Add printer discovery and self-update; v0.2.1

- Find… button lists serial ports and paired Bluetooth devices (bluetoothctl
  on Linux, PnP device properties on Windows) and fills in the connection
- Startup check against the releases API; update bar with Update now /
  Release notes / Later / Skip this version; manual check via the version
  link. Standalone builds download the new executable and replace
  themselves via a small handoff script, then relaunch
- README: connection setup and updater notes

label_app.py

@@ -5,10 +5,15 @@ select, drag to move, arrow keys to nudge, rotate/resize from the side panel.
 """
 
 import json
+import os
 import re
+import subprocess
 import sys
+import tempfile
 import threading
 import tkinter as tk
+import urllib.request
+import webbrowser
 from dataclasses import asdict, dataclass, field
 from pathlib import Path
 from tkinter import filedialog
@@ -16,6 +21,7 @@ from tkinter import filedialog
 import emoji_data_python
 import ttkbootstrap as ttk
 from PIL import Image, ImageDraw, ImageFont, ImageOps, ImageTk
+from serial.tools import list_ports
 from ttkbootstrap.dialogs import Messagebox
 
 from niimprint import (
@@ -27,6 +33,12 @@ from niimprint import (
     prepare_print,
 )
 
+APP_VERSION = "0.2.1"
+UPDATE_REPO = "gracious/NIIMBOT-D101"
+UPDATE_API = f"https://git.gracious.one/api/v1/repos/{UPDATE_REPO}/releases/latest"
+UPDATE_ASSET = "NiimbotLabel.exe" if sys.platform == "win32" else "NiimbotLabel"
+FROZEN = bool(getattr(sys, "frozen", False))  # running from a PyInstaller bundle
+
 PX_PER_MM = 8
 SETTINGS_PATH = Path.home() / ".config" / "niimprint-label" / "settings.json"
 DEFAULT_ADDR = ""  # printer Bluetooth MAC / serial port; remembered once entered
@@ -297,6 +309,136 @@ class Design:
         )
 
 
+# --------------------------------------------------------------------------- devices
+
+
+def _run(cmd: list[str], timeout: float = 10) -> str:
+    try:
+        kw = {}
+        if sys.platform == "win32":
+            kw["creationflags"] = 0x08000000  # CREATE_NO_WINDOW
+        return subprocess.run(
+            cmd, capture_output=True, text=True, timeout=timeout, **kw
+        ).stdout
+    except (OSError, subprocess.SubprocessError):
+        return ""
+
+
+def find_devices() -> list[tuple[str, str, str]]:
+    """Return [(conn, address, description)] for serial ports and paired BT devices."""
+    found = []
+    for port in list_ports.comports():
+        if port.description and port.description != "n/a":  # skip legacy ttyS*
+            found.append(("usb", port.device, port.description))
+    if sys.platform == "win32":
+        ps = (
+            "Get-PnpDevice -Class Bluetooth -Status OK | ForEach-Object { "
+            "$a = (Get-PnpDeviceProperty -InstanceId $_.InstanceId "
+            "-KeyName DEVPKEY_Bluetooth_DeviceAddress -ErrorAction SilentlyContinue).Data; "
+            'if ($a) { "$a|$($_.FriendlyName)" } }'
+        )
+        for line in _run(["powershell", "-NoProfile", "-Command", ps]).splitlines():
+            if "|" in line:
+                raw, name = line.strip().split("|", 1)
+                raw = raw.replace(":", "").replace("-", "").upper()
+                if len(raw) == 12:
+                    mac = ":".join(raw[i : i + 2] for i in range(0, 12, 2))
+                    found.append(("bluetooth", mac, name))
+    elif sys.platform.startswith("linux"):
+        for line in _run(["bluetoothctl", "devices"]).splitlines():
+            parts = line.split(" ", 2)
+            if len(parts) == 3 and parts[0] == "Device":
+                found.append(("bluetooth", parts[1], parts[2]))
+    return found
+
+
+def _looks_like_printer(desc: str) -> bool:
+    d = desc.lower()
+    return any(k in d for k in ("niimbot", "b21", "b1-", "b18", "d11", "d101", "d110"))
+
+
+# --------------------------------------------------------------------------- updates
+
+
+def _version_tuple(v: str) -> tuple[int, ...]:
+    return tuple(int(x) for x in re.findall(r"\d+", v)[:3]) or (0,)
+
+
+def check_for_update() -> dict | None:
+    """Query the releases API; return {version, url, asset_url, notes} if newer."""
+    req = urllib.request.Request(
+        UPDATE_API, headers={"User-Agent": f"NiimbotLabel/{APP_VERSION}"}
+    )
+    with urllib.request.urlopen(req, timeout=8) as resp:
+        rel = json.load(resp)
+    version = rel.get("tag_name", "").lstrip("v")
+    if _version_tuple(version) <= _version_tuple(APP_VERSION):
+        return None
+    asset_url = next(
+        (
+            a["browser_download_url"]
+            for a in rel.get("assets", [])
+            if a["name"] == UPDATE_ASSET
+        ),
+        None,
+    )
+    return {
+        "version": version,
+        "url": rel.get("html_url", ""),
+        "asset_url": asset_url,
+        "notes": rel.get("body", ""),
+    }
+
+
+def download(url: str, dest: Path, progress=None):
+    req = urllib.request.Request(
+        url, headers={"User-Agent": f"NiimbotLabel/{APP_VERSION}"}
+    )
+    with urllib.request.urlopen(req, timeout=30) as resp, open(dest, "wb") as out:
+        total = int(resp.headers.get("Content-Length") or 0)
+        done = 0
+        while chunk := resp.read(256 * 1024):
+            out.write(chunk)
+            done += len(chunk)
+            if progress:
+                progress(done, total)
+
+
+def swap_executable_and_restart(new_file: Path):
+    """Replace the running bundle with new_file once we exit, then relaunch."""
+    exe = Path(sys.executable)
+    pid = os.getpid()
+    if sys.platform == "win32":
+        script = exe.parent / "NiimbotLabel-update.bat"
+        script.write_text(
+            "@echo off\r\n"
+            f':wait\r\ntasklist /FI "PID eq {pid}" | find "{pid}" >nul && '
+            "(timeout /t 1 /nobreak >nul & goto wait)\r\n"
+            f'move /y "{new_file}" "{exe}" >nul\r\n'
+            f'start "" "{exe}"\r\n'
+            'del "%~f0"\r\n'
+        )
+        subprocess.Popen(
+            ["cmd", "/c", str(script)],
+            creationflags=0x00000008
+            | 0x00000200,  # DETACHED_PROCESS | NEW_PROCESS_GROUP
+            close_fds=True,
+        )
+    else:
+        script = exe.parent / ".niimbotlabel-update.sh"
+        script.write_text(
+            "#!/bin/sh\n"
+            f"while kill -0 {pid} 2>/dev/null; do sleep 0.5; done\n"
+            f"mv -f '{new_file}' '{exe}' && chmod +x '{exe}'\n"
+            f"rm -f '{script}'\n"
+            f"exec '{exe}'\n"
+        )
+        script.chmod(0o755)
+        subprocess.Popen(
+            ["/bin/sh", str(script)], start_new_session=True, close_fds=True
+        )
+
+
 # --------------------------------------------------------------------------- app
 
 
@@ -357,6 +499,7 @@ class LabelApp(ttk.Window):
         for var in (self.model, self.conn, self.addr):
             var.trace_add("write", lambda *_: self._disconnect())
         self._apply_preset()
+        self.after(1500, self.check_updates)
         if not self.design.items:
             self.add_text("Hello 👋")
         self._select(self.design.items[-1])
@@ -365,6 +508,30 @@ class LabelApp(ttk.Window):
     # ---- UI construction
 
     def _build_ui(self):
+        self.update_bar = ttk.Frame(self, padding=(12, 6), bootstyle="info")
+        self.update_label = ttk.Label(self.update_bar, bootstyle="inverse-info")
+        self.update_label.pack(side="left")
+        ttk.Button(
+            self.update_bar, text="Skip this version", bootstyle="info-link",
+            command=lambda: self._dismiss_update(skip=True),
+        ).pack(side="right")  # fmt: skip
+        ttk.Button(
+            self.update_bar, text="Later", bootstyle="info-link",
+            command=self._dismiss_update,
+        ).pack(side="right")  # fmt: skip
+        self.update_notes_btn = ttk.Button(
+            self.update_bar, text="Release notes", bootstyle="info-outline",
+            command=lambda: webbrowser.open(self._update["url"]),
+        )  # fmt: skip
+        self.update_notes_btn.pack(side="right", padx=(0, 8))
+        self.update_btn = ttk.Button(
+            self.update_bar,
+            text="Update now",
+            bootstyle="light",
+            command=self.apply_update,
+        )
+        self.update_btn.pack(side="right", padx=(0, 8))
+
         root = ttk.Frame(self, padding=12)
         root.pack(fill="both", expand=True)
         root.columnconfigure(1, weight=1)
@@ -524,9 +691,12 @@ class LabelApp(ttk.Window):
             width=9,
         ).grid(row=0, column=3, sticky="w")
         ttk.Label(box, text="Address").grid(row=1, column=0, sticky="w")
-        ttk.Entry(box, textvariable=self.addr, width=22).grid(
+        ttk.Entry(box, textvariable=self.addr, width=16).grid(
-            row=1, column=1, columnspan=3, sticky="we", pady=(4, 0)
+            row=1, column=1, columnspan=2, sticky="we", pady=(4, 0)
         )
+        ttk.Button(
+            box, text="Find…", command=self.find_printer, bootstyle="secondary-outline"
+        ).grid(row=1, column=3, sticky="e", padx=(6, 0), pady=(4, 0))
         ttk.Label(box, text="Density").grid(row=2, column=0, sticky="w")
         ttk.Spinbox(box, from_=1, to=5, textvariable=self.density, width=4).grid(
             row=2, column=1, sticky="w", pady=(4, 0)
@@ -662,6 +832,10 @@ class LabelApp(ttk.Window):
         ttk.Label(bar, textvariable=self.status, bootstyle="secondary").pack(
             side="right", padx=(0, 12)
         )
+        ttk.Button(
+            bar, text=f"v{APP_VERSION}", bootstyle="secondary-link",
+            command=lambda: self.check_updates(manual=True),
+        ).pack(side="left", padx=(12, 0))  # fmt: skip
 
     # ---- theme
 
@@ -924,6 +1098,155 @@ class LabelApp(ttk.Window):
             self.design.render()[0].convert("1").save(path)
             self.status.set(f"Saved {Path(path).name}")
 
+    # ---- device discovery
+
+    def find_printer(self):
+        """List serial ports and paired Bluetooth devices; pick one to fill in."""
+        self.status.set("Searching for devices…")
+        self.update_idletasks()
+        devices = find_devices()
+        self.status.set("Ready")
+        if not devices:
+            Messagebox.show_info(
+                "No serial ports or paired Bluetooth devices found.\n\n"
+                "Pair the printer in your OS Bluetooth settings first, or plug in USB.",
+                "Find printer",
+                parent=self,
+            )
+            return
+        devices.sort(key=lambda d: (not _looks_like_printer(d[2]), d[0], d[2]))
+
+        win = ttk.Toplevel(self)
+        win.title("Select printer")
+        win.transient(self)
+        win.resizable(False, False)
+        frame = ttk.Frame(win, padding=12)
+        frame.pack(fill="both", expand=True)
+        ttk.Label(frame, text="Serial ports and paired Bluetooth devices:").pack(
+            anchor="w"
+        )
+        cols = ("via", "address", "name")
+        tree = ttk.Treeview(frame, columns=cols, show="headings", height=8)
+        for c, w in zip(cols, (90, 170, 320)):
+            tree.heading(c, text=c.title())
+            tree.column(c, width=w, anchor="w")
+        for conn, addr, desc in devices:
+            tag = "printer" if _looks_like_printer(desc) else ""
+            tree.insert("", "end", values=(conn, addr, desc), tags=(tag,))
+        tree.tag_configure("printer", foreground=self.style.colors.success)
+        tree.pack(fill="both", expand=True, pady=(6, 8))
+        if tree.get_children():
+            tree.selection_set(tree.get_children()[0])
+
+        def choose(_e=None):
+            sel = tree.selection()
+            if sel:
+                conn, addr, _ = tree.item(sel[0], "values")
+                self.conn.set(conn)
+                self.addr.set(addr)
+                self.status.set(f"Printer set to {addr}")
+            win.destroy()
+
+        tree.bind("<Double-1>", choose)
+        btns = ttk.Frame(frame)
+        btns.pack(fill="x")
+        ttk.Button(btns, text="Use selected", command=choose, bootstyle="primary").pack(
+            side="right"
+        )
+        ttk.Button(btns, text="Cancel", command=win.destroy, bootstyle="link").pack(
+            side="right", padx=(0, 6)
+        )
+        win.grab_set()
+
+    # ---- updates
+
+    def check_updates(self, manual=False):
+        def work():
+            try:
+                info = check_for_update()
+            except Exception as exc:  # noqa: BLE001 — offline is fine
+                self.after(0, self._update_checked, None, manual, str(exc))
+                return
+            self.after(0, self._update_checked, info, manual, None)
+
+        if manual:
+            self.status.set("Checking for updates…")
+        threading.Thread(target=work, daemon=True).start()
+
+    def _update_checked(self, info, manual, error):
+        if error:
+            if manual:
+                self.status.set("Update check failed")
+                Messagebox.show_warning(
+                    f"Could not reach the releases page:\n{error}",
+                    "Updates",
+                    parent=self,
+                )
+            return
+        if not info:
+            if manual:
+                self.status.set(f"v{APP_VERSION} is the latest version")
+            return
+        if not manual and self.settings.get("skip_version") == info["version"]:
+            return
+        self._update = info
+        self.status.set(f"Update available: v{info['version']}")
+        self.update_label.configure(
+            text=f"Version {info['version']} is available (you have {APP_VERSION})."
+        )
+        can_self_update = FROZEN and info["asset_url"]
+        self.update_btn.configure(
+            text="Update now" if can_self_update else "Download",
+            command=self.apply_update
+            if can_self_update
+            else lambda: webbrowser.open(info["url"]),
+        )
+        self.update_bar.pack(fill="x", side="top", before=self.winfo_children()[1])
+
+    def _dismiss_update(self, skip=False):
+        self.update_bar.pack_forget()
+        if skip and getattr(self, "_update", None):
+            self.settings["skip_version"] = self._update["version"]
+            self._save_settings()
+
+    def apply_update(self):
+        info = self._update
+        self.update_btn.configure(state="disabled")
+        dest = Path(tempfile.gettempdir()) / f"{UPDATE_ASSET}.new"
+
+        def progress(done, total):
+            pct = f" {done * 100 // total}%" if total else ""
+            self.after(0, self.status.set, f"Downloading v{info['version']}…{pct}")
+
+        def work():
+            try:
+                download(info["asset_url"], dest, progress)
+                if sys.platform != "win32":
+                    dest.chmod(0o755)
+                self.after(0, self._update_downloaded, dest, None)
+            except Exception as exc:  # noqa: BLE001
+                self.after(0, self._update_downloaded, dest, exc)
+
+        threading.Thread(target=work, daemon=True).start()
+
+    def _update_downloaded(self, dest: Path, exc):
+        self.update_btn.configure(state="normal")
+        if exc:
+            self.status.set("Update failed")
+            Messagebox.show_error(str(exc), "Update failed", parent=self)
+            return
+        self._save_settings()
+        try:
+            swap_executable_and_restart(dest)
+        except OSError as exc:
+            Messagebox.show_error(
+                f"Downloaded to {dest} but could not replace the program:\n{exc}",
+                "Update failed",
+                parent=self,
+            )
+            return
+        self.destroy()
+
     # ---- printing
 
     def _connect(self) -> PrinterClient:
@@ -993,6 +1316,7 @@ class LabelApp(ttk.Window):
             "addr": self.addr.get(),
             "density": self.density.get(),
             "theme": self.theme_mode,
+            "skip_version": self.settings.get("skip_version"),
             "design": self.design.to_dict(),
         }
         try:

pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "niimprint"
-version = "0.1.0"
+version = "0.2.1"
 description = ""
 authors = []
 

readme.md

@@ -13,7 +13,9 @@ Standalone builds, no Python needed — grab the latest from the [releases page]
 | `NiimbotLabel.exe` | Windows 10/11 x64 |
 | `NiimbotLabel` | Linux x64 (needs a system Tcl/Tk) |
 
-Pair the printer over Bluetooth in your OS first, then enter its MAC address in the app's *Printer* box (see [Bluetooth connection](#bluetooth-connection) for which address to use). For USB, leave the address blank to auto-detect, or enter the port (`/dev/ttyACM0`, `COM3`).
+Pair the printer in your OS Bluetooth settings first, then click **Find…** in the app's *Printer* box: it lists paired Bluetooth devices and serial ports, with the printer highlighted — double-click it and you're set. (On Windows the paired printer also appears as a *Standard Serial over Bluetooth* `COMx` port, which works just as well.) You can also type the address yourself: a MAC like `AA:BB:CC:DD:EE:FF` for Bluetooth, or a port (`/dev/ttyACM0`, `COM3`) for USB — blank auto-detects a single USB printer.
+
+The app checks the releases page on startup and offers to update itself when a newer version is published.
 
 ## Supported printers
 
@@ -146,10 +148,12 @@ The 40 × 12 mm label above, exactly as sent to the printer (320 × 96 px, 1-bit
 
 ### Printing & files
 
+- **Find…** — lists paired Bluetooth devices (via `bluetoothctl` on Linux, PnP device properties on Windows) and serial ports; pick the printer to fill in *Via* and *Address*.
 - **Print** — connects lazily and prints in the background; *Copies* repeats the label. Errors show in a dialog.
 - **Save PNG…** exports the 1-bit image; **Save… / Open…** store the design as JSON; **New** clears the label.
 - Printer model, connection, address, density, theme, and the last design are remembered in `~/.config/niimprint-label/settings.json`.
 - ☾ / ☀ toggles light and dark themes ([ttkbootstrap](https://ttkbootstrap.readthedocs.io) *flatly* / *darkly*).
+- **Updates** — on startup the app asks the releases API for the latest version (one small request, no other data sent). If there is a newer one, a bar offers *Update now*: the standalone build downloads the new executable and replaces itself, a source checkout gets a link to the release. The version link in the bottom bar checks manually.
 
 ### Library use
 
@@ -175,7 +179,7 @@ A PyInstaller spec (`label_app.spec`) bundles the app, fonts, emoji data and the
 .\build-windows.ps1
 ```
 
-produces `dist\NiimbotLabel.exe` (~30 MB, no installation needed). Bluetooth uses the Windows RFCOMM socket API, so pair the printer in Windows Bluetooth settings first, then enter its MAC address in the app. For USB, enter the `COMx` port or leave the address blank to auto-detect.
+produces `dist\NiimbotLabel.exe` (~30 MB, no installation needed). Bluetooth uses the Windows RFCOMM socket API: pair the printer in Windows Bluetooth settings, then use **Find…** in the app (or enter the MAC / `COMx` port by hand).
 
 `assets/win/fribidi.dll` is bundled because Pillow's Windows wheel needs it for emoji sequences (flags, skin tones, 🧑‍💻-style ZWJ emoji); see `assets/win/README.md`.