# -*- coding: utf-8 -*-
from PyQt4.QtCore import pyqtSignal
from PyQt4.QtGui import *
import sys

# Модель      
class Api(object):
    def login(self, username, password):
        return username == 'admin' and password == '1'

# Вид
class LoginForm(QDialog):
    # Почему работает только если объявить тут?
    submitted = pyqtSignal(unicode, unicode)
    success = pyqtSignal()
    fail = pyqtSignal(unicode)
     
    def __init__(self, parent=None):
        super(LoginForm, self).__init__(parent)
        self.setupUi()
        self.loginBtn.clicked.connect(self.onLogin)
        self.success.connect(self.onSuccess)
        self.fail.connect(self.onFail)
        
    def setupUi(self):
        self.setFixedSize(300, 150)
        self.setWindowTitle(u"Авторизация")
        self.vlayout = QVBoxLayout(self)
        self.errorLbl = QLabel(self)
        self.errorLbl.setWordWrap(True)
        self.errorLbl.setStyleSheet("color: red")
        # Не отображаем элемент.
        self.errorLbl.hide()
        self.vlayout.addWidget(self.errorLbl)    
        self.formLayout = QFormLayout(self)  
        self.usernameLbl = QLabel(self)
        self.usernameLbl.setText(u"Имя пользователя:")
        self.usernameLe = QLineEdit(self)
        self.formLayout.addRow(self.usernameLbl, self.usernameLe)
        self.passwordLbl = QLabel(self)
        self.passwordLbl.setText(u"Пароль:")
        self.passwordLe = QLineEdit(self)
        self.passwordLe.setEchoMode(QLineEdit.Password)
        self.formLayout.addRow(self.passwordLbl, self.passwordLe)
        self.vlayout.addLayout(self.formLayout)
        # Прижимаем форму кверху.
        spacer = QSpacerItem(0, 0, QSizePolicy.Minimum, QSizePolicy.Expanding)
        self.vlayout.addItem(spacer)
        # Прижимаем кнопку к правому краю.
        self.hlayout = QHBoxLayout(self)
        spacer1 = QSpacerItem(0, 0, QSizePolicy.Expanding, QSizePolicy.Minimum)
        self.hlayout.addItem(spacer1)
        self.loginBtn = QPushButton(self)
        self.loginBtn.setText(u"Логин")
        self.hlayout.addWidget(self.loginBtn)
        self.vlayout.addLayout(self.hlayout)
        
    def onLogin(self):
        username = unicode(self.usernameLe.text()).strip()
        password = unicode(self.passwordLe.text()).strip()
        
        if not username:
            self.showError(u"Введите имя пользователя.")   
        elif not password:
            self.showError(u"Введите пароль.")
        else:
            self.errorLbl.hide() 
            self.submitted.emit(username, password)
            
    def showError(self, text):
        self.errorLbl.show()
        self.errorLbl.setText(text)
            
    def onSuccess(self):
        self.close()
        
    def onFail(self, reason):
        self.showError(reason)
    
# Presenter
class App(object):
    def __init__(self):
        self.api = Api()
        self.app = QApplication.instance() or QApplication(sys.argv)
        self.loginForm = LoginForm()
        self.loginForm.submitted.connect(self.login)
        
    def login(self, username, password):
        if self.api.login(username, password):
            # Авторизовались и закрываем форму.
            return self.loginForm.success.emit()
        
        self.loginForm.fail.emit(u"Неправильное имя пользователя или пароль.")
        
    def run(self):
        self.loginForm.show()
        self.app.exec_()

def main():
    app = App()
    app.run()

if '__main__' == __name__:
    main()

# -*- coding: utf-8 -*-
from ui.login import Ui_LoginDialog
from PyQt4.QtGui import QApplication, QDialog

class Model:    
    users = [{"id": 1, "username": "Admin", "password": "1", "role": "admin"},
             {"id": 2, "username": "tester", "password": "test", "role": "user"}]
    
    def __init__(self, controller):
        self.controller = controller
    
    def login(self, username, password):
        for user in self.users:
            if user['username'] == username and user['password'] == password:
                return {"id": user['id'], "username": user['username'], "role": user['role']}
            
        return {"error": "Invalid username or password."}

class View(QDialog, Ui_LoginDialog):
    def __init__(self, controller):
        QDialog.__init__(self)
        self.setupUi(self)
        self.controller = controller
        self.errorLabel.setStyleSheet("color: red")
        self.errorLabel.hide()
        self.loginButton.clicked.connect(self.onLogin)
        
    def onLogin(self):
        self.errorLabel.hide()
        username = unicode(self.usernameEdit.text())
        password = unicode(self.passwordEdit.text())
        self.controller.login(username, password)
    
    def setErrorLabel(self, text):
        self.errorLabel.show()
        self.errorLabel.setText(text)
        
class Controller:
    def __init__(self):
        self.model = Model(self)
        self.view = View(self)
        self.view.show()
        
    def login(self, username, password):
        username = username.strip()
        password = password.strip()
        
        if not username:
            self.view.setErrorLabel(u"Введите имя пользователя.")
        elif not password:  
            self.view.setErrorLabel(u"Введите пароль.")
        else:
            result = self.model.login(username, password)
            
            if 'error' in result:
                self.view.setErrorLabel(result['error'])
            else:
                print u"Вы авторизовались как {username}.".format(**result)
                self.view.close()
        
if __name__ == '__main__':
    a = QApplication([])
    c = Controller()
    a.exec_()

# -*- coding: utf-8 -*-
from PyQt4.QtGui import QApplication, QMainWindow
from PyQt4.QtCore import pyqtSignal
from ui.form import Ui_Form

class Model:
    km = 0
    miles = 0
    ratio = 1.609344
    
    def setKilometres(self, value):
        self.km = value
        self.miles = value / self.ratio
        
    def setMiles(self, value):
        self.miles = value
        self.km = value * self.ratio
        
class View(QMainWindow, Ui_Form):
    onKilometresChange = pyqtSignal([int, float])
    onMilesChange = pyqtSignal([int, float])
    
    def __init__(self):
        QMainWindow.__init__(self)
        self.setupUi(self)
        self.lineEdit_km.textEdited.connect(self._onKilometresChange)
        self.lineEdit_miles.textEdited.connect(self._onMilesChange)
        
    def setKilometres(self, value):
        self.lineEdit_km.setText( str( self.parseNumber(value) ) )
        
    def setMiles(self, value):
        self.lineEdit_miles.setText( str( self.parseNumber(value) ) )
        
    def _onKilometresChange(self):
        self.onKilometresChange( self.parseNumber( self.lineEdit_km.text() ) )
        
    def _onMilesChange(self):
        self.onMilesChange( self.parseNumber( self.lineEdit_miles.text() ) )
        
    def parseNumber(self, v):
        try:
            v = float(v)
        except:
            return 0
        
        if v % 1 == 0:
            return int(v)
        
        return round(v, 2)
        
class Presenter:
    def __init__(self, model, view):
        self.model = model
        self.view = view
        self.view.onKilometresChange = self.convertMiles
        self.view.onMilesChange = self.convertKilometres
        
    def convertMiles(self, km):
        self.model.setKilometres(km)
        self.view.setMiles(self.model.miles)
        
    def convertKilometres(self, miles):
        self.model.setMiles(miles)
        self.view.setKilometres(self.model.km)
        
if  __name__ == '__main__':
    a = QApplication([])
    m = Model()
    v = View()
    p = Presenter(m, v)
    v.show()
    a.exec_()

# -*- coding: utf-8 -*-

# Form implementation generated from reading ui file '.\form.ui'
#
# Created: Tue Dec 30 08:47:22 2014
#      by: PyQt4 UI code generator 4.11.3
#
# WARNING! All changes made in this file will be lost!

from PyQt4 import QtCore, QtGui

try:
    _fromUtf8 = QtCore.QString.fromUtf8
except AttributeError:
    def _fromUtf8(s):
        return s

try:
    _encoding = QtGui.QApplication.UnicodeUTF8
    def _translate(context, text, disambig):
        return QtGui.QApplication.translate(context, text, disambig, _encoding)
except AttributeError:
    def _translate(context, text, disambig):
        return QtGui.QApplication.translate(context, text, disambig)

class Ui_Form(object):
    def setupUi(self, Form):
        Form.setObjectName(_fromUtf8("Form"))
        Form.resize(320, 240)
        self.widget = QtGui.QWidget(Form)
        self.widget.setGeometry(QtCore.QRect(10, 10, 205, 48))
        self.widget.setObjectName(_fromUtf8("widget"))
        self.formLayout = QtGui.QFormLayout(self.widget)
        self.formLayout.setMargin(0)
        self.formLayout.setObjectName(_fromUtf8("formLayout"))
        self.label = QtGui.QLabel(self.widget)
        self.label.setObjectName(_fromUtf8("label"))
        self.formLayout.setWidget(0, QtGui.QFormLayout.LabelRole, self.label)
        self.lineEdit_km = QtGui.QLineEdit(self.widget)
        self.lineEdit_km.setObjectName(_fromUtf8("lineEdit_km"))
        self.formLayout.setWidget(0, QtGui.QFormLayout.FieldRole, self.lineEdit_km)
        self.label_2 = QtGui.QLabel(self.widget)
        self.label_2.setObjectName(_fromUtf8("label_2"))
        self.formLayout.setWidget(1, QtGui.QFormLayout.LabelRole, self.label_2)
        self.lineEdit_miles = QtGui.QLineEdit(self.widget)
        self.lineEdit_miles.setObjectName(_fromUtf8("lineEdit_miles"))
        self.formLayout.setWidget(1, QtGui.QFormLayout.FieldRole, self.lineEdit_miles)

        self.retranslateUi(Form)
        QtCore.QMetaObject.connectSlotsByName(Form)

    def retranslateUi(self, Form):
        Form.setWindowTitle(_translate("Form", "Перевод из километров в мили", None))
        self.label.setText(_translate("Form", "Километры: ", None))
        self.lineEdit_km.setText(_translate("Form", "0", None))
        self.label_2.setText(_translate("Form", "Мили:", None))
        self.lineEdit_miles.setText(_translate("Form", "0", None))