bambu-rs 0.1.0

//! FTPS file transfer — the printer's LAN file store.
//!
//! **Implicit** FTPS on port 990, same `bblp` + access-code auth as MQTT, and the
//! same self-signed X.509 **v1** certificate — so it shares the LAN rustls config
//! ([`crate::tls`]), which accepts any certificate (the rustls equivalent of OpenSSL
//! `CERT_NONE`), acceptable only for this LAN-direct self-signed case.

use std::path::Path;

use serde::Serialize;
use suppaftp::{RustlsConnector, RustlsFtpStream};

use crate::config::ResolvedTarget;

const FTPS_PORT: u16 = 990;
const FTP_USER: &str = "bblp";

/// One entry from a directory listing.
#[derive(Debug, Clone, PartialEq, Eq, Serialize)]
pub struct FileEntry {
    pub name: String,
    pub is_dir: bool,
    pub size: u64,
}

/// Parse one FTP `LIST` line into a [`FileEntry`]; `None` for unparseable lines
/// (a `total N` header, blank lines, the `.`/`..` pseudo-entries).
fn parse_list_line(line: &str) -> Option<FileEntry> {
    // `ls -l` prefixes a `total N` summary line; suppaftp's lenient parser would
    // otherwise turn it into a bogus entry named "total N".
    let trimmed = line.trim_start();
    if trimmed.starts_with("total ") || trimmed.is_empty() {
        return None;
    }
    let f = suppaftp::list::File::try_from(line).ok()?;
    let name = f.name().to_string();
    if name == "." || name == ".." || name.is_empty() {
        return None;
    }
    Some(FileEntry {
        name,
        is_dir: f.is_directory(),
        size: f.size() as u64,
    })
}

/// Errors from FTPS operations. Messages never include the access code.
#[derive(Debug, thiserror::Error)]
pub enum FtpError {
    #[error("TLS setup failed: {0}")]
    Tls(String),
    #[error("FTP error: {0}")]
    Ftp(String),
    #[error("local file error: {0}")]
    Io(#[from] std::io::Error),
}

/// The temp path a download streams to before the atomic rename: `<local>.part`
/// (same directory, so the rename stays on one filesystem and is atomic).
fn part_path(local: &Path) -> std::path::PathBuf {
    let mut name = local.file_name().unwrap_or_default().to_os_string();
    name.push(".part");
    local.with_file_name(name)
}

/// A one-shot FTPS client (connect → act → quit per call).
pub struct FtpsClient {
    target: ResolvedTarget,
}

impl FtpsClient {
    pub fn new(target: ResolvedTarget) -> Self {
        Self { target }
    }

    fn connect(&self) -> Result<RustlsFtpStream, FtpError> {
        let config = crate::tls::lan_client_config().map_err(|e| FtpError::Tls(e.to_string()))?;
        let mut ftp = RustlsFtpStream::connect_secure_implicit(
            (self.target.ip.as_str(), FTPS_PORT),
            RustlsConnector::from(config),
            &self.target.ip,
        )
        .map_err(|e| FtpError::Ftp(e.to_string()))?;
        ftp.login(FTP_USER, &self.target.access_code)
            .map_err(|e| FtpError::Ftp(e.to_string()))?;
        Ok(ftp)
    }

    /// List file names in `dir` (FTP `NLST`).
    pub fn list(&self, dir: &str) -> Result<Vec<String>, FtpError> {
        let mut ftp = self.connect()?;
        let names = ftp
            .nlst(Some(dir))
            .map_err(|e| FtpError::Ftp(e.to_string()))?;
        let _ = ftp.quit();
        Ok(names)
    }

    /// List `dir` with directory/size info (FTP `LIST`, parsed). Unparseable
    /// lines (e.g. a `total N` header) are skipped.
    pub fn list_entries(&self, dir: &str) -> Result<Vec<FileEntry>, FtpError> {
        let mut ftp = self.connect()?;
        let lines = ftp
            .list(Some(dir))
            .map_err(|e| FtpError::Ftp(e.to_string()))?;
        let _ = ftp.quit();
        Ok(lines.iter().filter_map(|l| parse_list_line(l)).collect())
    }

    /// Upload a local file to `remote_path` on the printer; returns bytes sent.
    pub fn upload(&self, local: &Path, remote_path: &str) -> Result<u64, FtpError> {
        let mut file = std::fs::File::open(local)?;
        let mut ftp = self.connect()?;
        let result = ftp
            .put_file(remote_path, &mut file)
            .map_err(|e| FtpError::Ftp(e.to_string()));
        let _ = ftp.quit();
        result
    }

    /// Download `remote_path` from the printer to `local`; returns bytes written.
    /// Streams (FTP `RETR`) so large files (e.g. timelapse videos) aren't held
    /// in memory. Writes to a sibling temp file and atomically renames on
    /// success, so a failed or partial transfer never clobbers an existing
    /// destination.
    pub fn download(&self, remote_path: &str, local: &Path) -> Result<u64, FtpError> {
        let tmp = part_path(local);
        let mut file = std::fs::File::create(&tmp)?;
        let mut ftp = self.connect()?;
        let result = ftp
            .retr(remote_path, |reader| {
                // The closure must return suppaftp's FtpResult; wrap any local
                // write error as a connection error so RETR is finalised cleanly.
                std::io::copy(reader, &mut file).map_err(suppaftp::FtpError::ConnectionError)
            })
            .map_err(|e| FtpError::Ftp(e.to_string()));
        let _ = ftp.quit();
        drop(file);
        match result {
            Ok(n) => {
                std::fs::rename(&tmp, local)?;
                Ok(n)
            }
            Err(e) => {
                // Leave no partial file behind on failure.
                let _ = std::fs::remove_file(&tmp);
                Err(e)
            }
        }
    }

    /// Delete `remote_path` on the printer (FTP `DELE`).
    pub fn delete(&self, remote_path: &str) -> Result<(), FtpError> {
        let mut ftp = self.connect()?;
        let result = ftp
            .rm(remote_path)
            .map_err(|e| FtpError::Ftp(e.to_string()));
        let _ = ftp.quit();
        result
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn part_path_is_a_sibling_with_a_part_suffix() {
        assert_eq!(
            part_path(Path::new("/tmp/v.mp4")),
            Path::new("/tmp/v.mp4.part")
        );
        assert_eq!(part_path(Path::new("out.jpg")), Path::new("out.jpg.part"));
    }

    #[test]
    fn parses_unix_list_lines_into_entries() {
        let dir = parse_list_line("drwxr-xr-x 2 root root 4096 Jan 01 12:00 cache").unwrap();
        assert_eq!(dir.name, "cache");
        assert!(dir.is_dir);
        let file =
            parse_list_line("-rw-r--r-- 1 root root 1234 Jan 01 12:00 coin.gcode.3mf").unwrap();
        assert_eq!(file.name, "coin.gcode.3mf");
        assert!(!file.is_dir);
        assert_eq!(file.size, 1234);
        // Pseudo-entries and headers are skipped.
        assert_eq!(parse_list_line("total 8"), None);
        assert_eq!(
            parse_list_line("drwxr-xr-x 2 root root 4096 Jan 01 12:00 ."),
            None
        );
    }
}