from PyQt5 import QtCore
from typing import Optional, List

from todo.model.task import ValidTaskForm
from todo.model.difficulty import Difficulty
from todo.model.priority import Priority
import todo.gui.tasks.duration
import todo.gui.tags.list

class TaskFormEdition:
    def __init__(
            self,
            name,
            name_signal,
            duration,
            duration_signal,
            difficulty,
            difficulty_signal,
            priority,
            priority_signal,
            tags: List[int],
            tags_signal: todo.gui.tags.list.SelectionSignal,
            description,
            description_signal):

        self._name = name
        self._duration = duration
        self._difficulty = difficulty
        self._priority = priority
        self._tags = tags
        self._description = description
        self._signal = ValidTaskFormSignal()

        name_signal.connect(lambda n: self.on_name_signal(n))
        duration_signal.connect(lambda d: self.on_duration_signal(d))
        difficulty_signal.connect(lambda d: self.on_difficulty_signal(d))
        priority_signal.connect(lambda p: self.on_priority_signal(p))
        tags_signal.connect(lambda ts: self.on_tags_signal(ts))
        description_signal.connect(lambda d: self.on_description_signal(d))

    def get(self) -> Optional[ValidTaskForm]:
        name = self._name.strip()
        duration = todo.gui.tasks.duration.parse(self._duration)
        difficulty = self._difficulty
        priority = self._priority
        description = self._description.strip()

        if name and duration != None:
            return ValidTaskForm(
                name = name,
                duration = duration,
                difficulty = difficulty,
                priority = priority,
                tags = self._tags,
                description = description)
        else:
            return None

    def on_name_signal(self, name: str):
        self._name = name
        self.emit()

    def on_duration_signal(self, duration: str):
        self._duration = duration
        self.emit()

    def on_difficulty_signal(self, index: int):
        self._difficulty = Difficulty(index)
        self.emit()

    def on_priority_signal(self, index: int):
        self._priority = Priority(index)
        self.emit()

    def on_tags_signal(self, tags: List[int]):
        self._tags = tags
        self.emit()

    def on_description_signal(self, description: str):
        self._description = description
        self.emit()

    def emit(self):
        validForm = self.get()
        if validForm:
            self._signal.emit(validForm)

    def signal(self):
        return self._signal

class ValidTaskFormSignal(QtCore.QObject):
    _signal = QtCore.pyqtSignal(ValidTaskForm, name = "validTaskForm")

    def __init__(self):
        QtCore.QObject.__init__(self)

    def emit(self, form: Optional[ValidTaskForm]):
        self._signal.emit(form)

    def connect(self, f):
        self._signal.connect(f)