allowedExtensions, true);
    }

    protected function detectMime(string $path): string
    {
        if (function_exists('finfo_open')) {
            $finfo = finfo_open(FILEINFO_MIME_TYPE);
            if ($finfo) {
                $mime = finfo_file($finfo, $path);
                finfo_close($finfo);
                if ($mime) {
                    return $mime;
                }
            }
        } elseif (function_exists('mime_content_type')) {
            $mime = mime_content_type($path);
            if ($mime) {
                return $mime;
            }
        }
        return 'application/octet-stream';
    }
}