import pyblish
from avalon.nuke import lib as anlib
import nuke


class SelectCenterInNodeGraph(pyblish.api.Action):
    """
    Centering failed instance node in node grap
    """

    label = "Center node in node graph"
    icon = "wrench"
    on = "failed"

    def process(self, context, plugin):

        # Get the errored instances
        failed = []
        for result in context.data["results"]:
            if (result["error"] is not None and result["instance"] is not None
               and result["instance"] not in failed):
                failed.append(result["instance"])

        # Apply pyblish.logic to get the instances for the plug-in
        instances = pyblish.api.instances_by_plugin(failed, plugin)

        all_xC = list()
        all_yC = list()

        # maintain selection
        with anlib.maintained_selection():
            # collect all failed nodes xpos and ypos
            for instance in instances:
                bdn = instance[0]
                xC = bdn.xpos() + bdn.screenWidth()/2
                yC = bdn.ypos() + bdn.screenHeight()/2

                all_xC.append(xC)
                all_yC.append(yC)

        self.log.info("all_xC: `{}`".format(all_xC))
        self.log.info("all_yC: `{}`".format(all_yC))

        # zoom to nodes in node graph
        nuke.zoom(2, [min(all_xC), min(all_yC)])


@pyblish.api.log
class ValidateBackdrop(pyblish.api.InstancePlugin):
    """Validate amount of nodes on backdrop node in case user
    forgoten to add nodes above the publishing backdrop node"""

    order = pyblish.api.ValidatorOrder
    optional = True
    families = ["nukenodes"]
    label = "Validate Backdrop"
    hosts = ["nuke"]
    actions = [SelectCenterInNodeGraph]

    def process(self, instance):
        connections_out = instance.data["connections_out"]

        msg_multiple_outputs = "Only one outcoming connection from \"{}\" is allowed".format(
            instance.data["name"])
        assert len(connections_out.keys()) <= 1, msg_multiple_outputs

        msg_no_content = "No content on backdrop node: \"{}\"".format(
            instance.data["name"])
        assert len(instance) > 1, msg_no_content