from UM.Application import Application
from UM.Qt.ListModel import ListModel

from PyQt5.QtCore import pyqtProperty, Qt, pyqtSignal, pyqtSlot, QUrl

from UM.Settings.ContainerRegistry import ContainerRegistry
from UM.Settings.InstanceContainer import InstanceContainer

class ContainerSettingsModel(ListModel):
    LabelRole = Qt.UserRole + 1
    CategoryRole = Qt.UserRole + 2
    UnitRole = Qt.UserRole + 3
    ValuesRole = Qt.UserRole + 4

    def __init__(self, parent = None):
        super().__init__(parent)
        self.addRoleName(self.LabelRole, "label")
        self.addRoleName(self.CategoryRole, "category")
        self.addRoleName(self.UnitRole, "unit")
        self.addRoleName(self.ValuesRole, "values")

        self._container_ids = []
        self._container = None

    def _onPropertyChanged(self, key, property_name):
        if property_name == "value":
            self._update()

    def _update(self):
        self.clear()

        if len(self._container_ids) == 0:
            return

        keys = []
        for container in self._containers:
            keys = keys + list(container.getAllKeys())

        keys = list(set(keys)) # remove duplicate keys
        keys.sort()

        for key in keys:
            definition = None
            category = None
            values = []
            for container in self._containers:
                instance = container.getInstance(key)
                if instance:
                    definition = instance.definition

                    # Traverse up to find the category
                    category = definition
                    while category.type != "category":
                        category = category.parent

                    values.append(container.getProperty(key, "value"))
                else:
                    values.append("")

            self.appendItem({
                "key": key,
                "values": values,
                "label": definition.label,
                "unit": definition.unit,
                "category": category.label
            })

    ##  Set the ids of the containers which have the settings this model should list.
    #   Also makes sure the model updates when the containers have property changes
    def setContainers(self, container_ids):
        for container in self._containers:
            container.propertyChanged.disconnect(self._onPropertyChanged)

        self._container_ids = container_ids
        self._containers = []

        for container_id in self._container_ids:
            containers = ContainerRegistry.getInstance().findContainers(id = container_id)
            if containers:
                containers[0].propertyChanged.connect(self._onPropertyChanged)
                self._containers.append(containers[0])

        self._update()

    containersChanged = pyqtSignal()
    @pyqtProperty("QVariantList", fset = setContainers, notify = containersChanged)
    def containers(self):
        return self.container_ids