wip: navigation system - NavItemWidgets

ui/navigation/navitemwidgets.py

@@ -0,0 +1,84 @@
+from PySide6.QtCore import QObject
+from PySide6.QtGui import QFont
+from PySide6.QtWidgets import QLabel, QSizePolicy, QSpacerItem, QVBoxLayout, QWidget
+
+from ui.navigation.navhost import NavHost, navHost
+from ui.navigation.navitem import NavItem
+from ui.navigation.navsidebar import NavigationSideBar
+
+
+class DefaultParentNavItemWidget(QWidget):
+    def __init__(self, navItem: NavItem, navItemChildren: list[NavItem], parent=None):
+        super().__init__(parent)
+
+        self.navItem = navItem
+
+        self.partialNavHost = NavHost(self)
+        self.partialNavHost.registerNavItem(navItem)
+        for _navItem in navItemChildren:
+            self.partialNavHost.registerNavItem(_navItem)
+        self.partialNavHost.navigate(navItem.id)
+
+        self.verticalLayout = QVBoxLayout(self)
+
+        self.navItemLabelFont = QFont(self.font())
+        self.navItemLabelFont.setPointSize(14)
+        self.navItemLabel = QLabel(self)
+        self.navItemLabel.setFont(self.navItemLabelFont)
+
+        spacer = QSpacerItem(
+            20, 20, QSizePolicy.Policy.Preferred, QSizePolicy.Policy.Expanding
+        )
+
+        self.verticalLayout.addSpacerItem(spacer)
+
+        self.navSideBar = NavigationSideBar(self, self.partialNavHost)
+        self.navSideBar.navigateUpButton.setEnabled(False)
+        self.verticalLayout.addWidget(self.navSideBar)
+
+        self.verticalLayout.addSpacerItem(spacer)
+
+        self.retranslateUi()
+
+    def retranslateUi(self):
+        self.navItemLabel.setText(self.navItem.text())
+
+
+class NavItemWidgets(QObject):
+    def __init__(self, parent=None):
+        super().__init__(parent)
+
+        self.__map: dict[str, QWidget] = {}
+        # this reference holds all the `DefaultParentNavItemWidget`s
+        # since these widgets are created with no parents, not keeping a reference to
+        # them may result in errors, even a silent app crash that is hard to debug
+        self.__defaultParentWidgetRefs: dict[str, QWidget] = {}
+
+    def register(self, navItemId: str, widget: QWidget):
+        self.__map[navItemId] = widget
+
+    def unregister(self, navItemId: str) -> bool:
+        try:
+            widget = self.__map.pop(navItemId)
+            widget.deleteLater()
+            return True
+        except KeyError:
+            return False
+
+    def get(self, navItemId: str) -> QWidget | None:
+        widget = self.__map.get(navItemId)
+        if widget is not None:
+            return widget
+        elif navItemChildren := navHost.getNavItemRelatives(navItemId).children:
+            if self.__defaultParentWidgetRefs.get(navItemId) is None:
+                defaultParentNavItemWidget = DefaultParentNavItemWidget(
+                    navHost.findNavItem(navItemId), navItemChildren
+                )
+                self.__defaultParentWidgetRefs[navItemId] = defaultParentNavItemWidget
+                defaultParentNavItemWidget.partialNavHost.activated.connect(
+                    lambda o, n: navHost.navigate(n.id)
+                )
+
+            return self.__defaultParentWidgetRefs.get(navItemId)
+        else:
+            return None