from typing import Callable, TYPE_CHECKING, Optional, Union

from kivy.app import App
from kivy.factory import Factory
from kivy.properties import ObjectProperty
from kivy.lang import Builder
from decimal import Decimal
from kivy.clock import Clock

from electrum.util import InvalidPassword
from electrum.gui.kivy.i18n import _

if TYPE_CHECKING:
    from ...main_window import ElectrumWindow
    from electrum.wallet import Abstract_Wallet
    from electrum.storage import WalletStorage

Builder.load_string('''

<PasswordDialog@Popup>
    id: popup
    title: 'Electrum'
    message: ''
    BoxLayout:
        size_hint: 1, 1
        orientation: 'vertical'
        Widget:
            size_hint: 1, 0.05
        Label:
            font_size: '20dp'
            text: root.message
            text_size: self.width, None
            size: self.texture_size
        Widget:
            size_hint: 1, 0.05
        Label:
            id: a
            font_size: '50dp'
            text: '*'*len(kb.password) + '-'*(6-len(kb.password))
            size: self.texture_size
        Widget:
            size_hint: 1, 0.05
        GridLayout:
            id: kb
            size_hint: 1, None
            height: self.minimum_height
            update_amount: popup.update_password
            password: ''
            on_password: popup.on_password(self.password)
            spacing: '2dp'
            cols: 3
            KButton:
                text: '1'
            KButton:
                text: '2'
            KButton:
                text: '3'
            KButton:
                text: '4'
            KButton:
                text: '5'
            KButton:
                text: '6'
            KButton:
                text: '7'
            KButton:
                text: '8'
            KButton:
                text: '9'
            KButton:
                text: 'Clear'
            KButton:
                text: '0'
            KButton:
                text: '<'
''')


class PasswordDialog(Factory.Popup):

    def init(self, app: 'ElectrumWindow', *,
             wallet: Union['Abstract_Wallet', 'WalletStorage'] = None,
             msg: str, on_success: Callable = None, on_failure: Callable = None,
             is_change: int = 0):
        self.app = app
        self.wallet = wallet
        self.message = msg
        self.on_success = on_success
        self.on_failure = on_failure
        self.ids.kb.password = ''
        self.success = False
        self.is_change = is_change
        self.pw = None
        self.new_password = None
        self.title = 'Electrum' + ('  -  ' + self.wallet.basename() if self.wallet else '')

    def check_password(self, password):
        if self.is_change > 1:
            return True
        try:
            self.wallet.check_password(password)
            return True
        except InvalidPassword as e:
            return False

    def on_dismiss(self):
        if not self.success:
            if self.on_failure:
                self.on_failure()
            else:
                # keep dialog open
                return True
        else:
            if self.on_success:
                args = (self.pw, self.new_password) if self.is_change else (self.pw,)
                Clock.schedule_once(lambda dt: self.on_success(*args), 0.1)

    def update_password(self, c):
        kb = self.ids.kb
        text = kb.password
        if c == '<':
            text = text[:-1]
        elif c == 'Clear':
            text = ''
        else:
            text += c
        kb.password = text

    def on_password(self, pw):
        if len(pw) == 6:
            if self.check_password(pw):
                if self.is_change == 0:
                    self.success = True
                    self.pw = pw
                    self.message = _('Please wait...')
                    self.dismiss()
                elif self.is_change == 1:
                    self.pw = pw
                    self.message = _('Enter new PIN')
                    self.ids.kb.password = ''
                    self.is_change = 2
                elif self.is_change == 2:
                    self.new_password = pw
                    self.message = _('Confirm new PIN')
                    self.ids.kb.password = ''
                    self.is_change = 3
                elif self.is_change == 3:
                    self.success = pw == self.new_password
                    self.dismiss()
            else:
                self.app.show_error(_('Wrong PIN'))
                self.ids.kb.password = ''