# SPDX-License-Identifier: LGPL-2.1-or-later
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""" Contains a parameter observer class and several related functions."""

import FreeCAD as App
import FreeCADGui as Gui
from PySide import QtGui

from draftutils import init_draft_statusbar
from draftutils import utils
from draftutils.translate import translate
from draftviewproviders import view_base

class ParamObserver:

    def slotParamChanged(self, param, tp, name, value):
        if name in ("gridBorder", "gridShowHuman", "coloredGridAxes", "gridEvery",
                    "gridSpacing", "gridSize", "gridTransparency", "gridColor"):
            _param_observer_callback_grid()
            return
        if name == "DisplayStatusbarSnapWidget":
            _param_observer_callback_snapwidget()
            return
        if name == "DisplayStatusbarScaleWidget":
            _param_observer_callback_scalewidget()
            return
        if name == "snapStyle":
            _param_observer_callback_snapstyle()
            return
        if name == "snapcolor":
            _param_observer_callback_snapcolor()
            return
        if name == "patternFile":
            _param_observer_callback_svg_pattern()
            return


def _param_observer_callback_grid():
    if hasattr(App, "draft_working_planes") and hasattr(Gui, "Snapper"):
        try:
            trackers = Gui.Snapper.trackers
            for wp in App.draft_working_planes[1]:
                view = wp._view
                if view in trackers[0]:
                    i = trackers[0].index(view)
                    grid = trackers[1][i]
                    grid.pts = []
                    grid.reset()
                    grid.displayHumanFigure(wp)
                    grid.setAxesColor(wp)
        except Exception:
            pass


def _param_observer_callback_snapwidget():
    if Gui.activeWorkbench().name() == "DraftWorkbench":
        init_draft_statusbar.hide_draft_statusbar()
        init_draft_statusbar.show_draft_statusbar()
        return
    msg = translate("draft",
"""The Snap widget is only available in the Draft Workbench.
Switch to that workbench to see the result of this change.""")
    QtGui.QMessageBox.information(None, "Update Draft statusbar widget", msg,
                                  QtGui.QMessageBox.Ok)


def _param_observer_callback_scalewidget():
    if Gui.activeWorkbench().name() == "DraftWorkbench":
        init_draft_statusbar.hide_draft_statusbar()
        init_draft_statusbar.show_draft_statusbar()
        return
    msg = translate("draft",
"""The Annotation scale widget is only available in the Draft Workbench.
Switch to that workbench to see the result of this change.""")
    QtGui.QMessageBox.information(None, "Update Draft statusbar widget", msg,
                                  QtGui.QMessageBox.Ok)


def _param_observer_callback_snapstyle():
    if hasattr(Gui, "Snapper"):
        Gui.Snapper.set_snap_style()


def _param_observer_callback_snapcolor():
    if hasattr(Gui, "Snapper"):
        for snap_track in Gui.Snapper.trackers[2]:
            snap_track.setColor()


def _param_observer_callback_svg_pattern():
    utils.load_svg_patterns()
    if App.ActiveDocument is None:
        return
    msg = translate("draft",
"""Do you want to update the SVG pattern options
of existing objects in all opened documents?""")
    res = QtGui.QMessageBox.question(None, "Update SVG patterns", msg,
                                     QtGui.QMessageBox.Yes | QtGui.QMessageBox.No,
                                     QtGui.QMessageBox.No)
    if res == QtGui.QMessageBox.No:
        return
    pats = list(utils.svg_patterns())
    pats.sort()
    pats = ["None"] + pats
    for doc in App.listDocuments().values():
        doc.openTransaction("SVG pattern update")
        for obj in doc.Objects:
            if hasattr(obj, "ViewObject") \
                    and hasattr(obj.ViewObject, "Pattern") \
                    and hasattr(obj.ViewObject, "Proxy") \
                    and isinstance(obj.ViewObject.Proxy, view_base.ViewProviderDraft):
                vobj = obj.ViewObject
                old = vobj.Pattern
                if old in pats:
                    vobj.Pattern = pats
                else:
                    tmp_pats = [old] + pats[1:]
                    tmp_pats.sort()
                    vobj.Pattern = ["None"] + tmp_pats
                vobj.Pattern = old
        doc.commitTransaction()


def _param_observer_start(param = App.ParamGet("User parameter:BaseApp/Preferences/Mod/Draft")):
    param.AttachManager(ParamObserver())