Say when a newer release is out, and stop there

A check on the releases page once a day: at start, on a timer while Dikte
runs, from the General tab on demand, and from `dikte update` at a terminal.
What it finds goes in the tray menu and in one notification per version, and
opens the release page.

Nothing is downloaded and nothing is installed. The four downloads are
installed four different ways and three of those belong to the platform: a
Mac bundle cannot rewrite itself while it is running, the Windows setup has
an uninstall entry of its own, an AppImage is a file kept wherever its owner
keeps it, and a checkout is updated with git. Being wrong about any one of
them means an installation somebody has to repair by hand.

Versions are compared by their numbers alone. A build off master carries the
released number with its commit after it, and that build is ahead of the
release it names rather than behind it; read as a version suffix, every
nightly would be told to go back to a release it had already passed.

The clock lives in its own file rather than in the settings, since a check
runs while the settings window may be open and a background write into
config.json is what would overwrite whatever it holds.

dikte/settings_ui.py

@@ -13,6 +13,7 @@ from PyQt6.QtWidgets import (
     QPushButton, QScrollArea, QSpinBox, QTabWidget, QVBoxLayout, QWidget,
 )
 
+from . import __version__
 from . import api
 from . import assistant
 from . import audio
@@ -21,9 +22,11 @@ from . import config as cfg
 from . import filetranscribe
 from . import ggml
 from . import hotkey
+from . import hub
 from . import ipc
 from . import meeting
 from . import paste
+from . import update
 from .filetranscribe import FileTranscriber
 from .i18n import t
 
@@ -512,11 +515,16 @@ class LocalModelBox(QGroupBox):
 
 class SettingsWindow(QDialog):
     applied = pyqtSignal()
+    # A newer release this window's own check found, so that the tray icon
+    # hears about it from here rather than waiting for its own next check.
+    update_found = pyqtSignal(object)
 
     _models_loaded = pyqtSignal(list, str)
     _transcribe_models_loaded = pyqtSignal(list, str)
     # Which key was tested, whether it worked, and what to write under it.
     _test_done = pyqtSignal(str, bool, str)
+    # The release that was found, or None, and what went wrong instead.
+    _update_checked = pyqtSignal(object, str)
 
     def __init__(self, conf, meetings=None, parent=None):
         super().__init__(parent)
@@ -533,6 +541,9 @@ class SettingsWindow(QDialog):
         self._key_fields = {}
         self._testers = {}
         self._shown_provider = ""
+        # Where "Open the release page" goes: the release itself once a check
+        # has named one, and the page that redirects to the newest until then.
+        self._release_url = update.RELEASES_PAGE
         self.transcriber = FileTranscriber(conf, self)
         self.setWindowTitle(t("Dikte Settings"))
 
@@ -567,6 +578,7 @@ class SettingsWindow(QDialog):
         self._models_loaded.connect(self._on_models_loaded)
         self._transcribe_models_loaded.connect(self._on_transcribe_models_loaded)
         self._test_done.connect(self._on_test_done)
+        self._update_checked.connect(self._on_update_checked)
         self.transcriber.progress.connect(self._on_file_progress)
         self.transcriber.finished.connect(self._on_file_finished)
         self.transcriber.failed.connect(self._on_file_failed)
@@ -698,6 +710,23 @@ class SettingsWindow(QDialog):
             t("Keep audio files ({path})", path=str(cfg.RECORDINGS_DIR))
         )
         form.addRow("", self.keep_audio)
+
+        self.update_check = QCheckBox(t("Look for a newer version once a day"))
+        self.update_check.setToolTip(
+            t("Dikte only looks. What it finds opens the release page in your "
+              "browser; it downloads and installs nothing by itself.")
+        )
+        form.addRow(t("Updates"), self.update_check)
+
+        self.update_status = WrappedLabel("")
+        self.update_page = QPushButton(t("Open the release page"))
+        self.update_page.clicked.connect(
+            lambda: QDesktopServices.openUrl(QUrl(self._release_url))
+        )
+        self.update_now = QPushButton(t("Check now"))
+        self.update_now.clicked.connect(self._check_for_update)
+        form.addRow("", self._row(self.update_status, self.update_page,
+                                  self.update_now))
         return page
 
     def _api_tab(self):
@@ -1568,6 +1597,8 @@ class SettingsWindow(QDialog):
         self.silence_db.setValue(int(conf["silence_db"]))
         self.filter_hallucinations.setChecked(conf["filter_hallucinations"])
         self.keep_audio.setChecked(conf["keep_audio"])
+        self.update_check.setChecked(conf["update_check"])
+        self._show_update(update.pending())
 
         for name, who in cfg.TRANSCRIBERS.items():
             self._key_fields[name].setText(conf[who.key])
@@ -1661,6 +1692,7 @@ class SettingsWindow(QDialog):
         conf["silence_db"] = float(self.silence_db.value())
         conf["filter_hallucinations"] = self.filter_hallucinations.isChecked()
         conf["keep_audio"] = self.keep_audio.isChecked()
+        conf["update_check"] = self.update_check.isChecked()
 
         provider = self.transcribe_provider.currentData() or "local"
         if provider in self._models:
@@ -1891,6 +1923,45 @@ class SettingsWindow(QDialog):
         button.setEnabled(True)
         answer.setText(("✓ " if ok else "✗ ") + message)
 
+    # ---- updates ---------------------------------------------------------
+
+    def _check_for_update(self):
+        """The button, which asks GitHub whatever the daily clock says."""
+        self.update_now.setEnabled(False)
+        self.update_status.setText(t("Looking…"))
+
+        def work():
+            try:
+                self._update_checked.emit(update.check(force=True), "")
+            except hub.HubError as exc:
+                self._update_checked.emit(None, str(exc))
+
+        threading.Thread(target=work, daemon=True).start()
+
+    def _on_update_checked(self, release, error):
+        self.update_now.setEnabled(True)
+        if error:
+            self.update_status.setText(error)
+            return
+        self._show_update(release, asked=True)
+        if release is not None:
+            self.update_found.emit(release)
+
+    def _show_update(self, release, asked=False):
+        """What the line under the checkbox says, and whether the page button
+        is on it. `release` is None when this build is the newest one, and
+        `asked` is what tells "nothing new" from "nobody has looked yet"."""
+        self.update_page.setVisible(release is not None)
+        if release is None:
+            self.update_status.setText(
+                t("Dikte {version} is the newest release.", version=__version__)
+                if asked else t("This is Dikte {version}.", version=__version__))
+            return
+        self._release_url = release.url
+        self.update_status.setText(
+            t("Dikte {version} is out; this is {current}.",
+              version=release.version, current=__version__))
+
     # ---- audio file ------------------------------------------------------
 
     def _choose_file(self):