import sys
import unittest
import numpy as np
import webbrowser

from unittest.mock import MagicMock

from PyQt5 import QtGui, QtWidgets

# set up import paths
import path_prepare

# Local
from sas.qtgui.Perspectives.Fitting.MultiConstraint import MultiConstraint

if not QtWidgets.QApplication.instance():
    app = QtWidgets.QApplication(sys.argv)

class MultiConstraintTest(unittest.TestCase):
    '''Test the MultiConstraint dialog'''
    def setUp(self):
        '''Create MultiConstraint dialog'''
        params = ['p1', 'p2']
        self.p1 = params[0]
        self.p2 = params[1]
        self.widget = MultiConstraint(parent=None, params=params)

    def tearDown(self):
        '''Destroy the GUI'''
        self.widget.close()
        self.widget = None

    def testDefaults(self):
        '''Test the GUI in its default state'''
        self.assertIsInstance(self.widget, QtWidgets.QDialog)
        # Default title
        self.assertEqual(self.widget.windowTitle(), "2 parameter constraint")

        # modal window
        self.assertTrue(self.widget.isModal())

    def testLabels(self):
        ''' various labels on the widget '''
        # params related setup
        self.assertEqual(self.widget.txtParam1.text(), self.p1)
        self.assertEqual(self.widget.txtParam1_2.text(), self.p1)
        self.assertEqual(self.widget.txtParam2.text(), self.p2)

    def testTooltip(self):
        ''' test the tooltip'''
        tooltip = "E.g.\n%s = 2.0 * (%s)\n" %(self.p1, self.p2)
        tooltip += "%s = sqrt(%s) + 5"%(self.p1, self.p2)
        self.assertEqual(self.widget.txtConstraint.toolTip(), tooltip)

    def testValidateFormula(self):
        ''' assure enablement and color for valid formula '''
        # Invalid string
        self.widget.validateConstraint = MagicMock(return_value=False)
        self.widget.validateFormula()
        style_sheet = "QLineEdit {background-color: red;}"
        self.assertFalse(self.widget.cmdOK.isEnabled())
        self.assertEqual(self.widget.txtConstraint.styleSheet(),style_sheet)

        # Valid string
        self.widget.validateConstraint = MagicMock(return_value=True)
        self.widget.validateFormula()
        style_sheet = "QLineEdit {background-color: white;}"
        self.assertTrue(self.widget.cmdOK.isEnabled())
        self.assertEqual(self.widget.txtConstraint.styleSheet(),style_sheet)

    def testValidateConstraint(self):
        ''' constraint validator test'''
        #### BAD
        # none
        self.assertFalse(self.widget.validateConstraint(None))
        # inf
        self.assertFalse(self.widget.validateConstraint(np.inf))
        # 0
        self.assertFalse(self.widget.validateConstraint(0))
        # ""
        self.assertFalse(self.widget.validateConstraint(""))
        # p2_
        self.assertFalse(self.widget.validateConstraint("p2_"))
        # p1
        self.assertFalse(self.widget.validateConstraint("p1"))

        ### GOOD
        # p2
        self.assertTrue(self.widget.validateConstraint("p2"))
        # " p2    "
        self.assertTrue(self.widget.validateConstraint(" p2    "))
        # sqrt(p2)
        self.assertTrue(self.widget.validateConstraint("sqrt(p2)"))
        # -p2
        self.assertTrue(self.widget.validateConstraint("-p2"))
        # log10(p2) - sqrt(p2) + p2
        self.assertTrue(self.widget.validateConstraint("log10(p2) - sqrt(p2) + p2"))
        # log10(    p2    ) +  p2
        self.assertTrue(self.widget.validateConstraint("log10(    p2    ) +  p2  "))

    def testOnHelp(self):
        """
        Test the default help renderer
        """
        webbrowser.open = MagicMock()

        # invoke the tested method
        self.widget.onHelp()

        # see that webbrowser open was attempted
        webbrowser.open.assert_called_once()