v0.43.0: visualizer presets

Each visualizer style's settings page has a Preset drop-down and a
"Save as Preset…" button. The drop-down lists the built-in Default, your
presets, and "Edit Presets…" (rename in place, delete); it reads "Custom"
whenever the settings match no preset. Presets sync with the preferences;
the per-machine sync delay is never part of one.

tests/test_round78.py

@@ -866,3 +866,176 @@ class TestNewControls:
             return sum(QColor(img.pixel(x, y)) != QColor("white")
                        for x in range(400) for y in range(0, 400, 2))
         assert ink(0.5) < ink(1.0) < ink(2.0)
+
+
+# --------------------------------------------------------------------------
+# 8. Presets
+# --------------------------------------------------------------------------
+
+from lintunes.gui import visualizer_presets as presets
+
+
+def _combo_texts(combo):
+    return [combo.itemText(i) for i in range(combo.count())]
+
+
+class TestPresets:
+    def _dialog(self, prefs):
+        return TestPreferencesPage._dialog(None, prefs)
+
+    def test_every_style_has_a_preset_menu(self, qapp, tmp_path):
+        dialog = self._dialog(Preferences(tmp_path))
+        for style in ("bars", "radial", "laser"):
+            combo = dialog._preset_combos[style]
+            assert combo.currentText() == "Default"     # untouched = Default
+            assert _combo_texts(combo)[-1] == "Edit Presets…"
+
+    def test_changing_a_setting_reads_custom(self, qapp, tmp_path):
+        prefs = Preferences(tmp_path)
+        dialog = self._dialog(prefs)
+        dialog._spokes_slider.setValue(60)
+        assert dialog._preset_combos["radial"].currentText() == "Custom"
+        assert dialog._preset_combos["laser"].currentText() == "Default"
+
+    def test_save_and_apply(self, qapp, tmp_path):
+        prefs = Preferences(tmp_path)
+        dialog = self._dialog(prefs)
+        dialog._angle_sliders["visualizer_laser_pitch"].setValue(40)
+        dialog._grid.setChecked(True)
+        dialog._speaker.setValues(150, 300)
+        dialog._width_box.setValue(3.5)
+        dialog._ask_preset_name = lambda suggestion: "Big Tilt"
+        dialog._save_preset("laser")
+        combo = dialog._preset_combos["laser"]
+        assert combo.currentText() == "Big Tilt"
+
+        # Back to Default: every control (and setting) follows.
+        dialog._on_preset_chosen("laser", combo.findData("Default"))
+        assert prefs.get("visualizer_laser_pitch") == 0
+        assert prefs.get("visualizer_laser_grid") is False
+        assert prefs.get("visualizer_laser_width") == 1.5
+        assert dialog._speaker.values() == (0, 300)
+        assert combo.currentText() == "Default"
+
+        dialog._on_preset_chosen("laser", combo.findData("Big Tilt"))
+        assert prefs.get("visualizer_laser_pitch") == 40
+        assert prefs.get("visualizer_laser_grid") is True
+        assert prefs.get("visualizer_laser_width") == 3.5
+        assert dialog._angle_sliders["visualizer_laser_pitch"].value() == 40
+        assert dialog._speaker.values() == (150, 300)
+        assert combo.currentText() == "Big Tilt"
+
+    def test_presets_survive_a_restart(self, qapp, tmp_path):
+        prefs = Preferences(tmp_path)
+        dialog = self._dialog(prefs)
+        dialog._bars_fade_slider.setValue(20)
+        dialog._ask_preset_name = lambda suggestion: "Ghosty"
+        dialog._save_preset("bars")
+        again = self._dialog(Preferences(tmp_path))
+        assert "Ghosty" in _combo_texts(again._preset_combos["bars"])
+
+    def test_default_is_reserved(self, qapp, tmp_path):
+        prefs = Preferences(tmp_path)
+        dialog = self._dialog(prefs)
+        warned = []
+        dialog._preset_warning = warned.append
+        dialog._ask_preset_name = lambda suggestion: "Default"
+        dialog._save_preset("radial")
+        assert warned and presets.presets(prefs, "radial") == {}
+
+    def test_overwrite_asks_first(self, qapp, tmp_path):
+        prefs = Preferences(tmp_path)
+        dialog = self._dialog(prefs)
+        dialog._ask_preset_name = lambda suggestion: "Mine"
+        dialog._save_preset("radial")
+        dialog._spokes_slider.setValue(200)
+        dialog._confirm_overwrite = lambda name: False
+        dialog._save_preset("radial")
+        assert presets.presets(prefs, "radial")["Mine"][
+            "visualizer_radial_spokes"] == 120          # kept
+        dialog._confirm_overwrite = lambda name: True
+        dialog._save_preset("radial")
+        assert presets.presets(prefs, "radial")["Mine"][
+            "visualizer_radial_spokes"] == 200
+
+    def test_a_preset_only_holds_its_own_style(self, qapp, tmp_path):
+        prefs = Preferences(tmp_path)
+        presets.save(prefs, "bars", "x")
+        assert set(presets.presets(prefs, "bars")["x"]) == {"visualizer_bars_fade"}
+        assert "visualizer_sync_delay_ms" not in presets.STYLE_KEYS["laser"]
+
+    def test_an_old_preset_takes_new_settings_defaults(self, qapp, tmp_path):
+        prefs = Preferences(tmp_path)
+        prefs.set(presets.PRESETS_KEY,
+                  {"laser": {"Old": {"visualizer_laser_pitch": 20}}})
+        values = presets.values_of(prefs, "laser", "Old")
+        assert values["visualizer_laser_pitch"] == 20
+        assert values["visualizer_laser_glow"] is True       # default
+
+    def test_every_style_key_has_a_control(self, qapp, tmp_path):
+        dialog = self._dialog(Preferences(tmp_path))
+        for style, keys in presets.STYLE_KEYS.items():
+            for key in keys:
+                assert key in dialog._viz_setters or key in (
+                    "visualizer_laser_low_hz", "visualizer_laser_high_hz")
+
+
+class TestPresetEditor:
+    def _editor(self, prefs, style="laser"):
+        return presets.PresetEditor(prefs, style, "Laser")
+
+    def test_lists_only_user_presets(self, qapp, tmp_path):
+        prefs = Preferences(tmp_path)
+        editor = self._editor(prefs)
+        assert editor.list.count() == 0 and not editor.empty.isHidden()
+        presets.save(prefs, "laser", "b")
+        presets.save(prefs, "laser", "A")
+        editor = self._editor(prefs)
+        assert [editor.list.item(i).text() for i in range(2)] == ["A", "b"]
+
+    def test_rename_in_place(self, qapp, tmp_path):
+        prefs = Preferences(tmp_path)
+        presets.save(prefs, "laser", "Old")
+        editor = self._editor(prefs)
+        editor.list.item(0).setText("New")
+        assert list(presets.presets(prefs, "laser")) == ["New"]
+        assert editor.list.item(0).text() == "New"
+
+    def test_rename_to_a_taken_name_is_refused(self, qapp, tmp_path):
+        prefs = Preferences(tmp_path)
+        presets.save(prefs, "laser", "One")
+        presets.save(prefs, "laser", "Two")
+        editor = self._editor(prefs)
+        warned = []
+        editor._warn = warned.append
+        editor.list.item(0).setText("Two")
+        assert warned
+        assert sorted(presets.presets(prefs, "laser")) == ["One", "Two"]
+        assert editor.list.item(0).text() == "One"
+
+    def test_rename_to_default_is_refused(self, qapp, tmp_path):
+        prefs = Preferences(tmp_path)
+        presets.save(prefs, "laser", "One")
+        editor = self._editor(prefs)
+        editor._warn = lambda text: None
+        editor.list.item(0).setText("Default")
+        assert list(presets.presets(prefs, "laser")) == ["One"]
+
+    def test_delete_asks_then_deletes(self, qapp, tmp_path):
+        prefs = Preferences(tmp_path)
+        presets.save(prefs, "laser", "Gone")
+        editor = self._editor(prefs)
+        editor._confirm = lambda text: False
+        editor._delete_current()
+        assert "Gone" in presets.presets(prefs, "laser")
+        editor._confirm = lambda text: True
+        editor._delete_current()
+        assert presets.presets(prefs, "laser") == {}
+        assert not editor.delete_button.isEnabled()
+
+    def test_editing_one_style_leaves_the_others(self, qapp, tmp_path):
+        prefs = Preferences(tmp_path)
+        presets.save(prefs, "bars", "Keep")
+        presets.save(prefs, "laser", "Drop")
+        presets.delete(prefs, "laser", "Drop")
+        assert "Keep" in presets.presets(prefs, "bars")