"""
sn_basis/functions/qgisui_wrapper.py – zentrale QGIS-UI-Abstraktion
"""

from __future__ import annotations

from typing import Any, List, Type


from sn_basis.functions.qt_wrapper import QDockWidget
from sn_basis.functions.qgiscore_wrapper import QgsProject, QGIS_AVAILABLE


iface: Any
QGIS_UI_AVAILABLE = False

QgsFileWidget: Type[Any]
QgsMapLayerComboBox: Type[Any]


# ---------------------------------------------------------
# iface + QGIS-Widgets initialisieren (QGIS oder Mock)
# ---------------------------------------------------------

try:
    from qgis.utils import iface as _iface
    from qgis.gui import (
        QgsFileWidget as _QgsFileWidget,
        QgsMapLayerComboBox as _QgsMapLayerComboBox,
    )

    iface = _iface
    QgsFileWidget = _QgsFileWidget
    QgsMapLayerComboBox = _QgsMapLayerComboBox
    QGIS_UI_AVAILABLE = True

except Exception:
    QGIS_UI_AVAILABLE = False

    class _MockSignal:
        def __init__(self):
            self._callbacks: list[Any] = []

        def connect(self, callback):
            self._callbacks.append(callback)

        def emit(self, *args, **kwargs):
            for cb in list(self._callbacks):
                cb(*args, **kwargs)

    class _MockMessageBar:
        def pushMessage(self, title, text, level=0, duration=5):
            return {
                "title": title,
                "text": text,
                "level": level,
                "duration": duration,
            }

    class _MockIface:
        def messageBar(self):
            return _MockMessageBar()

        def mainWindow(self):
            return None

        def addDockWidget(self, *args, **kwargs):
            pass

        def removeDockWidget(self, *args, **kwargs):
            pass

        def addToolBar(self, *args, **kwargs):
            pass

        def removeToolBar(self, *args, **kwargs):
            pass

    iface = _MockIface()

    class _MockQgsFileWidget:
        GetFile = 0

        def __init__(self, *args, **kwargs):
            self._path = ""
            self.fileChanged = _MockSignal()

        def setStorageMode(self, *args, **kwargs):
            pass

        def setFilter(self, *args, **kwargs):
            pass

        def setFilePath(self, path: str):
            self._path = path
            self.fileChanged.emit(path)

        def filePath(self) -> str:
            return self._path

    class _MockQgsMapLayerComboBox:
        def __init__(self, *args, **kwargs):
            self.layerChanged = _MockSignal()
            self._layer = None
            self._count = 0

        def setFilters(self, *args, **kwargs):
            pass

        def setLayer(self, layer):
            self._layer = layer
            self.layerChanged.emit(layer)

        def count(self) -> int:
            return self._count

        def setCurrentIndex(self, idx: int):
            pass

    QgsFileWidget = _MockQgsFileWidget
    QgsMapLayerComboBox = _MockQgsMapLayerComboBox


# ---------------------------------------------------------
# Main Window
# ---------------------------------------------------------

def get_main_window():
    try:
        return iface.mainWindow()
    except Exception:
        return None


# ---------------------------------------------------------
# Dock-Handling
# ---------------------------------------------------------

def add_dock_widget(area, dock: Any) -> None:
    try:
        iface.addDockWidget(area, dock)
    except Exception:
        pass


def remove_dock_widget(dock: Any) -> None:
    try:
        iface.removeDockWidget(dock)
    except Exception:
        pass


def find_dock_widgets() -> List[Any]:
    main_window = get_main_window()
    if not main_window:
        return []

    try:
        return main_window.findChildren(QDockWidget)
    except Exception:
        return []


# ---------------------------------------------------------
# Menü-Handling
# ---------------------------------------------------------

def add_menu(menu):
    main_window = iface.mainWindow()
    if not main_window:
        return

    # Nur echte Qt-Menüs an Qt übergeben
    if hasattr(menu, "menuAction"):
        main_window.menuBar().addMenu(menu)


def remove_menu(menu):
    main_window = iface.mainWindow()
    if not main_window:
        return

    if hasattr(menu, "menuAction"):
        main_window.menuBar().removeAction(menu.menuAction())


# ---------------------------------------------------------
# Toolbar-Handling
# ---------------------------------------------------------

def add_toolbar(toolbar: Any) -> None:
    try:
        iface.addToolBar(toolbar)
    except Exception:
        pass


def remove_toolbar(toolbar: Any) -> None:
    try:
        iface.removeToolBar(toolbar)
    except Exception:
        pass
# ---------------------------------------------------------
# Layer zum Projekt hinzufügen
# ---------------------------------------------------------

def add_layer_to_project(layer: Any) -> bool:
    """
    Fügt einen Layer dem aktuellen QGIS-Projekt hinzu.

    Diese Funktion kapselt den Zugriff auf ``QgsProject.instance().addMapLayer``
    und dient als zentrale Abstraktion für alle Stellen, die Layer dynamisch
    ins Projekt einfügen möchten (z.B. Pufferlayer im Datenabruf).

    Verhalten
    ---------
    - Wenn QGIS verfügbar ist und der Layer gültig ist, wird er dem Projekt
      hinzugefügt und ``True`` zurückgegeben.
    - Wenn QGIS nicht verfügbar ist oder der Layer ungültig ist, wird
      ``False`` zurückgegeben.
    - Im Mock-Modus wird kein Layer hinzugefügt, aber ``True`` zurückgegeben,
      damit Tests ohne QGIS nicht fehlschlagen.

    Parameters
    ----------
    layer:
        Ein QGIS-Layer (typischerweise ``QgsVectorLayer``), der dem Projekt
        hinzugefügt werden soll.

    Returns
    -------
    bool
        ``True`` bei Erfolg oder im Mock-Modus, sonst ``False``.
    """
    if layer is None:
        return False

    # Mock-Modus: Erfolg simulieren
    if not QGIS_AVAILABLE:
        return True

    try:
        project = QgsProject.instance()
        project.addMapLayer(layer)
        return True
    except Exception:
        return False