<?php

    /**
     * Class SFTPAccess
     *
     * @author Lucas Awade
     */
    class SFTPAccess {

        /** @conexao */
        private $connection;

        /** @sftp */
        private $sftp;

        function __construct($server, $port, $methods = null) {
            $this->connect($server, $port, $methods);
        }

        /**
         * Informa o servidor SFTP para inciar uma conexao.
         * @param string $server
         * @param string|int $port
         * @return boolean
         */
        function connect($server, $port = 22, $methods = null) {
            $this->connection = ssh2_connect($server, $port, $methods);
            if ($this->connection) {
                return true;
            } else {
                return false;
            }
        }

        /**
         * Autentica as credencias para conectar ao SFTP.
         * @param string $username
         * @param string $password
         * @return boolean
         */
        function authentication($username, $password) {
            if (ssh2_auth_password($this->connection, $username, $password)) {
                $this->sftp = ssh2_sftp($this->connection);
                if ($this->sftp) {
                    return true;
                } else {
                    return false;
                }
            } else {
                return false;
            }
        }

        /**
         * Altera o diretorio conexao inicial do servidor SFTP.
         * @param type $directory
         * @return boolean
         */
        function ch_dir($directory) {
            $stream = ssh2_exec($this->sftp, "cd {$directory}");
            $errorStream = ssh2_fetch_stream($stream, SSH2_STREAM_STDERR);
            stream_set_blocking($errorStream, true);
            $erro = trim(stream_get_contents($errorStream));

            if (!empty($erro)) {
                return false;
            }

            return true;
        }

        /**
         * Transfere os dados em modo de escrita do arquivo local para o remoto.
         * @param string $localfile
         * @param string $remotefile
         * @return boolean
         */
        function copy_file($localfile, $remotefile) {
            $stream = fopen("ssh2.sftp://{$this->sftp}{$remotefile}", "w");

            if (!$stream) {
                return false;
            }

            $file = file_get_contents($localfile);
            fwrite($stream, $file);
            fclose($stream);
            return true;
        }

    }