# ----------------------------------------------------------------------------
# Copyright (c) 2019-2020, Diego Garcia Huerta.
#
# Your use of this software as distributed in this GitHub repository, is
# governed by the BSD 3-clause License.
#
# Your use of the Shotgun Pipeline Toolkit is governed by the applicable license
# agreement between you and Autodesk / Shotgun.
#
# The full license is in the file LICENSE, distributed with this software.
# ----------------------------------------------------------------------------

import os

from krita import Krita
from tank import Hook

__author__ = "Diego Garcia Huerta"
__contact__ = "https://www.linkedin.com/in/diegogh/"


class BreakdownSceneOperations(Hook):
    """
    Breakdown operations for Krita.

    This implementation handles detection of krita read and write nodes.
    """

    def scan_scene(self):
        """
        The scan scene method is executed once at startup and its purpose is
        to analyze the current scene and return a list of references that are
        to be potentially operated on.

        The return data structure is a list of dictionaries. Each scene
        reference that is returned should be represented by a dictionary with
        three keys:

        - "attr": The filename attribute of the 'node' that is to be operated
           on. Most DCCs have a concept of a node, attribute, path or some
           other way to address a particular object in the scene.
        - "type": The object type that this is. This is later passed to the
           update method so that it knows how to handle the object.
        - "path": Path on disk to the referenced object.

        Toolkit will scan the list of items, see if any of the objects matches
        any templates and try to determine if there is a more recent version
        available. Any such versions are then displayed in the UI as out of
        date.
        """

        # not much to do here for this engine, really.
        # but it is handy to know what is loaded.

        # this is a bit dogy, but works, we hide the update
        # button as it is not needed.
        app = self.parent
        engine = app.engine

        for widget in engine.created_qt_dialogs:
            if widget._widget._app == app:
                widget._widget.ui.update.hide()
                break

        # Introspect the krita scene for read and write nodes
        # so we can gather the filenames available.
        refs = []

        krita_app = Krita.instance()
        documents = krita_app.documents()

        for doc in documents:
            ref_path = doc.fileName()
            if ref_path:
                refs.append({"node": doc, "type": "file", "path": ref_path})

        return refs

    def update(self, items):
        """
        Perform replacements given a number of scene items passed from the app.

        Once a selection has been performed in the main UI and the user clicks
        the update button, this method is called.

        The items parameter is a list of dictionaries on the same form as was
        generated by the scan_scene hook above. The path key now holds
        the that each attribute should be updated *to* rather than the current
        path.
        """

        pass