<?php
namespace App\Controllers\Sistema;

use App\Controllers\BaseController;
use App\Models\Sistema\BackupModel;
use phpseclib3\Net\SFTP;
use ZipArchive;

class Backups extends BaseController
{
    protected $backupModel;

    public function __construct()
    {
        $this->backupModel = new BackupModel();
    }

    public function index()
    {
        helper('filesystem');

        $entries = $this->backupModel->orderBy('created_at', 'DESC')->findAll();

        $backups = [];
        foreach ($entries as $entry) {
            $file = $entry['filename'];
            $localPath = $entry['path_local'];
            $remotePath = $entry['path_remote'];

            $isLocal = $localPath && file_exists($localPath);
            $isRemote = !empty($remotePath);

            if ($isLocal) {
                $fecha = date('Y-m-d H:i', filemtime($localPath));
                $tamano = filesize($localPath);
                $tamanoFmt = number_format($tamano / 1024, 2) . ' KB';

                // Actualizar la BD si ha cambiado
                if ($entry['size'] != $tamano) {
                    $this->backupModel->update($entry['id'], [
                        'size' => $tamano,
                    ]);
                }

            } else {
                $fecha = $entry['created_at'] ?? '-';
                $tamano = $entry['size'] ?? null;
                $tamanoFmt = $tamano ? number_format($tamano / 1024, 2) . ' KB' : '-';
            }

            $backups[] = [
                'id' => $entry['id'],
                'filename' => $file,
                'fecha' => $fecha,
                'tamano' => $tamanoFmt,
                'local' => $isLocal,
                'remoto' => $isRemote,
            ];
        }

        return view('themes/vuexy/form/backups/backupList', ['backups' => $backups]);
    }


    public function create()
    {
        helper('filesystem');

        $timestamp = date('Ymd_His');
        $sqlFilename = "backup_{$timestamp}.sql";
        $zipFilename = "backup_{$timestamp}.zip";
        $sqlPath = WRITEPATH . 'backups/' . $sqlFilename;
        $zipPath = WRITEPATH . 'backups/' . $zipFilename;

        $dbConfig = config('Database')->default;
        $host = $dbConfig['hostname'];
        $username = $dbConfig['username'];
        $password = $dbConfig['password'];
        $database = $dbConfig['database'];

        $command = "mysqldump -h {$host} -u{$username} -p'{$password}' {$database} > {$sqlPath}";
        system($command, $retval);

        if ($retval !== 0) {
            throw new \RuntimeException("Error al crear el backup.");
        }

        // Crear el zip
        $zip = new ZipArchive();
        if ($zip->open($zipPath, ZipArchive::CREATE) === TRUE) {
            $zip->addFile($sqlPath, $sqlFilename);
            $zip->close();
            unlink($sqlPath); // eliminar el .sql original
        } else {
            throw new \RuntimeException("Error al comprimir el backup.");
        }

        // Insertar en BD
        $backupId = $this->backupModel->insert([
            'filename' => $zipFilename,
            'type' => 'manual',
            'path_local' => $zipPath,
            'path_remote' => null,
            'size' => filesize($zipPath),
            'status' => 'pendiente',
            'created_at' => date('Y-m-d H:i:s')
        ], true);

        // Enviar a SFTP
        $this->sendToSFTP($zipPath, $zipFilename);

        // Actualizar BD
        $remotePath = "/users/erp2019/backups_erp/" . $zipFilename;
        $this->backupModel->update($backupId, [
            'path_remote' => $remotePath,
            'status' => 'subido'
        ]);

        return redirect()->to(route_to('backupsList'))->with('message', 'Backup creado, comprimido y enviado.');
    }

    public function restoreLocal($file)
    {
        $path = WRITEPATH . 'backups/' . $file;
        if (!file_exists($path)) {
            throw new \CodeIgniter\Exceptions\PageNotFoundException("Backup no encontrado.");
        }

        $zip = new ZipArchive();
        if ($zip->open($path) === TRUE) {
            $extractPath = WRITEPATH . 'backups/tmp_restore/';
            if (!is_dir($extractPath)) {
                mkdir($extractPath, 0775, true);
            }
            $zip->extractTo($extractPath);
            $zip->close();

            $sqlFiles = glob($extractPath . '*.sql');
            if (count($sqlFiles) === 0) {
                throw new \RuntimeException("No se encontró ningún archivo .sql en el ZIP");
            }

            $db = \Config\Database::connect();
            $sql = file_get_contents($sqlFiles[0]);
            $db->query('SET FOREIGN_KEY_CHECKS=0;');
            $db->query($sql);
            $db->query('SET FOREIGN_KEY_CHECKS=1;');

            array_map('unlink', glob($extractPath . '*'));
            rmdir($extractPath);

            return redirect()->to('/backups')->with('message', 'Backup restaurado correctamente.');
        } else {
            throw new \RuntimeException("No se pudo abrir el archivo ZIP");
        }
    }

    public function deleteLocal($id)
    {
        $backup = $this->backupModel->find($id);
        if ($backup && $backup['path_local'] && file_exists($backup['path_local'])) {
            unlink($backup['path_local']);
            $this->backupModel->update($id, ['path_local' => null]);
            return redirect()->to(route_to('backupsList'))->with('message', 'Backup local eliminado.');
        }
        return redirect()->to(route_to('backupsList'))->with('error', 'Archivo no encontrado.');
    }

    public function restoreRemote($filename)
    {
        helper('filesystem');

        // Buscar el backup en la base de datos
        $backup = $this->backupModel->where('filename', $filename)->first();

        if (!$backup || empty($backup['path_remote'])) {
            return redirect()->to(route_to('backupsList'))->with('error', 'Backup remoto no encontrado en la base de datos.');
        }

        // Parámetros SFTP
        $sftpHost = 'sftp.hidrive.ionos.com';
        $sftpUser = 'erp2019';
        $sftpPass = 'Z2CjX7kd2h';
        $remotePath = $backup['path_remote'];
        $localPath = WRITEPATH . 'backups/' . $filename;

        // Conectar al SFTP
        $sftp = new SFTP($sftpHost);

        if (!$sftp->login($sftpUser, $sftpPass)) {
            return redirect()->to(route_to('backupsList'))->with('error', 'No se pudo autenticar en el servidor SFTP.');
        }

        // Descargar el archivo
        $fileContents = $sftp->get($remotePath);

        if ($fileContents === false) {
            return redirect()->to(route_to('backupsList'))->with('error', 'No se pudo descargar el archivo remoto.');
        }

        // Guardar localmente
        if (write_file($localPath, $fileContents) === false) {
            return redirect()->to(route_to('backupsList'))->with('error', 'No se pudo guardar el archivo localmente.');
        }

        // Actualizar la base de datos para marcar el archivo como local
        $this->backupModel->update($backup['id'], [
            'path_local' => $localPath,
        ]);

        // Restaurar usando el método local
        return $this->restoreLocal($filename);
    }


    private function sendToSFTP($localPath, $remoteFilename)
    {
        $sftpHost = 'sftp.hidrive.ionos.com';
        $sftpUser = 'erp2019';
        $sftpPass = 'Z2CjX7kd2h';
        $remotePath = '/users/erp2019/backups_erp/' . $remoteFilename;

        $sftp = new SFTP($sftpHost);

        if (!$sftp->login($sftpUser, $sftpPass)) {
            throw new \RuntimeException('Error de autenticación SFTP');
        }

        $fileContents = file_get_contents($localPath);

        if (!$sftp->put($remotePath, $fileContents)) {
            throw new \RuntimeException("No se pudo subir el backup al servidor SFTP.");
        }
    }
}