Example Plugin: SceneBuilder
***************************************

This example plugin builds a Maya shot scenefile by importing all USD assets which are linked to the current shot.

The import can be triggered from a custom menu in the Project Browser.

See the section for :ref:`Single File Plugins<single_file_plugins>` on how to load this example.

.. code-block:: python

    name = "SceneBuilder"
    classname = "SceneBuilder"


    from qtpy.QtWidgets import *


    class SceneBuilder:
        def __init__(self, core):
            self.core = core
            self.version = "v1.0.0"

            # only in Maya
            if self.core.appPlugin.pluginName == "Maya":
                self.core.registerCallback("onProjectBrowserStartup", self.onProjectBrowserStartup, plugin=self)
                self.core.registerCallback("postInitialize", self.postInitialize, plugin=self)
                
                if self.core.pb:
                    self.onProjectBrowserStartup(self.core.pb)

                if self.core.status != "starting":
                    self.postInitialize()

        def postInitialize(self):
            # set the function, which handles the import for USD files
            importKwargs = {"type": "USD Import", "importFunction": self.maya_importUsd}
            self.core.appPlugin.importHandlers[".usd"] = importKwargs
            self.core.appPlugin.importHandlers[".usda"] = importKwargs
            self.core.appPlugin.importHandlers[".usdc"] = importKwargs

        def onProjectBrowserStartup(self, origin):
            # add a Scene Builder menu to the Project Browser
            origin.myMenu = QMenu("Scene Builder")
            origin.myMenu.addAction("Import connected assets", self.onImportTriggered)
            origin.menubar.addMenu(origin.myMenu)

        def onImportTriggered(self):
            # get the entity from the current scenefile
            fileName = self.core.getCurrentFileName()
            currentEntity = self.core.getScenefileData(fileName)

            if currentEntity.get("type") != "shot":
                self.core.popup("You need to be in a shot scenefile to use the scene builder.")
                return

            sm = self.core.getStateManager()
            with self.core.waitPopup(self.core, "Gathering products...") as popup:
                productsToImport = []

                # find out which assets are connected to our current shot
                entities = self.core.entities.getConnectedEntities(currentEntity)

                # find products with the "usd" tag for each entity
                for centity in entities:
                    products = self.core.products.getProductsByTags(centity, ["usd"])
                    productsToImport += products

                for idx, product in enumerate(productsToImport):
                    if "asset_path" not in product:
                        continue

                    # update popup text
                    text = "Importing %s (%s/%s)" % (product["asset_path"], idx+1, len(productsToImport))
                    popup.msg.setText(text)
                    QApplication.processEvents()

                    # get filepath and import it
                    payloadPath = self.core.products.getLatestVersionpathFromProduct(product["product"], entity=product)
                    primPath = "/assets/" + product["asset_path"]
                    sm.importFile(payloadPath)
                    print("added file to stage: %s - %s" % (primPath, payloadPath))

        def maya_importUsd(self, filepath, kwargs):
            mode = "reference"  # can be "layer"
            return self.core.getPlugin("USD").api.maya_importUsdStage(filepath, kwargs, mode=mode)